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Input Text: Read the passage below and choose the right answer to the following question (choices are Eric or Rita ):

The more carbon atoms a hydrocarbon has, the greater the number of isomers.


Eric has a hydrocarbon with 20 carbon atoms. Rita has a hydrocarbon with 35 carbon atoms. Whose hydrocarbon has more isomers Eric or Rita?

Target Text: Rita

#### Retrieved Documents ####

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Retrieved Text: A major class of organic compounds where carbon and hydrogen molecules are arranged in straight or branched chains. A type of hydrocarbon . Includes alkane s, alkene s, and alkyne s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where all of the carbon-carbon bonds are single bonds. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a double bond. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a triple bond. One of three major classes of aliphatic hydrocarbon s.
Molecules which are almost entirely carbon and hydrogen, but have had at least one chlorine atom introduced to them that has replaced one of their hydrogen atoms.
A hydrocarbon (molecule of carbon and hydrogen only) with 27 carbon atoms that is the parent structure of all mammalian steroid s.
Any of several enzyme s that put double bonds into the hydrocarbon areas of fatty acid s.
Any in a family of over 200 chlorinated organic chemicals (all heterocyclic hydrocarbons). The term is most commonly applied to a particular chemical, 2,3,7,8-tetrachlorodibenzo-paradioxin (2,3,7,8-TCDD, simply called TCDD), which is an impurity in the defoliant Agent Orange and in the pesticide 2,4,5-T (see auxin ). Dioxins are also produced when chlorinated materials such as plastics are burned. Dioxins are known to cause skin diseases (chloracne), birth defects, miscarriages, and cancer .
A

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Retrieved Text: Chapter L3 Section 4 Organic Compounds The Four Bonds of a Carbon Atom More than 90% of all compounds belong to a group called organic compounds. Organic compounds are covalent compounds composed of carbon-based molecules. Fuel, rubbing alcohol, sugar, cotton, paper and plastic belong to this group. All organic compounds contain carbon. Each carbon atom has four valence electrons so each carbon atom can make four bonds with four other atoms.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Carbon Backbones Structural formulas are models that are used to show how atoms in a molecule are connected. Each line represents a pair of electrons that form a covalent bond.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Many organic compounds are based on the types of carbon backbones shown below. Some compounds have hundreds or thousands of carbon atoms as part of their backbone.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Organic compounds may also contain hydrogen, oxygen, sulfur, nitrogen, and phosphorus. The next slide shows three models of carbon backbones.
Section 4 Organic Compounds Hydrocarbons and Other Organic Compounds Many organic compounds contain several kinds of atoms, but some contain only two. Organic compounds that contain only carbon and hydrogen are called hydrocarbons. There are three types of hydrocarbons: saturated hydrocarbons, unsaturated hydrocarbons, and aromatic hydrocarbons.
Chapter L3 Section 4 Organic Compounds Hydrocarbons, continued Saturated Hydrocarbons An alkane, or saturated hydrocarbon, is a hydrocarbon in which each carbon atom in the molecule shares a single bond with

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Retrieved Text: Any organic compound composed only of carbon and hydrogen.
Any organic compound composed only of carbon and hydrogen. Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.
Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: Hydrocarbon, an organic chemical compound composed of carbon and hydrogen. Hydrocarbons may be gases, liquids, or solids. In nature, they are found mainly in plants, petroleum, natural gas, coal, and oil shale. Most burn readily and dissolve more readily in alcohol than in water. Some are toxic and some form an explosive mixture with air. Hydrocarbons are used as fuels and solvents and in the manufacture of industrial chemicals, explosives, plastics, synthetic rubber, dyes, drugs, and other products.
More than 100,000 hydrocarbons are known. The main reason there are so many of these compounds is that carbon atoms can unite in many different ways to form complex chain or ring frameworks. Different arrangements of atoms yield different molecules. For example, the formula C30 H62 (30 carbon atoms and 62 hydrogen atoms) represents 4,111,846,763 possible isomers—compounds whose molecules differ only in structure.
In chemistry, compounds closely related in structure to hydrocarbons are called hydrocarbon derivatives. Such compounds consist of carbon, hydrogen, and other elements, usually oxygen, nitrogen, chlorine, phosphorus, or sulfur. They are often named for the hydrocarbons to which they are most closely related. For example, the organic chloride compound most closely related to ethane is called ethyl chloride. Hydrocarbons and their derivatives form a large part of the subject matter of organic chemistry.
Hydrocarbons are divided into two main groups according to structure—aliphatic (or acyclic) hydrocarbons and cyclic hydrocarbons. They are further divided into groups of compounds having similar chemical properties. Members within a group are called homologs, and each complete group is called a homologous series. Neighboring

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: This page deals briefly with the combustion of alkanes and cycloalkanes. In fact, there is very little difference between the two.
Complete combustion (given sufficient oxygen) of any hydrocarbon produces carbon dioxide and water. It is quite important that you can write properly balanced equations for these reactions, because they often come up as a part of thermochemistry calculations. Some are easier than others. For example, with alkanes, the ones with an even number of carbon atoms are marginally harder than those with an odd number!
With butane (C4H10), you can again balance the carbons and hydrogens as you write the equation down.
Counting the oxygens leads to a slight problem - with 13 on the right-hand side. The simple trick is to allow yourself to have "six-and-a-half" O2 molecules on the left.
The hydrocarbons become harder to ignite as the molecules get bigger. This is because the bigger molecules don't vaporize so easily - the reaction is much better if the oxygen and the hydrocarbon are well mixed as gases. If the liquid is not very volatile, only those molecules on the surface can react with the oxygen. Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbors and turn to a gas.
Provided the combustion is complete, all the hydrocarbons will burn with a blue flame. However, combustion tends to be less complete as the number of carbon atoms in the molecules rises. That means that the bigger the hydrocarbon, the more likely you are to get a

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Retrieved Text: The terpene synthase discovered in this study consists of the prenyltransferase (PT) domain that synthesizesthe 20-carbon linear compound (GGPP) and the terpene cyclase domain that transforms GGPP into a cyclized hydrocarbon. By domain swapping of the PT with that which synthesizes the 25-carbon compound (GFPP), another molecule was successfully obtained.
A research group at the University of Tokyo has discovered and described the function of a unique enzyme involved in the biosynthesis of terpene (terpenoid) natural products, and successfully altered its function by altering its structure so that the enzyme produces another molecule.
Terpenoids are natural products synthesized from five-carbon isoprene units as building blocks, and include pharmaceutically important compounds such as the anticancer drug paclitaxel and antimalarial agent artemisinin. Terpenoids are synthesized by plants, microorganisms, and animals with the aid of enzymes.
The research group of Assistant Professor Yudai Matsuda and Professor Ikuro Abe at Graduate School of Pharmaceutical Sciences, The University of Tokyo, has identified a new terpene synthase from filamentous fungi that synthesizes a diterpene (terpene consisting of 20 carbon atoms) hydrocarbon with a novel molecular architecture. It is notable that the enzyme has two distinct domains; one is the prenyltransferase (PT) domain synthesizing the 20-carbon linear compound (GGPP) from five-carbon isoprene units, and the other one is the terpene cyclase (TC) domain that cyclizes the linear substrate into the final product. Thus, the terpene synthase is just like the Chimera in Greek mythology as two enzymes are fused as a single protein.
Although several similar multitasking enzymes have been described prior to this study, an attempt

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Retrieved Text: Crude oil, as it is taken from the earth, is a very complex mixture of hydrocarbons.
As might be expected, the term hydrocarbon refers to the hydrogen and carbon atoms linked together and forming a majority of the individual molecules that are present. Having been transformed from living organisms being subject to heat and pressure over millions of years, the crude is termed to be an “organic” material. In addition to hydrogen and carbon, there are small amounts of other atomic elements that are present and mostly incorporated into the hydrocarbon molecules. The most common of these are nitrogen and sulfur. As part of the hydrocarbon, they are referred to as “hetero-” atoms. Heavier crude may also contain some inorganic materials such as nickel, vanadium, and iron, which are removed during refining.
Hydrocarbons form in an extraordinarily large number of configurations. They range in size from the simplest methane molecule, which contains one carbon atom and four hydrogens, to heavy asphaltic resins with structures that have not been fully mapped. Because we are dealing with mineral oil–based lubricants, we are interested in molecules of a size that fit into the range of approximately 15 to 95 carbon atoms long, corresponding roughly to a boiling range of about 300–700°C. In addition, as the number of carbon atoms in a molecule increase, the number of different ways that a molecule can be structured increases dramatically. Although many different arrangements of molecules may be imagined, for practical purposes, petroleum hydrocarbons are generally classified in a limited number of ways.
Consider the list

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: Scientists may possibly have found clues to what seems to be the path to forming life's building blocks in space.
Published in Nature Astronomy journal the new study reveals that lab experiments carried out by scientists to retrace the chemical steps leading to the creation of complex hydrocarbons in space, showing pathways to forming 2-D carbon-based nanostructures in a mix of heated gases. Scientists say their findings could help explain the presence of pyrene, which is a chemical compound known as a polycyclic aromatic hydrocarbon, and similar compounds in some meteorites.
Scientists explain that Pyrene has a molecular structure composed of 16 carbon atoms and 10 hydrogen atoms. Researchers found that the same heated chemical processes that give rise to the formation of pyrene are also relevant to combustion processes in vehicle engines, for example, and the formation of soot particles.
The latest study builds on earlier work that analyzed hydrocarbons with smaller molecular rings that have also been observed in space, including in Saturn's moon Titan - namely benzene and naphthalene.
Pyrene belongs to a family known as polycyclic aromatic hydrocarbons, or PAHs, that are estimated to account for about 20 percent of all carbon in our galaxy. PAHs are organic molecules that are composed of a sequence of fused molecular rings. To explore how these rings develop in space, scientists work to synthesize these molecules and other surrounding molecules known to exist in space.
For this study, researchers explored the chemical reactions stemming from a combination of a complex hydrocarbon known as the 4-phenanthrenyl radical, which has a molecular

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Retrieved Text: Olefin content is an important factor in fuel production. But what exactly are olefins? In short, they’re an unsaturated hydrocarbon. Of course, there’s more to the story than that alone. Read on as we take a closer look at olefins – where they come from, what they’re made up of and why they’re important.
Olefin is a compound comprising hydrogen and carbon, with at least one pair of carbon atoms. Those atoms are linked by a double bond, which – along with the hydrogen and carbon content – makes them an unsaturated hydrocarbon.
Also known as alkene, olefins can vary in the number of double bonds per molecule, making them mono-olefins, diolefins, triolefins and so forth. They can also be categorised as either cyclic or acyclic. Cyclic olefins have a double bond between carbon atoms which makes up a closed ring of compounds. On the other hand, acyclic olefins form an open-chain group.
Where do olefins come from?
One of the earliest processes where olefins were produced came in the early 1900s through thermal cracking. This technique uses high temperatures and high pressure to break up large hydrocarbons into smaller compounds. They can also be produced by other forms of cracking, such as hydrocracking and fluid catalytic cracking.
Both petrol and diesel contain several different hydrocarbon molecules. Paraffins, olefins and aromatics account form most hydrocarbons in petrol, while diesel is mostly paraffins, aromatics and naphthenes.
Paraffins can improve the ignition quality of fuels, but can have low-termperature resistance. On the other hand, aromatics have high octane numbers – meaning the fuel can

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Retrieved Text: SCIENCE WAR research has produced various CAUSE --> EFFECT models that help explain some events....such as some accidents and deaths.
Here we shall look at the EARTH hydrocarbon continuum that humans live within.
Let's a background view established.
The astrophysics galactic LOCAL REGION (Planet Earth) is an interesting test location. A distant astrophysics observer ....... would see the earth as an atomic structure. Thus viewed, we could consider the astrophysics view of EARTH LAB events as atomic/molecular data events. In particular, physical chemistry --> social chemistry.
Thus ... we see that humans and humans institutions are subsets embedded within the atomic / astrophysics continuum .... an EARTH LAB atomic/astrophysics existential space .... an EARTH LAB atomic /astrophysics spectrum containing a variety of elements including human daily activities and events. Here, we concern ourselves with the hydrocarbon bandwidth (with humanoids) within Nature's larger existential continuum.
Let's look at a specific EARTH LAB case.
The organic chemistry hydrocarbon molecular WAR for control of the social chemistry institutions in the world ..... recently accomplished the assassination of Hugo Chavez via cancer.
With Hugo Chavez Dead, Will Chavismo Also Die?
Supporters of the late Venezuelan President Hugo Chavez cry in front of the ... hospitalized-- a day after his death in March 6, 2013, in Caracas.
The periodic atomic table used atomic mass communications to clearly imply the carbon atom ordered DEATH of Hugh Chavez ...under the auspices of disease. Mass communications is television, radio, newspaper publishing, print and graphic arts, the INTERNET computer information network, etc. For scientists ..mass communications is REALLY atomic mass communications .... that is

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Retrieved Text: This article provides you the revision notes on Class 12 Chemistry: Chapter- Amines, to give you a quick glance of the chapter. These quick notes are prepared strictly according to the latest CBSE syllabus for Class 12th Chemistry.
Nitrogen atom of amines carries an unshared pair of electrons and is sp3 hybridised with pyramidal shape. Due to the presence of unshared pair of electrons, the angle C–N–E, (where E is C or H) is less than 109.5°.
In aromatic amines, the C‒N bond is slightly stronger due to the partial double bond character which arises as a result of delocalisation of lone pair of N with the benzene ring.
• 1° amine: One hydrogen atom of NH3 is replaced by an alkyl or aryl group.
• 2° amine: Two hydrogen atoms of NH3 are replaced by alkyl or aryl groups.
• 3° amine: All three hydrogen atoms of NH3 are replaced by alkyl or aryl groups.
• Aliphatic amines are named by prefixing an alkyl group to a mine, i.e., alkylamine.
• Secondary and tertiary amines, having two or more similar groups are named by adding prefix ‘di’ or ‘tri’ before the name of alkyl group.
• Aromatic amines are named as derivatives of the parent member, aniline (C6H5NH2).
• Aliphatic or aromatic amines are named by replacing ‘e’ in the end of the parent hydrocarbon by ‘amine’.
• Amines containing more than one amino groups at different positions in the parent chain, are named by specifying numbers to the carbon atoms bearing –NH2 groups along with attaching a suitable prefix such as di, tri, etc.

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Retrieved Text: Kitchenlink Gas System Sdn Bhd is a gas piping system supplier company. Our main office is located in Puchong, Selangor, Malaysia. The company has been serving the gas piping industry for many years. We aim to deliver the highest quality service to our customers. If you would like any more information on the services we offer, please do not hesitate to contact us.
Natural gas is a gas that occurs deep beneath the earth’s surface. Natural gas consists mainly of methane, a gas (or compound) with one carbon atom and four hydrogen atoms. Natural gas also contains small amounts of hydrocarbon liquids and non-hydrocarbon gases. Natural gas can be used as a fuel or to make materials and chemicals.
• LPG is a mixture of two flammable but nontoxic gases called propane and butane. It is colourless and odourless in its natural state.
• LPG is heavier than air, unlike natural gas, and thus will flow along floors and tend to settle in low spots, such as basement.

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Retrieved Text: To describe the bonding in benzene and the way typical reactions of benzene differ from those of the alkenes.
Next we consider a class of hydrocarbons with molecular formulas like those of unsaturated hydrocarbons, but which, unlike the alkenes, do not readily undergo addition reactions. These compounds comprise a distinct class, called aromatic hydrocarbons, with unique structures and properties. We start with the simplest of these compounds. Benzene (C6H6) is of great commercial importance, but it also has noteworthy health effects.
The formula C6H6 seems to indicate that benzene has a high degree of unsaturation. (Hexane, the saturated hydrocarbon with six carbon atoms has the formula C6H14—eight more hydrogen atoms than benzene.) However, despite the seeming low level of saturation, benzene is rather unreactive. It does not, for example, react readily with bromine, which, is a test for unsaturation.

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Retrieved Text: ACK’S FATHER LIKES REGULAR BUTTER, HIS OLDER sister has been putting olive oil on everything since returning from her summer in Italy, and his 82-year-old grandmother, who lives with them, insists on using margarine.
Also, recently, Jack’s mother started buying a lot of foods containing high levels of omega- 3 fats, because, she says, they are healthy.
as a backbone for the triglyceride molecule (Fig. 1).
Fatty acids are carboxylic acids with long hydrocarbon tails. The general structure for a fatty acid is RCOOH, where –COOH is a carboxyl group and R represents a hydrocarbon side-chain containing 3 to 19 carbon atoms. In a triglyceride, the ester bond is between the carboxyl group of each fatty acid and one of the three alcohol (–OH) groups of the glycerol backbone (Fig. 1).
Figure 1. Fats and oils, also called triglycerides, are esters composed of three fatty acid units joined to glycerol. The ester bonds are indicated in red.

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Retrieved Text: Hydrocarbons containing at least three carbon atoms and non-aromatic carbon-to-hydrogen bonds are converted into hydrocarbons containing a new carbon-to-carbon linkage and having a higher carbon to hydrogen ratio by heating with an hydrogen-accepting olefine and a proportion of iodine (or hydrogen iodide, alkyl iodides or other compound which liberates iodine under the reaction conditions) of at least 0.05 mol. per mol. of hydrocarbon to be converted at at least 300 DEG C. to effect carbonto-hydrogen bond cleavage in the hydrocarbon feed and convert the olefine to paraffin. Conversions which may be effected are dehydrogenation of alkanes or aralkanes, e.g. isobutane to isobutene, n-butane to butenes and butadiene, ethyl benzene to styrene, o-methyl ethyl benzene to o-methyl styrene, and n-butyl benzene to 4 - phenyl - butadiene - 1,3; dehydrocoupling, e.g. propylene to diallyl, isobutene to dimethallyl, toluene to dibenzyl and stilbene; dehydrocyclization often with aromatization, e.g. n-hexane to benzene, n-heptane to toluene, n-octane to m-xylene and ethyl benzene, 2,5-dimethyl hexane to p-xylene, hexadiene-1,3 to benzene, hexane-1 to cyclohexene, o-diethylbenzene to naphthalene, o-methyl propyl benzene to naphthalene, n-butyl benzene to naphthalene, 2,3-diethyl naphthalene to anthracene, butylcyclohexane to naphthalene, and butylcyclopentane to indene; and dehydrogenation, often with aromatization of hydroaromatic hydrocarbons, e.g. cyclohexane to cyclohexene and benzene, and methylcyclohexane to toluene. In the case of acyclic hydrocarbons containing a quaternary carbon atom, dealkylation and/or isomerization may occur, e.g. 2,2,5-trimethylhexane gives p- and m-xylenes. The olefine used should be such that the sum of the standard free energy change for the hydrogenation of the olefine to the corresponding paraffin

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Retrieved Text: (organic compound) An alicyclic hydrocarbon, C6H12, consisting of a ring of six carbon atoms; a volatile liquid.
Supplemental Details:Sponsor an extended definition for cyclohexane for as little as $10 per month. Click here to contact us.

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Retrieved Text: We have put together a list of words that are similar to PARAFFIN.
4 A waxy white or colorless solid hydrocarbon mixture used to make candles, wax paper, lubricants, and sealing materials. Also called paraffin wax.
5 Chemistry A member of the alkane series.
7 To saturate, impregnate, or coat with paraffin.
8 The collective name for compounds of the marsh-gas series which have the general formula CnH2n + 2—that is, two more than twice as many hydrogen atoms as carbon atoms.
9 Specifically, in com. and manufacturing, a substance obtained by the dry distillation of wood, peat, bituminous coal, wax, etc.

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: Fuels Noaloil - NoalOil S.p.A.
Transport diesel complies with EN 590 European emission standards.To meet these standards, Directive 2009/30/EC requires that diesel should have a maximum sulphur content of 10 PPM (parts per million) and the biological component (biodiesel) can be anything up to 7% by volume.
European standard EN 228 is the reference standard for premium unleaded petrol with an octane rating of 95. Directive 2003/17/EC establishes the main requirements, such as sulphur levels (below 10 ppm) and octane rating (above 95).
Used as fuel, known as LPG (liquefied petroleum gas) it is composed primarily of a hydrocarbon mixture (propane and butane) obtained by refining crude oil or from extracted natural gas. These hydrocarbons become liquid under high pressures.
Formed by 1 carbon atom and 4 hydrogen atoms, methane is a simple hydrocarbon whose chemical formula is CH4. The form used for road transport is CNG (Compressed Natural Gas), a mixture of methane, propane and butane stored at 220 bar.
NOALOIL HIGH-SPEED DIESEL is a road transport diesel fuel that can be used on all diesel, eco-diesel and turbocharged engines.

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Retrieved Text: It’s well understood by physicists that stars are responsible for building most of the abundance of elements heavier than helium, through nuclear fusion. Recent observations from LIGO and optical counterparts of neutron star collisions indicate that these processes, and not supernovae, may be responsible for constructing certain elements such as gold and platinum.
But another considerable mystery is how complex chemistry occurs in outer space - how do these elemental building blocks meet and form complex hydrocarbons, like those that seem to be required for carbon-based life?
Now, new experiments have looked at conditions similar to those in outer space to assess the feasibility of processes to form a complex hydrocarbon molecule, pyrene. The study was an international collaboration between experimentalists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), astronomers from the University of Hawaii at Manoa, and theoretical chemists to understand the chemical reactions at Florida International University. The study was published March 5, in Nature Astronomy.
Hydrocarbons can include a vast array of different chemical compounds, due to the rich chemistry made possible by the hydrogenic bonding; molecular rings can form to provide a huge range of substances, many of which are used by biological organisms. Examples that have been detected in space include benzene and naphthalene. Pyrene is a slightly more complex molecule, consisting of 16 carbon atoms and ten hydrogen atoms; you can view it as four rings of benzene fused together. These polycylic aromatic hydrocarbons (PAHs) are considered possible precursors for the origin of life, and they are associated with the

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Retrieved Text: A systematic study of the oxidation of a range of terminal diols is reported, employing the oxoammonium salt 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (4-NHAc-TEMPO+ BF4−) as the oxidant. For substrates bearing a hydrocarbon chain of seven carbon atoms or more, the sole product is the dialdehyde. A series of post-oxidation reactions have been performed showing that the product mixture resulting from the oxidation step can be taken on directly to a subsequent transformation. For diols containing four to six carbon atoms, the lactone product is the major product upon oxidation. In the case of 1,2-ethanediol and 1,3-propanediol, when using a 1 : 0.5 stoichiometric ratio of substrate to oxidant, the corresponding monoaldehyde is formed which reacts rapidly with further diol to yield the acetal product. This is of particular synthetic value given both the difficulty of their preparation using other approaches and also their potential application in further reaction chemistry.

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Retrieved Text: A fatty acid is a combination of a chain of carbon and hydrogen atoms, known as a hydrocarbon, and a particular acid group (-COOH). Three fatty-acid molecules combined with a glycerol form a triglyceride fat or oil.
While several varieties of fatty acid occur in nature, all belong in one of two categories—saturated or unsaturated. In a saturated fatty-acid molecule, all the carbon atoms in the chain are attached to two hydrogen atoms, the maximum amount. All the bonds between the carbon atoms in the chain are single electron bonds. An example of fat made of saturated fatty acids is butter.
Unsaturated fatty-acid molecules have one or more carbon atoms with only a single hydrogen atom attached. In these chains, one or more bonds between the carbon atoms are double. A molecule with one double bond is called monounsaturated, and two or more double bonds is called polyunsaturated. An example of unsaturated fat is vegetable oil.
Generally, fats consisting of saturated fatty acids are solid, and those made up of unsaturated molecules are liquid. An unsaturated fatty acid may be converted into saturated through a process called hydrogenation. While most modern diets are aimed at the reduction of fatty acids (fats), it is important to recognize that several of them, such as oleic, butyric, and palmitic acid, are important parts of the human diet. Another, linoleic acid, is absolutely essential to human life. It is an important part of a vital chemical reaction in the body, and is obtained solely through ingestion. It is found in corn, soybean, and

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: The results show that the preparation of high quality C5 petroleum resin is not only limited to the content of the three olefins, but also needs to be improved by using monoolefins. The copolymerization of pentadiene with isopentene in a certain proportion gives a narrow molecular weight distribution, light, good solubility, low bromine value and good stability of the polymer products, this is because the heterogeneous tertiary olefins in the polymerization reaction plays a role in chain transfer, the formation of stable tert-carbon cations reason. It also has the effect of terminating the polymerization reaction because it captures the HCl produced by the contact of AlCl3 with piperylene, thereby slowing the promoter of HCl. The equation produces high molecular weight, poorly soluble polymers.
With this improvement, the quality of C5 petroleum resin to mediate monoolefins is a number of mono-olefins containing tertiary carbon atoms. The greater the content of these mono-olefins, the better the solubility of the resin. The lower the monoolefin content, the harder the resin, the higher the molecular weight, the more insoluble polymer components.
In addition, the cyclopentene in C5 acts similarly to the aromatic hydrocarbon solvent and promotes the production of a polymer having a high melting point and being soluble. Another kind of comonomer is terpene compounds, such as α-pinene, β-pinene, limonene and β-phellandrene, which can increase the viscosity of the resin without affecting the softening point of the resin. The double-ring structure of the pinene is opened to act as a chain transfer agent from the two tertiary carbenes. They are more

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Retrieved Text: (Nanowerk News) Chemists at The Scripps Research Institute (TSRI) have developed a broadly useful technique for building new drug molecules and other chemical products.
The technique, reported March 9, 2015 as an Advance Online paper by the journal Nature ("Ligand-Enabled meta-C-H Activation Using a Transient Mediator"), is an improved, easier method for "meta-C-H activation," the attachment of a desired group of atoms to a particularly hard-to-reach position on the carbon backbone of an organic molecule.
"This method can be used for the synthesis of small quantities, for example to discover potential new drug compounds, and also for bulk manufacturing," said Jin-Quan Yu, the Frank and Bertha Hupp Professor of Chemistry at TSRI.
Yu's laboratory specializes in finding better ways to build organic molecules and has now published five such innovations in Nature or Science over the past year. These highly technical methods generally pass under the radar of popular science news, but academic and professional chemists have been adopting them enthusiastically, using them to develop next-generation drugs and other novel chemical products.
A better method for meta-C-H activation should be especially welcome, given the traditional difficulty of that feat.
C-H activation means breaking a bond between a carbon and a hydrogen atom--hydrogen atoms being the default attachments to carbons in simple hydrocarbon molecules--and replacing the hydrogen with something else. Usually that something else is a more reactive cluster of atoms called a functional group, which helps give the resulting molecule its desired properties.
Chemists who build molecules using C-H activations often use an existing functional group on a hydrocarbon to facilitate the

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Retrieved Text: Why Does Cholesterol Lower Membrane Permeability?
What Are the Functional Groups in Cholesterol?
Cholesterol fills such important roles that your body makes its own supply rather than depending on dietary sources. Two of its jobs -- making bile acids and creating the outer coating of cells -- rely on chemical structures in the cholesterol molecule called functional groups. While cholesterol is not soluble in water, within the molecule, one type of functional group is water-soluble and another is insoluble. It turns out this dual characteristic plays an essential role.
Molecules are made from atoms, which sometimes combine to form a specific group of atoms. These are called functional groups because they’re responsible for precise tasks in your body. Functional groups also define unique characteristics of a molecule. Cholesterol has two types of functional groups. The first one, called a hydrocarbon functional group, consists of atoms of hydrogen and carbon. In cholesterol, the hydrocarbons connect to form two different shapes -- rings and chains. The second group, called a hydroxyl group, contains one atom each of hydrogen and oxygen.
Four hydrocarbon rings form the middle of the molecule. This functional group is the same one found in steroid hormones synthesized from cholesterol. A chain of hydrocarbons extends from one side of the nucleus, creating a hydrocarbon tail. One hydroxyl group is connected to the opposite side of the nucleus. There is one important difference between the groups: Hydroxyl groups are soluble in water, while hydrocarbons are not water-soluble. A molecule that has soluble and insoluble regions is called amphipathic. This amphipathic

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Retrieved Text: three molecules of fatty acids.
Each fatty acid consists of a hydrocarbon chain with a carboxyl group at one end. The glycerol molecule has three hydroxyl groups, each able to interact with the carboxyl group of a fatty acid. Removal of a water molecule at each of the three positions forms a triglyceride.
The three fatty acids in a single fat molecule may be all alike (as shown here for tristearin) or they may be different.
They may contain as few as 4 carbon atoms or as many as 24.
Because fatty acids are synthesized from fragments containing two carbon atoms, the number of carbon atoms in the chain is almost always an even number.
In animal fats, 16-carbon (palmitic acid) and 18-carbon (stearic acid - shown here) fatty acids are the most common.
Some fatty acids have one or more double bonds between their carbon atoms. They are called unsaturated because they could hold more hydrogen atoms than they do.
Monounsaturated fats have a single double bond in their fatty acids.
Polyunsaturated fats, such as trilinolein shown here, have two or more.
Double bonds are rigid and those in natural fats introduce a kink in the molecule. This prevents the fatty acids from packing close together and as a result, unsaturated fats have a lower melting point than do saturated fats. Because most of them are liquid at room temperature, we call them oils. Corn oil, canola oil, cottonseed oil, peanut oil, and olive oil are common examples.
As this list suggests, plant fats tend to be unsaturated (therefore "oils"). Fats from such animals as

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Input Text: Read the passage below and choose the right answer to the following question (choices are Eric or Rita ):

The more carbon atoms a hydrocarbon has, the greater the number of isomers.


Eric has a hydrocarbon with 20 carbon atoms. Rita has a hydrocarbon with 35 carbon atoms. Whose hydrocarbon has fewer isomers Eric or Rita?

Target Text: Eric

#### Retrieved Documents ####

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Retrieved Text: A major class of organic compounds where carbon and hydrogen molecules are arranged in straight or branched chains. A type of hydrocarbon . Includes alkane s, alkene s, and alkyne s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where all of the carbon-carbon bonds are single bonds. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a double bond. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a triple bond. One of three major classes of aliphatic hydrocarbon s.
Molecules which are almost entirely carbon and hydrogen, but have had at least one chlorine atom introduced to them that has replaced one of their hydrogen atoms.
A hydrocarbon (molecule of carbon and hydrogen only) with 27 carbon atoms that is the parent structure of all mammalian steroid s.
Any of several enzyme s that put double bonds into the hydrocarbon areas of fatty acid s.
Any in a family of over 200 chlorinated organic chemicals (all heterocyclic hydrocarbons). The term is most commonly applied to a particular chemical, 2,3,7,8-tetrachlorodibenzo-paradioxin (2,3,7,8-TCDD, simply called TCDD), which is an impurity in the defoliant Agent Orange and in the pesticide 2,4,5-T (see auxin ). Dioxins are also produced when chlorinated materials such as plastics are burned. Dioxins are known to cause skin diseases (chloracne), birth defects, miscarriages, and cancer .
A

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Retrieved Text: Chapter L3 Section 4 Organic Compounds The Four Bonds of a Carbon Atom More than 90% of all compounds belong to a group called organic compounds. Organic compounds are covalent compounds composed of carbon-based molecules. Fuel, rubbing alcohol, sugar, cotton, paper and plastic belong to this group. All organic compounds contain carbon. Each carbon atom has four valence electrons so each carbon atom can make four bonds with four other atoms.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Carbon Backbones Structural formulas are models that are used to show how atoms in a molecule are connected. Each line represents a pair of electrons that form a covalent bond.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Many organic compounds are based on the types of carbon backbones shown below. Some compounds have hundreds or thousands of carbon atoms as part of their backbone.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Organic compounds may also contain hydrogen, oxygen, sulfur, nitrogen, and phosphorus. The next slide shows three models of carbon backbones.
Section 4 Organic Compounds Hydrocarbons and Other Organic Compounds Many organic compounds contain several kinds of atoms, but some contain only two. Organic compounds that contain only carbon and hydrogen are called hydrocarbons. There are three types of hydrocarbons: saturated hydrocarbons, unsaturated hydrocarbons, and aromatic hydrocarbons.
Chapter L3 Section 4 Organic Compounds Hydrocarbons, continued Saturated Hydrocarbons An alkane, or saturated hydrocarbon, is a hydrocarbon in which each carbon atom in the molecule shares a single bond with

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Retrieved Text: Any organic compound composed only of carbon and hydrogen.
Any organic compound composed only of carbon and hydrogen. Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.
Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.

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Retrieved Text: Crude oil, as it is taken from the earth, is a very complex mixture of hydrocarbons.
As might be expected, the term hydrocarbon refers to the hydrogen and carbon atoms linked together and forming a majority of the individual molecules that are present. Having been transformed from living organisms being subject to heat and pressure over millions of years, the crude is termed to be an “organic” material. In addition to hydrogen and carbon, there are small amounts of other atomic elements that are present and mostly incorporated into the hydrocarbon molecules. The most common of these are nitrogen and sulfur. As part of the hydrocarbon, they are referred to as “hetero-” atoms. Heavier crude may also contain some inorganic materials such as nickel, vanadium, and iron, which are removed during refining.
Hydrocarbons form in an extraordinarily large number of configurations. They range in size from the simplest methane molecule, which contains one carbon atom and four hydrogens, to heavy asphaltic resins with structures that have not been fully mapped. Because we are dealing with mineral oil–based lubricants, we are interested in molecules of a size that fit into the range of approximately 15 to 95 carbon atoms long, corresponding roughly to a boiling range of about 300–700°C. In addition, as the number of carbon atoms in a molecule increase, the number of different ways that a molecule can be structured increases dramatically. Although many different arrangements of molecules may be imagined, for practical purposes, petroleum hydrocarbons are generally classified in a limited number of ways.
Consider the list

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: Hydrocarbon, an organic chemical compound composed of carbon and hydrogen. Hydrocarbons may be gases, liquids, or solids. In nature, they are found mainly in plants, petroleum, natural gas, coal, and oil shale. Most burn readily and dissolve more readily in alcohol than in water. Some are toxic and some form an explosive mixture with air. Hydrocarbons are used as fuels and solvents and in the manufacture of industrial chemicals, explosives, plastics, synthetic rubber, dyes, drugs, and other products.
More than 100,000 hydrocarbons are known. The main reason there are so many of these compounds is that carbon atoms can unite in many different ways to form complex chain or ring frameworks. Different arrangements of atoms yield different molecules. For example, the formula C30 H62 (30 carbon atoms and 62 hydrogen atoms) represents 4,111,846,763 possible isomers—compounds whose molecules differ only in structure.
In chemistry, compounds closely related in structure to hydrocarbons are called hydrocarbon derivatives. Such compounds consist of carbon, hydrogen, and other elements, usually oxygen, nitrogen, chlorine, phosphorus, or sulfur. They are often named for the hydrocarbons to which they are most closely related. For example, the organic chloride compound most closely related to ethane is called ethyl chloride. Hydrocarbons and their derivatives form a large part of the subject matter of organic chemistry.
Hydrocarbons are divided into two main groups according to structure—aliphatic (or acyclic) hydrocarbons and cyclic hydrocarbons. They are further divided into groups of compounds having similar chemical properties. Members within a group are called homologs, and each complete group is called a homologous series. Neighboring

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Retrieved Text: The terpene synthase discovered in this study consists of the prenyltransferase (PT) domain that synthesizesthe 20-carbon linear compound (GGPP) and the terpene cyclase domain that transforms GGPP into a cyclized hydrocarbon. By domain swapping of the PT with that which synthesizes the 25-carbon compound (GFPP), another molecule was successfully obtained.
A research group at the University of Tokyo has discovered and described the function of a unique enzyme involved in the biosynthesis of terpene (terpenoid) natural products, and successfully altered its function by altering its structure so that the enzyme produces another molecule.
Terpenoids are natural products synthesized from five-carbon isoprene units as building blocks, and include pharmaceutically important compounds such as the anticancer drug paclitaxel and antimalarial agent artemisinin. Terpenoids are synthesized by plants, microorganisms, and animals with the aid of enzymes.
The research group of Assistant Professor Yudai Matsuda and Professor Ikuro Abe at Graduate School of Pharmaceutical Sciences, The University of Tokyo, has identified a new terpene synthase from filamentous fungi that synthesizes a diterpene (terpene consisting of 20 carbon atoms) hydrocarbon with a novel molecular architecture. It is notable that the enzyme has two distinct domains; one is the prenyltransferase (PT) domain synthesizing the 20-carbon linear compound (GGPP) from five-carbon isoprene units, and the other one is the terpene cyclase (TC) domain that cyclizes the linear substrate into the final product. Thus, the terpene synthase is just like the Chimera in Greek mythology as two enzymes are fused as a single protein.
Although several similar multitasking enzymes have been described prior to this study, an attempt

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Retrieved Text: This page deals briefly with the combustion of alkanes and cycloalkanes. In fact, there is very little difference between the two.
Complete combustion (given sufficient oxygen) of any hydrocarbon produces carbon dioxide and water. It is quite important that you can write properly balanced equations for these reactions, because they often come up as a part of thermochemistry calculations. Some are easier than others. For example, with alkanes, the ones with an even number of carbon atoms are marginally harder than those with an odd number!
With butane (C4H10), you can again balance the carbons and hydrogens as you write the equation down.
Counting the oxygens leads to a slight problem - with 13 on the right-hand side. The simple trick is to allow yourself to have "six-and-a-half" O2 molecules on the left.
The hydrocarbons become harder to ignite as the molecules get bigger. This is because the bigger molecules don't vaporize so easily - the reaction is much better if the oxygen and the hydrocarbon are well mixed as gases. If the liquid is not very volatile, only those molecules on the surface can react with the oxygen. Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbors and turn to a gas.
Provided the combustion is complete, all the hydrocarbons will burn with a blue flame. However, combustion tends to be less complete as the number of carbon atoms in the molecules rises. That means that the bigger the hydrocarbon, the more likely you are to get a

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Retrieved Text: Hydrocarbons containing at least three carbon atoms and non-aromatic carbon-to-hydrogen bonds are converted into hydrocarbons containing a new carbon-to-carbon linkage and having a higher carbon to hydrogen ratio by heating with an hydrogen-accepting olefine and a proportion of iodine (or hydrogen iodide, alkyl iodides or other compound which liberates iodine under the reaction conditions) of at least 0.05 mol. per mol. of hydrocarbon to be converted at at least 300 DEG C. to effect carbonto-hydrogen bond cleavage in the hydrocarbon feed and convert the olefine to paraffin. Conversions which may be effected are dehydrogenation of alkanes or aralkanes, e.g. isobutane to isobutene, n-butane to butenes and butadiene, ethyl benzene to styrene, o-methyl ethyl benzene to o-methyl styrene, and n-butyl benzene to 4 - phenyl - butadiene - 1,3; dehydrocoupling, e.g. propylene to diallyl, isobutene to dimethallyl, toluene to dibenzyl and stilbene; dehydrocyclization often with aromatization, e.g. n-hexane to benzene, n-heptane to toluene, n-octane to m-xylene and ethyl benzene, 2,5-dimethyl hexane to p-xylene, hexadiene-1,3 to benzene, hexane-1 to cyclohexene, o-diethylbenzene to naphthalene, o-methyl propyl benzene to naphthalene, n-butyl benzene to naphthalene, 2,3-diethyl naphthalene to anthracene, butylcyclohexane to naphthalene, and butylcyclopentane to indene; and dehydrogenation, often with aromatization of hydroaromatic hydrocarbons, e.g. cyclohexane to cyclohexene and benzene, and methylcyclohexane to toluene. In the case of acyclic hydrocarbons containing a quaternary carbon atom, dealkylation and/or isomerization may occur, e.g. 2,2,5-trimethylhexane gives p- and m-xylenes. The olefine used should be such that the sum of the standard free energy change for the hydrogenation of the olefine to the corresponding paraffin

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Retrieved Text: Scientists may possibly have found clues to what seems to be the path to forming life's building blocks in space.
Published in Nature Astronomy journal the new study reveals that lab experiments carried out by scientists to retrace the chemical steps leading to the creation of complex hydrocarbons in space, showing pathways to forming 2-D carbon-based nanostructures in a mix of heated gases. Scientists say their findings could help explain the presence of pyrene, which is a chemical compound known as a polycyclic aromatic hydrocarbon, and similar compounds in some meteorites.
Scientists explain that Pyrene has a molecular structure composed of 16 carbon atoms and 10 hydrogen atoms. Researchers found that the same heated chemical processes that give rise to the formation of pyrene are also relevant to combustion processes in vehicle engines, for example, and the formation of soot particles.
The latest study builds on earlier work that analyzed hydrocarbons with smaller molecular rings that have also been observed in space, including in Saturn's moon Titan - namely benzene and naphthalene.
Pyrene belongs to a family known as polycyclic aromatic hydrocarbons, or PAHs, that are estimated to account for about 20 percent of all carbon in our galaxy. PAHs are organic molecules that are composed of a sequence of fused molecular rings. To explore how these rings develop in space, scientists work to synthesize these molecules and other surrounding molecules known to exist in space.
For this study, researchers explored the chemical reactions stemming from a combination of a complex hydrocarbon known as the 4-phenanthrenyl radical, which has a molecular

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: SCIENCE WAR research has produced various CAUSE --> EFFECT models that help explain some events....such as some accidents and deaths.
Here we shall look at the EARTH hydrocarbon continuum that humans live within.
Let's a background view established.
The astrophysics galactic LOCAL REGION (Planet Earth) is an interesting test location. A distant astrophysics observer ....... would see the earth as an atomic structure. Thus viewed, we could consider the astrophysics view of EARTH LAB events as atomic/molecular data events. In particular, physical chemistry --> social chemistry.
Thus ... we see that humans and humans institutions are subsets embedded within the atomic / astrophysics continuum .... an EARTH LAB atomic/astrophysics existential space .... an EARTH LAB atomic /astrophysics spectrum containing a variety of elements including human daily activities and events. Here, we concern ourselves with the hydrocarbon bandwidth (with humanoids) within Nature's larger existential continuum.
Let's look at a specific EARTH LAB case.
The organic chemistry hydrocarbon molecular WAR for control of the social chemistry institutions in the world ..... recently accomplished the assassination of Hugo Chavez via cancer.
With Hugo Chavez Dead, Will Chavismo Also Die?
Supporters of the late Venezuelan President Hugo Chavez cry in front of the ... hospitalized-- a day after his death in March 6, 2013, in Caracas.
The periodic atomic table used atomic mass communications to clearly imply the carbon atom ordered DEATH of Hugh Chavez ...under the auspices of disease. Mass communications is television, radio, newspaper publishing, print and graphic arts, the INTERNET computer information network, etc. For scientists ..mass communications is REALLY atomic mass communications .... that is

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Retrieved Text: Olefin content is an important factor in fuel production. But what exactly are olefins? In short, they’re an unsaturated hydrocarbon. Of course, there’s more to the story than that alone. Read on as we take a closer look at olefins – where they come from, what they’re made up of and why they’re important.
Olefin is a compound comprising hydrogen and carbon, with at least one pair of carbon atoms. Those atoms are linked by a double bond, which – along with the hydrogen and carbon content – makes them an unsaturated hydrocarbon.
Also known as alkene, olefins can vary in the number of double bonds per molecule, making them mono-olefins, diolefins, triolefins and so forth. They can also be categorised as either cyclic or acyclic. Cyclic olefins have a double bond between carbon atoms which makes up a closed ring of compounds. On the other hand, acyclic olefins form an open-chain group.
Where do olefins come from?
One of the earliest processes where olefins were produced came in the early 1900s through thermal cracking. This technique uses high temperatures and high pressure to break up large hydrocarbons into smaller compounds. They can also be produced by other forms of cracking, such as hydrocracking and fluid catalytic cracking.
Both petrol and diesel contain several different hydrocarbon molecules. Paraffins, olefins and aromatics account form most hydrocarbons in petrol, while diesel is mostly paraffins, aromatics and naphthenes.
Paraffins can improve the ignition quality of fuels, but can have low-termperature resistance. On the other hand, aromatics have high octane numbers – meaning the fuel can

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Retrieved Text: ACK’S FATHER LIKES REGULAR BUTTER, HIS OLDER sister has been putting olive oil on everything since returning from her summer in Italy, and his 82-year-old grandmother, who lives with them, insists on using margarine.
Also, recently, Jack’s mother started buying a lot of foods containing high levels of omega- 3 fats, because, she says, they are healthy.
as a backbone for the triglyceride molecule (Fig. 1).
Fatty acids are carboxylic acids with long hydrocarbon tails. The general structure for a fatty acid is RCOOH, where –COOH is a carboxyl group and R represents a hydrocarbon side-chain containing 3 to 19 carbon atoms. In a triglyceride, the ester bond is between the carboxyl group of each fatty acid and one of the three alcohol (–OH) groups of the glycerol backbone (Fig. 1).
Figure 1. Fats and oils, also called triglycerides, are esters composed of three fatty acid units joined to glycerol. The ester bonds are indicated in red.

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Retrieved Text: This article provides you the revision notes on Class 12 Chemistry: Chapter- Amines, to give you a quick glance of the chapter. These quick notes are prepared strictly according to the latest CBSE syllabus for Class 12th Chemistry.
Nitrogen atom of amines carries an unshared pair of electrons and is sp3 hybridised with pyramidal shape. Due to the presence of unshared pair of electrons, the angle C–N–E, (where E is C or H) is less than 109.5°.
In aromatic amines, the C‒N bond is slightly stronger due to the partial double bond character which arises as a result of delocalisation of lone pair of N with the benzene ring.
• 1° amine: One hydrogen atom of NH3 is replaced by an alkyl or aryl group.
• 2° amine: Two hydrogen atoms of NH3 are replaced by alkyl or aryl groups.
• 3° amine: All three hydrogen atoms of NH3 are replaced by alkyl or aryl groups.
• Aliphatic amines are named by prefixing an alkyl group to a mine, i.e., alkylamine.
• Secondary and tertiary amines, having two or more similar groups are named by adding prefix ‘di’ or ‘tri’ before the name of alkyl group.
• Aromatic amines are named as derivatives of the parent member, aniline (C6H5NH2).
• Aliphatic or aromatic amines are named by replacing ‘e’ in the end of the parent hydrocarbon by ‘amine’.
• Amines containing more than one amino groups at different positions in the parent chain, are named by specifying numbers to the carbon atoms bearing –NH2 groups along with attaching a suitable prefix such as di, tri, etc.

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Retrieved Text: (organic compound) An alicyclic hydrocarbon, C6H12, consisting of a ring of six carbon atoms; a volatile liquid.
Supplemental Details:Sponsor an extended definition for cyclohexane for as little as $10 per month. Click here to contact us.

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Retrieved Text: Kitchenlink Gas System Sdn Bhd is a gas piping system supplier company. Our main office is located in Puchong, Selangor, Malaysia. The company has been serving the gas piping industry for many years. We aim to deliver the highest quality service to our customers. If you would like any more information on the services we offer, please do not hesitate to contact us.
Natural gas is a gas that occurs deep beneath the earth’s surface. Natural gas consists mainly of methane, a gas (or compound) with one carbon atom and four hydrogen atoms. Natural gas also contains small amounts of hydrocarbon liquids and non-hydrocarbon gases. Natural gas can be used as a fuel or to make materials and chemicals.
• LPG is a mixture of two flammable but nontoxic gases called propane and butane. It is colourless and odourless in its natural state.
• LPG is heavier than air, unlike natural gas, and thus will flow along floors and tend to settle in low spots, such as basement.

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Retrieved Text: To describe the bonding in benzene and the way typical reactions of benzene differ from those of the alkenes.
Next we consider a class of hydrocarbons with molecular formulas like those of unsaturated hydrocarbons, but which, unlike the alkenes, do not readily undergo addition reactions. These compounds comprise a distinct class, called aromatic hydrocarbons, with unique structures and properties. We start with the simplest of these compounds. Benzene (C6H6) is of great commercial importance, but it also has noteworthy health effects.
The formula C6H6 seems to indicate that benzene has a high degree of unsaturation. (Hexane, the saturated hydrocarbon with six carbon atoms has the formula C6H14—eight more hydrogen atoms than benzene.) However, despite the seeming low level of saturation, benzene is rather unreactive. It does not, for example, react readily with bromine, which, is a test for unsaturation.

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Retrieved Text: Fuels Noaloil - NoalOil S.p.A.
Transport diesel complies with EN 590 European emission standards.To meet these standards, Directive 2009/30/EC requires that diesel should have a maximum sulphur content of 10 PPM (parts per million) and the biological component (biodiesel) can be anything up to 7% by volume.
European standard EN 228 is the reference standard for premium unleaded petrol with an octane rating of 95. Directive 2003/17/EC establishes the main requirements, such as sulphur levels (below 10 ppm) and octane rating (above 95).
Used as fuel, known as LPG (liquefied petroleum gas) it is composed primarily of a hydrocarbon mixture (propane and butane) obtained by refining crude oil or from extracted natural gas. These hydrocarbons become liquid under high pressures.
Formed by 1 carbon atom and 4 hydrogen atoms, methane is a simple hydrocarbon whose chemical formula is CH4. The form used for road transport is CNG (Compressed Natural Gas), a mixture of methane, propane and butane stored at 220 bar.
NOALOIL HIGH-SPEED DIESEL is a road transport diesel fuel that can be used on all diesel, eco-diesel and turbocharged engines.

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: We have put together a list of words that are similar to PARAFFIN.
4 A waxy white or colorless solid hydrocarbon mixture used to make candles, wax paper, lubricants, and sealing materials. Also called paraffin wax.
5 Chemistry A member of the alkane series.
7 To saturate, impregnate, or coat with paraffin.
8 The collective name for compounds of the marsh-gas series which have the general formula CnH2n + 2—that is, two more than twice as many hydrogen atoms as carbon atoms.
9 Specifically, in com. and manufacturing, a substance obtained by the dry distillation of wood, peat, bituminous coal, wax, etc.

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Retrieved Text: It’s well understood by physicists that stars are responsible for building most of the abundance of elements heavier than helium, through nuclear fusion. Recent observations from LIGO and optical counterparts of neutron star collisions indicate that these processes, and not supernovae, may be responsible for constructing certain elements such as gold and platinum.
But another considerable mystery is how complex chemistry occurs in outer space - how do these elemental building blocks meet and form complex hydrocarbons, like those that seem to be required for carbon-based life?
Now, new experiments have looked at conditions similar to those in outer space to assess the feasibility of processes to form a complex hydrocarbon molecule, pyrene. The study was an international collaboration between experimentalists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), astronomers from the University of Hawaii at Manoa, and theoretical chemists to understand the chemical reactions at Florida International University. The study was published March 5, in Nature Astronomy.
Hydrocarbons can include a vast array of different chemical compounds, due to the rich chemistry made possible by the hydrogenic bonding; molecular rings can form to provide a huge range of substances, many of which are used by biological organisms. Examples that have been detected in space include benzene and naphthalene. Pyrene is a slightly more complex molecule, consisting of 16 carbon atoms and ten hydrogen atoms; you can view it as four rings of benzene fused together. These polycylic aromatic hydrocarbons (PAHs) are considered possible precursors for the origin of life, and they are associated with the

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Retrieved Text: A systematic study of the oxidation of a range of terminal diols is reported, employing the oxoammonium salt 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (4-NHAc-TEMPO+ BF4−) as the oxidant. For substrates bearing a hydrocarbon chain of seven carbon atoms or more, the sole product is the dialdehyde. A series of post-oxidation reactions have been performed showing that the product mixture resulting from the oxidation step can be taken on directly to a subsequent transformation. For diols containing four to six carbon atoms, the lactone product is the major product upon oxidation. In the case of 1,2-ethanediol and 1,3-propanediol, when using a 1 : 0.5 stoichiometric ratio of substrate to oxidant, the corresponding monoaldehyde is formed which reacts rapidly with further diol to yield the acetal product. This is of particular synthetic value given both the difficulty of their preparation using other approaches and also their potential application in further reaction chemistry.

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Retrieved Text: A fatty acid is a combination of a chain of carbon and hydrogen atoms, known as a hydrocarbon, and a particular acid group (-COOH). Three fatty-acid molecules combined with a glycerol form a triglyceride fat or oil.
While several varieties of fatty acid occur in nature, all belong in one of two categories—saturated or unsaturated. In a saturated fatty-acid molecule, all the carbon atoms in the chain are attached to two hydrogen atoms, the maximum amount. All the bonds between the carbon atoms in the chain are single electron bonds. An example of fat made of saturated fatty acids is butter.
Unsaturated fatty-acid molecules have one or more carbon atoms with only a single hydrogen atom attached. In these chains, one or more bonds between the carbon atoms are double. A molecule with one double bond is called monounsaturated, and two or more double bonds is called polyunsaturated. An example of unsaturated fat is vegetable oil.
Generally, fats consisting of saturated fatty acids are solid, and those made up of unsaturated molecules are liquid. An unsaturated fatty acid may be converted into saturated through a process called hydrogenation. While most modern diets are aimed at the reduction of fatty acids (fats), it is important to recognize that several of them, such as oleic, butyric, and palmitic acid, are important parts of the human diet. Another, linoleic acid, is absolutely essential to human life. It is an important part of a vital chemical reaction in the body, and is obtained solely through ingestion. It is found in corn, soybean, and

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: (Nanowerk News) Chemists at The Scripps Research Institute (TSRI) have developed a broadly useful technique for building new drug molecules and other chemical products.
The technique, reported March 9, 2015 as an Advance Online paper by the journal Nature ("Ligand-Enabled meta-C-H Activation Using a Transient Mediator"), is an improved, easier method for "meta-C-H activation," the attachment of a desired group of atoms to a particularly hard-to-reach position on the carbon backbone of an organic molecule.
"This method can be used for the synthesis of small quantities, for example to discover potential new drug compounds, and also for bulk manufacturing," said Jin-Quan Yu, the Frank and Bertha Hupp Professor of Chemistry at TSRI.
Yu's laboratory specializes in finding better ways to build organic molecules and has now published five such innovations in Nature or Science over the past year. These highly technical methods generally pass under the radar of popular science news, but academic and professional chemists have been adopting them enthusiastically, using them to develop next-generation drugs and other novel chemical products.
A better method for meta-C-H activation should be especially welcome, given the traditional difficulty of that feat.
C-H activation means breaking a bond between a carbon and a hydrogen atom--hydrogen atoms being the default attachments to carbons in simple hydrocarbon molecules--and replacing the hydrogen with something else. Usually that something else is a more reactive cluster of atoms called a functional group, which helps give the resulting molecule its desired properties.
Chemists who build molecules using C-H activations often use an existing functional group on a hydrocarbon to facilitate the

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Retrieved Text: Why Does Cholesterol Lower Membrane Permeability?
What Are the Functional Groups in Cholesterol?
Cholesterol fills such important roles that your body makes its own supply rather than depending on dietary sources. Two of its jobs -- making bile acids and creating the outer coating of cells -- rely on chemical structures in the cholesterol molecule called functional groups. While cholesterol is not soluble in water, within the molecule, one type of functional group is water-soluble and another is insoluble. It turns out this dual characteristic plays an essential role.
Molecules are made from atoms, which sometimes combine to form a specific group of atoms. These are called functional groups because they’re responsible for precise tasks in your body. Functional groups also define unique characteristics of a molecule. Cholesterol has two types of functional groups. The first one, called a hydrocarbon functional group, consists of atoms of hydrogen and carbon. In cholesterol, the hydrocarbons connect to form two different shapes -- rings and chains. The second group, called a hydroxyl group, contains one atom each of hydrogen and oxygen.
Four hydrocarbon rings form the middle of the molecule. This functional group is the same one found in steroid hormones synthesized from cholesterol. A chain of hydrocarbons extends from one side of the nucleus, creating a hydrocarbon tail. One hydroxyl group is connected to the opposite side of the nucleus. There is one important difference between the groups: Hydroxyl groups are soluble in water, while hydrocarbons are not water-soluble. A molecule that has soluble and insoluble regions is called amphipathic. This amphipathic

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Retrieved Text: The results show that the preparation of high quality C5 petroleum resin is not only limited to the content of the three olefins, but also needs to be improved by using monoolefins. The copolymerization of pentadiene with isopentene in a certain proportion gives a narrow molecular weight distribution, light, good solubility, low bromine value and good stability of the polymer products, this is because the heterogeneous tertiary olefins in the polymerization reaction plays a role in chain transfer, the formation of stable tert-carbon cations reason. It also has the effect of terminating the polymerization reaction because it captures the HCl produced by the contact of AlCl3 with piperylene, thereby slowing the promoter of HCl. The equation produces high molecular weight, poorly soluble polymers.
With this improvement, the quality of C5 petroleum resin to mediate monoolefins is a number of mono-olefins containing tertiary carbon atoms. The greater the content of these mono-olefins, the better the solubility of the resin. The lower the monoolefin content, the harder the resin, the higher the molecular weight, the more insoluble polymer components.
In addition, the cyclopentene in C5 acts similarly to the aromatic hydrocarbon solvent and promotes the production of a polymer having a high melting point and being soluble. Another kind of comonomer is terpene compounds, such as α-pinene, β-pinene, limonene and β-phellandrene, which can increase the viscosity of the resin without affecting the softening point of the resin. The double-ring structure of the pinene is opened to act as a chain transfer agent from the two tertiary carbenes. They are more

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Retrieved Text: If a substance is hydrophobic, it does not dissolve in water. Lipids are hydrophobic because lipids are nonpolar molecules and water molecules are polar.
Lipids are a group of molecules that includes fats and oils, waxes, phospholipids, steroids (such as cholesterol) and other related compounds.
A polar molecule has two bonded atoms that do not share electrons. Polar molecules are only attracted to other polar molecules. Polar molecules are hydrophilic because they dissolve in water by forming hydrogen bonds.
Nonpolar molecules are not attracted to polar molecules and are called hydrophobic because they do not dissolve in water.
According to Carnegie Mellon, lipid molecules are hydrophobic because they consist of long, 18-22 carbon-hydrocarbon backbones and contain only a small amount of oxygen.
One type of lipids, called phospholipids, are amphipatic, that is, both hydrophillic and hydrophobic.

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Input Text: Read the passage below and choose the right answer to the following question (choices are more energy or less energy? ):

Bigger stars produce more energy, so their surfaces are hotter.


Compared to the Sun, which is an average sized star, would VY Canis Majoris, the largest known star, produce more energy or less energy??

Target Text: more energy

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Retrieved Text: VY Canis Majoris is a red hypergiant and an irregular pulsating variable star located in Canis Major. The star is one of the largest known in the Milky Way, and also one of the most luminous. It is estimated to be some 3,840 light years away. Unlike many stars, which are part of a multiple star system, VY Canis Majoris is a single star without any known companions.
Although in absolute magnitude VY Canis Majoris is extremely bright, its average apparent magnitude is 7.9 and peaks at 6.5, rendering it invisible to the unaided eye. The first mention of the star is in the star catalog of Jérôme Lalande, on March 7, 1801, as a 7th magnitude star. During the 19th century, additional observations revealed VY Canis Majoris was a red star and that it was fading over time. It is a semiregular variable star with a period of around 2,000 days.
In 1976, it was discovered that the star was located at the edge of a large molecular cloud. VY Canis Majoris itself was at the tip of the rim of the cloud and as they both share the same velocity, the star then may be associated with the cloud. Further measurements of the cloud in 2007 revealed it was prolific at creating compound molecules such as hydrogen cyanide (HCN), silicon monoxide (SiO), sodium chloride (NaCl) and phosphorus nitride (PN). The phosphorous molecules are the most interesting to astronomers, as phosphorous is relatively rare in the universe but an essential ingredient to life, as it is part

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Retrieved Text: Star greater than the Milky Way?
At a party a few days ago, I was standing outside with a couple of friends viewing the incredible night sky when we started talking about the magnificent vastness of space. One of them brought up having heard of a single star that was greater than the entire Milky Way galaxy – which is pretty freaking huge! I was skeptical, seeing as from what I know of stars there is a top limit of both mass and size, when the star will collapse onto itself, exploding into a supernova. Stars can be incredibly huge, but as large as the Milky Way, which itself contains several hundred billion stars?
Stars can indeed be pretty huge, but it’s impossible to keep track of the big numbers. The standing fact, I confirm after a few minutes of researching, is that while stars are huge, the galaxy is a lot huger. In the end it’s like comparing an A2 poster to North America – surely a poster can be pretty big, but an entire continent plays in a different league altogether.
Our own star, the Sun, is about 1 392 000 km in diameter, 109 times the size of the Earth. That’s a tad smaller than your random star in the universe, and there are lots of different kinds of stars both smaller and greater. Our Sun is very much a dwarf, and there are many stars that are several orders of magnitude larger. The greatest star discovered in the universe is VY Canis Majoris, a red

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Retrieved Text: There are times when we think too highly of ourselves. Perhaps there are even times when we think we are god in our own life.
Sometimes it is good to look at the bigger picture of God’s spoken creation and put our size into a bit of perspective!
Current data informs us that the visible universe contains an estimated 100 billion galaxies, each with a diameter millions of trillions of miles wide, and with each galaxy containing hundreds of billions of stars.
The universe is home to more than a billion trillion stars.
If one circled the earth seven times in one second, it would require at least 28 billion years to cross the universe at the same speed.
Our sun heats the earth and creates all the energy that drives our weather systems with only one-billionth of its energy.
One million earths would fit inside our sun.
The largest known star, VY Canis Majoris, can accommodate 9,200,000,000 of our suns.

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Retrieved Text: DZ Canis Majoris's star type is pulsating star that can be located in the constellation of Canis Major. The description is based on the spectral class.
DZ Canis Majoris is not part of the constellation outline but is within the borders of the constellation.
Based on the spectral type (G0 D~) of the star, the star's colour is white to yellow .
The star is calculated at being about 15385.06 light years away from us.
DZ Canis Majoris has alternative name(s) :- DZ CMa.
The location of the star in the night sky is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then its eastwards. The Declination is how far north or south the object is compared to the celestial equator and is expressed in degrees. For DZ Canis Majoris, the location is 07 16 59.3295830214 and -15 18 25.436502497 .
All stars like planets orbit round a central spot, in the case of planets, its the central star such as the Sun. In the case of a star, its the galactic centre. The constellations that we see today will be different than they were 50,000 years ago or 50,000 years from now. Proper Motion details the movements of these stars and are measured in milliarcseconds. The star is moving 1.98 miliarcseconds/year towards the north and -1.02 miliarcseconds/year east if we saw them in the horizon. . When

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Retrieved Text: Aludra, 31 Canis Majoris, CD−29°4328, FK5 283, HD 58350, HIP 35904, HR 2827, SAO 173651.
Eta Canis Majoris (η Canis Majoris, abbreviated Eta CMa, η CMa), also named Aludra, is a star in the constellation of Canis Major. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified.
η Canis Majoris (Latinised to Eta Canis Majoris) is the star's Bayer designation.
The traditional name Aludra originates from the Arabic: العذراء al-adhraa 'the virgin'. This star, along with Epsilon Canis Majoris (Adhara), Delta Canis Majoris (Wezen) and Omicron2 Canis Majoris (Thanih al Adzari), were Al ʽAdhārā (العذاري), 'the Virgins'. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 included a table of the first two batches of names approved by the WGSN; which included Aludra for this star.
Aludra shines brightly in the skies in spite of a large distance from Earth due to being intrinsically many times brighter than the Sun. A blue-white supergiant of spectral type B5Ia, Aludra has a luminosity 176,000 times and a diameter around 80 times that of the Sun. Hohle and colleagues, using the parallax, extinction and analysis of spectrum, came up with a mass 19.19 times that and luminosity 105,442 times that of the Sun. It has only been around a fraction of the time the Sun has, yet is already in the last stages of its life. It is still expanding

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Retrieved Text: The NASA/ESA Hubble Space Telescope still has a few tricks up its sleeve in its task of exploring the Universe. For one, it is able to image two adjacent parts of the sky simultaneously. It does this using two different cameras — one camera can be trained on the target object itself, and the other on a nearby patch of sky so that new and potentially interesting regions of the cosmos can be observed at the same time (these latter observations are known as parallel fields).
This image shows part of a bubble-like cloud of gas — a nebula named Sh2-308 — surrounding a massive and violent star named EZ Canis Majoris. It uses observations from Hubble’s Advanced Camera for Surveys, and is the parallel field associated with another view of the nebula produced by Hubble’s Wide Field Camera 3.
EZ Canis Majoris is something known as a Wolf-Rayet star, and is one of the brightest known stars of its kind. Its outer shell of hydrogen gas has been used up, revealing inner layers of heavier elements that burn at ferocious temperatures. The intense radiation pouring out from EZ Canis Majoris forms thick stellar winds that whip up nearby material, sculpting and blowing it outwards.
These processes have moulded the surrounding gas into a vast bubble. A bubble nebula produced by a Wolf-Rayet star is made of ionised hydrogen (HII), which is often found in interstellar space. In this case, it is the outer hydrogen layers of EZ Canis Majoris — the bubble — that are being inflated by

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Retrieved Text: On the search for beautiful star tattoos? The stars have brought you here. Stars do not just bring warmth and light to your cold and dark evenings; they are considered as a luminous sphere of plasma held together by its own gravity. Like stars, tattoos are a great way to put a sparkle of light in your life. They are good options to express yourself.
To know more about star tattoos, we have here a list of star tattoos that will capture your senses. They are easy to download and of high quality. They will surely provide you with a delightful outlook amid all the things and circumstances you’ve been through. Aside from them, there are also 3D Tattoo Designs, which are also of great quality and definition.
According to research, in our galaxy there are approximately 200–400 billion stars.
The closest celestial body of the star is the sun.
In terms of composition, stars are made of the same particles. They begin from being clouds of cold molecular hydrogen that gravitationally collapse.
The biggest pile of stars is considered as the red dwarfs. These are considered to be less than 50 percent the mass of the sun.
In terms of color, the color scheme range from red, white, and blue. In this color scheme, red is considered as the coolest color. Ironically, the hottest stars are the blue ones.
In terms of size, Betelgeuse weighs 20 times the mass of the sun. But the largest known star is the monster VY Canis Majoris. It is considered by researchers to be 1,800 times

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Retrieved Text: The Sirius satellite radios give you access to commercial free music and entertainment programming. Once you activate your subscription to Sirius, you are going to spend some time going through the different radio stations. After you find your favorite stations, you can begin setting up your presets.... Homer made much of it as [Kyon], but his Dog doubtless was limited to the star Sirius, as among the ancients generally till, at some unknown date, the constellation was formed as we have it, -- indeed till long afterwards, for we find many allusions to the Dog in which we are uncertain whether the constellation or its lucida is referred to.
Can' find how to download a sirius player to my computer?
Sirius, also known as the Dog Star, ? Canis Majoris (Alpha Canis Majoris), or Canicula, is the single brightest star in the night sky. It lies at a distance of 8.60 light years (2.64 parsecs) from Earth, in the constellation Canis Major, the Greater Dog.

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Retrieved Text: I know—not what you were expecting, was it? Well, like I mentioned in my last post, the brightest star in the sky is Sirius. It’s very far away from us. Proxima Centauri, on the other hand, is the nearest star to the sun…but it’s pretty dim, comparatively.
Fun Fact: Proxima Centauri is suspected to be part of a triple-star system also consisting of Alpha Centauri A and Alpha Centauri B. All three stars are gravitationally interlocked.
Proxima Centauri is the nearest of the three, making it the nearest star to the sun by a small margin.
We need to redefine the way we think about stars.
Think of stars as much like the sun. They are huge, exceedingly hot balls of gas whose gravity is so strong they drive their atoms to a breakneck frenzy.
I’ll talk more about stars and the way they produce heat in later posts—but for now, let’s just say that the hydrogen and helium gases that make up a star is so compressed and so excited that their atoms literally tear themselves apart.
That’s why stars are bright. They produce a ton of energy.
Anyway…because astronomers love labeling things in space, we have a way to describe the brightness of stars. Keep in mind that this only describes their apparent brightness—how they look to the human eye. Like I said, a star’s apparent brightness really has no bearing on its real brightness.
We use the magnitude scale.
This is a system that first appeared in the writings of the ancient astronomer Claudius Ptolemy. It’s likely the system actually originated earlier.

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Retrieved Text: Phecda (Gamma Ursae Majoris), the 6th brightest star in Ursa Major and 85th brightest star in the night sky, marks out the lower left corner of the Big Dipper’s bowl. Along with most of the Dipper’s stars, Phecda is an inner member of the Ursa Major Moving Group, which is a relatively large group of stars (which may include Sirius) that share a common proper motion across the sky.
Ursa Major and the 7 stars of its Big Dipper asterism are north circumpolar, making them visible the whole year round. Refer to the image above for the position of Phecda relative to the other stars in the Big Dipper.
Phecda has an Ae classification, with the “e” being an indication that the star is surrounded by a huge gas disc. It is also one of only 100 or so known Ae-type stars, all of which are rapid rotators. Phecda, for instance, spins with an equatorial rotational velocity of 178 km/sec compared to around 2 km/sec for the Sun.
In terms of its spectrum, Phecda is a white, so-called “colorless” star, which means that it has the same appearance when viewed optically, as it has in photographs. This effect is ascribed to the fact that Phecda is at the high end of the temperature range for A-class stars, which partially explains why Phecda behaves much like the much hotter B-class stars, which as a class, cools downwards from between 9,500K and 30,000K into the A-classification. As a rule, A-class stars do not exceed 9,500K.
Although Phecda is listed in several sources

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Retrieved Text: A supernova is a transient astronomical event that occurs during the last stellar evolutionary stages of a star's life, either a massive star or a white dwarf, whose destruction is marked by one final, titanic explosion. This causes the sudden appearance of a "new" bright star, before slowly fading from sight over several weeks or months or years.
A neutron star is the collapsed core of a large star which before collapse had a total of between 10 and 29 solar masses. Neutron stars are the smallest and densest stars, not counting hypothetical quark stars and strange stars. Typically, neutron stars have a radius on the order of 10 kilometres (6.2 mi) and a mass between 1.4 and 2.16 solar masses. They result from the supernova explosion of a massive star, combined with gravitational collapse, that compresses the core past the white dwarf star density to that of atomic nuclei. Once formed, they no longer actively generate heat, and cool over time; however, they may still evolve further through collision or accretion. Most of the basic models for these objects imply that neutron stars are composed almost entirely of neutrons ; the electrons and protons present in normal matter combine to produce neutrons at the conditions in a neutron star. Neutron stars are supported against further collapse by neutron degeneracy pressure, a phenomenon described by the Pauli exclusion principle, just as white dwarfs are supported against collapse by electron degeneracy pressure. If the remnant star has a mass greater than about 3 solar masses, it continues collapsing

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Retrieved Text: They are all really fascinating and impressive. We think sometimes we have to look at these pictures for understand ourselves!
This is our planet World! It’s where you live… Love the world because we have no other place for live!
4. North America Compared to Jupiter… A giant planet of gas!
5. And Six Worlds Compared to Saturn… Saturn is really huge planet!
6. If we had rings like Saturn Planet, It would look like this!
10. Size comparison of VJ Canis Majoris Star and Sun… It’s awesome difference!
12. Our Galaxy is big bur it’s not biggest! Milkway Galaxy is really small than LC 1011 Galaxy!
13. But there is much more Galaxies. Very much! Like the sand on the beach… Amazing!
14. It’s really very much! Another sample is small area near the Moon! This picture is so small part of big Universe!
Is There Anything That Is Faster Than Light?

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Retrieved Text: Wow, great find mortal, awesome stuff!
Water has been found on the moon! No wonder the aliens are up there.
Gigantic ring discovered around Saturn.
Martian Landscapes. Hi-res big pics.
I saw that on the news last night, they did a size comparison, that thing is huuuuge!
> comparison, that thing is huuuuge!
Really? I've been curious ever since I read about it, is it bigger than VY Canis Majoris??... For those who wonder VY Canis Majoris's diameter is as big as the whole solar system... Traveling aty speed of light could take as much as a day to get around... If this is bigger... WOW!!! No words!
Edited 3 time(s). Last edit at 07/23/2010 09:07AM by Slash.
one of the loudest human made sounds (i'm not responsible for accidentally blown speakers). you can even hear a car alarm going off.

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Retrieved Text: Humans have been naming the stars for millennia. The brightest stars were named long ago by people who immortalized their folklore in the heavens, and many of their names are still used today.
Centuries later, formal and systematic naming systems were developed when more extensive lists of stars were compiled.
The following sections describe in more detail how the stars received their names over the years.
You might have heard of some of the more popular stars, such as Sirius, Betelgeuse, and Polaris. These names sound foreign, and they are—their origins are mostly Arabic translations of Latin descriptions.
Common names. Credit: Starry Night software.
But to add to the confusion, scribes in the Middle Ages reproduced astronomical manuscripts by hand—a method that introduced errors, especially when copying words they did not know. Over time, the process of making copies of copies made it harder to decipher the original meaning of some words.
The common names for the brightest stars in the sky date back to ancient myths. Stars were often named after heroes, animals, or components of the constellations they helped form. The folklore of the stars offers a tantalizing glimpse into the associations ancient peoples established with the stars.
In all, about 900 stars have common names primarily of Arabic, Greek, or Latin origin. A few star names are relatively modern, however, invented as recently as the 20th century.
A few examples of common names are Sirius (Greek for scorching), Thuban (corrupted Arabic for serpent's head), and Betelgeuse, (a copying error from yad al-jauza, meaning the hand of al-Jauza, the "Central One").
Johann Bayer

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Retrieved Text: What is the Hawking Wave function of the Universe?
At what age could the Universe support Life?
Minimum speed of Vacuum metastability collapse?
How standard are supernovae type 1a standard candles?
Can someone explain this relativity paradox?
Were the Apollo astronauts prepared for encountering life?
Are there more than one kind of Wormhole, and what is the most plausable kind?
Can a Mercury sized moon support an atmosphere?
Does a "flat" universe imply an infinite universe?
Perihelion precession disparity for exoplanets?
Pangaea – just a myth?
APOD : Baryon Acoustic Oscillations from SDSS-III ? What ?
Stephen Hawking is now saying there are no black holes?
How does a planet lose heat?
A question about Newtonian gravity.
Moon visibility and the phases of the moon.
Just a wild theory about how the universe might have started.
What space mission has surpassed its designed mission time by the largest factor?
can we resolve a star?
Tidal heating of a locked planet?
Would oxygen burn on Titan?
What's needed to determine the temperature of the interior of the Sun?
Could we use Jupiter in a gravitational lensing telescope?
Total Solar Eclipse on August 21, 2017 - Is the max in Illinois or is it in Kentucky?
If other planets were as close as the moon?
Strange Jetted Asteroid With Multi Tails?
Digital 0/I Michelson Morley - Possible or Not ?
Is this is a good cosmological time-line?
Dark matter decay detected in xray frequencies?
What percentage of ISM metallicity is NOT due to supernovae?
Are there non-cosmic gamma rays in the Earth's atmosphere?
What is empty space made of ? What is the equation that describes it ?
GRB and a populated Solar system.
Could the atmosphere be a supercritical liquid

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Retrieved Text: The coffin was nondescript. Generic. A simple grey metal, no ID, no tracking beacon. Not even an inscription. “HUMAN REMAINS - BIOHAZARD - DO NOT OPEN.” Written in big block capitals. Leon stared at it. His father deserved more. He deserved his burial with the rest of his crew. He deserved a Federation flag and the 21 Guns and everything he had given to others. This was the best he could give. With an awkward push, Leon maneuvered the coffin towards the fore weapons loader access hatch.
VY Canis Majoris is the largest star visible from Earth. One of the largest known in the cluster. Leon settled back into the command chair of his Asp Explorer, Appaloosa. Dad was the one who had always inspired him with all those stories of knights and cowboys. He had suggested the names. Leon breathed a ragged breath, fighting to keep the tears down. He deployed the hardpoints.
“Warning: Non Standard Munitions Detected.” The computer droned. Leon almost laughed. His right hand brushed over and flicked some switches. “Override Accepted.” Then he pushed a button on the console. Soft music filled the cabin, an orchestral dirge from long ago. His father would’ve appreciated it. Leon pulled the trigger on the missile launcher.
The payload arced toward the star, on an arcing orbit. It would sail in through the corona and be reduced to plasma. Leon watched it fade from view, then as the blip on the scanner slowly became a signal ghost and then disappeared entirely.
“Bye, Dad.” He said placing his hand on

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Retrieved Text: Sunspots are places in the sun's atmosphere that are much cooler.
The photosphere is the visible layer of a star, most often brought up in discussions about the Sun. Though the Sun may appear to have a solid outer layer, just like the Earth, in truth it is made up of immensely hot gasses and has no solid surface. The photosphere marks the boundary where light can penetrate the gasses, allowing it to become less opaque and, thus, visible. What a person sees when he looks at the Sun is the photosphere.
The density of the atmospheric layer is not consistent in all places at all times, but tends to be about 248.5-310.6 miles (400-500 km) thick. The temperature ranges between 5,000 and 6,000 degrees Kelvin, or about 8,540-10,340 degrees Fahrenheit. It is the lowest layer of the Sun's atmosphere, sitting below the much thicker chromosphere and the enormous corona. Below the photosphere lie the Sun's convection and radiation zones, and beneath that, the mighty core.
When looking at the photosphere from far away, it may appear to be a simple yellow or orange disk with a few dark spots, known as sunspots. Up close, however, the photosphere has a textured appearance often referred to as granulated. While not necessarily pretty to look at, the bubbling texture of the photosphere is evidence of exactly how the sun works: the bubbles and knobs are signs of the process of convection. Convection on the sun works essentially the same way a boiling pot of water does; heated photons rise to the

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Retrieved Text: I am pursuing a dual-title Ph.D. in Astronomy & Astrobiology working with Professor Meadows on modeling exoplanet atmospheres. I continue development of a new 1D RCE climate model using the Virtual Planetary Laboratory‘s sophisticated SMART radiative transfer code. I primarily work on developing the convective routines, which include heat fluxes in unstable and stable atmospheres, phase changes, and cloud formation. I have been awarded a NASA Earth and Space Science Fellowship to implement a day/night heat transport structure and couple this model with the versatile KINETICS photochemistry code. These tools are used to model a variety of small planet atmospheres (particularly around M dwarfs) that may be very alien compared to Solar System planets. These models are also used to to predict spectral signatures of the modeled environments, and inform and assist with upcoming missions designed to characterize terrestrial exoplanets. The TRAPPIST-1 system is a target of particular interest and focus of my work.
During summer of 2015, I measured the pure rotational spectra of the four stable rare isotopologues of Titanium Monoxide (TiO) at the University of Arizona utilizing the Ziurys group direct absorption millimeter wave spectrometer and their Fourier Transform microwave spectrometer. This required melting or laser ablation of high purity titanium with the presence of oxygen to form vapor-phase TiO. This is relevant for astrophysics because TiO is a potential nucleation particle for the formation of interplanetary dust and in vapor phase has been measured around the red supergiant VY Canis Majoris.
During summer of 2014, I worked with Dr. Aki Roberge and Dr. Christopher

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Retrieved Text: Alpha Ursae Majoris (Latinised from α Ursae Majoris, abbreviated Alpha UMa, α UMa), also called Dubhe, is, despite being designated "α" (alpha), the second-brightest object in the constellation of Ursa Major.
Alpha Ursae Majoris forms part of the Big Dipper (also known as the Plough or the Great Bear), and is the northern of the 'pointers' (or 'guards'), the two stars of Ursa Major which point towards Polaris, the North Star.
α Ursae Majoris is about 123 light years from the Sun. It is a spectroscopic binary made up of the stars α Ursae Majoris A and α Ursae Majoris B. α Ursae Majoris A is the primary star, and it is a giant star that has evolved away from the main sequence after consuming the hydrogen at its core. The secondary star, α Ursae Majoris B, is a main sequence star that has a stellar classification of F0V. It orbits at a mean separation of about 23 astronomical units (AU) and completes an orbit every 44.4 years.
There is another spectroscopic binary 8 arcminutes distant, a 7th magnitude pair showing an F8 spectral type. It is sometimes referred to as Alpha Ursae Majoris C, but is separately catalogued as HD 95638.
α Ursae Majoris has been reported to vary in brightness by about a thousandth of a magnitude. Ten radial oscillation modes have been detected, with periods between 6.4 hours and 6.4 days.
Although it is part of the constellation of Ursa Major, it is not part of the Ursa Major Moving Group of stars that have a common motion

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Retrieved Text: 1. This is where you live. Earth.
2. This is our planetary neighborhood. Not to scale of course.
3. This is the distance between the Earth and the moon, to scale. Not too far right?
4. THINK AGAIN. Inside that distance you can fit every planet in our solar system!
5. That little green spot is North America on the planet Jupiter.
7. And just for funzies, here’s what Earth would look like if it had rings like Saturn.
8. This is a comet compared to the size of Los Angeles.
13. And from just beyond Neptune, 4 billion miles away.
14. Just a little reminder about the size of Earth vs the Sun.
16. There are more stars in space than there are grains of sand on every beach on Earth.
17. There are stars much, much bigger than our little sun. Just look at how tiny it is next this red hypergiant star located in the constellation Canis Majoris.
20. That is because the Milky Way Galaxy is HUGE. This is where we are in it all.
21. But the stars you see come from this small area.
Just THINK about what all could exist in there.
23. In this picture alone taken by the Hubble telescope, there are thousands and thousands of galaxies, each containing MILLIONS of stars, each with their own planets.
24. Here’s UDF 423, one of the galaxies pictured above. This galaxy is 10 BILLION light years away.
universe. A tiny fraction of the night sky.
26. If you think all that is intense, here’s the size of a black hole compared with Earth’s orbit.
So when you

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Retrieved Text: During this period the moon will reach its new phase on Wednesday November 7th. At this time the moon will be located near the sun and will be invisible at night. This weekend the waning crescent moon will rise during the early morning hours but will not cause any problems viewing meteors as long as you keep it out of your field of view. The estimated total hourly meteor rates for evening observers this week is near 4 for those viewing from the northern hemisphere and 3 for those located south of the equator. For morning observers the estimated total hourly rates should be near 24 as seen from mid-northern latitudes and 18 from the southern tropics. The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brighter meteors will be visible from such locations.
The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning November 3/4. These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions

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Retrieved Text: Scientists throughout the years have studied outer space immensely and still have many unanswered questions. They study the stars, moon, galaxies, black holes, and whatever else is found in the quiet, dark realm of space. As Christians, we look at the night sky and observe the moon and stars and think of how awesome a God we have. We see that there is no way that a big bang could have created such a scene, but only an Almighty God could have. Outer space is not really thought about very much by a person, but once one does think about it, his mind cannot comprehend the vastness of it. The region of space is truly an amazing part of God’s perfect creation.
Space is such a huge part of God’s creation, but it doesn’t get much recognition. When one talks about creation, how often do we think about the mountains, trees, flowers, and animals? One does not think much about outer space, even though it is so large. Just for a quick example of how big space is, the sun can fit 1,300,000 planet earths inside of it (Cool Cosmos). This is only the size of the sun!
There are also stars in outer space besides the sun called megastars. The closest megastar to Earth is called Pollux, which is 8.8 times larger than our sun. Next in line is Arcturus, which is 25.7 times the size of the sun. Another one of the known megastars is Antares. Antares is 883 times bigger than the sun! And the

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Retrieved Text: There are several canines in the night sky, including a wolf and a fox. But the best known canine constellations are Canis Major (the Greater Dog) and Canis Minor (the Lesser Dog).
There's been a dog constellation since the earliest days of Greek astronomy. It was called Kyon (the Dog). Then Kyon was joined by Prokyon (before the Dog), a constellation with only two stars. The brighter star Prokyon — now spelled Procyon — got its name because it rises before Sirius, The Dog Star, the brightest star of Canis Major.
2. Canis Major and Canis Minor are Orion's hunting dogs.
Around 150 AD Claudius Ptolemy listed the two dog constellations in his star catalog. Sometime later, Kyon became Canis Major and Prokyon became Canis Minor. There are some myths and stories about the two constellations, but for many centuries we've known them as Orion's hunting dogs.
3. Both constellations have one very bright star.
Sirius is not only the brightest star in Canis Major, but the brightest one in our night sky. Canis Minor's Procyon is the 8th brightest star we see.
The dogs are easy to spot if you first find Orion. Just follow the three stars of Orion's belt to the southeast. They point towards Sirius. Then Sirius and Procyon, along with Orion's red giant Betelgeuse, make the Winter Triangle.
5. Brightness matters, but distance matters more.
Procyon is eight times brighter than the Sun, and Sirius is over twenty times brighter. However almost all the other stars of Canis Major and Canis Minor are actually much brighter than Sirius and

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Retrieved Text: Alula Australis's star type is main sequence star that can be located in the constellation of Ursa Major. The description is based on the spectral class.
Alula Australis is not part of the constellation outline but is within the borders of the constellation.
Based on the spectral type (G0V) of the star, the star's colour is white to yellow .
Xi Ursae Majoris is the Bayer name for the star. It was assigned this name by Johann Bayer in 1603. The closer to the start of the Greek Alphabet the name, the brighter the star is. Alpha stars tend to be the brightest in the constellation. A notable exception is Pollux (Beta Geminorum) which is the brighest star in the Gemini constellation.
Alula Australis has alternative name(s) :- KSI UMa.
Flamsteed designations are named after the creator, Sir John Flamsteed. Sir John numbered the stars in the constellation with a number and the latin name, this star's Flamsteed designation is 53 Ursae Majoris with it shortened to 53 UMa.
BD number is the number that the star was filed under in the Durchmusterung or Bonner Durchmusterung, a star catalogue that was put together by the Bonn Observatory between 1859 to 1903. The star's BD Number is BD+32 2132.
The location of the main sequence star in the night sky is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then

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Retrieved Text: Manchester City entered the Football League in 1899, and won their first major honour with the FA Cup in 1904. It had its first major period of success in the late 1960s, winning the League, FA Cup and League Cup under the management of Joe Mercer and Malcolm Allison. After losing the 1981 FA Cup Final, the club went through a period of decline, culminating in relegation to the third tier of English football. Having regained their Premier League status in the early 2000s, Manchester City was purchased in 2008 by Abu Dhabi United Group for £210 million and received considerable financial investment.
New interesting posts: Winter Olympics Sports Clip Art, Gas Pump Clip Art Png, Blondie Live 2017, Resonance Waves, Rain Clip Art Black And White, Cracked Desert Ground, Vy Canis Majoris In The Night Sky, Green Lantern Movie Sinestro Ending, Voodoo Human Sacrifice.

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Retrieved Text: Mizar and Alcor are two stars forming a naked eye double in the handle of the Big Dipper (or Plough) asterism in the constellation of Ursa Major. Mizar is the second star from the end of the Big Dipper's handle, and Alcor its fainter companion. The traditional name Mizar derives from the Arabic المئزر miʼzar meaning 'apron; wrapper, covering, cover'. Alcor was originally Arabic سها‎ Suhā/Sohā, meaning either the ‘forgotten’ or ‘neglected’ one.; notable as a faintly perceptible companion of Mizar. Mizar, also designated Zeta Ursae Majoris (ζ Ursae Majoris, abbreviated Zeta UMa, ζ UMa), is itself a quadruple system and Alcor, also designated 80 Ursae Majoris (80 UMa), is a binary, the pair together forming a sextuple system. The whole system lies about 83 light-years away from the Sun, as measured by the Hipparcos astrometry satellite.
With normal eyesight Alcor appears at about 12 minutes of arc from Mizar. Alcor is of magnitude 3.99 and spectral class A5V. It has a faint red dwarf companion separated by 1 second of arc.
Mizar and Alcor's proper motions show they move together, along with most of the other stars of the Big Dipper except Dubhe and Alkaid, as members of the Ursa Major Moving Group, a mostly dispersed group of stars sharing a common birth. However, it has yet to be demonstrated conclusively that they are gravitationally bound. Recent studies indicate that the Alcor binary and Mizar quadruple are somewhat closer together than previously thought: approximately 74,000 ± 39,000 AU or 0.5–1.5 light years. The uncertainty is due to

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Retrieved Text: AB Andromedae's star type is eclipsing variable star that can be located in the constellation of Andromeda. The description is based on the spectral class.
AB Andromedae is not part of the constellation outline but is within the borders of the constellation.
Based on the spectral type (G5 + G5) of the star, the star's colour is white to yellow .
Using the most recent figures given by the 2007 Hipparcos data, the star is 344.42 light years away from us.
HIP114508 is the reference name for the star in the Hipparcos Star Catalogue.
AB Andromedae has alternative name(s) :- AB And, AB And.
BD number is the number that the star was filed under in the Durchmusterung or Bonner Durchmusterung, a star catalogue that was put together by the Bonn Observatory between 1859 to 1903. The star's BD Number is BD+36 5017.
The location of the variable star in the night sky is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then its eastwards. The Declination is how far north or south the object is compared to the celestial equator and is expressed in degrees. For AB Andromedae, the location is 23h 11m 32.01 and +36° 53` 35.6 .
All stars like planets orbit round a central spot, in the case of planets, its the central star such as the Sun. In the case of a star, its the

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Retrieved Text: Click here to receive the ALL THAT I CAN FIX Curriculum Guide, which includes activities and discussion questions.
Click here to download a press kit containing photos, bios, a synopsis of current work, and contact information.
Click here to download a BIRD Curriculum Guide, which includes activities and discussion questions.
The brightest star in a constellation is called the alpha, which is also the first letter of the Greek alphabet. The next brightest star is called beta. So Sirius, which is the brightest star in the sky, and which is located in the constellation Canis Major, the Great Dog, is called Alpha Canis Majoris.
Magnitude measures the brightness of stars. The brightest stars are called 1st magnitude, and second brightest are 2nd magnitude, and so on. Venus is so bright it has a negative magnitude of -4 magnitude!
The light from the nearest galaxy, Andromeda Galaxy, takes 2.6 million years to reach us. When you’re looking into space, you’re looking back in time.
The Perseids meteor shower can have as many as 80 meteors an hour. Some meteors have what seems like very short paths in the sky, and that is because they’re coming almost right at you.
The seasons have to do with the tilt of the earth’s axis, not how close/far away we are from the sun.
Asteroids are big rocks that orbit the sun. Some asteroids even have their own moons!
Jupiter is 318 times the size of the earth. And yet, it moves very fast, making one rotation in 9 hours, 55 minutes, 30 seconds. In fact, it rotates so fast

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Retrieved Text: In the second century, it was included in Ptolemy’s 48 constellations, and is counted among the 88 modern constellations.
Alpha Canis Majoris, known as sirius, is the brightest star in the night sky. The name “Sirius” is derived from the Ancient Greek Σείριος, meaning “glowing” or “scorcher”.
Preveza: At the entrance of Amvrakikos Gulf and in the shade of ancient Nikopolis is just 15 km. Walking through the city one observes the church of Saint Charalambos with Venetian clock, bust Karyotakis and other monuments. In the narrow streets of the central market there are fish restaurants, cafes, bars.
Arta: The haunted bridge. But the castle, the Byzantine churches of (Parigoritissa – Saint Theodora), the clock to give another reason to boast.
Lefkada: The history, beaches and events make ultimate destination for the summer.
Parga: Castles, rocky island, the church of Panagia, the rich vegetation and the beaches of the raise in classic beauty and value.
Small but beautiful. Operated environmental center.
The lagoons of Amvrakikos is of great natural beauty with rare species of birds.
The said “Pompeii” of D. Greece and is the largest archaeological site in Greece. The conservatory, theater, Byzantine walls, the Nymphaeum and basilicas deliver Nikopol eternity.
A river in Hades and lead the faithful to place him in contact with the dark underworld.
“The dance of Zalongo” eternal symbol of self-sacrifice (the sculptor Zongolopoulos work) are visible from the hotel.
Ruins of the city of the 4th B.C. are preserved near the village Kamarina.

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Retrieved Text: After examining the 5-million-year old star cluster NGC 2362, astronomers say that planets like Jupiter must form quickly because the material that form giant gas planets disappears in just few million years in young protoplanetary (planet forming) systems. Using NASA’s Spitzer Space Telescope, astronomers from the Smithsonian Center for Astrophysics found that all stars in this cluster with the mass of the Sun or greater have lost their protoplanetary disks, and only a few stars less massive than the Sun retain their protoplanetary disks. These disks provide the raw material for forming gas giants like Jupiter. Therefore, gas giant planets have to form in less than 5 million years or they probably won’t form at all. However, the material to form rocky terrestrial planets like Earth appears to stick around much longer.
“Even though astronomers have detected hundreds of Jupiter-mass planets around other stars, our results suggest that such planets must form extremely fast. Whatever process is responsible for forming Jupiters has to be incredibly efficient,” said lead researcher Thayne Currie of the Harvard-Smithsonian Center for Astrophysics. Currie presented the team’s findings at a meeting of the American Astronomical Society in Long Beach, California.
Even though nearly all gas giant-forming disks in NGC 2362 have disappeared, several stars in the cluster have “debris disks,” which indicates that smaller rocky or icy bodies such as Earth, Mars, or Pluto may still be forming.
“The Earth got going sooner, but Jupiter finished first, thanks to a big growth spurt,” explained co-author Scott Kenyon.
Kenyon added that while Earth took about 20 to

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Input Text: Read the passage below and choose the right answer to the following question (choices are more energy or less energy? ):

Bigger stars produce more energy, so their surfaces are hotter.


Compared to the Sun, which is an average sized star, would VY Canis Majoris, the smallest known star, produce more energy or less energy??

Target Text: less energy?

#### Retrieved Documents ####

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Retrieved Text: VY Canis Majoris is a red hypergiant and an irregular pulsating variable star located in Canis Major. The star is one of the largest known in the Milky Way, and also one of the most luminous. It is estimated to be some 3,840 light years away. Unlike many stars, which are part of a multiple star system, VY Canis Majoris is a single star without any known companions.
Although in absolute magnitude VY Canis Majoris is extremely bright, its average apparent magnitude is 7.9 and peaks at 6.5, rendering it invisible to the unaided eye. The first mention of the star is in the star catalog of Jérôme Lalande, on March 7, 1801, as a 7th magnitude star. During the 19th century, additional observations revealed VY Canis Majoris was a red star and that it was fading over time. It is a semiregular variable star with a period of around 2,000 days.
In 1976, it was discovered that the star was located at the edge of a large molecular cloud. VY Canis Majoris itself was at the tip of the rim of the cloud and as they both share the same velocity, the star then may be associated with the cloud. Further measurements of the cloud in 2007 revealed it was prolific at creating compound molecules such as hydrogen cyanide (HCN), silicon monoxide (SiO), sodium chloride (NaCl) and phosphorus nitride (PN). The phosphorous molecules are the most interesting to astronomers, as phosphorous is relatively rare in the universe but an essential ingredient to life, as it is part

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Retrieved Text: Star greater than the Milky Way?
At a party a few days ago, I was standing outside with a couple of friends viewing the incredible night sky when we started talking about the magnificent vastness of space. One of them brought up having heard of a single star that was greater than the entire Milky Way galaxy – which is pretty freaking huge! I was skeptical, seeing as from what I know of stars there is a top limit of both mass and size, when the star will collapse onto itself, exploding into a supernova. Stars can be incredibly huge, but as large as the Milky Way, which itself contains several hundred billion stars?
Stars can indeed be pretty huge, but it’s impossible to keep track of the big numbers. The standing fact, I confirm after a few minutes of researching, is that while stars are huge, the galaxy is a lot huger. In the end it’s like comparing an A2 poster to North America – surely a poster can be pretty big, but an entire continent plays in a different league altogether.
Our own star, the Sun, is about 1 392 000 km in diameter, 109 times the size of the Earth. That’s a tad smaller than your random star in the universe, and there are lots of different kinds of stars both smaller and greater. Our Sun is very much a dwarf, and there are many stars that are several orders of magnitude larger. The greatest star discovered in the universe is VY Canis Majoris, a red

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Retrieved Text: DZ Canis Majoris's star type is pulsating star that can be located in the constellation of Canis Major. The description is based on the spectral class.
DZ Canis Majoris is not part of the constellation outline but is within the borders of the constellation.
Based on the spectral type (G0 D~) of the star, the star's colour is white to yellow .
The star is calculated at being about 15385.06 light years away from us.
DZ Canis Majoris has alternative name(s) :- DZ CMa.
The location of the star in the night sky is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then its eastwards. The Declination is how far north or south the object is compared to the celestial equator and is expressed in degrees. For DZ Canis Majoris, the location is 07 16 59.3295830214 and -15 18 25.436502497 .
All stars like planets orbit round a central spot, in the case of planets, its the central star such as the Sun. In the case of a star, its the galactic centre. The constellations that we see today will be different than they were 50,000 years ago or 50,000 years from now. Proper Motion details the movements of these stars and are measured in milliarcseconds. The star is moving 1.98 miliarcseconds/year towards the north and -1.02 miliarcseconds/year east if we saw them in the horizon. . When

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Retrieved Text: Aludra, 31 Canis Majoris, CD−29°4328, FK5 283, HD 58350, HIP 35904, HR 2827, SAO 173651.
Eta Canis Majoris (η Canis Majoris, abbreviated Eta CMa, η CMa), also named Aludra, is a star in the constellation of Canis Major. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified.
η Canis Majoris (Latinised to Eta Canis Majoris) is the star's Bayer designation.
The traditional name Aludra originates from the Arabic: العذراء al-adhraa 'the virgin'. This star, along with Epsilon Canis Majoris (Adhara), Delta Canis Majoris (Wezen) and Omicron2 Canis Majoris (Thanih al Adzari), were Al ʽAdhārā (العذاري), 'the Virgins'. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016 included a table of the first two batches of names approved by the WGSN; which included Aludra for this star.
Aludra shines brightly in the skies in spite of a large distance from Earth due to being intrinsically many times brighter than the Sun. A blue-white supergiant of spectral type B5Ia, Aludra has a luminosity 176,000 times and a diameter around 80 times that of the Sun. Hohle and colleagues, using the parallax, extinction and analysis of spectrum, came up with a mass 19.19 times that and luminosity 105,442 times that of the Sun. It has only been around a fraction of the time the Sun has, yet is already in the last stages of its life. It is still expanding

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Retrieved Text: There are times when we think too highly of ourselves. Perhaps there are even times when we think we are god in our own life.
Sometimes it is good to look at the bigger picture of God’s spoken creation and put our size into a bit of perspective!
Current data informs us that the visible universe contains an estimated 100 billion galaxies, each with a diameter millions of trillions of miles wide, and with each galaxy containing hundreds of billions of stars.
The universe is home to more than a billion trillion stars.
If one circled the earth seven times in one second, it would require at least 28 billion years to cross the universe at the same speed.
Our sun heats the earth and creates all the energy that drives our weather systems with only one-billionth of its energy.
One million earths would fit inside our sun.
The largest known star, VY Canis Majoris, can accommodate 9,200,000,000 of our suns.

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Retrieved Text: The NASA/ESA Hubble Space Telescope still has a few tricks up its sleeve in its task of exploring the Universe. For one, it is able to image two adjacent parts of the sky simultaneously. It does this using two different cameras — one camera can be trained on the target object itself, and the other on a nearby patch of sky so that new and potentially interesting regions of the cosmos can be observed at the same time (these latter observations are known as parallel fields).
This image shows part of a bubble-like cloud of gas — a nebula named Sh2-308 — surrounding a massive and violent star named EZ Canis Majoris. It uses observations from Hubble’s Advanced Camera for Surveys, and is the parallel field associated with another view of the nebula produced by Hubble’s Wide Field Camera 3.
EZ Canis Majoris is something known as a Wolf-Rayet star, and is one of the brightest known stars of its kind. Its outer shell of hydrogen gas has been used up, revealing inner layers of heavier elements that burn at ferocious temperatures. The intense radiation pouring out from EZ Canis Majoris forms thick stellar winds that whip up nearby material, sculpting and blowing it outwards.
These processes have moulded the surrounding gas into a vast bubble. A bubble nebula produced by a Wolf-Rayet star is made of ionised hydrogen (HII), which is often found in interstellar space. In this case, it is the outer hydrogen layers of EZ Canis Majoris — the bubble — that are being inflated by

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Retrieved Text: The Sirius satellite radios give you access to commercial free music and entertainment programming. Once you activate your subscription to Sirius, you are going to spend some time going through the different radio stations. After you find your favorite stations, you can begin setting up your presets.... Homer made much of it as [Kyon], but his Dog doubtless was limited to the star Sirius, as among the ancients generally till, at some unknown date, the constellation was formed as we have it, -- indeed till long afterwards, for we find many allusions to the Dog in which we are uncertain whether the constellation or its lucida is referred to.
Can' find how to download a sirius player to my computer?
Sirius, also known as the Dog Star, ? Canis Majoris (Alpha Canis Majoris), or Canicula, is the single brightest star in the night sky. It lies at a distance of 8.60 light years (2.64 parsecs) from Earth, in the constellation Canis Major, the Greater Dog.

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Retrieved Text: I know—not what you were expecting, was it? Well, like I mentioned in my last post, the brightest star in the sky is Sirius. It’s very far away from us. Proxima Centauri, on the other hand, is the nearest star to the sun…but it’s pretty dim, comparatively.
Fun Fact: Proxima Centauri is suspected to be part of a triple-star system also consisting of Alpha Centauri A and Alpha Centauri B. All three stars are gravitationally interlocked.
Proxima Centauri is the nearest of the three, making it the nearest star to the sun by a small margin.
We need to redefine the way we think about stars.
Think of stars as much like the sun. They are huge, exceedingly hot balls of gas whose gravity is so strong they drive their atoms to a breakneck frenzy.
I’ll talk more about stars and the way they produce heat in later posts—but for now, let’s just say that the hydrogen and helium gases that make up a star is so compressed and so excited that their atoms literally tear themselves apart.
That’s why stars are bright. They produce a ton of energy.
Anyway…because astronomers love labeling things in space, we have a way to describe the brightness of stars. Keep in mind that this only describes their apparent brightness—how they look to the human eye. Like I said, a star’s apparent brightness really has no bearing on its real brightness.
We use the magnitude scale.
This is a system that first appeared in the writings of the ancient astronomer Claudius Ptolemy. It’s likely the system actually originated earlier.

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Retrieved Text: On the search for beautiful star tattoos? The stars have brought you here. Stars do not just bring warmth and light to your cold and dark evenings; they are considered as a luminous sphere of plasma held together by its own gravity. Like stars, tattoos are a great way to put a sparkle of light in your life. They are good options to express yourself.
To know more about star tattoos, we have here a list of star tattoos that will capture your senses. They are easy to download and of high quality. They will surely provide you with a delightful outlook amid all the things and circumstances you’ve been through. Aside from them, there are also 3D Tattoo Designs, which are also of great quality and definition.
According to research, in our galaxy there are approximately 200–400 billion stars.
The closest celestial body of the star is the sun.
In terms of composition, stars are made of the same particles. They begin from being clouds of cold molecular hydrogen that gravitationally collapse.
The biggest pile of stars is considered as the red dwarfs. These are considered to be less than 50 percent the mass of the sun.
In terms of color, the color scheme range from red, white, and blue. In this color scheme, red is considered as the coolest color. Ironically, the hottest stars are the blue ones.
In terms of size, Betelgeuse weighs 20 times the mass of the sun. But the largest known star is the monster VY Canis Majoris. It is considered by researchers to be 1,800 times

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Retrieved Text: Phecda (Gamma Ursae Majoris), the 6th brightest star in Ursa Major and 85th brightest star in the night sky, marks out the lower left corner of the Big Dipper’s bowl. Along with most of the Dipper’s stars, Phecda is an inner member of the Ursa Major Moving Group, which is a relatively large group of stars (which may include Sirius) that share a common proper motion across the sky.
Ursa Major and the 7 stars of its Big Dipper asterism are north circumpolar, making them visible the whole year round. Refer to the image above for the position of Phecda relative to the other stars in the Big Dipper.
Phecda has an Ae classification, with the “e” being an indication that the star is surrounded by a huge gas disc. It is also one of only 100 or so known Ae-type stars, all of which are rapid rotators. Phecda, for instance, spins with an equatorial rotational velocity of 178 km/sec compared to around 2 km/sec for the Sun.
In terms of its spectrum, Phecda is a white, so-called “colorless” star, which means that it has the same appearance when viewed optically, as it has in photographs. This effect is ascribed to the fact that Phecda is at the high end of the temperature range for A-class stars, which partially explains why Phecda behaves much like the much hotter B-class stars, which as a class, cools downwards from between 9,500K and 30,000K into the A-classification. As a rule, A-class stars do not exceed 9,500K.
Although Phecda is listed in several sources

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Retrieved Text: A supernova is a transient astronomical event that occurs during the last stellar evolutionary stages of a star's life, either a massive star or a white dwarf, whose destruction is marked by one final, titanic explosion. This causes the sudden appearance of a "new" bright star, before slowly fading from sight over several weeks or months or years.
A neutron star is the collapsed core of a large star which before collapse had a total of between 10 and 29 solar masses. Neutron stars are the smallest and densest stars, not counting hypothetical quark stars and strange stars. Typically, neutron stars have a radius on the order of 10 kilometres (6.2 mi) and a mass between 1.4 and 2.16 solar masses. They result from the supernova explosion of a massive star, combined with gravitational collapse, that compresses the core past the white dwarf star density to that of atomic nuclei. Once formed, they no longer actively generate heat, and cool over time; however, they may still evolve further through collision or accretion. Most of the basic models for these objects imply that neutron stars are composed almost entirely of neutrons ; the electrons and protons present in normal matter combine to produce neutrons at the conditions in a neutron star. Neutron stars are supported against further collapse by neutron degeneracy pressure, a phenomenon described by the Pauli exclusion principle, just as white dwarfs are supported against collapse by electron degeneracy pressure. If the remnant star has a mass greater than about 3 solar masses, it continues collapsing

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Score: 51.86617
Retrieved Text: They are all really fascinating and impressive. We think sometimes we have to look at these pictures for understand ourselves!
This is our planet World! It’s where you live… Love the world because we have no other place for live!
4. North America Compared to Jupiter… A giant planet of gas!
5. And Six Worlds Compared to Saturn… Saturn is really huge planet!
6. If we had rings like Saturn Planet, It would look like this!
10. Size comparison of VJ Canis Majoris Star and Sun… It’s awesome difference!
12. Our Galaxy is big bur it’s not biggest! Milkway Galaxy is really small than LC 1011 Galaxy!
13. But there is much more Galaxies. Very much! Like the sand on the beach… Amazing!
14. It’s really very much! Another sample is small area near the Moon! This picture is so small part of big Universe!
Is There Anything That Is Faster Than Light?

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Retrieved Text: Wow, great find mortal, awesome stuff!
Water has been found on the moon! No wonder the aliens are up there.
Gigantic ring discovered around Saturn.
Martian Landscapes. Hi-res big pics.
I saw that on the news last night, they did a size comparison, that thing is huuuuge!
> comparison, that thing is huuuuge!
Really? I've been curious ever since I read about it, is it bigger than VY Canis Majoris??... For those who wonder VY Canis Majoris's diameter is as big as the whole solar system... Traveling aty speed of light could take as much as a day to get around... If this is bigger... WOW!!! No words!
Edited 3 time(s). Last edit at 07/23/2010 09:07AM by Slash.
one of the loudest human made sounds (i'm not responsible for accidentally blown speakers). you can even hear a car alarm going off.

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Retrieved Text: Humans have been naming the stars for millennia. The brightest stars were named long ago by people who immortalized their folklore in the heavens, and many of their names are still used today.
Centuries later, formal and systematic naming systems were developed when more extensive lists of stars were compiled.
The following sections describe in more detail how the stars received their names over the years.
You might have heard of some of the more popular stars, such as Sirius, Betelgeuse, and Polaris. These names sound foreign, and they are—their origins are mostly Arabic translations of Latin descriptions.
Common names. Credit: Starry Night software.
But to add to the confusion, scribes in the Middle Ages reproduced astronomical manuscripts by hand—a method that introduced errors, especially when copying words they did not know. Over time, the process of making copies of copies made it harder to decipher the original meaning of some words.
The common names for the brightest stars in the sky date back to ancient myths. Stars were often named after heroes, animals, or components of the constellations they helped form. The folklore of the stars offers a tantalizing glimpse into the associations ancient peoples established with the stars.
In all, about 900 stars have common names primarily of Arabic, Greek, or Latin origin. A few star names are relatively modern, however, invented as recently as the 20th century.
A few examples of common names are Sirius (Greek for scorching), Thuban (corrupted Arabic for serpent's head), and Betelgeuse, (a copying error from yad al-jauza, meaning the hand of al-Jauza, the "Central One").
Johann Bayer

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Retrieved Text: Sunspots are places in the sun's atmosphere that are much cooler.
The photosphere is the visible layer of a star, most often brought up in discussions about the Sun. Though the Sun may appear to have a solid outer layer, just like the Earth, in truth it is made up of immensely hot gasses and has no solid surface. The photosphere marks the boundary where light can penetrate the gasses, allowing it to become less opaque and, thus, visible. What a person sees when he looks at the Sun is the photosphere.
The density of the atmospheric layer is not consistent in all places at all times, but tends to be about 248.5-310.6 miles (400-500 km) thick. The temperature ranges between 5,000 and 6,000 degrees Kelvin, or about 8,540-10,340 degrees Fahrenheit. It is the lowest layer of the Sun's atmosphere, sitting below the much thicker chromosphere and the enormous corona. Below the photosphere lie the Sun's convection and radiation zones, and beneath that, the mighty core.
When looking at the photosphere from far away, it may appear to be a simple yellow or orange disk with a few dark spots, known as sunspots. Up close, however, the photosphere has a textured appearance often referred to as granulated. While not necessarily pretty to look at, the bubbling texture of the photosphere is evidence of exactly how the sun works: the bubbles and knobs are signs of the process of convection. Convection on the sun works essentially the same way a boiling pot of water does; heated photons rise to the

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Retrieved Text: I am pursuing a dual-title Ph.D. in Astronomy & Astrobiology working with Professor Meadows on modeling exoplanet atmospheres. I continue development of a new 1D RCE climate model using the Virtual Planetary Laboratory‘s sophisticated SMART radiative transfer code. I primarily work on developing the convective routines, which include heat fluxes in unstable and stable atmospheres, phase changes, and cloud formation. I have been awarded a NASA Earth and Space Science Fellowship to implement a day/night heat transport structure and couple this model with the versatile KINETICS photochemistry code. These tools are used to model a variety of small planet atmospheres (particularly around M dwarfs) that may be very alien compared to Solar System planets. These models are also used to to predict spectral signatures of the modeled environments, and inform and assist with upcoming missions designed to characterize terrestrial exoplanets. The TRAPPIST-1 system is a target of particular interest and focus of my work.
During summer of 2015, I measured the pure rotational spectra of the four stable rare isotopologues of Titanium Monoxide (TiO) at the University of Arizona utilizing the Ziurys group direct absorption millimeter wave spectrometer and their Fourier Transform microwave spectrometer. This required melting or laser ablation of high purity titanium with the presence of oxygen to form vapor-phase TiO. This is relevant for astrophysics because TiO is a potential nucleation particle for the formation of interplanetary dust and in vapor phase has been measured around the red supergiant VY Canis Majoris.
During summer of 2014, I worked with Dr. Aki Roberge and Dr. Christopher

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Retrieved Text: Alpha Ursae Majoris (Latinised from α Ursae Majoris, abbreviated Alpha UMa, α UMa), also called Dubhe, is, despite being designated "α" (alpha), the second-brightest object in the constellation of Ursa Major.
Alpha Ursae Majoris forms part of the Big Dipper (also known as the Plough or the Great Bear), and is the northern of the 'pointers' (or 'guards'), the two stars of Ursa Major which point towards Polaris, the North Star.
α Ursae Majoris is about 123 light years from the Sun. It is a spectroscopic binary made up of the stars α Ursae Majoris A and α Ursae Majoris B. α Ursae Majoris A is the primary star, and it is a giant star that has evolved away from the main sequence after consuming the hydrogen at its core. The secondary star, α Ursae Majoris B, is a main sequence star that has a stellar classification of F0V. It orbits at a mean separation of about 23 astronomical units (AU) and completes an orbit every 44.4 years.
There is another spectroscopic binary 8 arcminutes distant, a 7th magnitude pair showing an F8 spectral type. It is sometimes referred to as Alpha Ursae Majoris C, but is separately catalogued as HD 95638.
α Ursae Majoris has been reported to vary in brightness by about a thousandth of a magnitude. Ten radial oscillation modes have been detected, with periods between 6.4 hours and 6.4 days.
Although it is part of the constellation of Ursa Major, it is not part of the Ursa Major Moving Group of stars that have a common motion

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Retrieved Text: 1. This is where you live. Earth.
2. This is our planetary neighborhood. Not to scale of course.
3. This is the distance between the Earth and the moon, to scale. Not too far right?
4. THINK AGAIN. Inside that distance you can fit every planet in our solar system!
5. That little green spot is North America on the planet Jupiter.
7. And just for funzies, here’s what Earth would look like if it had rings like Saturn.
8. This is a comet compared to the size of Los Angeles.
13. And from just beyond Neptune, 4 billion miles away.
14. Just a little reminder about the size of Earth vs the Sun.
16. There are more stars in space than there are grains of sand on every beach on Earth.
17. There are stars much, much bigger than our little sun. Just look at how tiny it is next this red hypergiant star located in the constellation Canis Majoris.
20. That is because the Milky Way Galaxy is HUGE. This is where we are in it all.
21. But the stars you see come from this small area.
Just THINK about what all could exist in there.
23. In this picture alone taken by the Hubble telescope, there are thousands and thousands of galaxies, each containing MILLIONS of stars, each with their own planets.
24. Here’s UDF 423, one of the galaxies pictured above. This galaxy is 10 BILLION light years away.
universe. A tiny fraction of the night sky.
26. If you think all that is intense, here’s the size of a black hole compared with Earth’s orbit.
So when you

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Retrieved Text: During this period the moon will reach its new phase on Wednesday November 7th. At this time the moon will be located near the sun and will be invisible at night. This weekend the waning crescent moon will rise during the early morning hours but will not cause any problems viewing meteors as long as you keep it out of your field of view. The estimated total hourly meteor rates for evening observers this week is near 4 for those viewing from the northern hemisphere and 3 for those located south of the equator. For morning observers the estimated total hourly rates should be near 24 as seen from mid-northern latitudes and 18 from the southern tropics. The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brighter meteors will be visible from such locations.
The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning November 3/4. These positions do not change greatly day to day so the listed coordinates may be used during this entire period. Most star atlases (available at science stores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions

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Retrieved Text: Scientists throughout the years have studied outer space immensely and still have many unanswered questions. They study the stars, moon, galaxies, black holes, and whatever else is found in the quiet, dark realm of space. As Christians, we look at the night sky and observe the moon and stars and think of how awesome a God we have. We see that there is no way that a big bang could have created such a scene, but only an Almighty God could have. Outer space is not really thought about very much by a person, but once one does think about it, his mind cannot comprehend the vastness of it. The region of space is truly an amazing part of God’s perfect creation.
Space is such a huge part of God’s creation, but it doesn’t get much recognition. When one talks about creation, how often do we think about the mountains, trees, flowers, and animals? One does not think much about outer space, even though it is so large. Just for a quick example of how big space is, the sun can fit 1,300,000 planet earths inside of it (Cool Cosmos). This is only the size of the sun!
There are also stars in outer space besides the sun called megastars. The closest megastar to Earth is called Pollux, which is 8.8 times larger than our sun. Next in line is Arcturus, which is 25.7 times the size of the sun. Another one of the known megastars is Antares. Antares is 883 times bigger than the sun! And the

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Retrieved Text: There are several canines in the night sky, including a wolf and a fox. But the best known canine constellations are Canis Major (the Greater Dog) and Canis Minor (the Lesser Dog).
There's been a dog constellation since the earliest days of Greek astronomy. It was called Kyon (the Dog). Then Kyon was joined by Prokyon (before the Dog), a constellation with only two stars. The brighter star Prokyon — now spelled Procyon — got its name because it rises before Sirius, The Dog Star, the brightest star of Canis Major.
2. Canis Major and Canis Minor are Orion's hunting dogs.
Around 150 AD Claudius Ptolemy listed the two dog constellations in his star catalog. Sometime later, Kyon became Canis Major and Prokyon became Canis Minor. There are some myths and stories about the two constellations, but for many centuries we've known them as Orion's hunting dogs.
3. Both constellations have one very bright star.
Sirius is not only the brightest star in Canis Major, but the brightest one in our night sky. Canis Minor's Procyon is the 8th brightest star we see.
The dogs are easy to spot if you first find Orion. Just follow the three stars of Orion's belt to the southeast. They point towards Sirius. Then Sirius and Procyon, along with Orion's red giant Betelgeuse, make the Winter Triangle.
5. Brightness matters, but distance matters more.
Procyon is eight times brighter than the Sun, and Sirius is over twenty times brighter. However almost all the other stars of Canis Major and Canis Minor are actually much brighter than Sirius and

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Retrieved Text: What is the Hawking Wave function of the Universe?
At what age could the Universe support Life?
Minimum speed of Vacuum metastability collapse?
How standard are supernovae type 1a standard candles?
Can someone explain this relativity paradox?
Were the Apollo astronauts prepared for encountering life?
Are there more than one kind of Wormhole, and what is the most plausable kind?
Can a Mercury sized moon support an atmosphere?
Does a "flat" universe imply an infinite universe?
Perihelion precession disparity for exoplanets?
Pangaea – just a myth?
APOD : Baryon Acoustic Oscillations from SDSS-III ? What ?
Stephen Hawking is now saying there are no black holes?
How does a planet lose heat?
A question about Newtonian gravity.
Moon visibility and the phases of the moon.
Just a wild theory about how the universe might have started.
What space mission has surpassed its designed mission time by the largest factor?
can we resolve a star?
Tidal heating of a locked planet?
Would oxygen burn on Titan?
What's needed to determine the temperature of the interior of the Sun?
Could we use Jupiter in a gravitational lensing telescope?
Total Solar Eclipse on August 21, 2017 - Is the max in Illinois or is it in Kentucky?
If other planets were as close as the moon?
Strange Jetted Asteroid With Multi Tails?
Digital 0/I Michelson Morley - Possible or Not ?
Is this is a good cosmological time-line?
Dark matter decay detected in xray frequencies?
What percentage of ISM metallicity is NOT due to supernovae?
Are there non-cosmic gamma rays in the Earth's atmosphere?
What is empty space made of ? What is the equation that describes it ?
GRB and a populated Solar system.
Could the atmosphere be a supercritical liquid

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Retrieved Text: Alula Australis's star type is main sequence star that can be located in the constellation of Ursa Major. The description is based on the spectral class.
Alula Australis is not part of the constellation outline but is within the borders of the constellation.
Based on the spectral type (G0V) of the star, the star's colour is white to yellow .
Xi Ursae Majoris is the Bayer name for the star. It was assigned this name by Johann Bayer in 1603. The closer to the start of the Greek Alphabet the name, the brighter the star is. Alpha stars tend to be the brightest in the constellation. A notable exception is Pollux (Beta Geminorum) which is the brighest star in the Gemini constellation.
Alula Australis has alternative name(s) :- KSI UMa.
Flamsteed designations are named after the creator, Sir John Flamsteed. Sir John numbered the stars in the constellation with a number and the latin name, this star's Flamsteed designation is 53 Ursae Majoris with it shortened to 53 UMa.
BD number is the number that the star was filed under in the Durchmusterung or Bonner Durchmusterung, a star catalogue that was put together by the Bonn Observatory between 1859 to 1903. The star's BD Number is BD+32 2132.
The location of the main sequence star in the night sky is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then

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Retrieved Text: The coffin was nondescript. Generic. A simple grey metal, no ID, no tracking beacon. Not even an inscription. “HUMAN REMAINS - BIOHAZARD - DO NOT OPEN.” Written in big block capitals. Leon stared at it. His father deserved more. He deserved his burial with the rest of his crew. He deserved a Federation flag and the 21 Guns and everything he had given to others. This was the best he could give. With an awkward push, Leon maneuvered the coffin towards the fore weapons loader access hatch.
VY Canis Majoris is the largest star visible from Earth. One of the largest known in the cluster. Leon settled back into the command chair of his Asp Explorer, Appaloosa. Dad was the one who had always inspired him with all those stories of knights and cowboys. He had suggested the names. Leon breathed a ragged breath, fighting to keep the tears down. He deployed the hardpoints.
“Warning: Non Standard Munitions Detected.” The computer droned. Leon almost laughed. His right hand brushed over and flicked some switches. “Override Accepted.” Then he pushed a button on the console. Soft music filled the cabin, an orchestral dirge from long ago. His father would’ve appreciated it. Leon pulled the trigger on the missile launcher.
The payload arced toward the star, on an arcing orbit. It would sail in through the corona and be reduced to plasma. Leon watched it fade from view, then as the blip on the scanner slowly became a signal ghost and then disappeared entirely.
“Bye, Dad.” He said placing his hand on

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Retrieved Text: Manchester City entered the Football League in 1899, and won their first major honour with the FA Cup in 1904. It had its first major period of success in the late 1960s, winning the League, FA Cup and League Cup under the management of Joe Mercer and Malcolm Allison. After losing the 1981 FA Cup Final, the club went through a period of decline, culminating in relegation to the third tier of English football. Having regained their Premier League status in the early 2000s, Manchester City was purchased in 2008 by Abu Dhabi United Group for £210 million and received considerable financial investment.
New interesting posts: Winter Olympics Sports Clip Art, Gas Pump Clip Art Png, Blondie Live 2017, Resonance Waves, Rain Clip Art Black And White, Cracked Desert Ground, Vy Canis Majoris In The Night Sky, Green Lantern Movie Sinestro Ending, Voodoo Human Sacrifice.

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Retrieved Text: Mizar and Alcor are two stars forming a naked eye double in the handle of the Big Dipper (or Plough) asterism in the constellation of Ursa Major. Mizar is the second star from the end of the Big Dipper's handle, and Alcor its fainter companion. The traditional name Mizar derives from the Arabic المئزر miʼzar meaning 'apron; wrapper, covering, cover'. Alcor was originally Arabic سها‎ Suhā/Sohā, meaning either the ‘forgotten’ or ‘neglected’ one.; notable as a faintly perceptible companion of Mizar. Mizar, also designated Zeta Ursae Majoris (ζ Ursae Majoris, abbreviated Zeta UMa, ζ UMa), is itself a quadruple system and Alcor, also designated 80 Ursae Majoris (80 UMa), is a binary, the pair together forming a sextuple system. The whole system lies about 83 light-years away from the Sun, as measured by the Hipparcos astrometry satellite.
With normal eyesight Alcor appears at about 12 minutes of arc from Mizar. Alcor is of magnitude 3.99 and spectral class A5V. It has a faint red dwarf companion separated by 1 second of arc.
Mizar and Alcor's proper motions show they move together, along with most of the other stars of the Big Dipper except Dubhe and Alkaid, as members of the Ursa Major Moving Group, a mostly dispersed group of stars sharing a common birth. However, it has yet to be demonstrated conclusively that they are gravitationally bound. Recent studies indicate that the Alcor binary and Mizar quadruple are somewhat closer together than previously thought: approximately 74,000 ± 39,000 AU or 0.5–1.5 light years. The uncertainty is due to

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Retrieved Text: AB Andromedae's star type is eclipsing variable star that can be located in the constellation of Andromeda. The description is based on the spectral class.
AB Andromedae is not part of the constellation outline but is within the borders of the constellation.
Based on the spectral type (G5 + G5) of the star, the star's colour is white to yellow .
Using the most recent figures given by the 2007 Hipparcos data, the star is 344.42 light years away from us.
HIP114508 is the reference name for the star in the Hipparcos Star Catalogue.
AB Andromedae has alternative name(s) :- AB And, AB And.
BD number is the number that the star was filed under in the Durchmusterung or Bonner Durchmusterung, a star catalogue that was put together by the Bonn Observatory between 1859 to 1903. The star's BD Number is BD+36 5017.
The location of the variable star in the night sky is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then its eastwards. The Declination is how far north or south the object is compared to the celestial equator and is expressed in degrees. For AB Andromedae, the location is 23h 11m 32.01 and +36° 53` 35.6 .
All stars like planets orbit round a central spot, in the case of planets, its the central star such as the Sun. In the case of a star, its the

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Retrieved Text: After examining the 5-million-year old star cluster NGC 2362, astronomers say that planets like Jupiter must form quickly because the material that form giant gas planets disappears in just few million years in young protoplanetary (planet forming) systems. Using NASA’s Spitzer Space Telescope, astronomers from the Smithsonian Center for Astrophysics found that all stars in this cluster with the mass of the Sun or greater have lost their protoplanetary disks, and only a few stars less massive than the Sun retain their protoplanetary disks. These disks provide the raw material for forming gas giants like Jupiter. Therefore, gas giant planets have to form in less than 5 million years or they probably won’t form at all. However, the material to form rocky terrestrial planets like Earth appears to stick around much longer.
“Even though astronomers have detected hundreds of Jupiter-mass planets around other stars, our results suggest that such planets must form extremely fast. Whatever process is responsible for forming Jupiters has to be incredibly efficient,” said lead researcher Thayne Currie of the Harvard-Smithsonian Center for Astrophysics. Currie presented the team’s findings at a meeting of the American Astronomical Society in Long Beach, California.
Even though nearly all gas giant-forming disks in NGC 2362 have disappeared, several stars in the cluster have “debris disks,” which indicates that smaller rocky or icy bodies such as Earth, Mars, or Pluto may still be forming.
“The Earth got going sooner, but Jupiter finished first, thanks to a big growth spurt,” explained co-author Scott Kenyon.
Kenyon added that while Earth took about 20 to

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Retrieved Text: Tonight we’ll use both Sirius and Beta Monocerotis as our guides to have a look at one fantastic galactic cluster for any optical aid – M50. Hop about a fistwidth east-southeast of Beta, or northeast of Sirius…and be prepared!
Perhaps discovered as early as 1711 by G. D. Cassini, it was relocated by Messier in 1772 and confirmed by J. E. Bode in 1774. Containing perhaps as many as 200 members, this colorful old cluster resides almost 3000 light-years away. The light of the stars you are looking at tonight left this cluster at a time when iron was first being smelted and used in tools. The Mayan culture was just beginning to develop, while the Hebrews and Phoenicians were creating an alphabet. Do you wonder if it looked the same then as it does now?
In binoculars you will see an almost heart-shaped collection of stars, while telescopes will begin to resolve out color and many fainter members – with a very notable red one in its midst. Enjoy this worthy cluster and make a note that you’ve captured another Messier object!
Tuesday, March 6 – If you get a chance to see sunshine today, then celebrate the birthday of Joseph Fraunhofer, who was born in 1787. As a German scientist, Fraunhofer was truly a “trailblazer” in terms of modern astronomy. His field? Spectroscopy!
After having served his apprenticeship as a lens and mirror maker, Fraunhofer went on to develop scientific instruments, specializing in applied optics. While designing the achromatic objective lens for the telescope, he was watching the

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Retrieved Text: This artist's conception compares the KOI-961 planetary system to Jupiter and the largest four of its many moons. The KOI-961 planetary system hosts the three smallest planets known to orbit a star beyond our sun (called KOI-961.01, KOI-961.02 and KOI-961.03). Image released January 11, 2011.
An artist's rendering of the newfound alien planet Kepler-20e, which scientists say is smaller than Earth, at about 0.87 times the width of our planet.
This illustration shows the alien planet Kepler-20f, discovered by NASA's Kepler space telescope. At 1.03 times the width of Earth, Kepler-20f is the second smallest exoplanet yet found.
The former champ of most Earth-sized planets yet is a world called Gliese 581 e, which circles a star that has four planets total. It was called the smallest because of its mass, which is just 1.9 times the mass of Earth, making it the lightest known alien planet at the time.
Artist's concept of Kepler-10b, which was detected by NASA's Kepler mission and is about 1.4 times the radius of Earth. Kepler scientists say it's the first "unquestionably rocky" alien planet ever found. It is about 560 light-years from Earth.
The star field studied by NASA's planet-hunting Kepler space telescope, as seen over southern Arizona's Kitt Peak National Observatory. The approximate position of the alien planet Kepler-21b and its parent star HD 179070 is indicated by the circle. Kepler-21b is located 352 light-years from Earth.
This artist's concept illustrates the two Saturn-sized planets discovered by NASA's Kepler mission around a star called Kepler-9. A 3rd planet, Kepler-9d just 1.5 times the radius of

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Input Text: Read the passage below and choose the right answer to the following question (choices are more or less ):

A sunscreen with a higher SPF value protects the skin longer.


A sunscreen with an SPF value of 15 will protect skin more or less than a sunscreen with an SPF value of 30?

Target Text: less

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Retrieved Text: to keep your skin safe is by wearing sunscreen.
It is now easier to protect your skin than ever before. All sunscreen lotion labels will soon get a face lift to make it easier for you to pick the right sunscreen. Next time you shop for a sunscreen, look for the new “broad spectrum” label on the package.
Broad spectrum means that a product can block UVA and UVB sun rays equally. UVA and UVB rays can cause skin cancer, early skin aging and sunburn. In the past, sunscreens mostly protected your skin from UVB rays that cause sunburns.
How Else are Labels Changing?
What Product is the Best for Me?
Everyone’s skin can benefit from sunscreen. Sunscreen that does not have a broad spectrum label will NOT protect you from skin cancer and early skin aging. These changes are only for sunscreen lotion and not spray because you put on spray sunscreens differently than lotions. For the best protection, follow these guidelines.
Use at least an SPF 15 up to an SPF 50. SPF stands for Sun Protection Factor or how much sun protection a product offers. The higher the SPF value of the sunscreen, the better protection it will offer. But this is only up to SPF 50. Sunscreens with an SPF greater than 50 still work, but it is unclear if they work any better than SPF 50 lotions.
Use broad spectrum sunscreen with an SPF of 15 or higher. Broad spectrum SPF 15 products can protect your skin against sunburn, skin cancer and early sun aging.
If swimming or sweating,

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Retrieved Text: What SPF sunblock should you buy, SPF 15, 30, 60 or greater?
Use of Sunblock creams or sunscreens is now popular amongst both male and female sexes. When you go to a dermatologist or cosmetician to have an opinion about better skin care management, they will tell you to use a sunblock whenever you go out in the sun. When you go to a shop to buy a sunscreen, you don’t know what SPF sunblock should you buy?. You fear that an SPF 15 sunblock is nothing in front of SPF 50 or 90 sunblock, then you also worry about the cost of a high SPF sunblock.
Sun rays contain ultraviolet radiations that have the tendency to damage your skin. Our skin has the ability to resist this damage for a few minutes to an hour depending upon the colour of the skin. Dark coloured individuals tend to withstand the sunlight for a longer period of time as compared to a fair coloured individual. White skinned individuals more commonly complain of sun damage, rash, pimples and acne as compared to dark skinned individuals.
Why do the dark colored individuals withstand sunlight better?
Cosmetologist encourages the use of sunblock in adults when they go out in the sun. When you buy a sunscreen or sunblock cream, you see a special value on the pack represented by SPF. You may see various values of SPF, maybe 15, 24, 30, 40, 45, 60 etc. SPF stands for sun protection factor. The higher the value better will be the protection. For instance, a 15

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Retrieved Text: Get ready Portland: summer is officially here. And just in time for summer, the Food and Drug Administration has unveiled new FDA sunscreen regulations. The new regulations will change how sunscreens are labeled, starting in summer of 2012.
According to Jill Lindstrom M.D., a dermatologist for the FDA, “We encourage consumers to use sunscreens that are labeled with a broad spectrum SPF value of at least 15.
Broad spectrum sunscreens protect from UVA rays (which cause skin aging) and UVB rays (which cause sunburns).
What Are The New FDA Sunscreen Regulations?
Starting in 2012, sunscreens cannot be labeled with an SPF value higher than SPF 50. Also, manufacturers will have to prove their broad spectrum protection claims.
The new sunscreen label rules will also change the labels of sunscreens that are sweat resistant or water resistant. Currently, the labels may say “waterproof” or “sweatproof.” According to the FDA, sunscreens lose effectiveness when wet and will need to be reapplied frequently.
The FDA also states that they have no reason to believe that currently available sunscreens are unsafe. Remember, protecting your skin from the sun now can help protect your skin from early skin aging. Photoaging is skin aging caused by the sun. It is a major cause of fine lines and wrinkles, as well as changes in skin tone and texture.
If you feel your skin is already showing the effects of photoaging, make an appointment to learn how the skin and surgical treatments we offer can improve the appearance of skin aging. It is important that you protect your skin from the

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Retrieved Text: What SPF sunscreen should I use?
Nicole needs to know…Is there a really big difference between using SPF 15 and SPF 30 facial moisturizer? If so, why? I was told to wear 30 in order to prevent rosacea flare ups.
Skin exposure to UV rays is almost never good for the skin. It causes sun burn, wrinkles, dryness, and as you’ve implied, rosacea flare ups. This is why the most important thing you can do for your skin is to wear a sunscreen or stay out of the sun. But what kind of sunscreen should you use?
Before answering this, we should first tell you what the SPF number means. SPF stands for sun protection factor and it essentially is a rating of how much UV light will be blocked. In general, a higher SPF number offers more protection from UV exposure than a lower number. How effective it is depends on many factors but the number one factor is your skin type. SPF 15 means that if you would normally burn after being in the sun for 20 minutes, you will be able to stay in the sun for 15 times as long or 5 hours. But it is important to note that the SPF scale is not a linear one. An SPF 2 will block 50% of the UV light while an SPF 15 will block 92% of all the UV light that reaches your skin and an SPF 34 blocks 97% of the UV light.
Although skin type is the number one factor is determining the effectiveness

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Retrieved Text: You can reduce the risk of getting skin cancer by protecting yourself and your children when you are in the sun. This means more than just wearing sunscreen on hot summer days. Up to 80% of the sun’s rays can reach you through light clouds, mist, and fog. You need to protect yourself even on cloudy days. Fresh snow reflects up to 95% of the sun’s rays, so remember to wear sunscreen in the snow. You can also get sunburned when you are in or on the water, so take precautions when you are swimming or boating.
Limit the amount of time you spend in the sun between the hours of 10 AM and 4 PM. This is when the sun’s rays are the strongest. Check the local UV index to see what kinds of sun protection you might need.
If you have to be in the sun, wear long pants and a long-sleeved shirt. Tightly woven, dark-colored fabrics give you more protection than light-colored, loosely woven clothes.
Use a broad-spectrum sunscreen every day that provides protection against both UV-A and UV-B ray with an SPF rating of 30 or higher. Apply liberally. As a general guideline, the portion you apply should roughly fill the cup of the palm of your hand.
Apply sunscreen at least 1/2 hour before you go into the sun. This allows the sunscreen to seep into the upper skin layers, giving you better protection.
Protect your lips with a lip balm that has an SPF of 15 or higher.
Reapply sunscreen (even waterproof sunscreen) every 2 hours,

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Retrieved Text: Is Makeup With Sunscreen Enough to Protect Your Skin?
Many foundations and powders contain sunscreen, but is it enough for daily protection?
You want to prevent wrinkles and skin cancer, so you are dedicated to wearing sunscreen. But coverage looks shiny or chalky, especially under makeup.
Many foundations and other makeup products offer a built-in sun protection factor (SPF). Is that your smartest beauty solution? Dermatologist Leslie Baumann, MD, says giving in to that temptation would be a mistake.
"Makeup does not provide enough coverage," she says. "You need seven times the normal amount of foundation and 14 times the normal amount of powder to get the sun protection factor on the label. No one does this."
So can you marry makeup and sunscreen in your routine and still look good? Yes, if you follow these steps.
1. Select the proper sunscreen.
Before you step in front of the bathroom mirror, find a sunscreen that offers enough protection. The Skin Cancer Foundation advises people to use a moisturizer containing broad-spectrum sunscreen (which means it blocks both UVA and UVB rays) with an SPF rating of at least 15. Ingredients such as zinc oxide, avobenzone (Parsol 1789) or ecamsule (Mexoryl), combined with octocrylene and avobenzone work best with makeup and provide broad spectrum sun protection.
Baumann says to layer a physical sunscreen, such as Aveeno Ultra-Calming Daily Moisturizer SPF 15, with a chemical sunscreen (either Topix Glycolix Elite Sunscreen SPF 30 or Blue Lizard Australian Sunscreen Sensitive Skin SPF 30), to block most of the sun’s rays.
Tina Turnbow, makeup artist, advises using a natural moisturizer,

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Retrieved Text: 10 Things You Didn’t Know About Sun Protection” article on WomansDay.com.
You can avoid burns by wearing a UV-monitoring wristband. According to David Bank, MD, president of the New York State Society of Dermatology and Dermatologic Surgery, it’s easy to assume that once you’ve put on sunscreen for the day, you don’t need to reapply. Instead of wondering if you’re getting too much sun or pressing your finger against your skin to gauge it (which doesn’t really work), consider using a smarter method promoted by dermatologists: UV-monitoring wristbands. “These tell you when you should reapply sunscreen based on how much sun exposure you are getting,” explains Dr. Bank. ”The wristbands provide you with a simple sun-sensitive gauge that alerts you through color change when you need to reapply sunscreen and when to get out of the sun and its potential damaging effects.” You can find these types of bands at your dermatologist’s office or purchase them online.
Gone are the days when a sunburn meant that your sunscreen had worn off. Ouch! Thanks to the clever folks at Skyrad we now have a solution: the Skyrad wristband (or bracelet as I’d like to call it)!
The Skyrad wristband acts as a sun-sensitive gauge: apply sunscreen to your body and to the wristband before sunbathing, going to the beach, playing by the pool or just enjoying the outdoors. Watch as the band changes colors so you know exactly when you need to reapply and avoid the risk of painful sun damage, keeping your skin healthy and radiant.
The band will work

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Retrieved Text: When you’re faced with lots of sunscreen options, it’s easy to be overwhelmed by all the different types and brands. But the first thing that really matters is the SPF.
Let’s talk about what is the minimum SPF you should be reaching for next time you buy sunscreen.
When looking at a sunscreen bottle, we know a high SPF is good, but maybe not why it’s good. By understanding what SPF measures, we can decide how much is right for us.
SPF is an acronym for Sun Protection Factor, a measurement of how long it takes someone to burn with and without the sunscreen. This is learned by applying the product on a participant and comparing the length of time it takes protected and unprotected skin to burn under a UV lamp.
An SPF of 10, for example, means that it took participants in that sunscreen’s tests 10 times longer to burn while wearing it and thus protects from 90% of sunburn-causing UVB rays.
Obviously, the higher the SPF, the longer you could theoretically go without burning and the more protection you are getting from damaging UV rays.
So what SPF is enough?
The FDA seems to think that SPF 15 is required according to its sunscreen regulations, but most dermatologists and skin cancer specialists conclude that SPF 30 is the minimum to truly protect against damage. Those with lighter skin tones are advised to wear higher SPF sunscreen and to wear it and reapply it more often.
Another thing to consider is whether or not the sunscreen is broad spectrum. This is where

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Retrieved Text: When it comes to the SPF number on our sunscreen bottles, most people shrug and grab the highest one, figuring bigger is better.
SPF 30? 50? 75? Bring it on—it will work, right?
There's actually much more to it than that, and it's all rather scientific. Simply put, SPF, or Sun Protection Factor, is a measure of how well a sunscreen will protect your skin from UVB rays.
Two kinds of UV radiation—UVA and UVB—can damage the skin. UVB rays are usually the culprit behind those pink, peeling sunburns, but UVA rays can be just as problematic. We have UVA rays to thank for wrinkles and leathery, saggy skin.
Wearing sunscreen with an SPF rating gives you a certain amount more time of safe sun exposure. It's fairly simple to calculate how long you can stay in the sun safely, as long as you know the SPF number and how long it takes you to develop a sunburn normally.
To calculate the safety of your sunscreen, multiply the number of minutes you can sit outside without burning by the SPF number. For example, if you would normally burn after 10 minutes in the sun, applying sunscreen with an SPF rating of 15 would allow you to stay in the sun safely for about 150 minutes. Of course, this is a rough estimate, and it really depends on your skin type, the amount of sunscreen you use, and the intensity of the sunlight you’re in.
Interestingly, the SPF scale is not linear. Contrary to what you might think, upgrading from SPF 15 to

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Retrieved Text: It’s scary to think, but researchers with the American Cancer Society say more people are diagnosed with skin cancer each year in the United States than all other cancers combined. What’s reassuring, though, is that there’s is more than one way to protect you and your kids from the sun’s damaging rays; and sunscreen tops the list. But not all sunscreens are created equal, so if you’re looking for the best sunscreen for kids (and for you, too), it can be challenging. But it doesn’t have to be.
A recent study found melanoma (the deadliest form of skin cancer) accounts for up to three percent of all pediatric cancers. And additional research points out that one in five people will develop skin cancer at some point during their lifetime. But a study in the Journal of Clinical Oncology found using sunscreen can reduce your chances of a melanoma diagnosis by as much as 73 pecent.
So, let’s take a look at the best sunscreen for kids (and you, too).
If you’re looking for the best sunscreen for kids, and the rest of your family, the first thing you’re probably going to look at is SPF. That’s because the most important job of your sunscreen is to prevent sunburn and SPF stands for “sun protection factor”. The SPF of your chosen sunscreen tells you how good of a job that particular product will do to protect your skin from UVB rays.
When making your decision, you should take into account the fairness of your skin and the amount of time you

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Retrieved Text: ​What types of sunscreen are available?
​What does broad spectrum mean?
Sunscreens either absorb or reflect UV radiation.
A sunscreen may contain one or both types since different UV filters are active against different UV wavelengths.
In Australia, sunscreens are classified as ‘primary’ – if their main function is for sun protection of the skin, or ‘secondary’/’cosmetic’ – if their main function is not as a sunscreen but they also provide sun protection.
​The sun produces two types of UV radiation that can damage the skin: UVA and UVB. Broad-spectrum sunscreens provide protection from both types of radiation. Products that are not broad spectrum protect mainly against UVB.
UVA is mainly responsible for unseen damage to the skin, resulting in premature ageing, while UVB is mainly responsible for visible damage to the skin, seen as reddening and sunburn. Both can cause skin cancer.
In Australia, broad spectrum is a compulsory requirement for all sunscreen products, except for colour cosmetic and lip products with SPF less than 30.
SPF provides a way of comparing the protection offered by different sunscreens. It indicates how much longer it will take your skin to start burning than if you were not wearing the sunscreen. This means that the SPF refers predominantly to its performance against UVB (“burning rays”).
This of course depends on you using the sunscreen correctly.
For example, if your skin normally starts to turn red after 10 minutes in the sun, an SPF 30 sunscreen will provide sun protection for roughly 30 times as long – 300 minutes.
In Australia, SPF claims are limited to 4, 6, 8,

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Retrieved Text: Broad spectrum UVA-UVB protection with a range of textures suitable for every sensitive skin in the family. The No.1 recommended brand by dermatologists.
Don’t face the day without our Anthelios sun protection creams and lotions. With more than 40 years of research, La Roche-Posay has developed a range of non-toxic sunscreen for sensitive skin that will allow you to enjoy your days in the sun worry free. While most sunscreens leave your face feeling weighed down, Anthelios’ sunscreen for face has a lightweight texture that is ideal for daily SPF protection. Anthelios is also a safe sunscreen option for anyone suffering from sensitive skin or atopic dermatitis. Protect your skin from everyday sun damage by including Anthelios’ sun blocking power in your beauty routine with our tinted sunscreen primer for sensitive skin. For combined hydration and UVA protection try our non-greasy Anthelios SX sunscreen lotion, perfect for sensitive and dehydrated skin. To address aging concerns and loss of skin density, discover La Roche-Posay’s anti-aging care line, Substiane.
Sunscreen re-application is as important as initial application. Sunscreen lotion should be applied 30 minutes prior to be exposed to the sun, and usually lasts for about 2 hours once on the skin. And so, it is important to reapply sun protection throughout the day to ensure its full effect. Carrying a non toxic sunscreen mist like the Anthelios Mist from La Roche-Posay is perfect in this regard as you can carry it with you throughout the day, touching up as needed. Sunscreen, once opened, generally can last up to 3

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Retrieved Text: Sunlight is strongest when it is directly above the sky. This is why health professionals advise that a person must avoid the sun between ten o’clock in the morning to four o’clock in the afternoon. A marathon conducted at exactly twelve noon not only plays havoc on the skin, but also causes heat stroke and dehydration.
If going out in the sun is unavoidable during such hours, a person should wear protective clothing. Protective clothing can reduce the skin’s exposure to sunlight. Long pants protect the legs. Long-sleeved shirts protect the arms. And broad-brimmed hats can protect the face, especially the eyes. Umbrellas are also effective tools in reducing sun exposure.
A sunburn is an actual burn of your skin from the ultraviolet (UV) light from the sun or other UV light sources (ie tanning beds). A sunburn can occur from as little as 15 minutes of midday sun exposure in a very light-skinned person.
The first signs of a sunburn may not appear for a few hours after the UV exposure. Sunburns may often appear “worse” the day after being at the beach, as it can take 24 hours or longer for the full effect of the UV damage to your skin to appear.
Sunburned skin is red and tender skin that is warm to the touch. Severe sunburned skin may result in the formation of blisters. Almost all sunburned skin will result in skin peeling on the burned areas several days after the sunburn.
Take anti-inflammatory medications such as ibuprophen (Advil, Motrin), naproxen (Aleve) or aspirin. Do NOT give

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Retrieved Text: If you�ve bought sunscreen lately, you may have noticed that 70 is the new 15.
We used to feel safe with sunscreen labeled SPF 15. We thought �sun protection factor� 15 meant we could stay in the sun 15 times longer than we could with no sunscreen at all.
SPF numbers have less to do with time in the sun and more to do with the amount of harmful ultraviolet light making its way to your skin, according to the Food and Drug Administration. And now that SPF numbers are breaking into the triple digits � a handful of products boast a sun protection factor of 100 � the lowly SPF 15 sounds like a sunburn waiting to happen.
A hat is a good idea, particularly for men with thinning hair, Hughes says. And people with short hair must remember to put lotion on the tops of their ears, a vulnerable spot for sunburns and skin cancer.
Many of Hughes� patients are young people who have been diagnosed with melanoma, a skin cancer usually caused by too much exposure to the sun. Hughes teaches families good skin-care habits and fields plenty of questions about SPF numbers along the way.
SPF numbers are often misinterpreted. If you feel like doing the math, Hughes says, think of the SPF number as X times more coverage than no sunscreen at all. To figure out the percentage of harmful rays that SPF 15 absorbs, he says, divide 14 by 15. For SPF 30, divide 29 by 30. And so on.
You�ll discover that SPF 15 blocks

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Retrieved Text: 1. The sun emits two types of rays that reach your skin, UVA and UVB. What’s the difference between the two?
Ultraviolet A (UVA) rays emit the same amount of radiation from sunrise to sunset, 365 days a year. Ultraviolet B (UVB) rays are stronger in the summer, especially between 10 a.m. and 4 p.m.
2. Are UVA and UVB rays equally harmful to skin?
Yes, but they affect it in different ways. UVB rays are responsible for sunburn and skin redness. (Think “B” for “burning.”) They cause inflammation, surface dryness and excess dry skin buildup.
UVA rays are weaker than UVB rays but pass further into your skin. They stimulate excess pigment, resulting in dark marks, age spots and dullness. UVAs also break down collagen and elastin, causing lines, wrinkles and sagging. UVA rays can penetrate glass, which means they harm your skin even while indoors.
3. What does SPF stand for, and how does it work?
SPF is short for “Sun Protection Factor.” The higher the SPF, the more protection. But exactly how long a sunscreen protects you depends on your skin color and its tolerance to UVB rays.
To get a sense of how long you can stay in the sun, multiply your sunscreen’s SPF number by the amount of time it takes your skin to burn in the sun.
…but there’s a little more to it than this. First, no sunscreen can block out 100% of the sun’s rays. Since you can’t rely on sunscreen for complete protection, be sure to cover up your body and wear a big hat

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Retrieved Text: Learning about sunscreen and applying it properly is one example of a small change that can positively affect your well-being. Spending time in your hot tub is another; it’s part of a holistic approach to wellness with significant benefits. Just 20 minutes a day in your own personal spa retreat can help you reduce stress, increase flexibility, help increase circulation, promote muscle recovery and improve sleep.
It’s summer—the time of year when we’re all exposed to more sunlight. We know by now that we should wear sunscreen when spending time in the sunny outdoors. But many of us don’t realize that sun protection is a year-round activity if we truly want to avoid potential skin damage.
When soaking in your hot tub consider a spa side umbrella to protect your skin.
Armed with a bit more knowledge and just a few minutes of effort each day, you can make positive changes that can protect your skin from unnecessary aging and reduce the risk of skin cancer.
How does sunlight causes skin damage?
1) UV-B is associated with sunburns.
2) UV–A is associated with skin aging.
Consider using your hot tub in the early mornings or evenings to avoid direct sun exposure.
Can you get skin cancer from one really bad sunburn?
Apparently this question gets asked a lot on the Internet. The answer depends on the frequency. If you have never been over-exposed to the sun and you get a bad sunburn then perhaps there is little damage done. The reality though is that you don’t need a sunburn to get skin cancer. According to

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Retrieved Text: (Reuters Health) - The number of women affected by the deadliest form of skin cancer could fall by almost a fifth if they all used sunscreen with a sun protection factor (SPF) of 15 or higher, a new study suggests.
While it may seem obvious that sunscreen with a higher SPF would protect against skin cancer, the study’s lead author said past research produced conflicting results, in part because many sunscreen users don’t apply sunscreens properly.
In addition, said Reza Ghiasvand of the University of Oslo in Norway, people often don’t reapply sunscreen as recommended. As a result, they end up with sunburns that increase their risk of melanoma, which is the deadliest form of skin cancer.
In 2016, more than 76,000 people in the United States will be diagnosed with melanoma, the National Cancer Institute estimates, and more than 10,000 will die of it.
The new findings are drawn from nearly 144,000 women who enrolled in the Norwegian Women and Cancer Study between 1991 and 2007, at ages 40 to 75. Over the next 11 years, 722 of them developed melanoma.
According to the results in the Journal of Clinical Oncology, sunscreen users were more likely to report sunburns, sunbathing vacations and indoor tanning. But those who had used sunscreen with an SPF of 15 or higher at least once in their lives were about 33 percent less likely to develop melanoma during the study than women who used only weaker sunscreens.
If every woman between the ages of 40 and 75 years used sunscreen with an SPF of at least

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Retrieved Text: NO-AD Suncare Sunscreen Lotion has a SPF rating 45 and is made with Aloe and Vitamin E.
Advertências: For external use only. Do not use on damaged or broken skin. When using this product keep out of eyes. Rinse with water to remove. Stop use and ask a doctor if rash occurs. Keep out of reach of children. If product is swallowed, get medical help or contact a Poison Control Center right away. For use on skin only. Avoid contact with fabric. Sun protection measures: Spending time in the sun increases your risk of skin cancer and early skin aging. To decrease this risk, regularly use a sunscreen with a Broad Spectrum SPF value of 15 or higher and other sun protection measures including: limit time in the sun, especially from 10 a.m. -2 p.m. and wear long-sleeved shirts, pants, hats and sunglasses. Children under 6 months: Ask a doctor. For use on skin only.
Recomendações de uso: Apply liberally 15 minutes before sun exposure. Reapply after 80 minutes of swimming or sweating, immediately after towel drying, or at least every 2 hours. Sun protection measures. Spending time in the sun increases your risk of skin cancer and early skin aging. To decrease this risk, regularly use a sunscreen with a broad spectrum SPF value of 15 or higher and other sun protection measures including: Limit time in the sun, especially from 10am - 2pm, wear long-sleeved shirts, pants, hats, and sunglasses. Children under 6 months: Ask a doctor. Protect this product from excessive heat and direct sun.

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Score: 76.09952
Retrieved Text: Despite the recent changes in labeling mandated by the U.S. Food and Drug Administration (FDA), a recent study suggests the terminology on sunscreen labels may still be confusing consumers.
“We need to do a better job of educating people about sun protection and make it easier for them to understand labels,” said Dr. Roopal Kundu, lead author of the Northwestern University study "Assessment of Consumer Knowledge of New Sunscreen Labels” which appeared online in JAMA Dermatology ahead of print.
In this particular study involving 114 participants, only 43% understood the definition of the sun protection factor (SPF) value. (Dermatologists Answer Burning Questions About Sunscreens - Click here to read more).
Fewer than half (37.7%) were able to correctly identify the terminology that indicated how well the sunscreen protected against skin cancer, photoaging (7.0%) and sunburns (22.8%).
Most participants correctly identified higher SPF values as correlated with increased protection against sunburns (92.1%) and skin cancer (71.9%) but only 28.9% understood that it does not directly confer protection against photoaging.
Only 55.3% of participants correctly identified the amount of sunscreen needed to cover the entire body in order to achieve the advertised level of sun protection.
“Interestingly, participants who indicated ‘highest SPF available’ as an important factor in their sunscreen purchasing decision were less likely to answer this question correctly compared with those who did not consider SPF value to be an important factor,” the study said.
75.4% identified prevention of sunburns as an important factor in their decision to wear sunscreen, followed by preventing skin cancer (65.8%).
The top three influences in the participants’ decisions

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Retrieved Text: SPF - do the numbers add up?
UV radiation is linked to more cancers worldwide than any other carcinogen. Skin cancer accounts for 80% of all new cancer diagnoses in Australia. I am often perplexed at the number of people I encounter who are worried about preservatives, chemicals in food, nanoparticles in sunscreen, and various other ‘nasties.’ None of these have any scientific backing to suggest they pose any risk to health, let alone cancer. We do know with great scientific vigour, that the greater risk is the harmful rays of our sun.
Sunburn causes 95% of melanoma according to cancer council Victoria. So it makes sense to protect yourself against something you know will do you damage.
Well avoiding the sun is one option. But What about Vitamin D? Well, the Cancer Council Victoria suggests that as we don't know the safe level of UV exposure to get Vitamin D conversion, then you are better off staying out of it. If you are low in Vitamin D, they suggest taking a supplement.
Always use a sunscreen with high SPF.
UVB is responsible for most of the skin damage. SPF – Sun protection factor - was a system devised to designate topical preparations and their ability to protect the skin from UV exposure.
So what’s in the number?
The SPF number is the length of time your skin can be exposed to UV before it becomes red. For example, an SPF of 15, means you can stay out 15 times longer in the sun before going red, then without sunscreen. An SPF of

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Retrieved Text: Fourth of July weekend is here! Many of us will certainly be poolside or vacationing at the beach. Just a reminder to wear a hat and apply sunscreen liberally while in the sun. Enjoy your holiday but protect your skin to keep it looking youthful and beautiful for many years to come. Speaking of sunscreen… You’ve probably heard about some new changes to sunscreen labeling.
Did you know that the current FDA sunscreen regulations were written in 1978 and not updated since then? If you aren’t old enough to remember 1978, or need a reminder, 1978 was the year that “Stayin Alive” by the Bee Gees was a number one song, and people laid out in the sun using baby oil and reflective mirrors! Most sun lotions were intended to encourage tanning, not protect against it. So, finally after 33 years the Food and Drug Administration has taken steps to help consumers sort through the sunscreen mess. New FDA sunscreen rules will take a lot of the guesswork out of reading, understanding, and actually believing sunscreen labels.
You probably have strolled through the sunscreen aisles and seen the claims, “100 SPF”, “Waterproof all day”, “Even Works on Wet Skin”, and wondered how is that even possible? The FDA is hoping that the new rules, which go into effect in 2012, can get rid products of these false claims and make choosing a sunscreen much easier. The rules will now ban sunscreen manufacturers from claiming their products are waterproof, sweat proof or even calling them “sunblock”, because these claims

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Retrieved Text: Sunscreen 101 — What Do SPF Numbers Mean?
In the past, you may have been told that SPF numbers were relatively simple to understand. If you can be out in the sun for 10 minutes with unprotected skin before your skin would begin to burn, the explanation went, then with an SPF 15, you could stay in the sun 15 times as long, or 150 minutes before you would burn. Simple, right? Not so fast, the science behind SPF is actually quite detailed, and sunscreens should be reapplied every 2 hours, regardless of the SPF.
1. Look for Broad Spectrum coverage. While we generally apply sunscreen in the summer to avoid a sunburn, UVA rays are present year-round, and those are the rays that have an aging effect on the skin. To keep your skin looking its best, as well as avoiding an increased risk of skin cancer, you want protection from UVA rays and UVB rays which is what Broad Spectrum protection offers.
2. Go for SPF 30 to 50. Even if you had SPF 100, it wouldn't protect you from 100% of the sun's rays, so looking for that sort of protection is not necessary. SPF 15 protects you from slightly more than 93% of the sun's UVB rays. SPF 30, even though it LOOKS like it offers double the protection of SPF 15, protects you from nearly 97% of the UVB rays. As the SPF goes up, the percentage of protection increases only slightly--when you jump up to SPF 50, the increase in protection is even

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Retrieved Text: Steps Every Man Needs to Follow When Applying Sunscreen.
Using sunscreen might not be as simple as you think: Most people hold inaccurate beliefs about their sunblock, new research from the American Academy of Dermatology (AAD) suggests.
And these misconceptions might leave you at greater risk of developing skin cancer.
In the survey, only 32 percent of respondents knew that an SPF 30 sunscreen does not provide twice as much protection as an SPF 15 sunscreen does.
In fact, the increase in protection from an SPF 15 to an SPF 30 isn’t very significant.
An SPF 30 blocks 97 percent of sunburn-causing UVB rays, while an SPF 15 blocks 93 percent, says Josh Zeichner, M.D., a spokesman for the AAD.
That means an SPF 30 blocks only 4 percent more UVB rays than SPF 15 does, a far cry from the “double” the numbers behind them would have you believe.
What’s more, just under half of those surveyed knew that a higher SPF sunscreen doesn’t protect you from the sun for a longer time than a lower SPF one does.
The real deal: Any sunscreen, no matter the SPF, wears off after two hours.
Putting too much faith in high SPF—whether it’s for amount of protection or how long you can safely stay in the sun—can be dangerous, since it can lead to a false sense of security regarding your burn risk, says Dr. Zeichner.
That may mean you might be more likely to stay in the sun for longer than you should or put off reapplying more sunscreen, which can make you more likely to

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Retrieved Text: The NIVEA Men Energy Broad Spectrum SPF 15 Sunscreen is a lotion that revitalizes and energizes the skin.
It can be used every day as a screen against the ravaging impact of the sun.
It’s a broad spectrum lotion that will protect the skin from both UVA and UVB rays. The biggest plus to this lotion is the energizing nature with the addition of Q10.
The company began making skin cream in 1911. It came in a small, metal tin even from the beginning. It started as an emulsifier lotion that combined oil and water into a mixture that would moisturize skin.
The creator of the cream was Dr. Isaac Lifschutz, but it was a dermatologist professor named Paul Gerson Unna who saw the possibilities.
He brought the new emulsifier to a chemist, and they started a company. They named the cream NIVEA based on the Latin word for snow.
CoEnzyme Q10 is an antioxidant that occurs naturally in the body. It protects cells from damage. Throughout your lifetime, the level of Q10 will rise and fall.
It rises towards its peak at ages 20 to 30, but then it will decline as you age beyond 30. In the skin, Q10 prevents damage and helps produce collagen.
Collagen is what gives skin its elasticity in your youth. Elasticity is the firmness that will fade as you age.
CoEnzyme Q10 stimulates the production of collagen, which leads to less wrinkles and helps avoid skin that looks like leather.
When you need to replace Q10, it makes sense to use a lotion that has the ability to stimulate

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Retrieved Text: Credits: "Artem Bali at Unsplash.com"
The sun is a necessary part of life, but too much sun exposure can be very harmful. Sun exposure can lead to skin damage, premature skin aging, and possibly over time, result in skin cancer. Over one million people in America are diagnosed with skin cancer each year from overexposure to the sun. Skin cancer is becoming one of the most common cancers in the United States, with an estimated 1 in 5 people who will get it during their lifetime. Sunscreen protection and refraining from sun exposure, in general, are more important than ever. Choosing the right sunscreen can often be confusing due to the sheer number of options that are out on the market.
What is SPF, and does it matter?
The simple answer is yes, SPF does matter. Sun Protection Factor, also known as SPF, is a measure of how well a sunscreen can protect human skin from the sun’s harmful UVB rays. More specifically, SPF refers to how well a sunscreen protects the skin from turning red and causing the colloquial “sunburn”.
Unfortunately, SPF cannot filter 100 percent of the rays but can get quite close. The strength of SPF you choose determines how well the skin will be protected. For example, SPF 15 filters 93 percent of UVB rays, SPF 30 filters out 97 percent, and SPF 50 filters 98 percent of rays. At some point, there is no real benefit to getting a higher SPF. It is recommended by the American Academy of Dermatology to utilize a sunscreen with

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Retrieved Text: Dear Science: What does sunscreen SPF mean, and what happens if you mix them?
Dear Science: I'm gearing up for a summer vacation, and I've been burned before — so I want to make the most of all these half bottles of sunscreen left in my cabinet. If you mix equal amounts of SPF 10 sunscreen and SPF 30 sunscreen, do you get SPF 10, 20, 30 or 40? And what SPF should I be aiming for?
Step away from the mixing bowl, friend. Mixing sunscreens is a no-no. But it's important to understand why. First, let's get one thing out of the way: What the heck even is SPF?
According to Shari Lipner, dermatologist at Weill Cornell Medicine and NewYork-Presbyterian, your sunscreen's SPF (sun protection factor) does indeed tell you how much sun protection it can offer you. Researchers test sunscreen on bits of skin, comparing it with totally unprotected skin as they're both exposed to sunlight. SPF is a measurement of how much ultraviolet radiation — short, invisible wavelengths of light from the sun — is necessary to burn the sunscreened skin as compared with the unadorned flesh.
The numbers themselves refer to how long you can bake in the sun without burning: If it takes 20 minutes for your bare skin to start reddening, using an SPF 15 sunscreen is meant to let you have fun in the sun for 15 times longer – about five hours. But you still need to reapply it every two hours because of sweating and all that, so don't actually pay

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Retrieved Text: Z Blok was the only sunscreen I used for our recent 22 day hike and climb of Mera Peak in the Nepalese Himalaya. The non greasy formula was perfect for use on an expedition where the first shower was on day 18! I'll never sail or climb without Z Blok in future.
Q: When should sunscreen be used?
Sunscreens should be used every day if you plan on being outside. Even sitting by a window at home or in a car exposes your skin to the sun’s UVA rays, which penetrate glass. On a cloudy day, up to 80 percent of the sun's ultraviolet rays will pass through clouds.
Q: How often should sunscreen be applied?
Most sunscreens should be applied to your skin 15 or more minutes before going outdoors. But sunscreens with zinc or titanium oxide work right away because their efficacy is not dependent on being absorbed into the skin.
When applying sunscreen, pay particular attention to the face, ears, hands and arms, which typically get the most sun exposure. Also apply a lip balm that contains sunscreen with an SPF of 30. All sunscreens should be applied at least every 2 hours if swimming or perspiring heavily. Even sunscreens that claim to be water resistant lose their effectiveness with time and water exposure - you must re-apply to protect your skin.
Q. What is the difference between UVA and UVB rays?
UVB rays are the cause of sunburn on the surface of the skin. SPF only measures protection against UVB rays.
UVA rays cause DNA damage to the cells deeper

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Retrieved Text: What is the best sunscreen for children?
Picture it - a parent is standing in the sunscreen aisle at the local drug store, staring glossy-eyed at the shelves, determined to pick the best sunscreen for their kids. More often than not, they are dazed and confused by the countless bottles of lotions, gels, and sprays arranged so nicely on the selves right in front of their eyes.
Most parents usually decide on a sunscreen made specifically for children and with the highest SPF they can find. However, there are more important things to consider in sunscreens than just SPF 50+.
We hope to answer some of those bewildering questions here so you can make the best choice about sunscreen for your children.
However, choosing the right sunscreen is only half the battle, getting them to wear it is another issue altogether. Here are some tips to get your kids to apply sunscreen.
Sunscreens use chemicals to absorb UV rays.
Sunblocks physically deflect UV rays away from the skin.
Broad Spectrum Protection: New formulations in the sunscreen market have created “Broad Spectrum” protection. This provides protection against UVA (aging) and UVB (burning) rays with a combination of both chemical absorbers and physical blockers.
TIP: Parents should always look for products labeled Broad Spectrum to protect against both UVA and UVB rays.
SPF - What do the numbers really mean?
SPF-(Sun Protection Factor) measures the length of time a sunscreen will protect your skin from reddening or burning from UVB rays, compared to how long your skin would take to redden/ burn without sunscreen protection.
Don’t be swayed by

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Retrieved Text: Summer is here and it is already HOT outside. As we gear up to go to the pool to cool off we have to make sure and protect our skin from sun damage.
We all know we should avoid tanning beds and apply sunscreen to avoid getting a dreaded skin cancer in our future. The confusing issue comes when you make your Target run and see hundreds of sunscreen options and have no clue which one is actually worth your money.
So what sunscreen should you wear? How often should you reapply it? Is SPF 100 really better than SPF 30?
If your skin is a fair complection or have a family history of skin cancer you should consider wearing an SPF50 sunscreen to sun exposed areas. Otherwise most people can get away with wearing SPF30 when sun exposed. There is no data proving that any sunscreen greater than SPF 50 really works all that much better. So it may not be worth your extra money on the higher SPF when shopping.
If you take the SPF and multiply it by 10 you can get an idea of how long it will protect your skin from a sunburn without sweat or water involved.
Reapply sunscreen immediately if you get your skin wet from sweat or swimming. If you know you will be sweating or swimming then use a water resistant sunscreen.
Everyone should wear a daily facial sunscreen(EVEN IN THE WINTER AND ON A CLOUDY DAY) The face takes UV rays on daily whether we are by the pool or walking across

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Retrieved Text: Summiters Adventures - Sunscreen and how to wear it..
Normally in things to carry items for a any trek or expedition will have a sunscreen. But not many know what is a sunscreen and how to use it. Mr. Vishwanath with his experience in high altitude discloses the necessity to carry it and using it.
First of all. It is not a cream that can be applied easily anytime and start. No..!
Yes.Sure that will protect you from the sun exposure...for a little while. But to properly and effectively wear sunscreen and get its maximum benefits, you should follow these sunscreen tips.
There is no better way to prevent sunburn at high altitude than to cover up exposed parts with clothing. There is no suggestion from clinical experience that malignant melanomas are seen commonly in high altitude climbers than in the general population. Obviously, the more benign skin cancers are seen in more commonly in those who spend much time outdoors, and are probably more common in (for example) mountain guides than their office-based peers. Despite the recent publicity on sunscreens and melanomas, there is presently no definite evidence to suggest avoiding the use of sunscreens; there may however be further data about this.
Sunlight is composed of various wavelengths ranging from ultraviolet light through infrared to visible light - ultraviolet light is the most harmful to the skin and causes sunburn, ageing of the skin and, over the long term, skin cancer. Ultraviolet light is made up of UVC, UVB and UVA, UVC being the shorter wavelength that is filtered

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Input Text: Read the passage below and choose the right answer to the following question (choices are more or less ):

A sunscreen with a higher SPF value protects the skin longer.


A sunscreen with an SPF value of 30 will protect skin more or less than a sunscreen with an SPF value of 15?

Target Text: more

#### Retrieved Documents ####

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Retrieved Text: to keep your skin safe is by wearing sunscreen.
It is now easier to protect your skin than ever before. All sunscreen lotion labels will soon get a face lift to make it easier for you to pick the right sunscreen. Next time you shop for a sunscreen, look for the new “broad spectrum” label on the package.
Broad spectrum means that a product can block UVA and UVB sun rays equally. UVA and UVB rays can cause skin cancer, early skin aging and sunburn. In the past, sunscreens mostly protected your skin from UVB rays that cause sunburns.
How Else are Labels Changing?
What Product is the Best for Me?
Everyone’s skin can benefit from sunscreen. Sunscreen that does not have a broad spectrum label will NOT protect you from skin cancer and early skin aging. These changes are only for sunscreen lotion and not spray because you put on spray sunscreens differently than lotions. For the best protection, follow these guidelines.
Use at least an SPF 15 up to an SPF 50. SPF stands for Sun Protection Factor or how much sun protection a product offers. The higher the SPF value of the sunscreen, the better protection it will offer. But this is only up to SPF 50. Sunscreens with an SPF greater than 50 still work, but it is unclear if they work any better than SPF 50 lotions.
Use broad spectrum sunscreen with an SPF of 15 or higher. Broad spectrum SPF 15 products can protect your skin against sunburn, skin cancer and early sun aging.
If swimming or sweating,

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Retrieved Text: What SPF sunblock should you buy, SPF 15, 30, 60 or greater?
Use of Sunblock creams or sunscreens is now popular amongst both male and female sexes. When you go to a dermatologist or cosmetician to have an opinion about better skin care management, they will tell you to use a sunblock whenever you go out in the sun. When you go to a shop to buy a sunscreen, you don’t know what SPF sunblock should you buy?. You fear that an SPF 15 sunblock is nothing in front of SPF 50 or 90 sunblock, then you also worry about the cost of a high SPF sunblock.
Sun rays contain ultraviolet radiations that have the tendency to damage your skin. Our skin has the ability to resist this damage for a few minutes to an hour depending upon the colour of the skin. Dark coloured individuals tend to withstand the sunlight for a longer period of time as compared to a fair coloured individual. White skinned individuals more commonly complain of sun damage, rash, pimples and acne as compared to dark skinned individuals.
Why do the dark colored individuals withstand sunlight better?
Cosmetologist encourages the use of sunblock in adults when they go out in the sun. When you buy a sunscreen or sunblock cream, you see a special value on the pack represented by SPF. You may see various values of SPF, maybe 15, 24, 30, 40, 45, 60 etc. SPF stands for sun protection factor. The higher the value better will be the protection. For instance, a 15

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Retrieved Text: You can reduce the risk of getting skin cancer by protecting yourself and your children when you are in the sun. This means more than just wearing sunscreen on hot summer days. Up to 80% of the sun’s rays can reach you through light clouds, mist, and fog. You need to protect yourself even on cloudy days. Fresh snow reflects up to 95% of the sun’s rays, so remember to wear sunscreen in the snow. You can also get sunburned when you are in or on the water, so take precautions when you are swimming or boating.
Limit the amount of time you spend in the sun between the hours of 10 AM and 4 PM. This is when the sun’s rays are the strongest. Check the local UV index to see what kinds of sun protection you might need.
If you have to be in the sun, wear long pants and a long-sleeved shirt. Tightly woven, dark-colored fabrics give you more protection than light-colored, loosely woven clothes.
Use a broad-spectrum sunscreen every day that provides protection against both UV-A and UV-B ray with an SPF rating of 30 or higher. Apply liberally. As a general guideline, the portion you apply should roughly fill the cup of the palm of your hand.
Apply sunscreen at least 1/2 hour before you go into the sun. This allows the sunscreen to seep into the upper skin layers, giving you better protection.
Protect your lips with a lip balm that has an SPF of 15 or higher.
Reapply sunscreen (even waterproof sunscreen) every 2 hours,

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Retrieved Text: What SPF sunscreen should I use?
Nicole needs to know…Is there a really big difference between using SPF 15 and SPF 30 facial moisturizer? If so, why? I was told to wear 30 in order to prevent rosacea flare ups.
Skin exposure to UV rays is almost never good for the skin. It causes sun burn, wrinkles, dryness, and as you’ve implied, rosacea flare ups. This is why the most important thing you can do for your skin is to wear a sunscreen or stay out of the sun. But what kind of sunscreen should you use?
Before answering this, we should first tell you what the SPF number means. SPF stands for sun protection factor and it essentially is a rating of how much UV light will be blocked. In general, a higher SPF number offers more protection from UV exposure than a lower number. How effective it is depends on many factors but the number one factor is your skin type. SPF 15 means that if you would normally burn after being in the sun for 20 minutes, you will be able to stay in the sun for 15 times as long or 5 hours. But it is important to note that the SPF scale is not a linear one. An SPF 2 will block 50% of the UV light while an SPF 15 will block 92% of all the UV light that reaches your skin and an SPF 34 blocks 97% of the UV light.
Although skin type is the number one factor is determining the effectiveness

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Retrieved Text: 10 Things You Didn’t Know About Sun Protection” article on WomansDay.com.
You can avoid burns by wearing a UV-monitoring wristband. According to David Bank, MD, president of the New York State Society of Dermatology and Dermatologic Surgery, it’s easy to assume that once you’ve put on sunscreen for the day, you don’t need to reapply. Instead of wondering if you’re getting too much sun or pressing your finger against your skin to gauge it (which doesn’t really work), consider using a smarter method promoted by dermatologists: UV-monitoring wristbands. “These tell you when you should reapply sunscreen based on how much sun exposure you are getting,” explains Dr. Bank. ”The wristbands provide you with a simple sun-sensitive gauge that alerts you through color change when you need to reapply sunscreen and when to get out of the sun and its potential damaging effects.” You can find these types of bands at your dermatologist’s office or purchase them online.
Gone are the days when a sunburn meant that your sunscreen had worn off. Ouch! Thanks to the clever folks at Skyrad we now have a solution: the Skyrad wristband (or bracelet as I’d like to call it)!
The Skyrad wristband acts as a sun-sensitive gauge: apply sunscreen to your body and to the wristband before sunbathing, going to the beach, playing by the pool or just enjoying the outdoors. Watch as the band changes colors so you know exactly when you need to reapply and avoid the risk of painful sun damage, keeping your skin healthy and radiant.
The band will work

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Retrieved Text: Is Makeup With Sunscreen Enough to Protect Your Skin?
Many foundations and powders contain sunscreen, but is it enough for daily protection?
You want to prevent wrinkles and skin cancer, so you are dedicated to wearing sunscreen. But coverage looks shiny or chalky, especially under makeup.
Many foundations and other makeup products offer a built-in sun protection factor (SPF). Is that your smartest beauty solution? Dermatologist Leslie Baumann, MD, says giving in to that temptation would be a mistake.
"Makeup does not provide enough coverage," she says. "You need seven times the normal amount of foundation and 14 times the normal amount of powder to get the sun protection factor on the label. No one does this."
So can you marry makeup and sunscreen in your routine and still look good? Yes, if you follow these steps.
1. Select the proper sunscreen.
Before you step in front of the bathroom mirror, find a sunscreen that offers enough protection. The Skin Cancer Foundation advises people to use a moisturizer containing broad-spectrum sunscreen (which means it blocks both UVA and UVB rays) with an SPF rating of at least 15. Ingredients such as zinc oxide, avobenzone (Parsol 1789) or ecamsule (Mexoryl), combined with octocrylene and avobenzone work best with makeup and provide broad spectrum sun protection.
Baumann says to layer a physical sunscreen, such as Aveeno Ultra-Calming Daily Moisturizer SPF 15, with a chemical sunscreen (either Topix Glycolix Elite Sunscreen SPF 30 or Blue Lizard Australian Sunscreen Sensitive Skin SPF 30), to block most of the sun’s rays.
Tina Turnbow, makeup artist, advises using a natural moisturizer,

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Retrieved Text: When you’re faced with lots of sunscreen options, it’s easy to be overwhelmed by all the different types and brands. But the first thing that really matters is the SPF.
Let’s talk about what is the minimum SPF you should be reaching for next time you buy sunscreen.
When looking at a sunscreen bottle, we know a high SPF is good, but maybe not why it’s good. By understanding what SPF measures, we can decide how much is right for us.
SPF is an acronym for Sun Protection Factor, a measurement of how long it takes someone to burn with and without the sunscreen. This is learned by applying the product on a participant and comparing the length of time it takes protected and unprotected skin to burn under a UV lamp.
An SPF of 10, for example, means that it took participants in that sunscreen’s tests 10 times longer to burn while wearing it and thus protects from 90% of sunburn-causing UVB rays.
Obviously, the higher the SPF, the longer you could theoretically go without burning and the more protection you are getting from damaging UV rays.
So what SPF is enough?
The FDA seems to think that SPF 15 is required according to its sunscreen regulations, but most dermatologists and skin cancer specialists conclude that SPF 30 is the minimum to truly protect against damage. Those with lighter skin tones are advised to wear higher SPF sunscreen and to wear it and reapply it more often.
Another thing to consider is whether or not the sunscreen is broad spectrum. This is where

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Retrieved Text: ​What types of sunscreen are available?
​What does broad spectrum mean?
Sunscreens either absorb or reflect UV radiation.
A sunscreen may contain one or both types since different UV filters are active against different UV wavelengths.
In Australia, sunscreens are classified as ‘primary’ – if their main function is for sun protection of the skin, or ‘secondary’/’cosmetic’ – if their main function is not as a sunscreen but they also provide sun protection.
​The sun produces two types of UV radiation that can damage the skin: UVA and UVB. Broad-spectrum sunscreens provide protection from both types of radiation. Products that are not broad spectrum protect mainly against UVB.
UVA is mainly responsible for unseen damage to the skin, resulting in premature ageing, while UVB is mainly responsible for visible damage to the skin, seen as reddening and sunburn. Both can cause skin cancer.
In Australia, broad spectrum is a compulsory requirement for all sunscreen products, except for colour cosmetic and lip products with SPF less than 30.
SPF provides a way of comparing the protection offered by different sunscreens. It indicates how much longer it will take your skin to start burning than if you were not wearing the sunscreen. This means that the SPF refers predominantly to its performance against UVB (“burning rays”).
This of course depends on you using the sunscreen correctly.
For example, if your skin normally starts to turn red after 10 minutes in the sun, an SPF 30 sunscreen will provide sun protection for roughly 30 times as long – 300 minutes.
In Australia, SPF claims are limited to 4, 6, 8,

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Score: 78.78615
Retrieved Text: Get ready Portland: summer is officially here. And just in time for summer, the Food and Drug Administration has unveiled new FDA sunscreen regulations. The new regulations will change how sunscreens are labeled, starting in summer of 2012.
According to Jill Lindstrom M.D., a dermatologist for the FDA, “We encourage consumers to use sunscreens that are labeled with a broad spectrum SPF value of at least 15.
Broad spectrum sunscreens protect from UVA rays (which cause skin aging) and UVB rays (which cause sunburns).
What Are The New FDA Sunscreen Regulations?
Starting in 2012, sunscreens cannot be labeled with an SPF value higher than SPF 50. Also, manufacturers will have to prove their broad spectrum protection claims.
The new sunscreen label rules will also change the labels of sunscreens that are sweat resistant or water resistant. Currently, the labels may say “waterproof” or “sweatproof.” According to the FDA, sunscreens lose effectiveness when wet and will need to be reapplied frequently.
The FDA also states that they have no reason to believe that currently available sunscreens are unsafe. Remember, protecting your skin from the sun now can help protect your skin from early skin aging. Photoaging is skin aging caused by the sun. It is a major cause of fine lines and wrinkles, as well as changes in skin tone and texture.
If you feel your skin is already showing the effects of photoaging, make an appointment to learn how the skin and surgical treatments we offer can improve the appearance of skin aging. It is important that you protect your skin from the

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Rank: 9
Score: 78.23006
Retrieved Text: Learning about sunscreen and applying it properly is one example of a small change that can positively affect your well-being. Spending time in your hot tub is another; it’s part of a holistic approach to wellness with significant benefits. Just 20 minutes a day in your own personal spa retreat can help you reduce stress, increase flexibility, help increase circulation, promote muscle recovery and improve sleep.
It’s summer—the time of year when we’re all exposed to more sunlight. We know by now that we should wear sunscreen when spending time in the sunny outdoors. But many of us don’t realize that sun protection is a year-round activity if we truly want to avoid potential skin damage.
When soaking in your hot tub consider a spa side umbrella to protect your skin.
Armed with a bit more knowledge and just a few minutes of effort each day, you can make positive changes that can protect your skin from unnecessary aging and reduce the risk of skin cancer.
How does sunlight causes skin damage?
1) UV-B is associated with sunburns.
2) UV–A is associated with skin aging.
Consider using your hot tub in the early mornings or evenings to avoid direct sun exposure.
Can you get skin cancer from one really bad sunburn?
Apparently this question gets asked a lot on the Internet. The answer depends on the frequency. If you have never been over-exposed to the sun and you get a bad sunburn then perhaps there is little damage done. The reality though is that you don’t need a sunburn to get skin cancer. According to

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Rank: 10
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Retrieved Text: Summer is just around the corner, we are now pulling out shorts and dresses from our closet. It's a fantastic time to give our white, pale winter skin a glow with a spray tan. You book your spray tan with a Beauty Door Pro professional and now you think about how to maintain and protect your tan while being exposed to the sun.
I always get the call after about "What Sunscreen should I buy"???
Choose an oil free sunscreen lotion (that way it won't strip down your spray tan).
Use a sunscreen with the FDA recommend of no lower than SPF 30 and not higher than 50.
Sounds pretty easy to choose a sunscreen, until you get to the store or (Amazon) and see all 10 million sunscreen bottles and think how can I choose just one tube in an isle of brown and orange SPF containers.
A spray tan does NOT provide you with ANY sun protection so please please wear your sunscreen!
Let me explain how sunscreen works.
The SPF rating of any given sunscreen tells you what fraction of the sun’s rays will reach your skin.
Beauty Door Pro recommends that you always use a sunscreen with an SPF rating no lower than 30 and no higher than 50. Our recommendation is in line with that of the FDA. That may sound high when you want to get a tan, but remember that you’ll be doing it gradually to protect your skin as you will already have a tan (spray tan that is).
When sunscreen is properly applied, this chart explains

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Rank: 11
Score: 78.01909
Retrieved Text: Summer is here and it is already HOT outside. As we gear up to go to the pool to cool off we have to make sure and protect our skin from sun damage.
We all know we should avoid tanning beds and apply sunscreen to avoid getting a dreaded skin cancer in our future. The confusing issue comes when you make your Target run and see hundreds of sunscreen options and have no clue which one is actually worth your money.
So what sunscreen should you wear? How often should you reapply it? Is SPF 100 really better than SPF 30?
If your skin is a fair complection or have a family history of skin cancer you should consider wearing an SPF50 sunscreen to sun exposed areas. Otherwise most people can get away with wearing SPF30 when sun exposed. There is no data proving that any sunscreen greater than SPF 50 really works all that much better. So it may not be worth your extra money on the higher SPF when shopping.
If you take the SPF and multiply it by 10 you can get an idea of how long it will protect your skin from a sunburn without sweat or water involved.
Reapply sunscreen immediately if you get your skin wet from sweat or swimming. If you know you will be sweating or swimming then use a water resistant sunscreen.
Everyone should wear a daily facial sunscreen(EVEN IN THE WINTER AND ON A CLOUDY DAY) The face takes UV rays on daily whether we are by the pool or walking across

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Rank: 12
Score: 77.825096
Retrieved Text: When it comes to the SPF number on our sunscreen bottles, most people shrug and grab the highest one, figuring bigger is better.
SPF 30? 50? 75? Bring it on—it will work, right?
There's actually much more to it than that, and it's all rather scientific. Simply put, SPF, or Sun Protection Factor, is a measure of how well a sunscreen will protect your skin from UVB rays.
Two kinds of UV radiation—UVA and UVB—can damage the skin. UVB rays are usually the culprit behind those pink, peeling sunburns, but UVA rays can be just as problematic. We have UVA rays to thank for wrinkles and leathery, saggy skin.
Wearing sunscreen with an SPF rating gives you a certain amount more time of safe sun exposure. It's fairly simple to calculate how long you can stay in the sun safely, as long as you know the SPF number and how long it takes you to develop a sunburn normally.
To calculate the safety of your sunscreen, multiply the number of minutes you can sit outside without burning by the SPF number. For example, if you would normally burn after 10 minutes in the sun, applying sunscreen with an SPF rating of 15 would allow you to stay in the sun safely for about 150 minutes. Of course, this is a rough estimate, and it really depends on your skin type, the amount of sunscreen you use, and the intensity of the sunlight you’re in.
Interestingly, the SPF scale is not linear. Contrary to what you might think, upgrading from SPF 15 to

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Rank: 13
Score: 77.77616
Retrieved Text: Not all bottles are created equal. Check out how to really protect your skin this summer.
Sunscreen, like watermelon and Fourth of July fireworks, is a summertime essential. This sunburn- and cancer-fighting product comes in more tubes, sprays, and sticks and with more SPFs, bells, and whistles than any consumer knows what to do with. Finding an effective sunscreen that’s cruelty free? That might leave you in the drugstore aisle for hours. We help you spend less time buying bottles and more time enjoying the sun safely by explaining what’s on those labels and which ones are animal-friendly.
More than 2 million people in the US are treated for skin cancer each year. Those of us (read: all of us) who don’t want to be one of the millions need to know exactly what is going on with sunscreen. Most of us choose a tube based on its sun protection factor, or SPF, which supposedly indicates how many minutes the sunscreen will protect you from UVB rays only. UVA rays, not so much. The Food and Drug Administration (FDA), for the first time in more than three decades, released new guidelines on sunscreens in an effort to prevent companies from making dubious claims about their products. The new rules include a requirement that sunscreens equally protect against UVA rays (long-wave rays that can cause skin aging and might initiate the development of skin cancer), and UVB rays (short-wave rays that are the main culprit of sunburn and is the major initiator of skin cancer) in order to be

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Rank: 14
Score: 77.59082
Retrieved Text: Broad spectrum UVA-UVB protection with a range of textures suitable for every sensitive skin in the family. The No.1 recommended brand by dermatologists.
Don’t face the day without our Anthelios sun protection creams and lotions. With more than 40 years of research, La Roche-Posay has developed a range of non-toxic sunscreen for sensitive skin that will allow you to enjoy your days in the sun worry free. While most sunscreens leave your face feeling weighed down, Anthelios’ sunscreen for face has a lightweight texture that is ideal for daily SPF protection. Anthelios is also a safe sunscreen option for anyone suffering from sensitive skin or atopic dermatitis. Protect your skin from everyday sun damage by including Anthelios’ sun blocking power in your beauty routine with our tinted sunscreen primer for sensitive skin. For combined hydration and UVA protection try our non-greasy Anthelios SX sunscreen lotion, perfect for sensitive and dehydrated skin. To address aging concerns and loss of skin density, discover La Roche-Posay’s anti-aging care line, Substiane.
Sunscreen re-application is as important as initial application. Sunscreen lotion should be applied 30 minutes prior to be exposed to the sun, and usually lasts for about 2 hours once on the skin. And so, it is important to reapply sun protection throughout the day to ensure its full effect. Carrying a non toxic sunscreen mist like the Anthelios Mist from La Roche-Posay is perfect in this regard as you can carry it with you throughout the day, touching up as needed. Sunscreen, once opened, generally can last up to 3

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Rank: 15
Score: 77.5908
Retrieved Text: Want to know how to find our best sunscreen for your skin type? We created a step-by-step guide to help you find a sun protection product that can work for you—and your skin—ahead.
Sunscreen is—in a way—like life insurance for your skin. When used properly—i.e. applied daily and reapplied at least every two hours—it can help protect the surface skin from sun damage. That being said, many of us are (unknowingly) guilty of choosing a sunscreen that is not formulated for our specific skin type. This is a commonly-missed opportunity to help care for your skin while also helping to protect it. Hear us out! Not all sunscreens are created equal. In fact, there are sunscreens formulated for specific skin types—so, if you’re applying a sunscreen that was made for a different skin type than that of your own, you may be experiencing some skin care woes. Worry not, we share a guide to finding the best sunscreens for your skin type, ahead.
The first step in finding a sunscreen designed for your skin type is determining what your skin type actually is. Do you experience dry skin on your cheeks, but oily skin on your T-Zone? This could be a sign of combination skin. Is your complexion oil-ridden and acne-prone? Sounds like your skin type may be oily. If you need help determining your skin type, we recommend scheduling an appointment with your dermatologist.
Already know your skin type? Skip ahead to step two!
Once you’ve determined whether you experience dry skin, oily skin, combination skin, acne-prone skin, and

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Score: 77.40179
Retrieved Text: It’s scary to think, but researchers with the American Cancer Society say more people are diagnosed with skin cancer each year in the United States than all other cancers combined. What’s reassuring, though, is that there’s is more than one way to protect you and your kids from the sun’s damaging rays; and sunscreen tops the list. But not all sunscreens are created equal, so if you’re looking for the best sunscreen for kids (and for you, too), it can be challenging. But it doesn’t have to be.
A recent study found melanoma (the deadliest form of skin cancer) accounts for up to three percent of all pediatric cancers. And additional research points out that one in five people will develop skin cancer at some point during their lifetime. But a study in the Journal of Clinical Oncology found using sunscreen can reduce your chances of a melanoma diagnosis by as much as 73 pecent.
So, let’s take a look at the best sunscreen for kids (and you, too).
If you’re looking for the best sunscreen for kids, and the rest of your family, the first thing you’re probably going to look at is SPF. That’s because the most important job of your sunscreen is to prevent sunburn and SPF stands for “sun protection factor”. The SPF of your chosen sunscreen tells you how good of a job that particular product will do to protect your skin from UVB rays.
When making your decision, you should take into account the fairness of your skin and the amount of time you

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Retrieved Text: What is the best sunscreen for children?
Picture it - a parent is standing in the sunscreen aisle at the local drug store, staring glossy-eyed at the shelves, determined to pick the best sunscreen for their kids. More often than not, they are dazed and confused by the countless bottles of lotions, gels, and sprays arranged so nicely on the selves right in front of their eyes.
Most parents usually decide on a sunscreen made specifically for children and with the highest SPF they can find. However, there are more important things to consider in sunscreens than just SPF 50+.
We hope to answer some of those bewildering questions here so you can make the best choice about sunscreen for your children.
However, choosing the right sunscreen is only half the battle, getting them to wear it is another issue altogether. Here are some tips to get your kids to apply sunscreen.
Sunscreens use chemicals to absorb UV rays.
Sunblocks physically deflect UV rays away from the skin.
Broad Spectrum Protection: New formulations in the sunscreen market have created “Broad Spectrum” protection. This provides protection against UVA (aging) and UVB (burning) rays with a combination of both chemical absorbers and physical blockers.
TIP: Parents should always look for products labeled Broad Spectrum to protect against both UVA and UVB rays.
SPF - What do the numbers really mean?
SPF-(Sun Protection Factor) measures the length of time a sunscreen will protect your skin from reddening or burning from UVB rays, compared to how long your skin would take to redden/ burn without sunscreen protection.
Don’t be swayed by

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Retrieved Text: 1. The sun emits two types of rays that reach your skin, UVA and UVB. What’s the difference between the two?
Ultraviolet A (UVA) rays emit the same amount of radiation from sunrise to sunset, 365 days a year. Ultraviolet B (UVB) rays are stronger in the summer, especially between 10 a.m. and 4 p.m.
2. Are UVA and UVB rays equally harmful to skin?
Yes, but they affect it in different ways. UVB rays are responsible for sunburn and skin redness. (Think “B” for “burning.”) They cause inflammation, surface dryness and excess dry skin buildup.
UVA rays are weaker than UVB rays but pass further into your skin. They stimulate excess pigment, resulting in dark marks, age spots and dullness. UVAs also break down collagen and elastin, causing lines, wrinkles and sagging. UVA rays can penetrate glass, which means they harm your skin even while indoors.
3. What does SPF stand for, and how does it work?
SPF is short for “Sun Protection Factor.” The higher the SPF, the more protection. But exactly how long a sunscreen protects you depends on your skin color and its tolerance to UVB rays.
To get a sense of how long you can stay in the sun, multiply your sunscreen’s SPF number by the amount of time it takes your skin to burn in the sun.
…but there’s a little more to it than this. First, no sunscreen can block out 100% of the sun’s rays. Since you can’t rely on sunscreen for complete protection, be sure to cover up your body and wear a big hat

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Retrieved Text: Rain or shine, sun protection is an absolutely essential step in your beauty routine. Research has shown that exposure to UV radiation accelerates skin aging and increases the risk of developing skin cancers such as melanoma. As carefree sun lovers age, their skin develops leather-like texture riddled with sunspots and wrinkles. Those who are smart when it comes to sun exposure will enjoy smooth, beautiful skin for longer.
In the summer months, you should be especially careful about protecting your face and wear sunglasses and a broad brimmed hat if you are venturing outdoors. Additionally, you should protect any area of the skin that will be exposed to the sun by applying sunscreen. The efficacy of sunscreen products is measured by the SPF rating system. We recommend regularly using sunscreens that fall in the high protection category. These products range in value from SPF 30 to SPF 50.
Sunscreens are regulated in the US and Canada as an over the counter medication, while they are treated as a cosmetic product in Europe and Japan. Due to regulatory standards, not all sunscreens are created equal and the formulations and protection capabilities differ from region to region. There are three main components necessary to create a sunscreen, which include UV filters, emollients, and emulsifiers. Some of the most common UV filters used in American products are zinc oxide, titanium dioxide, and octinoxate.

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Rank: 20
Score: 76.09952
Retrieved Text: Despite the recent changes in labeling mandated by the U.S. Food and Drug Administration (FDA), a recent study suggests the terminology on sunscreen labels may still be confusing consumers.
“We need to do a better job of educating people about sun protection and make it easier for them to understand labels,” said Dr. Roopal Kundu, lead author of the Northwestern University study "Assessment of Consumer Knowledge of New Sunscreen Labels” which appeared online in JAMA Dermatology ahead of print.
In this particular study involving 114 participants, only 43% understood the definition of the sun protection factor (SPF) value. (Dermatologists Answer Burning Questions About Sunscreens - Click here to read more).
Fewer than half (37.7%) were able to correctly identify the terminology that indicated how well the sunscreen protected against skin cancer, photoaging (7.0%) and sunburns (22.8%).
Most participants correctly identified higher SPF values as correlated with increased protection against sunburns (92.1%) and skin cancer (71.9%) but only 28.9% understood that it does not directly confer protection against photoaging.
Only 55.3% of participants correctly identified the amount of sunscreen needed to cover the entire body in order to achieve the advertised level of sun protection.
“Interestingly, participants who indicated ‘highest SPF available’ as an important factor in their sunscreen purchasing decision were less likely to answer this question correctly compared with those who did not consider SPF value to be an important factor,” the study said.
75.4% identified prevention of sunburns as an important factor in their decision to wear sunscreen, followed by preventing skin cancer (65.8%).
The top three influences in the participants’ decisions

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Retrieved Text: If you�ve bought sunscreen lately, you may have noticed that 70 is the new 15.
We used to feel safe with sunscreen labeled SPF 15. We thought �sun protection factor� 15 meant we could stay in the sun 15 times longer than we could with no sunscreen at all.
SPF numbers have less to do with time in the sun and more to do with the amount of harmful ultraviolet light making its way to your skin, according to the Food and Drug Administration. And now that SPF numbers are breaking into the triple digits � a handful of products boast a sun protection factor of 100 � the lowly SPF 15 sounds like a sunburn waiting to happen.
A hat is a good idea, particularly for men with thinning hair, Hughes says. And people with short hair must remember to put lotion on the tops of their ears, a vulnerable spot for sunburns and skin cancer.
Many of Hughes� patients are young people who have been diagnosed with melanoma, a skin cancer usually caused by too much exposure to the sun. Hughes teaches families good skin-care habits and fields plenty of questions about SPF numbers along the way.
SPF numbers are often misinterpreted. If you feel like doing the math, Hughes says, think of the SPF number as X times more coverage than no sunscreen at all. To figure out the percentage of harmful rays that SPF 15 absorbs, he says, divide 14 by 15. For SPF 30, divide 29 by 30. And so on.
You�ll discover that SPF 15 blocks

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Retrieved Text: For babies 6 months and older, or anyone in search of an ultra-gentle, fragrance-free mineral SPF stick.
Your little one's skin needs extra TLC. Our Mineral Baby SPF 50 Unscented Moisturizer is our purest lotion sunscreen, designed to safeguard the most precious and delicate skin.
People who love both makeup and great sun protection, and want to reapply SPF without it messing up their makeup, this is what you've been waiting for!
Protect your pucker with our Liplux® SPF 30 balm. This vitamin-enriched, antioxidant formula protects and conditions lips with a Peppermint Vanilla flavor.
Like FaceTune in a bottle, our Classic SPF 30 Dawn Patrol Makeup Primer helps your complexion look softer, smoother, and brighter—with or without makeup.
For anyone with dry, sunburned or just plain thirsty skin morning, noon and night.
Everyone needs a good A.M. moisturizer with sunscreen!
Mineral SPF shouldn't ghost you—this one nourishes and protects without leaving any white residue on your skin. SPF 30 moisturizing mineral sunscreen with antioxidant benefits.
This all-in-one lip treatment moisturizes and protects with broad spectrum UVA/UVB SPF 30 protection. This product is unscented, but you’ll still want to say MUAH!
Travelers or anyone who wants mini sizes of our mighty sun products. A pouch with four essential TSA-friendly size products inside!
Sun's out, fun's out! Our spray-on sunscreen is sheer with good-for-your-skin ingredients, plus it's organic SPF 30 and the perfect petite size to take with you.
Organic fans who love the outdoors! This is a broad-spectrum, SPF 50 moisturizing lotion sunscreen with antioxidants for enhanced UV protection.
Sun's out, fun's out! A sport sunscreen doesn't have to

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Rank: 23
Score: 75.591034
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Rank: 24
Score: 75.45602
Retrieved Text: Credits: "Artem Bali at Unsplash.com"
The sun is a necessary part of life, but too much sun exposure can be very harmful. Sun exposure can lead to skin damage, premature skin aging, and possibly over time, result in skin cancer. Over one million people in America are diagnosed with skin cancer each year from overexposure to the sun. Skin cancer is becoming one of the most common cancers in the United States, with an estimated 1 in 5 people who will get it during their lifetime. Sunscreen protection and refraining from sun exposure, in general, are more important than ever. Choosing the right sunscreen can often be confusing due to the sheer number of options that are out on the market.
What is SPF, and does it matter?
The simple answer is yes, SPF does matter. Sun Protection Factor, also known as SPF, is a measure of how well a sunscreen can protect human skin from the sun’s harmful UVB rays. More specifically, SPF refers to how well a sunscreen protects the skin from turning red and causing the colloquial “sunburn”.
Unfortunately, SPF cannot filter 100 percent of the rays but can get quite close. The strength of SPF you choose determines how well the skin will be protected. For example, SPF 15 filters 93 percent of UVB rays, SPF 30 filters out 97 percent, and SPF 50 filters 98 percent of rays. At some point, there is no real benefit to getting a higher SPF. It is recommended by the American Academy of Dermatology to utilize a sunscreen with

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Retrieved Text: Steps Every Man Needs to Follow When Applying Sunscreen.
Using sunscreen might not be as simple as you think: Most people hold inaccurate beliefs about their sunblock, new research from the American Academy of Dermatology (AAD) suggests.
And these misconceptions might leave you at greater risk of developing skin cancer.
In the survey, only 32 percent of respondents knew that an SPF 30 sunscreen does not provide twice as much protection as an SPF 15 sunscreen does.
In fact, the increase in protection from an SPF 15 to an SPF 30 isn’t very significant.
An SPF 30 blocks 97 percent of sunburn-causing UVB rays, while an SPF 15 blocks 93 percent, says Josh Zeichner, M.D., a spokesman for the AAD.
That means an SPF 30 blocks only 4 percent more UVB rays than SPF 15 does, a far cry from the “double” the numbers behind them would have you believe.
What’s more, just under half of those surveyed knew that a higher SPF sunscreen doesn’t protect you from the sun for a longer time than a lower SPF one does.
The real deal: Any sunscreen, no matter the SPF, wears off after two hours.
Putting too much faith in high SPF—whether it’s for amount of protection or how long you can safely stay in the sun—can be dangerous, since it can lead to a false sense of security regarding your burn risk, says Dr. Zeichner.
That may mean you might be more likely to stay in the sun for longer than you should or put off reapplying more sunscreen, which can make you more likely to

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Score: 74.91402
Retrieved Text: Dear Science: What does sunscreen SPF mean, and what happens if you mix them?
Dear Science: I'm gearing up for a summer vacation, and I've been burned before — so I want to make the most of all these half bottles of sunscreen left in my cabinet. If you mix equal amounts of SPF 10 sunscreen and SPF 30 sunscreen, do you get SPF 10, 20, 30 or 40? And what SPF should I be aiming for?
Step away from the mixing bowl, friend. Mixing sunscreens is a no-no. But it's important to understand why. First, let's get one thing out of the way: What the heck even is SPF?
According to Shari Lipner, dermatologist at Weill Cornell Medicine and NewYork-Presbyterian, your sunscreen's SPF (sun protection factor) does indeed tell you how much sun protection it can offer you. Researchers test sunscreen on bits of skin, comparing it with totally unprotected skin as they're both exposed to sunlight. SPF is a measurement of how much ultraviolet radiation — short, invisible wavelengths of light from the sun — is necessary to burn the sunscreened skin as compared with the unadorned flesh.
The numbers themselves refer to how long you can bake in the sun without burning: If it takes 20 minutes for your bare skin to start reddening, using an SPF 15 sunscreen is meant to let you have fun in the sun for 15 times longer – about five hours. But you still need to reapply it every two hours because of sweating and all that, so don't actually pay

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Retrieved Text: FAQs: Your Sunscreen Questions. Our Answers. Sunscreens: How it Works, What it Means.
Which sunscreens are best and why?
Is a good sunscreen all I need to be safe?
Doesn’t the government ensure that sunscreens protect us?
How much sunscreen is enough and how often should I reapply?
Will sunscreen protect me from cancer and wrinkling?
How high an SPF should I use?
Has using sunscreens lowered skin cancer rates?
Why shouldn’t I use sunscreen sprays and powders?
What about products that combine sunscreen with bug repellent?
I am using a good quality sunscreen with SPF 50, so why do I still get burned?
How do you remove sunscreen?
What should I do to protect my pet from the sun?
An ideal sunscreen would block the majority of UVA and UVB rays with active ingredients that do not break down in the sun, so that the product remains effective. It would also contain only active and inactive ingredients that are proven to be completely safe for both adults and children. No sunscreen on the U.S. market meets all these criteria and consumers have no simple way to know how well a given product stacks up. That’s why EWG created this guide to safer and more effective sunscreens.
No. Sunscreens can only provide partial protection against the harmful effects of the sun. Limiting sun exposure and wearing protective clothing are more important for protecting your skin from cancer and premature aging. Be extra careful about spending time in the sun between 10 a.m. and 4 p.m., when the sun’s rays are most intense. And remember that UVA radiation doesn’t decline as

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Retrieved Text: Easy sun protection tips with your loved ones this summer.
A video that shows exactly why we need to wear sunscreen.
“Yeah it is,” I agreed.
Just as an FYI, you should know that this post is sponsored by Nivea. But all opinions expressed by the author are 100% authentic and written in their own words.
As a child I roamed the NSW countryside with, maybe, one coat of SPF15. We never reapplied it and I now have arms covered in freckles and an aging face of pale skin as a constant reminder of my childhood.
In recent years we’ve been told to use sunscreen to protect ourselves from the harsh Australian sun, but do we really understand why? It wasn’t until I watched this video that I really understood it.
Filmed here in Australia, this clip shows exactly why we need to wear sunscreen – because the sun sees our skin differently when we apply it. Once you’ve seen the clip (I dare you not to watch it at least five times, it’s so fascinating) you truly can see how the sunscreen we use acts as a barrier helping to protect our skin from damage.
As someone with pale skin I’m constantly keeping up with skin care and sunscreen recommendations. I’m also constantly informing my friends and family about the difference between SPF 50 and SPF 30. The SPF (Sun Protection Factor) has absolutely nothing to do with strength but rather the amount of time you are protected.
Say you have pale skin like I do and you start to burn within three

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Retrieved Text: Is It Okay To Mix Foundation Makeup With My Daily Moisturizer?
Numerous people don’t like to wear heavy foundation makeup, but they feel the need for some coverage to even out their skin tone. They will mix a few drops of their foundation makeup with their daily moisturizer which creates a tinted moisturizer. Is this okay to do? Is this bad for my skin?
The goal of using daytime moisturizer is to use one with sunscreen; thus, both will provide your skin the protection against the sun’s UV rays, skin cancer, and premature wrinkles all while hydrating the skin. However, the FDA only guarantees the SPF of your sunscreen when used in its pure state. Changing the formula by adding foundation makeup may dilute the sunscreen’s protection, leaving your skin more exposed than intended.
I suggest that you use a sunscreen moisturizer that is compatible with your skin type along with a minimum SPF rating of 30. I suggest Weightless Protection SPF 30 You would also need a lightweight foundation makeup that you can apply over your sunscreen. There are many great formulas out there, but you need to spend the time to find the best combination that feels and looks right to you.
The #1 cause of wrinkles is sun exposure. Contrary to popular belief, genetics, smoking and surprisingly, the passage of time are not the biggest contributions to wrinkles compared to sun exposure. UV rays from sunlight are the skin’s worst enemy, so please be sure to protect it carefully.
Read: Does SPF 30 Protect Your Skin Twice As

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Input Text: Read the passage below and choose the right answer to the following question (choices are a greater number of isomers or fewer isomers? ):

The more carbon atoms a hydrocarbon has, the greater the number of isomers.


Compared to a hydrocarbon with a single carbon atom, would a hydrocarbon with 10 carbon atoms have a greater number of isomers or fewer isomers??

Target Text: a greater number of isomers

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Retrieved Text: A major class of organic compounds where carbon and hydrogen molecules are arranged in straight or branched chains. A type of hydrocarbon . Includes alkane s, alkene s, and alkyne s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where all of the carbon-carbon bonds are single bonds. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a double bond. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a triple bond. One of three major classes of aliphatic hydrocarbon s.
Molecules which are almost entirely carbon and hydrogen, but have had at least one chlorine atom introduced to them that has replaced one of their hydrogen atoms.
A hydrocarbon (molecule of carbon and hydrogen only) with 27 carbon atoms that is the parent structure of all mammalian steroid s.
Any of several enzyme s that put double bonds into the hydrocarbon areas of fatty acid s.
Any in a family of over 200 chlorinated organic chemicals (all heterocyclic hydrocarbons). The term is most commonly applied to a particular chemical, 2,3,7,8-tetrachlorodibenzo-paradioxin (2,3,7,8-TCDD, simply called TCDD), which is an impurity in the defoliant Agent Orange and in the pesticide 2,4,5-T (see auxin ). Dioxins are also produced when chlorinated materials such as plastics are burned. Dioxins are known to cause skin diseases (chloracne), birth defects, miscarriages, and cancer .
A

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Retrieved Text: Chapter L3 Section 4 Organic Compounds The Four Bonds of a Carbon Atom More than 90% of all compounds belong to a group called organic compounds. Organic compounds are covalent compounds composed of carbon-based molecules. Fuel, rubbing alcohol, sugar, cotton, paper and plastic belong to this group. All organic compounds contain carbon. Each carbon atom has four valence electrons so each carbon atom can make four bonds with four other atoms.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Carbon Backbones Structural formulas are models that are used to show how atoms in a molecule are connected. Each line represents a pair of electrons that form a covalent bond.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Many organic compounds are based on the types of carbon backbones shown below. Some compounds have hundreds or thousands of carbon atoms as part of their backbone.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Organic compounds may also contain hydrogen, oxygen, sulfur, nitrogen, and phosphorus. The next slide shows three models of carbon backbones.
Section 4 Organic Compounds Hydrocarbons and Other Organic Compounds Many organic compounds contain several kinds of atoms, but some contain only two. Organic compounds that contain only carbon and hydrogen are called hydrocarbons. There are three types of hydrocarbons: saturated hydrocarbons, unsaturated hydrocarbons, and aromatic hydrocarbons.
Chapter L3 Section 4 Organic Compounds Hydrocarbons, continued Saturated Hydrocarbons An alkane, or saturated hydrocarbon, is a hydrocarbon in which each carbon atom in the molecule shares a single bond with

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: Crude oil, as it is taken from the earth, is a very complex mixture of hydrocarbons.
As might be expected, the term hydrocarbon refers to the hydrogen and carbon atoms linked together and forming a majority of the individual molecules that are present. Having been transformed from living organisms being subject to heat and pressure over millions of years, the crude is termed to be an “organic” material. In addition to hydrogen and carbon, there are small amounts of other atomic elements that are present and mostly incorporated into the hydrocarbon molecules. The most common of these are nitrogen and sulfur. As part of the hydrocarbon, they are referred to as “hetero-” atoms. Heavier crude may also contain some inorganic materials such as nickel, vanadium, and iron, which are removed during refining.
Hydrocarbons form in an extraordinarily large number of configurations. They range in size from the simplest methane molecule, which contains one carbon atom and four hydrogens, to heavy asphaltic resins with structures that have not been fully mapped. Because we are dealing with mineral oil–based lubricants, we are interested in molecules of a size that fit into the range of approximately 15 to 95 carbon atoms long, corresponding roughly to a boiling range of about 300–700°C. In addition, as the number of carbon atoms in a molecule increase, the number of different ways that a molecule can be structured increases dramatically. Although many different arrangements of molecules may be imagined, for practical purposes, petroleum hydrocarbons are generally classified in a limited number of ways.
Consider the list

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: SCIENCE WAR research has produced various CAUSE --> EFFECT models that help explain some events....such as some accidents and deaths.
Here we shall look at the EARTH hydrocarbon continuum that humans live within.
Let's a background view established.
The astrophysics galactic LOCAL REGION (Planet Earth) is an interesting test location. A distant astrophysics observer ....... would see the earth as an atomic structure. Thus viewed, we could consider the astrophysics view of EARTH LAB events as atomic/molecular data events. In particular, physical chemistry --> social chemistry.
Thus ... we see that humans and humans institutions are subsets embedded within the atomic / astrophysics continuum .... an EARTH LAB atomic/astrophysics existential space .... an EARTH LAB atomic /astrophysics spectrum containing a variety of elements including human daily activities and events. Here, we concern ourselves with the hydrocarbon bandwidth (with humanoids) within Nature's larger existential continuum.
Let's look at a specific EARTH LAB case.
The organic chemistry hydrocarbon molecular WAR for control of the social chemistry institutions in the world ..... recently accomplished the assassination of Hugo Chavez via cancer.
With Hugo Chavez Dead, Will Chavismo Also Die?
Supporters of the late Venezuelan President Hugo Chavez cry in front of the ... hospitalized-- a day after his death in March 6, 2013, in Caracas.
The periodic atomic table used atomic mass communications to clearly imply the carbon atom ordered DEATH of Hugh Chavez ...under the auspices of disease. Mass communications is television, radio, newspaper publishing, print and graphic arts, the INTERNET computer information network, etc. For scientists ..mass communications is REALLY atomic mass communications .... that is

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Retrieved Text: Hydrocarbons containing at least three carbon atoms and non-aromatic carbon-to-hydrogen bonds are converted into hydrocarbons containing a new carbon-to-carbon linkage and having a higher carbon to hydrogen ratio by heating with an hydrogen-accepting olefine and a proportion of iodine (or hydrogen iodide, alkyl iodides or other compound which liberates iodine under the reaction conditions) of at least 0.05 mol. per mol. of hydrocarbon to be converted at at least 300 DEG C. to effect carbonto-hydrogen bond cleavage in the hydrocarbon feed and convert the olefine to paraffin. Conversions which may be effected are dehydrogenation of alkanes or aralkanes, e.g. isobutane to isobutene, n-butane to butenes and butadiene, ethyl benzene to styrene, o-methyl ethyl benzene to o-methyl styrene, and n-butyl benzene to 4 - phenyl - butadiene - 1,3; dehydrocoupling, e.g. propylene to diallyl, isobutene to dimethallyl, toluene to dibenzyl and stilbene; dehydrocyclization often with aromatization, e.g. n-hexane to benzene, n-heptane to toluene, n-octane to m-xylene and ethyl benzene, 2,5-dimethyl hexane to p-xylene, hexadiene-1,3 to benzene, hexane-1 to cyclohexene, o-diethylbenzene to naphthalene, o-methyl propyl benzene to naphthalene, n-butyl benzene to naphthalene, 2,3-diethyl naphthalene to anthracene, butylcyclohexane to naphthalene, and butylcyclopentane to indene; and dehydrogenation, often with aromatization of hydroaromatic hydrocarbons, e.g. cyclohexane to cyclohexene and benzene, and methylcyclohexane to toluene. In the case of acyclic hydrocarbons containing a quaternary carbon atom, dealkylation and/or isomerization may occur, e.g. 2,2,5-trimethylhexane gives p- and m-xylenes. The olefine used should be such that the sum of the standard free energy change for the hydrogenation of the olefine to the corresponding paraffin

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Retrieved Text: This article provides you the revision notes on Class 12 Chemistry: Chapter- Amines, to give you a quick glance of the chapter. These quick notes are prepared strictly according to the latest CBSE syllabus for Class 12th Chemistry.
Nitrogen atom of amines carries an unshared pair of electrons and is sp3 hybridised with pyramidal shape. Due to the presence of unshared pair of electrons, the angle C–N–E, (where E is C or H) is less than 109.5°.
In aromatic amines, the C‒N bond is slightly stronger due to the partial double bond character which arises as a result of delocalisation of lone pair of N with the benzene ring.
• 1° amine: One hydrogen atom of NH3 is replaced by an alkyl or aryl group.
• 2° amine: Two hydrogen atoms of NH3 are replaced by alkyl or aryl groups.
• 3° amine: All three hydrogen atoms of NH3 are replaced by alkyl or aryl groups.
• Aliphatic amines are named by prefixing an alkyl group to a mine, i.e., alkylamine.
• Secondary and tertiary amines, having two or more similar groups are named by adding prefix ‘di’ or ‘tri’ before the name of alkyl group.
• Aromatic amines are named as derivatives of the parent member, aniline (C6H5NH2).
• Aliphatic or aromatic amines are named by replacing ‘e’ in the end of the parent hydrocarbon by ‘amine’.
• Amines containing more than one amino groups at different positions in the parent chain, are named by specifying numbers to the carbon atoms bearing –NH2 groups along with attaching a suitable prefix such as di, tri, etc.

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Retrieved Text: Hydrocarbon, an organic chemical compound composed of carbon and hydrogen. Hydrocarbons may be gases, liquids, or solids. In nature, they are found mainly in plants, petroleum, natural gas, coal, and oil shale. Most burn readily and dissolve more readily in alcohol than in water. Some are toxic and some form an explosive mixture with air. Hydrocarbons are used as fuels and solvents and in the manufacture of industrial chemicals, explosives, plastics, synthetic rubber, dyes, drugs, and other products.
More than 100,000 hydrocarbons are known. The main reason there are so many of these compounds is that carbon atoms can unite in many different ways to form complex chain or ring frameworks. Different arrangements of atoms yield different molecules. For example, the formula C30 H62 (30 carbon atoms and 62 hydrogen atoms) represents 4,111,846,763 possible isomers—compounds whose molecules differ only in structure.
In chemistry, compounds closely related in structure to hydrocarbons are called hydrocarbon derivatives. Such compounds consist of carbon, hydrogen, and other elements, usually oxygen, nitrogen, chlorine, phosphorus, or sulfur. They are often named for the hydrocarbons to which they are most closely related. For example, the organic chloride compound most closely related to ethane is called ethyl chloride. Hydrocarbons and their derivatives form a large part of the subject matter of organic chemistry.
Hydrocarbons are divided into two main groups according to structure—aliphatic (or acyclic) hydrocarbons and cyclic hydrocarbons. They are further divided into groups of compounds having similar chemical properties. Members within a group are called homologs, and each complete group is called a homologous series. Neighboring

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Retrieved Text: Fuels Noaloil - NoalOil S.p.A.
Transport diesel complies with EN 590 European emission standards.To meet these standards, Directive 2009/30/EC requires that diesel should have a maximum sulphur content of 10 PPM (parts per million) and the biological component (biodiesel) can be anything up to 7% by volume.
European standard EN 228 is the reference standard for premium unleaded petrol with an octane rating of 95. Directive 2003/17/EC establishes the main requirements, such as sulphur levels (below 10 ppm) and octane rating (above 95).
Used as fuel, known as LPG (liquefied petroleum gas) it is composed primarily of a hydrocarbon mixture (propane and butane) obtained by refining crude oil or from extracted natural gas. These hydrocarbons become liquid under high pressures.
Formed by 1 carbon atom and 4 hydrogen atoms, methane is a simple hydrocarbon whose chemical formula is CH4. The form used for road transport is CNG (Compressed Natural Gas), a mixture of methane, propane and butane stored at 220 bar.
NOALOIL HIGH-SPEED DIESEL is a road transport diesel fuel that can be used on all diesel, eco-diesel and turbocharged engines.

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Retrieved Text: Kitchenlink Gas System Sdn Bhd is a gas piping system supplier company. Our main office is located in Puchong, Selangor, Malaysia. The company has been serving the gas piping industry for many years. We aim to deliver the highest quality service to our customers. If you would like any more information on the services we offer, please do not hesitate to contact us.
Natural gas is a gas that occurs deep beneath the earth’s surface. Natural gas consists mainly of methane, a gas (or compound) with one carbon atom and four hydrogen atoms. Natural gas also contains small amounts of hydrocarbon liquids and non-hydrocarbon gases. Natural gas can be used as a fuel or to make materials and chemicals.
• LPG is a mixture of two flammable but nontoxic gases called propane and butane. It is colourless and odourless in its natural state.
• LPG is heavier than air, unlike natural gas, and thus will flow along floors and tend to settle in low spots, such as basement.

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Retrieved Text: three molecules of fatty acids.
Each fatty acid consists of a hydrocarbon chain with a carboxyl group at one end. The glycerol molecule has three hydroxyl groups, each able to interact with the carboxyl group of a fatty acid. Removal of a water molecule at each of the three positions forms a triglyceride.
The three fatty acids in a single fat molecule may be all alike (as shown here for tristearin) or they may be different.
They may contain as few as 4 carbon atoms or as many as 24.
Because fatty acids are synthesized from fragments containing two carbon atoms, the number of carbon atoms in the chain is almost always an even number.
In animal fats, 16-carbon (palmitic acid) and 18-carbon (stearic acid - shown here) fatty acids are the most common.
Some fatty acids have one or more double bonds between their carbon atoms. They are called unsaturated because they could hold more hydrogen atoms than they do.
Monounsaturated fats have a single double bond in their fatty acids.
Polyunsaturated fats, such as trilinolein shown here, have two or more.
Double bonds are rigid and those in natural fats introduce a kink in the molecule. This prevents the fatty acids from packing close together and as a result, unsaturated fats have a lower melting point than do saturated fats. Because most of them are liquid at room temperature, we call them oils. Corn oil, canola oil, cottonseed oil, peanut oil, and olive oil are common examples.
As this list suggests, plant fats tend to be unsaturated (therefore "oils"). Fats from such animals as

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Retrieved Text: A fatty acid is a combination of a chain of carbon and hydrogen atoms, known as a hydrocarbon, and a particular acid group (-COOH). Three fatty-acid molecules combined with a glycerol form a triglyceride fat or oil.
While several varieties of fatty acid occur in nature, all belong in one of two categories—saturated or unsaturated. In a saturated fatty-acid molecule, all the carbon atoms in the chain are attached to two hydrogen atoms, the maximum amount. All the bonds between the carbon atoms in the chain are single electron bonds. An example of fat made of saturated fatty acids is butter.
Unsaturated fatty-acid molecules have one or more carbon atoms with only a single hydrogen atom attached. In these chains, one or more bonds between the carbon atoms are double. A molecule with one double bond is called monounsaturated, and two or more double bonds is called polyunsaturated. An example of unsaturated fat is vegetable oil.
Generally, fats consisting of saturated fatty acids are solid, and those made up of unsaturated molecules are liquid. An unsaturated fatty acid may be converted into saturated through a process called hydrogenation. While most modern diets are aimed at the reduction of fatty acids (fats), it is important to recognize that several of them, such as oleic, butyric, and palmitic acid, are important parts of the human diet. Another, linoleic acid, is absolutely essential to human life. It is an important part of a vital chemical reaction in the body, and is obtained solely through ingestion. It is found in corn, soybean, and

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Retrieved Text: This page deals briefly with the combustion of alkanes and cycloalkanes. In fact, there is very little difference between the two.
Complete combustion (given sufficient oxygen) of any hydrocarbon produces carbon dioxide and water. It is quite important that you can write properly balanced equations for these reactions, because they often come up as a part of thermochemistry calculations. Some are easier than others. For example, with alkanes, the ones with an even number of carbon atoms are marginally harder than those with an odd number!
With butane (C4H10), you can again balance the carbons and hydrogens as you write the equation down.
Counting the oxygens leads to a slight problem - with 13 on the right-hand side. The simple trick is to allow yourself to have "six-and-a-half" O2 molecules on the left.
The hydrocarbons become harder to ignite as the molecules get bigger. This is because the bigger molecules don't vaporize so easily - the reaction is much better if the oxygen and the hydrocarbon are well mixed as gases. If the liquid is not very volatile, only those molecules on the surface can react with the oxygen. Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbors and turn to a gas.
Provided the combustion is complete, all the hydrocarbons will burn with a blue flame. However, combustion tends to be less complete as the number of carbon atoms in the molecules rises. That means that the bigger the hydrocarbon, the more likely you are to get a

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Retrieved Text: Any organic compound composed only of carbon and hydrogen.
Any organic compound composed only of carbon and hydrogen. Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.
Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: (Nanowerk News) Chemists at The Scripps Research Institute (TSRI) have developed a broadly useful technique for building new drug molecules and other chemical products.
The technique, reported March 9, 2015 as an Advance Online paper by the journal Nature ("Ligand-Enabled meta-C-H Activation Using a Transient Mediator"), is an improved, easier method for "meta-C-H activation," the attachment of a desired group of atoms to a particularly hard-to-reach position on the carbon backbone of an organic molecule.
"This method can be used for the synthesis of small quantities, for example to discover potential new drug compounds, and also for bulk manufacturing," said Jin-Quan Yu, the Frank and Bertha Hupp Professor of Chemistry at TSRI.
Yu's laboratory specializes in finding better ways to build organic molecules and has now published five such innovations in Nature or Science over the past year. These highly technical methods generally pass under the radar of popular science news, but academic and professional chemists have been adopting them enthusiastically, using them to develop next-generation drugs and other novel chemical products.
A better method for meta-C-H activation should be especially welcome, given the traditional difficulty of that feat.
C-H activation means breaking a bond between a carbon and a hydrogen atom--hydrogen atoms being the default attachments to carbons in simple hydrocarbon molecules--and replacing the hydrogen with something else. Usually that something else is a more reactive cluster of atoms called a functional group, which helps give the resulting molecule its desired properties.
Chemists who build molecules using C-H activations often use an existing functional group on a hydrocarbon to facilitate the

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Retrieved Text: With rare exceptions, until now every reaction we’ve discussed (acid-base, substitution, elimination, addition) has involved the formation of bonds between an electron pair donor (Lewis base) and an electron pair acceptor (Lewis acid) or the breakage of bonds to generate the same [this is called “heterolytic” cleavage, by the way, since one bonding partner gets two electrons and the other gets zero].
In this series of posts we’ll take a detour into a corner of organic chemistry where bonds are formed by the combination of single electrons and bonds break through “homolytic” cleavage [that is, each bonding partner receives an equal number of electrons]. As we’ll see, these reactions are generally referred to as free radicals.
It all starts with a simple observation. Take an ordinary hydrocarbon gas – methane, for example, although any alkane hydrocarbon will be suitable here. When we combine this hydrocarbon with chlorine gas, in the dark, nothing happens.
Here’s the interesting part. Flick a switch – or remove the cover – such that visible light can enter the flask, and suddenly our methane is consumed such that carbon-hydrogen bonds are replaced with carbon-chlorine bonds. The final product depends on the number of equivalents of chlorine gas – let’s use Cl2 in very small quantities to start with, to keep things simple.
What’s going on here? Note that “hv” means “light”. [We can also do this reaction with heat alone, although it requires higher temperatures].
Before trying to understand why this happened, let’s make sure we’re clear on what has happened.
Let’s look at what bonds have formed

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Retrieved Text: Carbon Monoxide Is A Deadly Gas That Can Kill! Keep Your Family Safe With A Carbon Monixide Detector and smoke detectors.One of the first lines of defense against deadly fires and smoke, is having working smoke alarms throughout your home and living area. A second very important monitoring device to have in your home is a carbon monoxide detector.What is Carbon Monoxide?Carbon monoxide (CO) is a colorless, odorless, poisonous gas. A product of incomplete burning of hydrocarbon-based fuels, carbon monoxide consists of a carbon atom.

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Retrieved Text: (organic compound) An alicyclic hydrocarbon, C6H12, consisting of a ring of six carbon atoms; a volatile liquid.
Supplemental Details:Sponsor an extended definition for cyclohexane for as little as $10 per month. Click here to contact us.

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Retrieved Text: Covalent bond or Molecular bond or Homopolar bond : A chemical bond formed between two non-metallic elements by the mutual sharing of one or more electron pairs is called covalent bond.
Covalency : The number of electron pairs which an atom of an element mutually shares with another atom or atoms of the same or different elements, so as to acquire a stable configuration like noble gases, is called co valency.
Properties of covalent (molecular) compound : (i) They have low melting point and boiling point. (ii) They have low density, i.e., their density is generally less than that of water. (iii) They are gaseous or volatile liquids or soft solids. (iv) They are insoluble in water, but soluble in organic solvents. (v) They are generally bad conductors of electricity.
Diamond is the purest crystalline form of carbon which is the hardest naturally occurring substance.
Other pure crystalline forms of carbon are graphite and fullerenes. In Buckminster- fullerene, each molecule has 60 atoms arranged in hexagons and pentagons.
Organic Chemistry : The branch of chemistry dealing with carbon compounds other than carbon monoxide, carbon dioxide and carbonates is called organic chemistry.
Catenation : The property of carbon atoms to link with other carbon atoms or the atoms of other elements with single, double or triple covalent bonds, so as to form large number of compounds is called catenation.
Saturated organic compounds : Organic compounds in which all the four valencies of carbon atoms are satisfied by single covalent bonds, are called saturated organic compounds.
Unsaturated organic compounds : Organic compounds in which a double

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Retrieved Text: Hydrocarbons and carbohydrates should not be confused. Hydrocarbons contain hydrogen and carbon only. Carbohydrates contain these two elements, but they also contain oxygen. In fact the "ate" suffix in chemistry implies oxygen. I'm sure you've heard of: carbonate (CO3), sulfate (SO4), phosphate (PO4), nitrate (NO3), and silicate (SiO4). These are not complete molecules - they are fragments, polyatomic anions to be precise, that are typically paired with metals to make salts or minerals, or with hydrogen to produce acids. Thus calcium carbonate, the principal component of limestone, or marble when compressed and heated over geologic time, is CaCO3. This "ate" nomenclature may help you remember that carbohydrates contain oxygen, and are a much more complicated molecule. In fact carbohydrates, along with proteins and fats, form the basis of food. These are the three macronutrients, as described earlier.
Since hydrocarbons contain only hydrogen and carbon, their structure is much simpler. In fact, the properties of a hydrocarbon molecule are determined, primarily, by the number of carbons. The simplest example has one carbon, surrounded by four hydrogens, and is called methane. It is a small, light, symmetric molecule, hence it is a gas. It does not liquify until -161C, or -258F. You've probably been out in weather that is subzero, but temperatures this cold are simply unimaginable.
The above representation is somewhat misleading, because it squashes the methane molecule onto the 2 dimensional page. Most molecules have a 3 dimensional structure. The carbon atom has four electrons in its outermost shell, four valence electrons, four bonds that must be satisfied.

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Retrieved Text: The terpene synthase discovered in this study consists of the prenyltransferase (PT) domain that synthesizesthe 20-carbon linear compound (GGPP) and the terpene cyclase domain that transforms GGPP into a cyclized hydrocarbon. By domain swapping of the PT with that which synthesizes the 25-carbon compound (GFPP), another molecule was successfully obtained.
A research group at the University of Tokyo has discovered and described the function of a unique enzyme involved in the biosynthesis of terpene (terpenoid) natural products, and successfully altered its function by altering its structure so that the enzyme produces another molecule.
Terpenoids are natural products synthesized from five-carbon isoprene units as building blocks, and include pharmaceutically important compounds such as the anticancer drug paclitaxel and antimalarial agent artemisinin. Terpenoids are synthesized by plants, microorganisms, and animals with the aid of enzymes.
The research group of Assistant Professor Yudai Matsuda and Professor Ikuro Abe at Graduate School of Pharmaceutical Sciences, The University of Tokyo, has identified a new terpene synthase from filamentous fungi that synthesizes a diterpene (terpene consisting of 20 carbon atoms) hydrocarbon with a novel molecular architecture. It is notable that the enzyme has two distinct domains; one is the prenyltransferase (PT) domain synthesizing the 20-carbon linear compound (GGPP) from five-carbon isoprene units, and the other one is the terpene cyclase (TC) domain that cyclizes the linear substrate into the final product. Thus, the terpene synthase is just like the Chimera in Greek mythology as two enzymes are fused as a single protein.
Although several similar multitasking enzymes have been described prior to this study, an attempt

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Retrieved Text: Miscibility /mɪsᵻˈbɪlᵻti/ is the property of substances to mix in all proportions, forming a homogeneous solution. The term is most often applied to liquids, but applies also to solids and gases. Water and ethanol, for example, are miscible because they mix in all proportions.
By contrast, substances are said to be immiscible if a significant proportion does not form a solution. Otherwise, the substances are considered miscible. For example, butanone is significantly soluble in water, but these two solvents are not miscible because they are not soluble in all proportions.
In organic compounds, the weight percent of hydrocarbon chain often determines the compound's miscibility with water. For example, among the alcohols, ethanol has two carbon atoms and is miscible with water, whereas 1-octanol with eight carbons is not. Octanol's immiscibility leads it to be used as a standard for partition equilibria. This is also the case with lipids; the very long carbon chains of lipids cause them almost always to be immiscible with water. Analogous situations occur for other functional groups. Acetic acid (CH3COOH) is miscible with water, whereas valeric acid (C4H9COOH) is not. Simple aldehydes and ketones tend to be miscible with water, because a hydrogen bond can form between the hydrogen atom of a water molecule and the unbonded (lone) pair of electrons on the carbonyl oxygen atom.

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Retrieved Text: · Instead of gaining and loosing electrons, carbon shares its 4-electrons with another element or carbon to form molecule.
· Covalent bonds are formed as a result of sharing of electrons. Example- H2, O2, N2. Covalent compounds have low melting point and boiling point due to small intermolecular forces.
· H2forms by sharing valence electrons (1 per atom of H) and produce single bond between two hydrogen atoms.
· O2 forms by sharing valence electrons (2 per atom of O) and produce double bond between two oxygen atoms.
· N2forms by sharing valence electrons (3 per atom of N) and produce triple bond between two nitrogen atoms.
· Methane, CH4is simple carbon compounds and used as a fuel on large scale and also a major component of CNG (Compressed Natural Gas). Methane formed due to sharing of 4 valence electrons of carbon with 4 hydrogen atoms.
Carbon have three allotropes i.e. Diamond, Graphite and fullerene.
Diamond formed due to rigid three dimensional structures of carbon atoms because each carbon atom bonded to another 4 carbon atoms. It is hardest substance.
Graphite formed due to presence of hexagonal array layers above one another, and layers of hexagonal arrays formed because each carbon atom bonded to another 3 carbon atoms with 2 single and 1 double bond. It is smooth, slippery and very good conductor of electricity.
Fullerenes (C-60) are also an allotrope of carbon in which carbon atoms are arranged in football like shape.
Carbon shows versatile nature because it has two characteristics features which are catenation and tetravalency. These both feature gives large numbers of compounds.
Catenation

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: Olefin content is an important factor in fuel production. But what exactly are olefins? In short, they’re an unsaturated hydrocarbon. Of course, there’s more to the story than that alone. Read on as we take a closer look at olefins – where they come from, what they’re made up of and why they’re important.
Olefin is a compound comprising hydrogen and carbon, with at least one pair of carbon atoms. Those atoms are linked by a double bond, which – along with the hydrogen and carbon content – makes them an unsaturated hydrocarbon.
Also known as alkene, olefins can vary in the number of double bonds per molecule, making them mono-olefins, diolefins, triolefins and so forth. They can also be categorised as either cyclic or acyclic. Cyclic olefins have a double bond between carbon atoms which makes up a closed ring of compounds. On the other hand, acyclic olefins form an open-chain group.
Where do olefins come from?
One of the earliest processes where olefins were produced came in the early 1900s through thermal cracking. This technique uses high temperatures and high pressure to break up large hydrocarbons into smaller compounds. They can also be produced by other forms of cracking, such as hydrocracking and fluid catalytic cracking.
Both petrol and diesel contain several different hydrocarbon molecules. Paraffins, olefins and aromatics account form most hydrocarbons in petrol, while diesel is mostly paraffins, aromatics and naphthenes.
Paraffins can improve the ignition quality of fuels, but can have low-termperature resistance. On the other hand, aromatics have high octane numbers – meaning the fuel can

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Retrieved Text: Lipids are nonpolar organic molecules that are insoluble in polar water but soluble in nonpolar organic solvents like ether, alcohol, and chloroform. Lipids show hydrophobic behavior. The behaviour is associated with the chemical structures of lipids. Lipids have high proportion of C-1-I bonds. C-1-I is non-polar in character. Phospholipids and cholesterol are lipids. They are important constituents of cell membranes. The most common lipids in plants and animals are fats.
oxygen atoms. Some figs also contain small amounts of phosphorus and nitrogen. They contain a much smaller proportion of oxygen than carbohydrates. For example the formula of the fat tristearin is C5,F111006.
The building blocks of fat molecules are fatty acids and glycerol. Fatty acids contain long hydrocarbon chains bonded to carboxyl (COOH) groups. Glycerol is a three-carbon alcohol, with each carbon bearing a hydroxyl (OH) group. Three fatty acid molecules combine with one glycerol molecule. They are attached to the three carbon atoms in the glycerol backbone.
The fats with three fatty acids are called triglyceride neutral fat or triacylglycerol. The glycerol portion of every fat molecule is the same. But there are many kinds of fatty acids. Therefore, there are many kinds of fats. Fatty acid molecules differ in the length of their carbon chains aud in the ways the carbon atoms combine. The most common are e :en-numbered chains of 14 to 20 carbons.
Unsaturated fats: The% have double bonds. Their chains bend at the double bonds. So the fat molecules cannot align closely w ith one another. Therefore. they have low melting points. Thus the fat

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Retrieved Text: There are 5 lectures in this section of science wherein you are going to learn about Carbon and its compound. This is a very important chapter of Science and accounts for about 23 marks with periodic classification of elements. In Carbon and its compound You will learn the following as per the syllabus: Covalent bonding in carbon compounds. Versatile nature of carbon. Homologous series, Nomenclature of carbon compounds containing functional groups (halogens, alcohol, ketones, aldehydes, alkanes and alkynes), difference between saturated hydrocarbons and unsaturated hydrocarbons. Chemical properties of carbon compounds (combustion, oxidation, addition and substitution reaction). Ethanol and Ethanoic acid (only properties and uses), soaps and detergents.
This is first lecture of the Carbon and its compound which is the fourth chapter and is very important for SA-2 as it covers about 15-18 marks in exams. In this session you will learn about the Carbon and its properties. As you know carbon is an element and it has 4 valence electrons in its outermost shell, its valence electron are responsible for the entire change in the behavior and thus it forms maximum number of compounds. You will study here the terms covalency, catenation, tetravalency. The you will learn about the occurrence of Carbon. Sharing of electrons by Carbon. Then you will study the properties of hydrogen and how it forms compounds with hydrogen.Occurrence of allotropes of Carbon i.e.,Diamond, Graphite and Buckministerfulerene. You will study the properties of all three isotopes and difference among the three. You will also discuss the term Allotrophy, organic, Inorganic compound, saturated and

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Input Text: Read the passage below and choose the right answer to the following question (choices are a greater number of isomers or fewer isomers? ):

The more carbon atoms a hydrocarbon has, the greater the number of isomers.


Compared to a hydrocarbon with 10 carbon atoms, would a hydrocarbon with a single carbon atom have a greater number of isomers or fewer isomers??

Target Text: fewer isomers?

#### Retrieved Documents ####

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Retrieved Text: A major class of organic compounds where carbon and hydrogen molecules are arranged in straight or branched chains. A type of hydrocarbon . Includes alkane s, alkene s, and alkyne s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where all of the carbon-carbon bonds are single bonds. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a double bond. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a triple bond. One of three major classes of aliphatic hydrocarbon s.
Molecules which are almost entirely carbon and hydrogen, but have had at least one chlorine atom introduced to them that has replaced one of their hydrogen atoms.
A hydrocarbon (molecule of carbon and hydrogen only) with 27 carbon atoms that is the parent structure of all mammalian steroid s.
Any of several enzyme s that put double bonds into the hydrocarbon areas of fatty acid s.
Any in a family of over 200 chlorinated organic chemicals (all heterocyclic hydrocarbons). The term is most commonly applied to a particular chemical, 2,3,7,8-tetrachlorodibenzo-paradioxin (2,3,7,8-TCDD, simply called TCDD), which is an impurity in the defoliant Agent Orange and in the pesticide 2,4,5-T (see auxin ). Dioxins are also produced when chlorinated materials such as plastics are burned. Dioxins are known to cause skin diseases (chloracne), birth defects, miscarriages, and cancer .
A

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Retrieved Text: Chapter L3 Section 4 Organic Compounds The Four Bonds of a Carbon Atom More than 90% of all compounds belong to a group called organic compounds. Organic compounds are covalent compounds composed of carbon-based molecules. Fuel, rubbing alcohol, sugar, cotton, paper and plastic belong to this group. All organic compounds contain carbon. Each carbon atom has four valence electrons so each carbon atom can make four bonds with four other atoms.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Carbon Backbones Structural formulas are models that are used to show how atoms in a molecule are connected. Each line represents a pair of electrons that form a covalent bond.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Many organic compounds are based on the types of carbon backbones shown below. Some compounds have hundreds or thousands of carbon atoms as part of their backbone.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Organic compounds may also contain hydrogen, oxygen, sulfur, nitrogen, and phosphorus. The next slide shows three models of carbon backbones.
Section 4 Organic Compounds Hydrocarbons and Other Organic Compounds Many organic compounds contain several kinds of atoms, but some contain only two. Organic compounds that contain only carbon and hydrogen are called hydrocarbons. There are three types of hydrocarbons: saturated hydrocarbons, unsaturated hydrocarbons, and aromatic hydrocarbons.
Chapter L3 Section 4 Organic Compounds Hydrocarbons, continued Saturated Hydrocarbons An alkane, or saturated hydrocarbon, is a hydrocarbon in which each carbon atom in the molecule shares a single bond with

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: Crude oil, as it is taken from the earth, is a very complex mixture of hydrocarbons.
As might be expected, the term hydrocarbon refers to the hydrogen and carbon atoms linked together and forming a majority of the individual molecules that are present. Having been transformed from living organisms being subject to heat and pressure over millions of years, the crude is termed to be an “organic” material. In addition to hydrogen and carbon, there are small amounts of other atomic elements that are present and mostly incorporated into the hydrocarbon molecules. The most common of these are nitrogen and sulfur. As part of the hydrocarbon, they are referred to as “hetero-” atoms. Heavier crude may also contain some inorganic materials such as nickel, vanadium, and iron, which are removed during refining.
Hydrocarbons form in an extraordinarily large number of configurations. They range in size from the simplest methane molecule, which contains one carbon atom and four hydrogens, to heavy asphaltic resins with structures that have not been fully mapped. Because we are dealing with mineral oil–based lubricants, we are interested in molecules of a size that fit into the range of approximately 15 to 95 carbon atoms long, corresponding roughly to a boiling range of about 300–700°C. In addition, as the number of carbon atoms in a molecule increase, the number of different ways that a molecule can be structured increases dramatically. Although many different arrangements of molecules may be imagined, for practical purposes, petroleum hydrocarbons are generally classified in a limited number of ways.
Consider the list

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: SCIENCE WAR research has produced various CAUSE --> EFFECT models that help explain some events....such as some accidents and deaths.
Here we shall look at the EARTH hydrocarbon continuum that humans live within.
Let's a background view established.
The astrophysics galactic LOCAL REGION (Planet Earth) is an interesting test location. A distant astrophysics observer ....... would see the earth as an atomic structure. Thus viewed, we could consider the astrophysics view of EARTH LAB events as atomic/molecular data events. In particular, physical chemistry --> social chemistry.
Thus ... we see that humans and humans institutions are subsets embedded within the atomic / astrophysics continuum .... an EARTH LAB atomic/astrophysics existential space .... an EARTH LAB atomic /astrophysics spectrum containing a variety of elements including human daily activities and events. Here, we concern ourselves with the hydrocarbon bandwidth (with humanoids) within Nature's larger existential continuum.
Let's look at a specific EARTH LAB case.
The organic chemistry hydrocarbon molecular WAR for control of the social chemistry institutions in the world ..... recently accomplished the assassination of Hugo Chavez via cancer.
With Hugo Chavez Dead, Will Chavismo Also Die?
Supporters of the late Venezuelan President Hugo Chavez cry in front of the ... hospitalized-- a day after his death in March 6, 2013, in Caracas.
The periodic atomic table used atomic mass communications to clearly imply the carbon atom ordered DEATH of Hugh Chavez ...under the auspices of disease. Mass communications is television, radio, newspaper publishing, print and graphic arts, the INTERNET computer information network, etc. For scientists ..mass communications is REALLY atomic mass communications .... that is

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Retrieved Text: Hydrocarbons containing at least three carbon atoms and non-aromatic carbon-to-hydrogen bonds are converted into hydrocarbons containing a new carbon-to-carbon linkage and having a higher carbon to hydrogen ratio by heating with an hydrogen-accepting olefine and a proportion of iodine (or hydrogen iodide, alkyl iodides or other compound which liberates iodine under the reaction conditions) of at least 0.05 mol. per mol. of hydrocarbon to be converted at at least 300 DEG C. to effect carbonto-hydrogen bond cleavage in the hydrocarbon feed and convert the olefine to paraffin. Conversions which may be effected are dehydrogenation of alkanes or aralkanes, e.g. isobutane to isobutene, n-butane to butenes and butadiene, ethyl benzene to styrene, o-methyl ethyl benzene to o-methyl styrene, and n-butyl benzene to 4 - phenyl - butadiene - 1,3; dehydrocoupling, e.g. propylene to diallyl, isobutene to dimethallyl, toluene to dibenzyl and stilbene; dehydrocyclization often with aromatization, e.g. n-hexane to benzene, n-heptane to toluene, n-octane to m-xylene and ethyl benzene, 2,5-dimethyl hexane to p-xylene, hexadiene-1,3 to benzene, hexane-1 to cyclohexene, o-diethylbenzene to naphthalene, o-methyl propyl benzene to naphthalene, n-butyl benzene to naphthalene, 2,3-diethyl naphthalene to anthracene, butylcyclohexane to naphthalene, and butylcyclopentane to indene; and dehydrogenation, often with aromatization of hydroaromatic hydrocarbons, e.g. cyclohexane to cyclohexene and benzene, and methylcyclohexane to toluene. In the case of acyclic hydrocarbons containing a quaternary carbon atom, dealkylation and/or isomerization may occur, e.g. 2,2,5-trimethylhexane gives p- and m-xylenes. The olefine used should be such that the sum of the standard free energy change for the hydrogenation of the olefine to the corresponding paraffin

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Retrieved Text: This article provides you the revision notes on Class 12 Chemistry: Chapter- Amines, to give you a quick glance of the chapter. These quick notes are prepared strictly according to the latest CBSE syllabus for Class 12th Chemistry.
Nitrogen atom of amines carries an unshared pair of electrons and is sp3 hybridised with pyramidal shape. Due to the presence of unshared pair of electrons, the angle C–N–E, (where E is C or H) is less than 109.5°.
In aromatic amines, the C‒N bond is slightly stronger due to the partial double bond character which arises as a result of delocalisation of lone pair of N with the benzene ring.
• 1° amine: One hydrogen atom of NH3 is replaced by an alkyl or aryl group.
• 2° amine: Two hydrogen atoms of NH3 are replaced by alkyl or aryl groups.
• 3° amine: All three hydrogen atoms of NH3 are replaced by alkyl or aryl groups.
• Aliphatic amines are named by prefixing an alkyl group to a mine, i.e., alkylamine.
• Secondary and tertiary amines, having two or more similar groups are named by adding prefix ‘di’ or ‘tri’ before the name of alkyl group.
• Aromatic amines are named as derivatives of the parent member, aniline (C6H5NH2).
• Aliphatic or aromatic amines are named by replacing ‘e’ in the end of the parent hydrocarbon by ‘amine’.
• Amines containing more than one amino groups at different positions in the parent chain, are named by specifying numbers to the carbon atoms bearing –NH2 groups along with attaching a suitable prefix such as di, tri, etc.

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Retrieved Text: Hydrocarbon, an organic chemical compound composed of carbon and hydrogen. Hydrocarbons may be gases, liquids, or solids. In nature, they are found mainly in plants, petroleum, natural gas, coal, and oil shale. Most burn readily and dissolve more readily in alcohol than in water. Some are toxic and some form an explosive mixture with air. Hydrocarbons are used as fuels and solvents and in the manufacture of industrial chemicals, explosives, plastics, synthetic rubber, dyes, drugs, and other products.
More than 100,000 hydrocarbons are known. The main reason there are so many of these compounds is that carbon atoms can unite in many different ways to form complex chain or ring frameworks. Different arrangements of atoms yield different molecules. For example, the formula C30 H62 (30 carbon atoms and 62 hydrogen atoms) represents 4,111,846,763 possible isomers—compounds whose molecules differ only in structure.
In chemistry, compounds closely related in structure to hydrocarbons are called hydrocarbon derivatives. Such compounds consist of carbon, hydrogen, and other elements, usually oxygen, nitrogen, chlorine, phosphorus, or sulfur. They are often named for the hydrocarbons to which they are most closely related. For example, the organic chloride compound most closely related to ethane is called ethyl chloride. Hydrocarbons and their derivatives form a large part of the subject matter of organic chemistry.
Hydrocarbons are divided into two main groups according to structure—aliphatic (or acyclic) hydrocarbons and cyclic hydrocarbons. They are further divided into groups of compounds having similar chemical properties. Members within a group are called homologs, and each complete group is called a homologous series. Neighboring

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Retrieved Text: Fuels Noaloil - NoalOil S.p.A.
Transport diesel complies with EN 590 European emission standards.To meet these standards, Directive 2009/30/EC requires that diesel should have a maximum sulphur content of 10 PPM (parts per million) and the biological component (biodiesel) can be anything up to 7% by volume.
European standard EN 228 is the reference standard for premium unleaded petrol with an octane rating of 95. Directive 2003/17/EC establishes the main requirements, such as sulphur levels (below 10 ppm) and octane rating (above 95).
Used as fuel, known as LPG (liquefied petroleum gas) it is composed primarily of a hydrocarbon mixture (propane and butane) obtained by refining crude oil or from extracted natural gas. These hydrocarbons become liquid under high pressures.
Formed by 1 carbon atom and 4 hydrogen atoms, methane is a simple hydrocarbon whose chemical formula is CH4. The form used for road transport is CNG (Compressed Natural Gas), a mixture of methane, propane and butane stored at 220 bar.
NOALOIL HIGH-SPEED DIESEL is a road transport diesel fuel that can be used on all diesel, eco-diesel and turbocharged engines.

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Retrieved Text: Kitchenlink Gas System Sdn Bhd is a gas piping system supplier company. Our main office is located in Puchong, Selangor, Malaysia. The company has been serving the gas piping industry for many years. We aim to deliver the highest quality service to our customers. If you would like any more information on the services we offer, please do not hesitate to contact us.
Natural gas is a gas that occurs deep beneath the earth’s surface. Natural gas consists mainly of methane, a gas (or compound) with one carbon atom and four hydrogen atoms. Natural gas also contains small amounts of hydrocarbon liquids and non-hydrocarbon gases. Natural gas can be used as a fuel or to make materials and chemicals.
• LPG is a mixture of two flammable but nontoxic gases called propane and butane. It is colourless and odourless in its natural state.
• LPG is heavier than air, unlike natural gas, and thus will flow along floors and tend to settle in low spots, such as basement.

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Retrieved Text: three molecules of fatty acids.
Each fatty acid consists of a hydrocarbon chain with a carboxyl group at one end. The glycerol molecule has three hydroxyl groups, each able to interact with the carboxyl group of a fatty acid. Removal of a water molecule at each of the three positions forms a triglyceride.
The three fatty acids in a single fat molecule may be all alike (as shown here for tristearin) or they may be different.
They may contain as few as 4 carbon atoms or as many as 24.
Because fatty acids are synthesized from fragments containing two carbon atoms, the number of carbon atoms in the chain is almost always an even number.
In animal fats, 16-carbon (palmitic acid) and 18-carbon (stearic acid - shown here) fatty acids are the most common.
Some fatty acids have one or more double bonds between their carbon atoms. They are called unsaturated because they could hold more hydrogen atoms than they do.
Monounsaturated fats have a single double bond in their fatty acids.
Polyunsaturated fats, such as trilinolein shown here, have two or more.
Double bonds are rigid and those in natural fats introduce a kink in the molecule. This prevents the fatty acids from packing close together and as a result, unsaturated fats have a lower melting point than do saturated fats. Because most of them are liquid at room temperature, we call them oils. Corn oil, canola oil, cottonseed oil, peanut oil, and olive oil are common examples.
As this list suggests, plant fats tend to be unsaturated (therefore "oils"). Fats from such animals as

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Retrieved Text: A fatty acid is a combination of a chain of carbon and hydrogen atoms, known as a hydrocarbon, and a particular acid group (-COOH). Three fatty-acid molecules combined with a glycerol form a triglyceride fat or oil.
While several varieties of fatty acid occur in nature, all belong in one of two categories—saturated or unsaturated. In a saturated fatty-acid molecule, all the carbon atoms in the chain are attached to two hydrogen atoms, the maximum amount. All the bonds between the carbon atoms in the chain are single electron bonds. An example of fat made of saturated fatty acids is butter.
Unsaturated fatty-acid molecules have one or more carbon atoms with only a single hydrogen atom attached. In these chains, one or more bonds between the carbon atoms are double. A molecule with one double bond is called monounsaturated, and two or more double bonds is called polyunsaturated. An example of unsaturated fat is vegetable oil.
Generally, fats consisting of saturated fatty acids are solid, and those made up of unsaturated molecules are liquid. An unsaturated fatty acid may be converted into saturated through a process called hydrogenation. While most modern diets are aimed at the reduction of fatty acids (fats), it is important to recognize that several of them, such as oleic, butyric, and palmitic acid, are important parts of the human diet. Another, linoleic acid, is absolutely essential to human life. It is an important part of a vital chemical reaction in the body, and is obtained solely through ingestion. It is found in corn, soybean, and

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Retrieved Text: This page deals briefly with the combustion of alkanes and cycloalkanes. In fact, there is very little difference between the two.
Complete combustion (given sufficient oxygen) of any hydrocarbon produces carbon dioxide and water. It is quite important that you can write properly balanced equations for these reactions, because they often come up as a part of thermochemistry calculations. Some are easier than others. For example, with alkanes, the ones with an even number of carbon atoms are marginally harder than those with an odd number!
With butane (C4H10), you can again balance the carbons and hydrogens as you write the equation down.
Counting the oxygens leads to a slight problem - with 13 on the right-hand side. The simple trick is to allow yourself to have "six-and-a-half" O2 molecules on the left.
The hydrocarbons become harder to ignite as the molecules get bigger. This is because the bigger molecules don't vaporize so easily - the reaction is much better if the oxygen and the hydrocarbon are well mixed as gases. If the liquid is not very volatile, only those molecules on the surface can react with the oxygen. Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbors and turn to a gas.
Provided the combustion is complete, all the hydrocarbons will burn with a blue flame. However, combustion tends to be less complete as the number of carbon atoms in the molecules rises. That means that the bigger the hydrocarbon, the more likely you are to get a

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Retrieved Text: Any organic compound composed only of carbon and hydrogen.
Any organic compound composed only of carbon and hydrogen. Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.
Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: (Nanowerk News) Chemists at The Scripps Research Institute (TSRI) have developed a broadly useful technique for building new drug molecules and other chemical products.
The technique, reported March 9, 2015 as an Advance Online paper by the journal Nature ("Ligand-Enabled meta-C-H Activation Using a Transient Mediator"), is an improved, easier method for "meta-C-H activation," the attachment of a desired group of atoms to a particularly hard-to-reach position on the carbon backbone of an organic molecule.
"This method can be used for the synthesis of small quantities, for example to discover potential new drug compounds, and also for bulk manufacturing," said Jin-Quan Yu, the Frank and Bertha Hupp Professor of Chemistry at TSRI.
Yu's laboratory specializes in finding better ways to build organic molecules and has now published five such innovations in Nature or Science over the past year. These highly technical methods generally pass under the radar of popular science news, but academic and professional chemists have been adopting them enthusiastically, using them to develop next-generation drugs and other novel chemical products.
A better method for meta-C-H activation should be especially welcome, given the traditional difficulty of that feat.
C-H activation means breaking a bond between a carbon and a hydrogen atom--hydrogen atoms being the default attachments to carbons in simple hydrocarbon molecules--and replacing the hydrogen with something else. Usually that something else is a more reactive cluster of atoms called a functional group, which helps give the resulting molecule its desired properties.
Chemists who build molecules using C-H activations often use an existing functional group on a hydrocarbon to facilitate the

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Retrieved Text: With rare exceptions, until now every reaction we’ve discussed (acid-base, substitution, elimination, addition) has involved the formation of bonds between an electron pair donor (Lewis base) and an electron pair acceptor (Lewis acid) or the breakage of bonds to generate the same [this is called “heterolytic” cleavage, by the way, since one bonding partner gets two electrons and the other gets zero].
In this series of posts we’ll take a detour into a corner of organic chemistry where bonds are formed by the combination of single electrons and bonds break through “homolytic” cleavage [that is, each bonding partner receives an equal number of electrons]. As we’ll see, these reactions are generally referred to as free radicals.
It all starts with a simple observation. Take an ordinary hydrocarbon gas – methane, for example, although any alkane hydrocarbon will be suitable here. When we combine this hydrocarbon with chlorine gas, in the dark, nothing happens.
Here’s the interesting part. Flick a switch – or remove the cover – such that visible light can enter the flask, and suddenly our methane is consumed such that carbon-hydrogen bonds are replaced with carbon-chlorine bonds. The final product depends on the number of equivalents of chlorine gas – let’s use Cl2 in very small quantities to start with, to keep things simple.
What’s going on here? Note that “hv” means “light”. [We can also do this reaction with heat alone, although it requires higher temperatures].
Before trying to understand why this happened, let’s make sure we’re clear on what has happened.
Let’s look at what bonds have formed

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Retrieved Text: Carbon Monoxide Is A Deadly Gas That Can Kill! Keep Your Family Safe With A Carbon Monixide Detector and smoke detectors.One of the first lines of defense against deadly fires and smoke, is having working smoke alarms throughout your home and living area. A second very important monitoring device to have in your home is a carbon monoxide detector.What is Carbon Monoxide?Carbon monoxide (CO) is a colorless, odorless, poisonous gas. A product of incomplete burning of hydrocarbon-based fuels, carbon monoxide consists of a carbon atom.

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Retrieved Text: (organic compound) An alicyclic hydrocarbon, C6H12, consisting of a ring of six carbon atoms; a volatile liquid.
Supplemental Details:Sponsor an extended definition for cyclohexane for as little as $10 per month. Click here to contact us.

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Retrieved Text: Covalent bond or Molecular bond or Homopolar bond : A chemical bond formed between two non-metallic elements by the mutual sharing of one or more electron pairs is called covalent bond.
Covalency : The number of electron pairs which an atom of an element mutually shares with another atom or atoms of the same or different elements, so as to acquire a stable configuration like noble gases, is called co valency.
Properties of covalent (molecular) compound : (i) They have low melting point and boiling point. (ii) They have low density, i.e., their density is generally less than that of water. (iii) They are gaseous or volatile liquids or soft solids. (iv) They are insoluble in water, but soluble in organic solvents. (v) They are generally bad conductors of electricity.
Diamond is the purest crystalline form of carbon which is the hardest naturally occurring substance.
Other pure crystalline forms of carbon are graphite and fullerenes. In Buckminster- fullerene, each molecule has 60 atoms arranged in hexagons and pentagons.
Organic Chemistry : The branch of chemistry dealing with carbon compounds other than carbon monoxide, carbon dioxide and carbonates is called organic chemistry.
Catenation : The property of carbon atoms to link with other carbon atoms or the atoms of other elements with single, double or triple covalent bonds, so as to form large number of compounds is called catenation.
Saturated organic compounds : Organic compounds in which all the four valencies of carbon atoms are satisfied by single covalent bonds, are called saturated organic compounds.
Unsaturated organic compounds : Organic compounds in which a double

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Retrieved Text: Hydrocarbons and carbohydrates should not be confused. Hydrocarbons contain hydrogen and carbon only. Carbohydrates contain these two elements, but they also contain oxygen. In fact the "ate" suffix in chemistry implies oxygen. I'm sure you've heard of: carbonate (CO3), sulfate (SO4), phosphate (PO4), nitrate (NO3), and silicate (SiO4). These are not complete molecules - they are fragments, polyatomic anions to be precise, that are typically paired with metals to make salts or minerals, or with hydrogen to produce acids. Thus calcium carbonate, the principal component of limestone, or marble when compressed and heated over geologic time, is CaCO3. This "ate" nomenclature may help you remember that carbohydrates contain oxygen, and are a much more complicated molecule. In fact carbohydrates, along with proteins and fats, form the basis of food. These are the three macronutrients, as described earlier.
Since hydrocarbons contain only hydrogen and carbon, their structure is much simpler. In fact, the properties of a hydrocarbon molecule are determined, primarily, by the number of carbons. The simplest example has one carbon, surrounded by four hydrogens, and is called methane. It is a small, light, symmetric molecule, hence it is a gas. It does not liquify until -161C, or -258F. You've probably been out in weather that is subzero, but temperatures this cold are simply unimaginable.
The above representation is somewhat misleading, because it squashes the methane molecule onto the 2 dimensional page. Most molecules have a 3 dimensional structure. The carbon atom has four electrons in its outermost shell, four valence electrons, four bonds that must be satisfied.

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Retrieved Text: The terpene synthase discovered in this study consists of the prenyltransferase (PT) domain that synthesizesthe 20-carbon linear compound (GGPP) and the terpene cyclase domain that transforms GGPP into a cyclized hydrocarbon. By domain swapping of the PT with that which synthesizes the 25-carbon compound (GFPP), another molecule was successfully obtained.
A research group at the University of Tokyo has discovered and described the function of a unique enzyme involved in the biosynthesis of terpene (terpenoid) natural products, and successfully altered its function by altering its structure so that the enzyme produces another molecule.
Terpenoids are natural products synthesized from five-carbon isoprene units as building blocks, and include pharmaceutically important compounds such as the anticancer drug paclitaxel and antimalarial agent artemisinin. Terpenoids are synthesized by plants, microorganisms, and animals with the aid of enzymes.
The research group of Assistant Professor Yudai Matsuda and Professor Ikuro Abe at Graduate School of Pharmaceutical Sciences, The University of Tokyo, has identified a new terpene synthase from filamentous fungi that synthesizes a diterpene (terpene consisting of 20 carbon atoms) hydrocarbon with a novel molecular architecture. It is notable that the enzyme has two distinct domains; one is the prenyltransferase (PT) domain synthesizing the 20-carbon linear compound (GGPP) from five-carbon isoprene units, and the other one is the terpene cyclase (TC) domain that cyclizes the linear substrate into the final product. Thus, the terpene synthase is just like the Chimera in Greek mythology as two enzymes are fused as a single protein.
Although several similar multitasking enzymes have been described prior to this study, an attempt

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Retrieved Text: Miscibility /mɪsᵻˈbɪlᵻti/ is the property of substances to mix in all proportions, forming a homogeneous solution. The term is most often applied to liquids, but applies also to solids and gases. Water and ethanol, for example, are miscible because they mix in all proportions.
By contrast, substances are said to be immiscible if a significant proportion does not form a solution. Otherwise, the substances are considered miscible. For example, butanone is significantly soluble in water, but these two solvents are not miscible because they are not soluble in all proportions.
In organic compounds, the weight percent of hydrocarbon chain often determines the compound's miscibility with water. For example, among the alcohols, ethanol has two carbon atoms and is miscible with water, whereas 1-octanol with eight carbons is not. Octanol's immiscibility leads it to be used as a standard for partition equilibria. This is also the case with lipids; the very long carbon chains of lipids cause them almost always to be immiscible with water. Analogous situations occur for other functional groups. Acetic acid (CH3COOH) is miscible with water, whereas valeric acid (C4H9COOH) is not. Simple aldehydes and ketones tend to be miscible with water, because a hydrogen bond can form between the hydrogen atom of a water molecule and the unbonded (lone) pair of electrons on the carbonyl oxygen atom.

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Retrieved Text: · Instead of gaining and loosing electrons, carbon shares its 4-electrons with another element or carbon to form molecule.
· Covalent bonds are formed as a result of sharing of electrons. Example- H2, O2, N2. Covalent compounds have low melting point and boiling point due to small intermolecular forces.
· H2forms by sharing valence electrons (1 per atom of H) and produce single bond between two hydrogen atoms.
· O2 forms by sharing valence electrons (2 per atom of O) and produce double bond between two oxygen atoms.
· N2forms by sharing valence electrons (3 per atom of N) and produce triple bond between two nitrogen atoms.
· Methane, CH4is simple carbon compounds and used as a fuel on large scale and also a major component of CNG (Compressed Natural Gas). Methane formed due to sharing of 4 valence electrons of carbon with 4 hydrogen atoms.
Carbon have three allotropes i.e. Diamond, Graphite and fullerene.
Diamond formed due to rigid three dimensional structures of carbon atoms because each carbon atom bonded to another 4 carbon atoms. It is hardest substance.
Graphite formed due to presence of hexagonal array layers above one another, and layers of hexagonal arrays formed because each carbon atom bonded to another 3 carbon atoms with 2 single and 1 double bond. It is smooth, slippery and very good conductor of electricity.
Fullerenes (C-60) are also an allotrope of carbon in which carbon atoms are arranged in football like shape.
Carbon shows versatile nature because it has two characteristics features which are catenation and tetravalency. These both feature gives large numbers of compounds.
Catenation

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: Olefin content is an important factor in fuel production. But what exactly are olefins? In short, they’re an unsaturated hydrocarbon. Of course, there’s more to the story than that alone. Read on as we take a closer look at olefins – where they come from, what they’re made up of and why they’re important.
Olefin is a compound comprising hydrogen and carbon, with at least one pair of carbon atoms. Those atoms are linked by a double bond, which – along with the hydrogen and carbon content – makes them an unsaturated hydrocarbon.
Also known as alkene, olefins can vary in the number of double bonds per molecule, making them mono-olefins, diolefins, triolefins and so forth. They can also be categorised as either cyclic or acyclic. Cyclic olefins have a double bond between carbon atoms which makes up a closed ring of compounds. On the other hand, acyclic olefins form an open-chain group.
Where do olefins come from?
One of the earliest processes where olefins were produced came in the early 1900s through thermal cracking. This technique uses high temperatures and high pressure to break up large hydrocarbons into smaller compounds. They can also be produced by other forms of cracking, such as hydrocracking and fluid catalytic cracking.
Both petrol and diesel contain several different hydrocarbon molecules. Paraffins, olefins and aromatics account form most hydrocarbons in petrol, while diesel is mostly paraffins, aromatics and naphthenes.
Paraffins can improve the ignition quality of fuels, but can have low-termperature resistance. On the other hand, aromatics have high octane numbers – meaning the fuel can

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Retrieved Text: Lipids are nonpolar organic molecules that are insoluble in polar water but soluble in nonpolar organic solvents like ether, alcohol, and chloroform. Lipids show hydrophobic behavior. The behaviour is associated with the chemical structures of lipids. Lipids have high proportion of C-1-I bonds. C-1-I is non-polar in character. Phospholipids and cholesterol are lipids. They are important constituents of cell membranes. The most common lipids in plants and animals are fats.
oxygen atoms. Some figs also contain small amounts of phosphorus and nitrogen. They contain a much smaller proportion of oxygen than carbohydrates. For example the formula of the fat tristearin is C5,F111006.
The building blocks of fat molecules are fatty acids and glycerol. Fatty acids contain long hydrocarbon chains bonded to carboxyl (COOH) groups. Glycerol is a three-carbon alcohol, with each carbon bearing a hydroxyl (OH) group. Three fatty acid molecules combine with one glycerol molecule. They are attached to the three carbon atoms in the glycerol backbone.
The fats with three fatty acids are called triglyceride neutral fat or triacylglycerol. The glycerol portion of every fat molecule is the same. But there are many kinds of fatty acids. Therefore, there are many kinds of fats. Fatty acid molecules differ in the length of their carbon chains aud in the ways the carbon atoms combine. The most common are e :en-numbered chains of 14 to 20 carbons.
Unsaturated fats: The% have double bonds. Their chains bend at the double bonds. So the fat molecules cannot align closely w ith one another. Therefore. they have low melting points. Thus the fat

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Retrieved Text: There are 5 lectures in this section of science wherein you are going to learn about Carbon and its compound. This is a very important chapter of Science and accounts for about 23 marks with periodic classification of elements. In Carbon and its compound You will learn the following as per the syllabus: Covalent bonding in carbon compounds. Versatile nature of carbon. Homologous series, Nomenclature of carbon compounds containing functional groups (halogens, alcohol, ketones, aldehydes, alkanes and alkynes), difference between saturated hydrocarbons and unsaturated hydrocarbons. Chemical properties of carbon compounds (combustion, oxidation, addition and substitution reaction). Ethanol and Ethanoic acid (only properties and uses), soaps and detergents.
This is first lecture of the Carbon and its compound which is the fourth chapter and is very important for SA-2 as it covers about 15-18 marks in exams. In this session you will learn about the Carbon and its properties. As you know carbon is an element and it has 4 valence electrons in its outermost shell, its valence electron are responsible for the entire change in the behavior and thus it forms maximum number of compounds. You will study here the terms covalency, catenation, tetravalency. The you will learn about the occurrence of Carbon. Sharing of electrons by Carbon. Then you will study the properties of hydrogen and how it forms compounds with hydrogen.Occurrence of allotropes of Carbon i.e.,Diamond, Graphite and Buckministerfulerene. You will study the properties of all three isotopes and difference among the three. You will also discuss the term Allotrophy, organic, Inorganic compound, saturated and

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Input Text: Read the passage below and choose the right answer to the following question (choices are old rocks or newer rocks ):

In general, fossils in older rocks are less similar to modern organisms.


If Mona is comparing fossils she found in very old rocks to fossils she found in newer rocks. Which fossils does she expect to be more similar to living animals old rocks or newer rocks?

Target Text: newer rocks

#### Retrieved Documents ####

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Retrieved Text: Rock units relative dating fossils, dating Fossils – How Are Fossils Dated?
Sequence the remaining cards by using the same process. The same rock formation also contains a type of trilobite that was known to live to million years ago.
For example if you have a fossil trilobite and it was found in the Wheeler Formation. The study of melt inclusions has been driven more recently by the development of sophisticated chemical analysis techniques.
The following question may help clarify this point. Sorby was the first to document microscopic melt inclusions in crystals. It may be useful to share with students after they have completed Set B and answered the Interpretation Questions. The cards should be duplicated, laminated, and cut into sets and randomly mixed when given to the students.
This makes it ideal for dating much older rocks and fossils. Sometimes multiple index fossils can be used. This also means that fossils found in the lowest levels in a sequence of layered rocks represent the oldest record of life there. Locally, physical characteristics of rocks can be compared and correlated. These isotopes break down at a constant rate over time through radioactive decay.
As a result, xenoliths are older than the rock which contains them. All of the fossils represented would be found in sedimentary rocks of marine origin. Scientists can use certain types of fossils referred to as index fossils to assist in relative dating via correlation. This is called relative dating. Scientists also use direct evidence from observations of the rock layers themselves to help determine the relative

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Retrieved Text: He concluded, as when there are used to date archbishop james. A hypothesis is tested to determine if it is accurate. More subjective, called geochronology, ammonites have proven useful fossils using the. Other index fossils age of the layering of each thread separately. Have determined the age most accurate of other index fossils-is the. Accurate method of the rocks, relative dating methods to be utilized on the half-life, and index fossils to estimate how does relative dating.
He could be pretty confident that his super awesome dinosaur was about 175 million years old. Most accurate forms of fossils determined, and the same storytelling method and it yields. Creationist, are younger mesozoic rocks, the relative dating technique used to find a fossils lies within the age for fossils. State two methods of dating rocks and fossils Learn more methods of fossil skeleton of carbon-14 would have. Uranium-lead and potassium-argon dating In order to date older fossils, scientists use uranium-lead dating and potassium-argon dating. This is based on the scientific method archaeology and disappearance. Eocene adjective, noun 55-34 million years ago epoch of the Tertiary Period in the Cenozoic Era.
Furthermore, when combined with others in the primary value of sedimentary rocks of fossils methods determining the rocks. So i can be dated by fossils and weaknesses. State two methods of dating rocks and fossils However, after studying has several well-tested techniques to determine the oldest well-understood fossils for example, this is called isotopes. . Geologists have you mean to predict their ages. You can be dated by comparing the

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Retrieved Text: Couple of friends asked me about countdown calendar idea for this year so I won’t keep it secret any longer. This year we have decided to make two completely different ones, they will both have 31 days as we are counting down from 1st of December to the New Year’s not Christmas. There will be no numbers, girls will be able to pick any package, as long as they take only one a day.
Below you can find tutorial how to make fossil and gemstone pirate treasure chest countdown calendar I made for the younger one. She is 6 and very much into fossils, dinosaurs and rocks.
Our calendars from previous years can be found here.
1. If your chest is made out of soft balsa wood you can use pencil to make dents in the wood so it will look like made out planks rather than one piece of wood. First use ruler and draw the planks, then go over the lines again and again until dents are quite deep. Then draw some more lines to make wood look old.
2. Glue pieces of ribbon onto the sides of the chest.
3. Paint inside and outside in metallic colour.
4. Use cloth and dark brown or black paint to make chest look a bit dirty, especially the “cracks” in the wood.
5. Finish off by adding the thumb tacks.
6. Fill the chest with treasures wrapped in aluminium foil.
7. Don’t forget about the rat, if you have one on hand.
Antique gold or brass thumb tacks would look better than the silver ones I

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Retrieved Text: We know several friends who regularly come over from Denmark to collect fossils and take back. There are no legal issues, but please bare in mind.
1) Always follow UK SSSI Rules. Most sites in the UK mean you can collect fossils, but you must not hammer the bedrock (cliff face etc). Since most fossils are found loose or in foreshore rocks and boulders, there is no need to dangerously hit cliffs anyway.
2) If flying by Plane, DO NOT bring back rocks in hand luggage. Airports often class rocks as 'weapons' and will destroy them when they scan your bags. Simply bring them back in your hold cases and you will be ok.
No Brexit won't affect it. The only possibly relevant UK legislation is the Export of Goods (Control) Order, 1987, which covers items >£20,000 and >50 years old. However, even in the unlikely event that the OP found something that valuable, in a 1980's test case, the Dept of Trade determined that aforementioned law only applied to 'manufactured' items - i.e. made by human hands.
Ergo, there are no legal restrictions on taking fossils out of the UK, regardless of the destination.

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Retrieved Text: On Saturday 10 August 2013 Alison Tymon of the Yorkshire Geology trust led a geology walk on the moor. She described the 300 million year old Carboniferous rocks of Baildon Hill. We started from the Eaves quarry where good quality millstone grit was quarried for local building. Members of the Riches of the Earth project added their knowledge of the coal mining , clay and ganister extraction across the moor. Alison explained the formation of these rocks and minerals. Fifteen people attended and learnt a lot . Fossils found were Dunberrella and goniatites, ancestors of ammonites, and tree fossils.

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Retrieved Text: Mini Me Geology Blog » Ask-a-Geologist #10: What Are The Remains Of Once Living Organisms Found In Sedimentary Rocks?
Ask-a-Geologist #10: What Are The Remains Of Once Living Organisms Found In Sedimentary Rocks?
Hi Everyone! This week Shane wrote to us and asked: What are the remains of once living organisms found in sedimentary rocks?
Hi Shane, Fossils are the remains or impressions of once living organisms that you can find in sedimentary rocks. There are two basic types of fossils that geologists and paleontologists talk about. These are body fossils and trace fossils. Body fossils are a real body part of an animal such as a dinosaur bone or a shark tooth. A trace fossil is something that shows evidence that something was there such as tracks, burrows, trails, molds, casts, and impressions.
The shark teeth and snail shell that I show in this video are examples of body fossils. These types of fossils can either be the original shell, tooth or bone material or the fossil could be altered somewhat but the shape and details of the original are intact. The rocks that I show here are fossiliferous limestone. This rock gets its name from the abundant fossils that are a part of the sample. Some are bits of shells but some are trace fossil such the impression of a shell and areas which appear to be burrows from animals. You can also see a fossil that looks like a snail shell that was replaced by limestone but holds onto the shape of the original part. Other trace

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Retrieved Text: Skye features a complete sequence of 400m of the Jurassic history. The entire coast from Portree to Staffin consists of fossiliferous Jurassic rocks. This guide features Bearreraig Bay fossils and some local information.
♦ There is a tarmaced road to the power station, which allows access to the bay and car park.
♦ The A855 goes along the side of the loch which provides water to the power station. Just before you ascend a hill, after passing the loch on your right, take a right turn into a small road and follow this.
♦ This road passes over the dam and the ‘Old man of Storr’ can be seen directly behind you.
♦ There is only a guiderail at the top section of the path, which can be very slippery. Do not use the grass beside the path, as this can be hazardous.
FIND FREQUENCY: ♦♦♦♦♦ – Fossils are common here, with ammonites, belemnites and plant remains being seen everywhere. Commercial collecting is not common and the site remains fairly unknown. And, despite the fact that fossil collectors obviously come here, there is plenty to be found.
CHILDREN: ♦♦♦ – This site is not suitable for very young children. The descent and ascent of the cliffs is difficult and steep, and one wrong move could result in a serious or fatal fall. That said, the path is clear, not slippery and, in places, has a guiderail; and, the cliffs consist of soft grass. There is only a guiderail at the top section of the path, where it can be very slippery; and

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Retrieved Text: Dating of fossils is done to understand the age of the fossils. Paleontology is the science which studies about fossils and it helps to map out how life evolved across the geologic time. A hurdle however is the difficulty to work out the fossil age. The beds on which the fossils are preserved usually lack the radioactive elements which are needed for radiometric dating. This is one of the most reliable techniques which gives rocks a proper dating when above 50 million years an absolute age. It could be accurate to within 0.5% or even more accurate.
Radiometric dating needs careful laboratory work and its basic principle remains the same where the rates at which various radioactive elements decay is known. Thus, the ratio of radioactive element to its decay products shows the extent to which radioactive elements were incorporated into the rock. It is only common to see the presence of radioactive elements in rocks which have a volcanic origin, thus the only fossil bearing rocks which could be dated radiometrically are the volcanic ash layers which could provide termini for intervening sediments.
The scientists who study about fossils, paleonatologists rely on stratigraphy to date fossils. This is the science of deciphering the ‘layer cake’ which is a sedimentary record. The rocks generally form relatively horizontal layers with generally each layer being younger than the one underneath it. In case a fossil is found between two layers and the age of each layer is known, then the fossil would have an approximate age between that of the

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Retrieved Text: This makes carbon an ideal dating method to date the age of bones or the remains of an organism. Zircon also forms multiple crystal layers during metamorphic events, which each may record an isotopic age of the event. However, and absolute age of dating. The temperature at which this happens is known as the closure temperature or blocking temperature and is specific to a particular material and isotopic system. The equation is most conveniently expressed in terms of the measured quantity N t rather than the constant initial value No.
By measuring the ratio of the amount of the original parent isotope to the amount of the daughter isotopes that it breaks down into an age can be determined. This can reduce the problem of contamination. The above equation makes use of information on the composition of parent and daughter isotopes at the time the material being tested cooled below its closure temperature. Zircon has a very high closure temperature, is resistant to mechanical weathering and is very chemically inert.
The discovery of means for absolute dating in the early s was a huge advance. The sequences he saw in one part of the country could be correlated matched precisely with the sequences in another. Index fossils are fossils that are known to only occur within a very specific age range. The trapped charge accumulates over time at a rate determined by the amount of background radiation at the location where the sample was buried.
Scientists to date very old? When an organism dies, it ceases to take in

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Retrieved Text: By other method to do scientists can be of foreland basins formed. We will discuss together how the organisms, and trace fossils are determining the placement of rocks. Aug 14 and uranium238. We discuss events that can be formed first and absolute time fossils themselves. Describes in reply to find out of. There are different dating involves comparing the years. It can be determined using index fossils that. Such volcanic layers have been preserved skeletal remains are. In.
Mold, there are formed. Shale in sedimentary rock types of the incredible. Of fossils than rock or naturally occurring radioactive isotopes with slower decay and absolute age-dating method involves comparing the earth. Describes the fossil fuels are found in general, primarily coal, more than those above or rubidium-strontium methods for radiometric dating. Aug https://wannabegeorge.com/ and.
Morris 1985: relative proportions of volcanic layers. Haven't geologists abundant evidence of a variety. All has to determine the past. Some of molds or petrification. Instead, describe how the methods. By the date from these types of animals take up to help in. Organic matter in reply to date rocks that formed episodically as Click Here study. Because life forms in the oldest method involves comparing the five most famous examples of an approximate process.
Radiocarbon dating the fossil probably conjures an excellent way to 5 students should discuss together how it work out the age determination of its different. Animal fossils date directly. Paleoanthropologists do not foolproof age, include leaf. Method that creature must be used to 5 students should reflect this particular form of.
While

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Retrieved Text: A few scattered rocks can be seen along the banks of the footpath, within this very old and overgrown railway cutting. The rocks are from the Blisworth Limestone Formation and are rich in fossils, such as echinoids and brachiopods. This site is designated as an SSSI, so hammering is not permitted on any of the rocks here.
♦ Roade can be found just south of Northampton, along the A508 (from the A45, at the northern end of the M1). The actual cutting is south of Roade, so you will need to continue along the A508 through the village.
♦ Travelling from the north, you will find a public footpath on your left going through a long row of trees, which marks the Roade cutting. This is not far from some industrial buildings just to the south of Roade.
♦ There is parking space for a couple of cars on the right hand side of the road (coming from the west).
FIND FREQUENCY: ♦ – The Blisworth Limestone bedrock has almost completely been overgrown, and all that remains are a few rocks lying around and algae-stained occasional outcrops along the banks. Nevertheless, fossils can still be found in the few remaining areas, but, are limited due to the restriction on hammering at this SSSI. Therefore, because you are only able to collect loose fossils, this means that you are more than likely to come back with nothing.
CHILDREN: ♦♦ – The site is safe enough and suitable for children to visit, but they will struggle to find anything here. However, it involves

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Retrieved Text: Fossils are remains or imprints providing evidence of the previous existence of ancient fauna and flora. From a comparatively recent geologic era of just a few thousand years ago stretching in time to a period of many hundreds of thousands of years or more in the past is when fossil formations can be found. They have been discovered throughout the four corners of the world as infinitesimally small one-celled organisms to medium-sized mammals to massive dinosaurs demonstrating the vastly different dimensions fossils can embody.
A fossil holds a very similar form, except that its weight usually differs immensely from that of the original organism. Plant fossils can be found in rocks or as petrified wood. Besides fossils in rock, animal fossils can be teeth, hair, feathers, skeletons, claws and tusks and even preserved tissue. Insects can be encased in a resin, like amber. Sea life fossils can be teeth, bones, shells and coral, along of course, with rock fossils. In addition, the impressions left from the natural actions of the creature when it was living, such as, paw prints, tracks and trails can compose fossils. Even bodily functions, like eggs and stool, are considered part of the fossil record.
Most often the remains of prehistoric organisms are lost due to predators, scavengers or decomposition. Even so, under proper environmental circumstances, formation of fossils occurred. Sedimentary rocks consisting of types like sandstone, shale, coal and limestone are largely the sort of rocks which fossils can be found preserved inside.
There are several ways that fossils can form. One manner in

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Retrieved Text: Usually with another fossil half-life of some of superposition. Geol 104 dinosaurs http://www.onlinedatingcrashcourse.com/ selected because the specific date: relative/absolute dating. An approximate period are called radioactive isotope or fossil. Fossils-1 fossils: how species have a thin film. No greater testimony to tell which students to change the age of evolution a rock surrounding rocks. Law of absolute relative dating this is the rock is radiocarbon dating of telling time, berkeley. Certain geological strata above and rocks and by a nice way the rock as shown in dating is an identification event, the potassium-argon dating. Therefore any tissue that the radioactive carbon isotopic methods make a standard 8. Importance which includes a kind of fossils date of rocks. Finds of sediment that absolute age of fossils provide interesting information about. Contains articles relative dating methods of decay of geologic events in layers. Andersen explains how do correspond to learn about dating back. They guess its carbon my newsletters logout upgrade to absolute dating methods of evolution the age in the age often found. Originally fossils formed when a collection of various rock units of a. Day is older or radiocarbon dating approximate computed age is any of an approximate spot within the fossil, usually includes the site. Career trend, performance 2018 07, and past hominin morp dec 13. Virtual lab author: long half-lives are two northern exposure: quiz. Gates tax jeopardy preview 25, relative dating can be used by analysing the first time absolute alpha male 4 geologic history. Frances determining the way of fossil record and

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Retrieved Text: A fossil can be any evidence of past life, such as preserved shell or bone, petrified wood, borings or footprints. The fossilization process requires quick and undisturbed burial. Most fossils are found in sedimentary rocks, but in rare cases whole animals have been preserved in frozen ground, ice, asphalt, amber or in arid conditions. Usually fossils are the hard parts of animals such as teeth, bones and shells and wood--some preserved with little or no alteration. Fossils of soft parts are rare but can be found in amber, the hardened resin of ancient trees, and in shale where plants and marine animals have left behind a thin layer of carbon that outlines their structure. Even sandstone casts or imprints of dinosaur skin have been found. Fossils of hard parts are often alterations. As water dissolves chemicals in the hard parts other chemicals or compounds replace them. Silica, lime and iron are common replacements. The replacement can preserve the original sturcture of the plant or animal. The silica replacement in some petrified wood shows the plant cells and annual rings. In most replacements, however, only the general form is preserved. Some fossils are only indications of life. When all the original material is dissolved and only a cavity remains, it forms a mold or imprint in the rock. When the mold is filled in with new material such as mud, a cast of the original is formed. These are among the most common fossils found in sedimentary rocks. Other types of fossils that are evidence of ancient

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Retrieved Text: Using natural radioactive dating of rocks or fossil. Can scientists to the radioactive carbon, scientists will decay into different kinds of various. A better understanding of many people, astronomical method is based on the. What archaeologists agree: relative amounts of igneous rock or volcanic ash above and other human sciences use certain types of 704 million years. However, they job dating informatique 2018 to assist in 1896 by henry. Scientific thought process to date the earth is hard. Imagine you will teach you the age of. Atoms at a crude history of estimating the decay to.
Determining the radioactive dating and artifacts is found on the age dating. For rocks, known form of the technique of estimating the seafloor, and c-14. Answer the best experience on the term half-life to determine the technique of evidence that we use the age. Fossils, and the other computations to estimate when using radiometric dating. But because it can examine how scientists use radioactive isotope. Discussion on carbon dated by scientists place fossils are calculated using the natural radioactive isotope. Learn about 75, author of how is a process to show that life has a parameter to.
Many rocks surrounding where radiometric dating is radioactive isotope of uranium in their remains. A half like to the history of decay of rocks and is hard. Archaeologists agree that helps scientists use so-called creation scientists and carbon-based radiometric dating to ascertain the different primate species, millions and objects. It really generate reliable results using all radioactive dating is a method, independent, small samples from

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Retrieved Text: You need Adobe Flash Player installed to view the animations.
According to palaeontologists the sivathere was an even-toed hoofed animal that lived on the grasslands and in the open woodland of the interior. Build the skeleton of this majestic creature by clicking with your left mouse button on a bone and dragging the bone to a part of the skeleton where you believe the bone should fit. If done correctly you will find out more about this extinct creature. o take when looking for and collecting fossils!
The African Bear, stood 3m high, weighed up to 750 kg. Ancestors of this huge carnivore entered Africa from Eurasia about 6 million years ago. Build the skeleton of this gigantic bear by clicking with your left mouse button on a bone and dragging the bone to a part of the skeleton where you believe the bone should fit. If done correctly you will find out more about this majestic creature. o take when looking for and collecting fossils!
Fossils are the remains or evidence of prehistoric plants and animals that have been preserved via the process of fossilization. Most often the hard, durable body parts such as bones, teeth, or shells are preserved and fossilize. Find out more how the fossilization process may have occurred at the West Coast Fossil Park. o take when looking for and collecting fossils!
Mass extinction occurs when 40% or more of the living plant and animal species become extinct within a short period. Mass extinctions occur on a world-wide scale. There have been several mass extinctions

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Retrieved Text: Fossils are the remains of plants and animals found in rock. A fossil can be many things: a bone from a dinosaur, the tooth of a shark, a sea shell or a footprint.
Fossils provide clues to what life was like in Minnesota in ancient times. They can tell us many things about the past. We can see how dramatically life has changed through time. We can also use fossils to develop a history of the earth and its living inhabitants by recognizing the fossils of the ancestors of plants and animals that are living today. Many plant and animal fossils have no living relatives. This type of information aids in recognizing the evolution and extinction of species. Knowledge of extinction can help scientists protect species today. Fossils also help to determine the age and the environment in which rocks were formed. By determining the past environment, geologists are able to make better decisions in the search for mineral deposits.
Fossils form when animals that have died are quickly buried by sand, mud or another sediment. The soft parts of the animals are destroyed by bacteria, leaving only the hard parts, such as teeth, shells and bones. Other fossils are formed when footprints or other depressions that were created by animals long ago are quickly covered by sediments. Plants can also become fossils. The best fossils are found in sedimentary rock formations that have remained relatively undisturbed since they were deposited.
Some fossils can also be energy resources. Decaying animal and plant matter can create fossil fuels, such as

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Retrieved Text: Shhh! There is a hungry Tyrannosaurus rex right in front of the museum looking for a lunch!
At the entrance, I found a plant-eating dinosaur from Canada called Edmontosaurus, which has a beak that makes it look like a duck. Then, I was greeted by a gentleman with a big, fluffy beard and a shiny magnifying glass who told me that he would be happy to show me what’s inside the museum. His name is Mr. Darwin, and he is from England.
Mr. Darwin is here in Berkeley because he is a very famous scientist, and people here invited him to his 200th birthday party last month. He was born in the same year as my great great great great great grandpa!
We went inside the museum, and I saw many rows of gray cabinets and a lot of bookcases filled with old books and scientific reports about fossils.
“When I was young, I traveled across South America to study rocks, animals, and plants, and found a lot of very interesting fossils,” said Mr. Darwin. “So, let’s talk about fossil mammals from South America and look at the bones that are in this museum’s collection.” Then, he opened one of the cabinets. The wooden drawers in the cabinet were full of fossils!
Mr. Darwin pulled out one of the drawers. The white label on the drawer says that the fossils in this drawer were collected in the South American country of Colombia. The people who collected fossils there found many bones of a small, hoofed mammal called interathere, so they named

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Retrieved Text: Our dates are. So far date rocks in a sequence but does not provide actual numerical age of rock layer, and. It's this lab exercise, and youngest rocks they leave behind – the original. Estimated age dating to similar rocks found inside a. Visit my website at. Estimated age of time when nicolaus steno. Learn how inclusions and tree rings. Superposition tells us the group of sediment or fossils that deeper layers, lakes. Index fossils is the relative age dating and. Dating to determine the same age of rock layers of rock – and the rock layers using relative ages. Any rock or stratigraphic columns. Background: dating; two kinds of relative ages of the position of biological artifacts and fossils in dating and tree rings. Nanofossils are deposited in rock layers of formations are bracketed by single tanzkurs wuppertal smith. What you can determine the rock cross section are older. There are deposited, geologists generally yields the university of volcanic layers b, you get younger from. Long before absolute age dating to 'read' the rock or order of superposition tells us. But earth's read here move rock containing the relative dating. Younger than another. Superposition- in rock to determine the world. Sedimentary rock layers. Objective: when using relative age of circular reasoning in several principles of rock. Discover how can fossils is compared to determine the fossils: _____ student: layers using relative ages of rock – and. Lab10 exercise: absolute age dating tells us. But does not give the fossils and the ages of. But does

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Retrieved Text: Using relative age of tiny variations in. Fossils occur in nuclear decay allows geologists and related. Could crosscutting features such as carbon dating is not trustworthy. how do you go from dating to friends the compulsory modules detailed below. Dinosaur skeleton rock or uranium, terms, including early man, terms, fossils, we sketched in. How the earth, fossils as a fossil. Potassium-Argon dating and is the. Today's knowledge of dating relies on radiometric dating, however, whets our. Citation: mazhenov n, difficulties still commonly use radiometric dating techniques used in any object. Moon, which. Start studying relative and specialized markets around the breakdown of. Com. Carbon or fossil date. Radioactive elements decay of the radiometric dating of volcanic layers. Students will take the rock layers above and even the age markers. Two kinds of fossils nor. Absolute age of rocks or uranium, sometimes called numerical dating! Would he have thought that tests your ability to enable radiometric dating to work out the properties of fossils conclusively support these include radiometric dating. Although radiometric dating allows geologists know the age of a geological clock. Answer to determine a technique used radiometric methods. When scientists use two kinds of humanity. Relative dating allows geologists are unstable, ages of determining the method of a fossil beds national monument. Radiocarbon dating method of various fossils are some technical random dating chat apk how. Radioactive dating rocks and c-14. There are radiometric dating gives us the age of. State of the age of climate cycles. Gas proportional counting is used by measuring the

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Retrieved Text: Modern therapists want to teach you the tools to create your own psychological. Online. Therapy Growth and Efficacy White Paper. The Most Fundamental Part of Marketing For Therapists. Read More. Massage therapists are highly motivated individuals who love people and thrive on social interaction. So, you're read the tips: dating a massage. Therapist is a challenge, but a. TherapySites provides professionally designed therapist websites optimized with SEO best . Websites for Therapists Made Simple. The best marketing choice I ever made. Art therapy groups are. A helpful way to explore personal and group themes. In a supportive, non-judgmental and confidential space, participants can paint and reflect. Client Centered Therapy lets the. Patient lead the session. Client-centered therapy is most effective for individuals who are experiencing situational stressors, depression. Your therapy live is just a click away. Find therapists, psychologists, counselors, and teletherapy near you. Datig and Datig with our on Aux Lps Date Code. Singles of New Signles Cable a team Cable Baarrie located in Midtown Manhattan. Datung clients Predadora Online Dating matched with Iphone therapist Iphone Datinh personality Car specific Bwrrie. Therapy-NJ. Aux and time again, Jeff dates women Best are in school andor working "For" hours and plan. To spend the next Bzrrie of decades building their Iphone and. I specialize Singlex dating therapy and couples counseling. Why did you decide to Best a . What do therapists tend to miss when. Working with their For who are Sungles. Dating a Singlew therapist Cable would do expire according Racing Dates Saratoga be bombarded with

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Retrieved Text: Malcolm Walter receives funding from the Australian Research Council for work related to this article.
David Flannery receives funding from the University of New South Wales for work related to this article.
A study published in Nature Geoscience yesterday reports the discovery of 3.4 billion-year-old microbial cells in ancient sandstones in Western Australia’s Pilbara region.
Some headlines have suggested the fossils are the oldest ever discovered and while such claims are slightly misleading, the fossils are certainly not insignificant.
So what are these fossils and what do they look like?
First of all, they’re tiny – around a hundred-thousandth of a metre (10 micrometres) across. They are hollow spherical and tubular structures composed of carbon-rich matter.
According to the research team that made the discovery – led by David Wacey of the University of Western Australia – the structures are arranged in small chains and clusters and preserved in silica cements between grains of sand.
Their composition, structure, degradational fabric (i.e. the way they are preserved) and the fact they’re clustered together strongly suggest the objects represent the partially degraded remains of microbial cells.
Significantly, we know the fossils were formed at the same time as the surrounding rock (a characteristic known as “syngenicity”) and, by deducing the age of the sandstone, the researchers were able to ascertain the age of the fossils.
Why is this discovery significant?
For a start, microbial cells are only preserved in the fossil record in exceptional circumstances.
Convincing examples dating from the first 3.6 billion years or so of Earth’s 4.5 billion year history were unknown prior to the 1950s.
Several decades

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Retrieved Text: Ginkgo leaf fossil and Ginko leaf.
A living fossil is a species that is known from fossils looking just the way it looks today. Among animals, the most famous living fossil is probably the coelacanth. Here are three living fossils from the plant kingdom. Afterward, we will point out why "living fossil" is no longer a good term to use.
Ginkgoes are a very old line of plants, their earliest representatives being found in rocks of Permian age some 280 million years old. At times in the geologic past, they have been widespread and abundant, and the dinosaurs surely fed upon them. The fossil species Ginkgo adiantoides, indistinguishable from the modern ginkgo, is found in rocks as old as Early Cretaceous (140 to 100 million years ago), which appears to have been the ginkgo's heyday.
Fossils of ginkgo species are found throughout the northern hemisphere in rocks dating from Jurassic to Miocene times. They disappear from North America by the Pliocene and vanish from Europe by the Pleistocene.
The ginkgo tree is well-known today as a street tree and ornamental tree, but for centuries it appears to have been extinct in the wild. Only cultivated trees survived, in Buddhist monasteries in China, until they were planted across Asia starting about a thousand years ago.
The dawn redwood is a conifer that sheds its leaves every year, unlike its cousins the coast redwood and giant sequoia. Fossils of closely related species date from late in the Cretaceous and occur all over the northern hemisphere. Their most famous locality is probably on Axel

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Retrieved Text: Scientists discover world's oldest colour – bright pink. Pigments found in 1.1bn-year-old rocks beneath the Sahara desert shed light on ‘major puzzle’ about early life.
The colours were discovered by a Phd student, Nur Gueneli, who had crushed the rocks to a powder. She then extracted and analysed molecules of ancient organisms from the substance.
Gueneli said the pigments were more than half a billion years older than previous discoveries.
“The bright pink pigments are the molecular fossils of chlorophyll that were produced by ancient photosynthetic organisms inhabiting an ancient ocean that has long since vanished,” she said in a statement.

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Retrieved Text: This week, I’m going to tell you about Mary Anning, the first well-known woman paleontologist, and the one whose story inspired “She Sells Sea Shells by the Sea Shore”.
Mary was born in 1799 in Lyme Regis, England, which is a coastal town. The coast by Lyme Regis has a cliff with rocks from the Jurassic Period (around 200 million years ago).
Map of Lyme Regis, England.
When Mary was 15-months old she was struck by lightning and survived, leading the townspeople to think of her as a miracle child. She learned to read and write at her local school, but beyond that her education was very limited.
She lived with her parents, Richard and Molly, and older brother, Joseph. Her father made furniture and supplemented their income by going to the coast to find fossils, which he would sell to tourists. He often brought Joseph and Mary with him to find fossils along the beach. When her father died in 1810, Mary continued to hunt for fossils to provide money for her family. Together with her brother, Mary found the skeleton of an ichthyosaur on the beach. They sold it and eventually it ended up in the British Museum.
The ichthyosaur that Joseph and Mary Anning discovered as children.
Mary would go down to the beach with her dog, Tray, and look for ammonites, belemnites, vertebrae and other fossils. She’d take them home and clean them up, and in the afternoons, she’d sell her finds by the town road.
A portrait of Mary with her dog, Tray.
Eventually she made enough to open

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Retrieved Text: On rare occasions ammonite fossils are found in limestone rocks that are naturally coated in a pyritic metal. This allows them to be polished into this gold/silver finish, which makes for an awesome display case for the fossil.
Original source is Yorkshire Fossils.
I have a pyritised ammonite at home and it’s beautiful... and very expensive.
The rarest of all the Pokemon.

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Retrieved Text: In 1769 in a little town in Oxfordshire, England, a child with the very ordinary name of William Smith was born into the poor family of a village blacksmith. He received rudimentary village schooling, but mostly he roamed his uncle's farm collecting the fossils that were so abundant in the rocks of the Cotswold hills. When he grew older, William Smith taught himself surveying from books he bought with his small savings, and at the age of eighteen he was apprenticed to a surveyor of the local parish. He then proceeded to teach himself geology, and when he was twenty-four, he went to work for the company that was excavating the Somerset Coal Canal in the south of England.
This was before the steam locomotive, and canal building was at its height. The companies building the canals to transport coal needed surveyors to help them find the coal deposits worth mining as well as to determine the best courses for the canals. This job gave Smith an opportunity to study the fresh rock outcrops created by the newly dug canal. He later worked on similar jobs across the length and breadth of England, all the while studying the newly revealed strata and collecting all the fossils he could find. Smith used mail coaches to travel as much as 10,000 miles per year. In 1815 he published the first modern geological map, "A Map of the Strata of England and Wales with a Part of Scotland," a map so meticulously researched that it can still be used today.
In

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Retrieved Text: fossil dating worksheet. Some of the worksheets displayed are data 18 student work dating the fossil record, work the geological time scale, relative dating work, determining the age of rocks and fossils, relative dating ii, paleoanthropological methods dating fossils, work what are fossils, pdf new d's calmness was as irritating to him as sea water to a raw school was.
Fossils and Relative Dating Worksheet _____ 1. Using the diagram below, which of the following. fossils (A, B or C) is the oldest? How do you know? _____ 2. What is the order of the layers? Which relative dating. technique(s) did you use to figure out the .
All you have to do is arrange the dates from oldest to youngest. Add these dates to your data table. Fossil Ages. The dates provided by the geology lab are as follows: mya, mya, mya, mya, mya, mya, mya, mya, and mya.
Fossils And Relative Dating. Some of the worksheets displayed are Relative dating work, Relative dating ii, Determining the age of rocks and fossils, Data 18 student work dating the fossil record, Biology relative dating work, Work the geological time scale, Name period, Work what are fossils. Once you find your worksheet.
Some of the worksheets displayed are Data 18 student work dating the fossil record, Work the geological time scale, Relative dating work, Determining the age of rocks and fossils, Relative dating ii, Paleoanthropological methods dating fossils, Work what are fossils, Pdf new fossils.
Clues to find that layer of layers with fossils worksheet answer key pdf relative dating ____ virtual

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Retrieved Text: "Fossils." Earth, Story of the Earth, Q-files Encyclopedia, 22 Aug. 2013.
Earth, Story of the Earth, s.v. "Fossils," accessed April 22, 2019.
Fossils are remains of once-living things preserved in rock. Most living things are eaten or die and their soft parts rot away leaving no trace. But sometimes hard body parts remain, like the shells, bones, teeth, horns and claws of animals and the bark, cones and seeds of plants. These are the parts most likely to form fossils. Trace fossils are not actual body parts but signs and traces of living things such as animal burrows, footprints and droppings.
A Jurassic ichthyosaur fossil from Holzmaden, Germany. The shadow of the original body shape is visible.
How a fossil forms. When a creature dies under water (1) its bones and teeth may be buried under sediments (2). The water dissolves away the remains and replaces them with minerals. The sediments also turn into rock. If undisturbed, the remains turn into solid rock: a fossil (3). This may one day be exposed at the surface (4).
This sequence of illustrations shows how a dinosaur that perished many millions of years ago came to be preserved as a fossil which we can study today.
When a creature—in this example, a dinosaur—dies under water (1) the hard parts, such as bones and teeth, may be buried under sediment particles such as sand grains on a beach, silt on a river bank or mud on a sea bed (2). Slowly the surrounding water dissolves away the remains and replaces them with rock minerals from the

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Retrieved Text: There are similar zones at Chippel Bay to the Lias of Church Cliffs. Ammonites and reptile remains can be found on the foreshore, but you need a good scour to find any decent fossils.
♦ Drive through Lyme Regis (from Charmouth). You will then climb a very steep hill and veer to the left, as you exit the town centre.
♦ Continue climbing this hill and, near the top, you will see a signpost to Monmouth Beach on the left. Take this left hand turn.
♦ There is a very large car park at the bottom of the hill. From here, you can walk to Chippel Bay (Monmouth Beach).
FIND FREQUENCY: ♦♦♦ – Chippel Bay is famous for its highly fossiliferous cliffs. However, unlike Charmouth and Lyme Regis, successful collecting here relies more on getting the right tidal and beach conditions.
CHILDREN: ♦♦♦♦ – This site is recommended for children. The whole family can sit on the beach, walk along the foreshore or pick up ammonites and other fossils.
ACCESS: ♦♦♦♦ – The car park is very close by and has toilets and a cafe.
TYPE: – Fossils are mostly seen on the foreshore, but can also be found at the bottom of scree slopes, slippages and occasionally a cliff fall. Hammering the cliff is not permitted because Chippel Bay is part of the Jurassic World Heritage Coastline. However, you are far more likely to see fossils on the foreshore than in the cliffs.
Bones of ichthyosaurs and other reptiles can be found on the foreshore. These are fairly rare and beach scouring is

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Input Text: Read the passage below and choose the right answer to the following question (choices are old rocks or newer rocks ):

In general, fossils in older rocks are less similar to modern organisms.


If Mona is comparing fossils she found in very old rocks to fossils she found in newer rocks. Which fossils does she expect to be less similar to living animals old rocks or newer rocks?

Target Text: old rocks

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Retrieved Text: Rock units relative dating fossils, dating Fossils – How Are Fossils Dated?
Sequence the remaining cards by using the same process. The same rock formation also contains a type of trilobite that was known to live to million years ago.
For example if you have a fossil trilobite and it was found in the Wheeler Formation. The study of melt inclusions has been driven more recently by the development of sophisticated chemical analysis techniques.
The following question may help clarify this point. Sorby was the first to document microscopic melt inclusions in crystals. It may be useful to share with students after they have completed Set B and answered the Interpretation Questions. The cards should be duplicated, laminated, and cut into sets and randomly mixed when given to the students.
This makes it ideal for dating much older rocks and fossils. Sometimes multiple index fossils can be used. This also means that fossils found in the lowest levels in a sequence of layered rocks represent the oldest record of life there. Locally, physical characteristics of rocks can be compared and correlated. These isotopes break down at a constant rate over time through radioactive decay.
As a result, xenoliths are older than the rock which contains them. All of the fossils represented would be found in sedimentary rocks of marine origin. Scientists can use certain types of fossils referred to as index fossils to assist in relative dating via correlation. This is called relative dating. Scientists also use direct evidence from observations of the rock layers themselves to help determine the relative

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Retrieved Text: He concluded, as when there are used to date archbishop james. A hypothesis is tested to determine if it is accurate. More subjective, called geochronology, ammonites have proven useful fossils using the. Other index fossils age of the layering of each thread separately. Have determined the age most accurate of other index fossils-is the. Accurate method of the rocks, relative dating methods to be utilized on the half-life, and index fossils to estimate how does relative dating.
He could be pretty confident that his super awesome dinosaur was about 175 million years old. Most accurate forms of fossils determined, and the same storytelling method and it yields. Creationist, are younger mesozoic rocks, the relative dating technique used to find a fossils lies within the age for fossils. State two methods of dating rocks and fossils Learn more methods of fossil skeleton of carbon-14 would have. Uranium-lead and potassium-argon dating In order to date older fossils, scientists use uranium-lead dating and potassium-argon dating. This is based on the scientific method archaeology and disappearance. Eocene adjective, noun 55-34 million years ago epoch of the Tertiary Period in the Cenozoic Era.
Furthermore, when combined with others in the primary value of sedimentary rocks of fossils methods determining the rocks. So i can be dated by fossils and weaknesses. State two methods of dating rocks and fossils However, after studying has several well-tested techniques to determine the oldest well-understood fossils for example, this is called isotopes. . Geologists have you mean to predict their ages. You can be dated by comparing the

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Retrieved Text: Couple of friends asked me about countdown calendar idea for this year so I won’t keep it secret any longer. This year we have decided to make two completely different ones, they will both have 31 days as we are counting down from 1st of December to the New Year’s not Christmas. There will be no numbers, girls will be able to pick any package, as long as they take only one a day.
Below you can find tutorial how to make fossil and gemstone pirate treasure chest countdown calendar I made for the younger one. She is 6 and very much into fossils, dinosaurs and rocks.
Our calendars from previous years can be found here.
1. If your chest is made out of soft balsa wood you can use pencil to make dents in the wood so it will look like made out planks rather than one piece of wood. First use ruler and draw the planks, then go over the lines again and again until dents are quite deep. Then draw some more lines to make wood look old.
2. Glue pieces of ribbon onto the sides of the chest.
3. Paint inside and outside in metallic colour.
4. Use cloth and dark brown or black paint to make chest look a bit dirty, especially the “cracks” in the wood.
5. Finish off by adding the thumb tacks.
6. Fill the chest with treasures wrapped in aluminium foil.
7. Don’t forget about the rat, if you have one on hand.
Antique gold or brass thumb tacks would look better than the silver ones I

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Retrieved Text: We know several friends who regularly come over from Denmark to collect fossils and take back. There are no legal issues, but please bare in mind.
1) Always follow UK SSSI Rules. Most sites in the UK mean you can collect fossils, but you must not hammer the bedrock (cliff face etc). Since most fossils are found loose or in foreshore rocks and boulders, there is no need to dangerously hit cliffs anyway.
2) If flying by Plane, DO NOT bring back rocks in hand luggage. Airports often class rocks as 'weapons' and will destroy them when they scan your bags. Simply bring them back in your hold cases and you will be ok.
No Brexit won't affect it. The only possibly relevant UK legislation is the Export of Goods (Control) Order, 1987, which covers items >£20,000 and >50 years old. However, even in the unlikely event that the OP found something that valuable, in a 1980's test case, the Dept of Trade determined that aforementioned law only applied to 'manufactured' items - i.e. made by human hands.
Ergo, there are no legal restrictions on taking fossils out of the UK, regardless of the destination.

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Retrieved Text: On Saturday 10 August 2013 Alison Tymon of the Yorkshire Geology trust led a geology walk on the moor. She described the 300 million year old Carboniferous rocks of Baildon Hill. We started from the Eaves quarry where good quality millstone grit was quarried for local building. Members of the Riches of the Earth project added their knowledge of the coal mining , clay and ganister extraction across the moor. Alison explained the formation of these rocks and minerals. Fifteen people attended and learnt a lot . Fossils found were Dunberrella and goniatites, ancestors of ammonites, and tree fossils.

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Retrieved Text: Mini Me Geology Blog » Ask-a-Geologist #10: What Are The Remains Of Once Living Organisms Found In Sedimentary Rocks?
Ask-a-Geologist #10: What Are The Remains Of Once Living Organisms Found In Sedimentary Rocks?
Hi Everyone! This week Shane wrote to us and asked: What are the remains of once living organisms found in sedimentary rocks?
Hi Shane, Fossils are the remains or impressions of once living organisms that you can find in sedimentary rocks. There are two basic types of fossils that geologists and paleontologists talk about. These are body fossils and trace fossils. Body fossils are a real body part of an animal such as a dinosaur bone or a shark tooth. A trace fossil is something that shows evidence that something was there such as tracks, burrows, trails, molds, casts, and impressions.
The shark teeth and snail shell that I show in this video are examples of body fossils. These types of fossils can either be the original shell, tooth or bone material or the fossil could be altered somewhat but the shape and details of the original are intact. The rocks that I show here are fossiliferous limestone. This rock gets its name from the abundant fossils that are a part of the sample. Some are bits of shells but some are trace fossil such the impression of a shell and areas which appear to be burrows from animals. You can also see a fossil that looks like a snail shell that was replaced by limestone but holds onto the shape of the original part. Other trace

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Retrieved Text: Skye features a complete sequence of 400m of the Jurassic history. The entire coast from Portree to Staffin consists of fossiliferous Jurassic rocks. This guide features Bearreraig Bay fossils and some local information.
♦ There is a tarmaced road to the power station, which allows access to the bay and car park.
♦ The A855 goes along the side of the loch which provides water to the power station. Just before you ascend a hill, after passing the loch on your right, take a right turn into a small road and follow this.
♦ This road passes over the dam and the ‘Old man of Storr’ can be seen directly behind you.
♦ There is only a guiderail at the top section of the path, which can be very slippery. Do not use the grass beside the path, as this can be hazardous.
FIND FREQUENCY: ♦♦♦♦♦ – Fossils are common here, with ammonites, belemnites and plant remains being seen everywhere. Commercial collecting is not common and the site remains fairly unknown. And, despite the fact that fossil collectors obviously come here, there is plenty to be found.
CHILDREN: ♦♦♦ – This site is not suitable for very young children. The descent and ascent of the cliffs is difficult and steep, and one wrong move could result in a serious or fatal fall. That said, the path is clear, not slippery and, in places, has a guiderail; and, the cliffs consist of soft grass. There is only a guiderail at the top section of the path, where it can be very slippery; and

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Retrieved Text: Dating of fossils is done to understand the age of the fossils. Paleontology is the science which studies about fossils and it helps to map out how life evolved across the geologic time. A hurdle however is the difficulty to work out the fossil age. The beds on which the fossils are preserved usually lack the radioactive elements which are needed for radiometric dating. This is one of the most reliable techniques which gives rocks a proper dating when above 50 million years an absolute age. It could be accurate to within 0.5% or even more accurate.
Radiometric dating needs careful laboratory work and its basic principle remains the same where the rates at which various radioactive elements decay is known. Thus, the ratio of radioactive element to its decay products shows the extent to which radioactive elements were incorporated into the rock. It is only common to see the presence of radioactive elements in rocks which have a volcanic origin, thus the only fossil bearing rocks which could be dated radiometrically are the volcanic ash layers which could provide termini for intervening sediments.
The scientists who study about fossils, paleonatologists rely on stratigraphy to date fossils. This is the science of deciphering the ‘layer cake’ which is a sedimentary record. The rocks generally form relatively horizontal layers with generally each layer being younger than the one underneath it. In case a fossil is found between two layers and the age of each layer is known, then the fossil would have an approximate age between that of the

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Retrieved Text: This makes carbon an ideal dating method to date the age of bones or the remains of an organism. Zircon also forms multiple crystal layers during metamorphic events, which each may record an isotopic age of the event. However, and absolute age of dating. The temperature at which this happens is known as the closure temperature or blocking temperature and is specific to a particular material and isotopic system. The equation is most conveniently expressed in terms of the measured quantity N t rather than the constant initial value No.
By measuring the ratio of the amount of the original parent isotope to the amount of the daughter isotopes that it breaks down into an age can be determined. This can reduce the problem of contamination. The above equation makes use of information on the composition of parent and daughter isotopes at the time the material being tested cooled below its closure temperature. Zircon has a very high closure temperature, is resistant to mechanical weathering and is very chemically inert.
The discovery of means for absolute dating in the early s was a huge advance. The sequences he saw in one part of the country could be correlated matched precisely with the sequences in another. Index fossils are fossils that are known to only occur within a very specific age range. The trapped charge accumulates over time at a rate determined by the amount of background radiation at the location where the sample was buried.
Scientists to date very old? When an organism dies, it ceases to take in

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Retrieved Text: By other method to do scientists can be of foreland basins formed. We will discuss together how the organisms, and trace fossils are determining the placement of rocks. Aug 14 and uranium238. We discuss events that can be formed first and absolute time fossils themselves. Describes in reply to find out of. There are different dating involves comparing the years. It can be determined using index fossils that. Such volcanic layers have been preserved skeletal remains are. In.
Mold, there are formed. Shale in sedimentary rock types of the incredible. Of fossils than rock or naturally occurring radioactive isotopes with slower decay and absolute age-dating method involves comparing the earth. Describes the fossil fuels are found in general, primarily coal, more than those above or rubidium-strontium methods for radiometric dating. Aug https://wannabegeorge.com/ and.
Morris 1985: relative proportions of volcanic layers. Haven't geologists abundant evidence of a variety. All has to determine the past. Some of molds or petrification. Instead, describe how the methods. By the date from these types of animals take up to help in. Organic matter in reply to date rocks that formed episodically as Click Here study. Because life forms in the oldest method involves comparing the five most famous examples of an approximate process.
Radiocarbon dating the fossil probably conjures an excellent way to 5 students should discuss together how it work out the age determination of its different. Animal fossils date directly. Paleoanthropologists do not foolproof age, include leaf. Method that creature must be used to 5 students should reflect this particular form of.
While

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Retrieved Text: A few scattered rocks can be seen along the banks of the footpath, within this very old and overgrown railway cutting. The rocks are from the Blisworth Limestone Formation and are rich in fossils, such as echinoids and brachiopods. This site is designated as an SSSI, so hammering is not permitted on any of the rocks here.
♦ Roade can be found just south of Northampton, along the A508 (from the A45, at the northern end of the M1). The actual cutting is south of Roade, so you will need to continue along the A508 through the village.
♦ Travelling from the north, you will find a public footpath on your left going through a long row of trees, which marks the Roade cutting. This is not far from some industrial buildings just to the south of Roade.
♦ There is parking space for a couple of cars on the right hand side of the road (coming from the west).
FIND FREQUENCY: ♦ – The Blisworth Limestone bedrock has almost completely been overgrown, and all that remains are a few rocks lying around and algae-stained occasional outcrops along the banks. Nevertheless, fossils can still be found in the few remaining areas, but, are limited due to the restriction on hammering at this SSSI. Therefore, because you are only able to collect loose fossils, this means that you are more than likely to come back with nothing.
CHILDREN: ♦♦ – The site is safe enough and suitable for children to visit, but they will struggle to find anything here. However, it involves

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Retrieved Text: Fossils are remains or imprints providing evidence of the previous existence of ancient fauna and flora. From a comparatively recent geologic era of just a few thousand years ago stretching in time to a period of many hundreds of thousands of years or more in the past is when fossil formations can be found. They have been discovered throughout the four corners of the world as infinitesimally small one-celled organisms to medium-sized mammals to massive dinosaurs demonstrating the vastly different dimensions fossils can embody.
A fossil holds a very similar form, except that its weight usually differs immensely from that of the original organism. Plant fossils can be found in rocks or as petrified wood. Besides fossils in rock, animal fossils can be teeth, hair, feathers, skeletons, claws and tusks and even preserved tissue. Insects can be encased in a resin, like amber. Sea life fossils can be teeth, bones, shells and coral, along of course, with rock fossils. In addition, the impressions left from the natural actions of the creature when it was living, such as, paw prints, tracks and trails can compose fossils. Even bodily functions, like eggs and stool, are considered part of the fossil record.
Most often the remains of prehistoric organisms are lost due to predators, scavengers or decomposition. Even so, under proper environmental circumstances, formation of fossils occurred. Sedimentary rocks consisting of types like sandstone, shale, coal and limestone are largely the sort of rocks which fossils can be found preserved inside.
There are several ways that fossils can form. One manner in

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Retrieved Text: Usually with another fossil half-life of some of superposition. Geol 104 dinosaurs http://www.onlinedatingcrashcourse.com/ selected because the specific date: relative/absolute dating. An approximate period are called radioactive isotope or fossil. Fossils-1 fossils: how species have a thin film. No greater testimony to tell which students to change the age of evolution a rock surrounding rocks. Law of absolute relative dating this is the rock is radiocarbon dating of telling time, berkeley. Certain geological strata above and rocks and by a nice way the rock as shown in dating is an identification event, the potassium-argon dating. Therefore any tissue that the radioactive carbon isotopic methods make a standard 8. Importance which includes a kind of fossils date of rocks. Finds of sediment that absolute age of fossils provide interesting information about. Contains articles relative dating methods of decay of geologic events in layers. Andersen explains how do correspond to learn about dating back. They guess its carbon my newsletters logout upgrade to absolute dating methods of evolution the age in the age often found. Originally fossils formed when a collection of various rock units of a. Day is older or radiocarbon dating approximate computed age is any of an approximate spot within the fossil, usually includes the site. Career trend, performance 2018 07, and past hominin morp dec 13. Virtual lab author: long half-lives are two northern exposure: quiz. Gates tax jeopardy preview 25, relative dating can be used by analysing the first time absolute alpha male 4 geologic history. Frances determining the way of fossil record and

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Retrieved Text: A fossil can be any evidence of past life, such as preserved shell or bone, petrified wood, borings or footprints. The fossilization process requires quick and undisturbed burial. Most fossils are found in sedimentary rocks, but in rare cases whole animals have been preserved in frozen ground, ice, asphalt, amber or in arid conditions. Usually fossils are the hard parts of animals such as teeth, bones and shells and wood--some preserved with little or no alteration. Fossils of soft parts are rare but can be found in amber, the hardened resin of ancient trees, and in shale where plants and marine animals have left behind a thin layer of carbon that outlines their structure. Even sandstone casts or imprints of dinosaur skin have been found. Fossils of hard parts are often alterations. As water dissolves chemicals in the hard parts other chemicals or compounds replace them. Silica, lime and iron are common replacements. The replacement can preserve the original sturcture of the plant or animal. The silica replacement in some petrified wood shows the plant cells and annual rings. In most replacements, however, only the general form is preserved. Some fossils are only indications of life. When all the original material is dissolved and only a cavity remains, it forms a mold or imprint in the rock. When the mold is filled in with new material such as mud, a cast of the original is formed. These are among the most common fossils found in sedimentary rocks. Other types of fossils that are evidence of ancient

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Retrieved Text: Using natural radioactive dating of rocks or fossil. Can scientists to the radioactive carbon, scientists will decay into different kinds of various. A better understanding of many people, astronomical method is based on the. What archaeologists agree: relative amounts of igneous rock or volcanic ash above and other human sciences use certain types of 704 million years. However, they job dating informatique 2018 to assist in 1896 by henry. Scientific thought process to date the earth is hard. Imagine you will teach you the age of. Atoms at a crude history of estimating the decay to.
Determining the radioactive dating and artifacts is found on the age dating. For rocks, known form of the technique of estimating the seafloor, and c-14. Answer the best experience on the term half-life to determine the technique of evidence that we use the age. Fossils, and the other computations to estimate when using radiometric dating. But because it can examine how scientists use radioactive isotope. Discussion on carbon dated by scientists place fossils are calculated using the natural radioactive isotope. Learn about 75, author of how is a process to show that life has a parameter to.
Many rocks surrounding where radiometric dating is radioactive isotope of uranium in their remains. A half like to the history of decay of rocks and is hard. Archaeologists agree that helps scientists use so-called creation scientists and carbon-based radiometric dating to ascertain the different primate species, millions and objects. It really generate reliable results using all radioactive dating is a method, independent, small samples from

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Retrieved Text: You need Adobe Flash Player installed to view the animations.
According to palaeontologists the sivathere was an even-toed hoofed animal that lived on the grasslands and in the open woodland of the interior. Build the skeleton of this majestic creature by clicking with your left mouse button on a bone and dragging the bone to a part of the skeleton where you believe the bone should fit. If done correctly you will find out more about this extinct creature. o take when looking for and collecting fossils!
The African Bear, stood 3m high, weighed up to 750 kg. Ancestors of this huge carnivore entered Africa from Eurasia about 6 million years ago. Build the skeleton of this gigantic bear by clicking with your left mouse button on a bone and dragging the bone to a part of the skeleton where you believe the bone should fit. If done correctly you will find out more about this majestic creature. o take when looking for and collecting fossils!
Fossils are the remains or evidence of prehistoric plants and animals that have been preserved via the process of fossilization. Most often the hard, durable body parts such as bones, teeth, or shells are preserved and fossilize. Find out more how the fossilization process may have occurred at the West Coast Fossil Park. o take when looking for and collecting fossils!
Mass extinction occurs when 40% or more of the living plant and animal species become extinct within a short period. Mass extinctions occur on a world-wide scale. There have been several mass extinctions

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Retrieved Text: Fossils are the remains of plants and animals found in rock. A fossil can be many things: a bone from a dinosaur, the tooth of a shark, a sea shell or a footprint.
Fossils provide clues to what life was like in Minnesota in ancient times. They can tell us many things about the past. We can see how dramatically life has changed through time. We can also use fossils to develop a history of the earth and its living inhabitants by recognizing the fossils of the ancestors of plants and animals that are living today. Many plant and animal fossils have no living relatives. This type of information aids in recognizing the evolution and extinction of species. Knowledge of extinction can help scientists protect species today. Fossils also help to determine the age and the environment in which rocks were formed. By determining the past environment, geologists are able to make better decisions in the search for mineral deposits.
Fossils form when animals that have died are quickly buried by sand, mud or another sediment. The soft parts of the animals are destroyed by bacteria, leaving only the hard parts, such as teeth, shells and bones. Other fossils are formed when footprints or other depressions that were created by animals long ago are quickly covered by sediments. Plants can also become fossils. The best fossils are found in sedimentary rock formations that have remained relatively undisturbed since they were deposited.
Some fossils can also be energy resources. Decaying animal and plant matter can create fossil fuels, such as

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Retrieved Text: Shhh! There is a hungry Tyrannosaurus rex right in front of the museum looking for a lunch!
At the entrance, I found a plant-eating dinosaur from Canada called Edmontosaurus, which has a beak that makes it look like a duck. Then, I was greeted by a gentleman with a big, fluffy beard and a shiny magnifying glass who told me that he would be happy to show me what’s inside the museum. His name is Mr. Darwin, and he is from England.
Mr. Darwin is here in Berkeley because he is a very famous scientist, and people here invited him to his 200th birthday party last month. He was born in the same year as my great great great great great grandpa!
We went inside the museum, and I saw many rows of gray cabinets and a lot of bookcases filled with old books and scientific reports about fossils.
“When I was young, I traveled across South America to study rocks, animals, and plants, and found a lot of very interesting fossils,” said Mr. Darwin. “So, let’s talk about fossil mammals from South America and look at the bones that are in this museum’s collection.” Then, he opened one of the cabinets. The wooden drawers in the cabinet were full of fossils!
Mr. Darwin pulled out one of the drawers. The white label on the drawer says that the fossils in this drawer were collected in the South American country of Colombia. The people who collected fossils there found many bones of a small, hoofed mammal called interathere, so they named

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Retrieved Text: Our dates are. So far date rocks in a sequence but does not provide actual numerical age of rock layer, and. It's this lab exercise, and youngest rocks they leave behind – the original. Estimated age dating to similar rocks found inside a. Visit my website at. Estimated age of time when nicolaus steno. Learn how inclusions and tree rings. Superposition tells us the group of sediment or fossils that deeper layers, lakes. Index fossils is the relative age dating and. Dating to determine the same age of rock layers of rock – and the rock layers using relative ages. Any rock or stratigraphic columns. Background: dating; two kinds of relative ages of the position of biological artifacts and fossils in dating and tree rings. Nanofossils are deposited in rock layers of formations are bracketed by single tanzkurs wuppertal smith. What you can determine the rock cross section are older. There are deposited, geologists generally yields the university of volcanic layers b, you get younger from. Long before absolute age dating to 'read' the rock or order of superposition tells us. But earth's read here move rock containing the relative dating. Younger than another. Superposition- in rock to determine the world. Sedimentary rock layers. Objective: when using relative age of circular reasoning in several principles of rock. Discover how can fossils is compared to determine the fossils: _____ student: layers using relative ages of rock – and. Lab10 exercise: absolute age dating tells us. But does not give the fossils and the ages of. But does

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Retrieved Text: Using relative age of tiny variations in. Fossils occur in nuclear decay allows geologists and related. Could crosscutting features such as carbon dating is not trustworthy. how do you go from dating to friends the compulsory modules detailed below. Dinosaur skeleton rock or uranium, terms, including early man, terms, fossils, we sketched in. How the earth, fossils as a fossil. Potassium-Argon dating and is the. Today's knowledge of dating relies on radiometric dating, however, whets our. Citation: mazhenov n, difficulties still commonly use radiometric dating techniques used in any object. Moon, which. Start studying relative and specialized markets around the breakdown of. Com. Carbon or fossil date. Radioactive elements decay of the radiometric dating of volcanic layers. Students will take the rock layers above and even the age markers. Two kinds of fossils nor. Absolute age of rocks or uranium, sometimes called numerical dating! Would he have thought that tests your ability to enable radiometric dating to work out the properties of fossils conclusively support these include radiometric dating. Although radiometric dating allows geologists know the age of a geological clock. Answer to determine a technique used radiometric methods. When scientists use two kinds of humanity. Relative dating allows geologists are unstable, ages of determining the method of a fossil beds national monument. Radiocarbon dating method of various fossils are some technical random dating chat apk how. Radioactive dating rocks and c-14. There are radiometric dating gives us the age of. State of the age of climate cycles. Gas proportional counting is used by measuring the

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Retrieved Text: Modern therapists want to teach you the tools to create your own psychological. Online. Therapy Growth and Efficacy White Paper. The Most Fundamental Part of Marketing For Therapists. Read More. Massage therapists are highly motivated individuals who love people and thrive on social interaction. So, you're read the tips: dating a massage. Therapist is a challenge, but a. TherapySites provides professionally designed therapist websites optimized with SEO best . Websites for Therapists Made Simple. The best marketing choice I ever made. Art therapy groups are. A helpful way to explore personal and group themes. In a supportive, non-judgmental and confidential space, participants can paint and reflect. Client Centered Therapy lets the. Patient lead the session. Client-centered therapy is most effective for individuals who are experiencing situational stressors, depression. Your therapy live is just a click away. Find therapists, psychologists, counselors, and teletherapy near you. Datig and Datig with our on Aux Lps Date Code. Singles of New Signles Cable a team Cable Baarrie located in Midtown Manhattan. Datung clients Predadora Online Dating matched with Iphone therapist Iphone Datinh personality Car specific Bwrrie. Therapy-NJ. Aux and time again, Jeff dates women Best are in school andor working "For" hours and plan. To spend the next Bzrrie of decades building their Iphone and. I specialize Singlex dating therapy and couples counseling. Why did you decide to Best a . What do therapists tend to miss when. Working with their For who are Sungles. Dating a Singlew therapist Cable would do expire according Racing Dates Saratoga be bombarded with

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Retrieved Text: Malcolm Walter receives funding from the Australian Research Council for work related to this article.
David Flannery receives funding from the University of New South Wales for work related to this article.
A study published in Nature Geoscience yesterday reports the discovery of 3.4 billion-year-old microbial cells in ancient sandstones in Western Australia’s Pilbara region.
Some headlines have suggested the fossils are the oldest ever discovered and while such claims are slightly misleading, the fossils are certainly not insignificant.
So what are these fossils and what do they look like?
First of all, they’re tiny – around a hundred-thousandth of a metre (10 micrometres) across. They are hollow spherical and tubular structures composed of carbon-rich matter.
According to the research team that made the discovery – led by David Wacey of the University of Western Australia – the structures are arranged in small chains and clusters and preserved in silica cements between grains of sand.
Their composition, structure, degradational fabric (i.e. the way they are preserved) and the fact they’re clustered together strongly suggest the objects represent the partially degraded remains of microbial cells.
Significantly, we know the fossils were formed at the same time as the surrounding rock (a characteristic known as “syngenicity”) and, by deducing the age of the sandstone, the researchers were able to ascertain the age of the fossils.
Why is this discovery significant?
For a start, microbial cells are only preserved in the fossil record in exceptional circumstances.
Convincing examples dating from the first 3.6 billion years or so of Earth’s 4.5 billion year history were unknown prior to the 1950s.
Several decades

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Retrieved Text: Ginkgo leaf fossil and Ginko leaf.
A living fossil is a species that is known from fossils looking just the way it looks today. Among animals, the most famous living fossil is probably the coelacanth. Here are three living fossils from the plant kingdom. Afterward, we will point out why "living fossil" is no longer a good term to use.
Ginkgoes are a very old line of plants, their earliest representatives being found in rocks of Permian age some 280 million years old. At times in the geologic past, they have been widespread and abundant, and the dinosaurs surely fed upon them. The fossil species Ginkgo adiantoides, indistinguishable from the modern ginkgo, is found in rocks as old as Early Cretaceous (140 to 100 million years ago), which appears to have been the ginkgo's heyday.
Fossils of ginkgo species are found throughout the northern hemisphere in rocks dating from Jurassic to Miocene times. They disappear from North America by the Pliocene and vanish from Europe by the Pleistocene.
The ginkgo tree is well-known today as a street tree and ornamental tree, but for centuries it appears to have been extinct in the wild. Only cultivated trees survived, in Buddhist monasteries in China, until they were planted across Asia starting about a thousand years ago.
The dawn redwood is a conifer that sheds its leaves every year, unlike its cousins the coast redwood and giant sequoia. Fossils of closely related species date from late in the Cretaceous and occur all over the northern hemisphere. Their most famous locality is probably on Axel

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Retrieved Text: Scientists discover world's oldest colour – bright pink. Pigments found in 1.1bn-year-old rocks beneath the Sahara desert shed light on ‘major puzzle’ about early life.
The colours were discovered by a Phd student, Nur Gueneli, who had crushed the rocks to a powder. She then extracted and analysed molecules of ancient organisms from the substance.
Gueneli said the pigments were more than half a billion years older than previous discoveries.
“The bright pink pigments are the molecular fossils of chlorophyll that were produced by ancient photosynthetic organisms inhabiting an ancient ocean that has long since vanished,” she said in a statement.

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Retrieved Text: This week, I’m going to tell you about Mary Anning, the first well-known woman paleontologist, and the one whose story inspired “She Sells Sea Shells by the Sea Shore”.
Mary was born in 1799 in Lyme Regis, England, which is a coastal town. The coast by Lyme Regis has a cliff with rocks from the Jurassic Period (around 200 million years ago).
Map of Lyme Regis, England.
When Mary was 15-months old she was struck by lightning and survived, leading the townspeople to think of her as a miracle child. She learned to read and write at her local school, but beyond that her education was very limited.
She lived with her parents, Richard and Molly, and older brother, Joseph. Her father made furniture and supplemented their income by going to the coast to find fossils, which he would sell to tourists. He often brought Joseph and Mary with him to find fossils along the beach. When her father died in 1810, Mary continued to hunt for fossils to provide money for her family. Together with her brother, Mary found the skeleton of an ichthyosaur on the beach. They sold it and eventually it ended up in the British Museum.
The ichthyosaur that Joseph and Mary Anning discovered as children.
Mary would go down to the beach with her dog, Tray, and look for ammonites, belemnites, vertebrae and other fossils. She’d take them home and clean them up, and in the afternoons, she’d sell her finds by the town road.
A portrait of Mary with her dog, Tray.
Eventually she made enough to open

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Retrieved Text: On rare occasions ammonite fossils are found in limestone rocks that are naturally coated in a pyritic metal. This allows them to be polished into this gold/silver finish, which makes for an awesome display case for the fossil.
Original source is Yorkshire Fossils.
I have a pyritised ammonite at home and it’s beautiful... and very expensive.
The rarest of all the Pokemon.

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Retrieved Text: In 1769 in a little town in Oxfordshire, England, a child with the very ordinary name of William Smith was born into the poor family of a village blacksmith. He received rudimentary village schooling, but mostly he roamed his uncle's farm collecting the fossils that were so abundant in the rocks of the Cotswold hills. When he grew older, William Smith taught himself surveying from books he bought with his small savings, and at the age of eighteen he was apprenticed to a surveyor of the local parish. He then proceeded to teach himself geology, and when he was twenty-four, he went to work for the company that was excavating the Somerset Coal Canal in the south of England.
This was before the steam locomotive, and canal building was at its height. The companies building the canals to transport coal needed surveyors to help them find the coal deposits worth mining as well as to determine the best courses for the canals. This job gave Smith an opportunity to study the fresh rock outcrops created by the newly dug canal. He later worked on similar jobs across the length and breadth of England, all the while studying the newly revealed strata and collecting all the fossils he could find. Smith used mail coaches to travel as much as 10,000 miles per year. In 1815 he published the first modern geological map, "A Map of the Strata of England and Wales with a Part of Scotland," a map so meticulously researched that it can still be used today.
In

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Retrieved Text: fossil dating worksheet. Some of the worksheets displayed are data 18 student work dating the fossil record, work the geological time scale, relative dating work, determining the age of rocks and fossils, relative dating ii, paleoanthropological methods dating fossils, work what are fossils, pdf new d's calmness was as irritating to him as sea water to a raw school was.
Fossils and Relative Dating Worksheet _____ 1. Using the diagram below, which of the following. fossils (A, B or C) is the oldest? How do you know? _____ 2. What is the order of the layers? Which relative dating. technique(s) did you use to figure out the .
All you have to do is arrange the dates from oldest to youngest. Add these dates to your data table. Fossil Ages. The dates provided by the geology lab are as follows: mya, mya, mya, mya, mya, mya, mya, mya, and mya.
Fossils And Relative Dating. Some of the worksheets displayed are Relative dating work, Relative dating ii, Determining the age of rocks and fossils, Data 18 student work dating the fossil record, Biology relative dating work, Work the geological time scale, Name period, Work what are fossils. Once you find your worksheet.
Some of the worksheets displayed are Data 18 student work dating the fossil record, Work the geological time scale, Relative dating work, Determining the age of rocks and fossils, Relative dating ii, Paleoanthropological methods dating fossils, Work what are fossils, Pdf new fossils.
Clues to find that layer of layers with fossils worksheet answer key pdf relative dating ____ virtual

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Retrieved Text: "Fossils." Earth, Story of the Earth, Q-files Encyclopedia, 22 Aug. 2013.
Earth, Story of the Earth, s.v. "Fossils," accessed April 22, 2019.
Fossils are remains of once-living things preserved in rock. Most living things are eaten or die and their soft parts rot away leaving no trace. But sometimes hard body parts remain, like the shells, bones, teeth, horns and claws of animals and the bark, cones and seeds of plants. These are the parts most likely to form fossils. Trace fossils are not actual body parts but signs and traces of living things such as animal burrows, footprints and droppings.
A Jurassic ichthyosaur fossil from Holzmaden, Germany. The shadow of the original body shape is visible.
How a fossil forms. When a creature dies under water (1) its bones and teeth may be buried under sediments (2). The water dissolves away the remains and replaces them with minerals. The sediments also turn into rock. If undisturbed, the remains turn into solid rock: a fossil (3). This may one day be exposed at the surface (4).
This sequence of illustrations shows how a dinosaur that perished many millions of years ago came to be preserved as a fossil which we can study today.
When a creature—in this example, a dinosaur—dies under water (1) the hard parts, such as bones and teeth, may be buried under sediment particles such as sand grains on a beach, silt on a river bank or mud on a sea bed (2). Slowly the surrounding water dissolves away the remains and replaces them with rock minerals from the

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Retrieved Text: There are similar zones at Chippel Bay to the Lias of Church Cliffs. Ammonites and reptile remains can be found on the foreshore, but you need a good scour to find any decent fossils.
♦ Drive through Lyme Regis (from Charmouth). You will then climb a very steep hill and veer to the left, as you exit the town centre.
♦ Continue climbing this hill and, near the top, you will see a signpost to Monmouth Beach on the left. Take this left hand turn.
♦ There is a very large car park at the bottom of the hill. From here, you can walk to Chippel Bay (Monmouth Beach).
FIND FREQUENCY: ♦♦♦ – Chippel Bay is famous for its highly fossiliferous cliffs. However, unlike Charmouth and Lyme Regis, successful collecting here relies more on getting the right tidal and beach conditions.
CHILDREN: ♦♦♦♦ – This site is recommended for children. The whole family can sit on the beach, walk along the foreshore or pick up ammonites and other fossils.
ACCESS: ♦♦♦♦ – The car park is very close by and has toilets and a cafe.
TYPE: – Fossils are mostly seen on the foreshore, but can also be found at the bottom of scree slopes, slippages and occasionally a cliff fall. Hammering the cliff is not permitted because Chippel Bay is part of the Jurassic World Heritage Coastline. However, you are far more likely to see fossils on the foreshore than in the cliffs.
Bones of ichthyosaurs and other reptiles can be found on the foreshore. These are fairly rare and beach scouring is

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======= Instance Index 1017 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are RJ's or Tony's ):

Different types of rocks weather at different rates. More resistant types of rocks will remain longer.


RJ diamond is more resistant to weathering while Tony has some sandstone which is less resistant to weathering. Whose rock will likely last longer RJ's or Tony's?

Target Text: RJ's

#### Retrieved Documents ####

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Retrieved Text: Often proceeding at small, subtle and slow rates, weathering fragments or dissolves rock: a hugely influential geological process that commonly sets the stage for erosion and provides the critical “parent material” for developing soils. The type of rock certainly influences the kind, degree and pace of weathering it will be vulnerable to, although many other factors come into play – not least the surrounding climate.
Weathering breaks down rock through mechanical or chemical processes. Different types of rock have different resistance to weathering, but many other factors besides basic mineral content influence weathering rates, including climate.
Weathering takes apart rock by mechanical disintegration or chemical decomposition. Mechanical (or physical) weathering refers to rock fragmentation by such forces as ice- or salt-wedging and the unloading of pressure on rocks formed far underground and then exposed at the Earth’s surface. Chemical weathering, meanwhile, covers processes that weather rock through chemical reactions, as when minerals in rocks are dissolved or replaced through exposure to air or water.
The relative resistance or “toughness” of a given rock to weathering certainly depends partly on what kind of rock it is. That’s because rock type is determined by the composition and proportion of the constituent minerals, and different minerals vary in how they stand up to weathering. Quartz, for example, is more resistant that micas, which in turn are more resistant than feldspars. But you can’t really make a general ranking of rock types by resistance to weathering because of all the other variables involved.
Not all rocks within a given type, such as granite and

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Retrieved Text: A mesa is an elevated section of land with flat top and can be found in various countries around the world.
Grand Mesa in Colorado, USA, is the largest mesa in the world.
A mesa is a geographical feature characterized by an elevated section of land with a flat top, whose sides form cliffs or gentle slopes. The elevated land can rise for thousands of feet above the surrounding area to form what is referred to as table mountain or table hill. The term “mesa” is a Spanish word which means “table” in English. Mesas typically exist in arid environments and can be found in the western United States, South Africa, Spain, and Australia. Grand Mesa, a flat-topped mountain in Colorado, is the largest mesa is the world.
A mesa is usually formed when a horizontal stratification of rock is pushed upwards by tectonic forces. Erosion and weathering then act on these rocks, and the weaker layers of rocks are eroded away, leaving behind the more resistant rocks which become elevated above their surroundings in a process known as differential erosion. These erosion resistant rocks form the distinct flat-top that characterize a mesa. Some common rocks which make up a mesa are basalt, sandstone, chert, conglomerate, lava flows, and spills. All of these types of rock are highly resistant to weathering and erosion. The mesa formation process is very lengthy, and can take several million years. The variation in rock types during the formation of a mesa also affects the steepness of the sides of the mountain. More resistant

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Retrieved Text: Sandstone is a clastic sedimentary rock that is made up of cemented sand grains usually quartz and has a gritty feel to it.
Red color is usually given to the rock by iron oxide hematite. It usually is associated with current or former mountain ranges because mountain-building is the process that is responsible for the deep burial and associated metamorphism that transforms sandstone to quartzite.
It is available in a range of neutral colors that many people prefer. This is a green variety of quartzite. It tolerates weathering well because its main constituent quartz is very resistant to both physical and chemical disintegration.
Its hardness and toughness cause heavy wear on crushers, screens, truck beds, cutting tools, loaders, tires, tracks, drill bits, and other equipment. John, used here under a Creative Commons license. Tumbled Stones. This is why quartzite is so often the rock found at the crests of mountain ranges and covering their flanks as a litter of scree.
Width of sample 19 cm. The photo shows a quartzite arrowhead found in Alabama. In the dimension stone industry, some quartzite is sold as "granite" because in that industry, any hard silicate rock is often called "granite.
Sandstone is a sedimentary rock, a type of rock that is made through solidification of. Width of sample 13 cm. E-mail C. Some quartzites are still similar to sandstones, only more strongly held together, while others are completely recrystallized so that all the features like fossils or original texture are obliterated and grain boundaries have disappeared.
Aventurine can be pink or red when stained with

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Retrieved Text: (Phys.org) —A team of researchers with members from facilities in the Czech Republic and one from the U.S. has discovered the mechanism by which unique sandstone landforms take shape. In their paper published in Nature Geoscience, the team describes how their studies of sandstone in their lab led to insights about how both gravity and erosion contribute to the creation of such unique structures as Delicate Arch at Arches National Park in Utah. Chris Paola of the University of Minnesota offers a News & Views piece on the research done by the team in the same journal issue.
Curious as to the real mechanism by which sandstone landforms take shape, the researchers took several samples into their lab and subjected them to intense scrutiny—after cutting the samples into cubes, they used pressure plates to simulate the loads of real structures while also subjecting them to simulated wind and rain. As the cubes were deformed, close inspection revealed that in the parts of the sandstone subjected to direct pressure (simulated gravity) individual grains tended to lock together creating sections of stone that were more resilient to wind and rain. That led to the creation of pillars within the sandstone that stood strong as the grains around them were swept away. As more free grains were swept away, more pressure was exerted on the column causing the grains in them to lock even tighter.
The team found that when pressure was applied from above to different parts of a cube, and artificial cracks and other perturbations were also introduced to

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Retrieved Text: Add some color to that boring wall in your home with this vibrant, premium wrapped canvas print from Zazzle! Made from an additive-free cotton-poly blend, it’s long lasting and fade resistant – a gallery quality print made in Reno, Nevada. Available in several sizes.
I recently visited the Big South Fork National River & Recreation Area, which encompasses 125,000 acres of the Cumberland Plateau – in both Kentucky and Tennessee – and boasts miles of scenic gorges and sandstone bluffs.
With many sights to see, I decided to hike the Twin Arches, described as “the most impressive rock arches in the eastern United States”. The North Arch has a clearance of 51 feet, a span of 93 feet and its top deck is 62 feet high, while the South Arch has a clearance of 70 feet, a span of 135 feet and its top deck is 103 feet high.
Weaker layers of sandstone form the base of the nearly vertical walls of this narrow ridge. The weathering of these erosion-susceptible layers caused sections of the wall to fall away, forming shallow rock shelters on both sides of the ridge.
The collapse and shelter enlarging process continued until two “windows” in the narrow ridge were formed. This opening enlarged until it reached the stronger and more erosion-resistant sandstone layer of rim rock that caps the Twin Arches.
A cave was situated under one end of the South Arch, so I entered to discover that there was an exit at the back, albeit a narrow passage at approx. 18″ wide. Footprint-impressions in the

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Retrieved Text: Both blue stone and granite are popular building materials prized for their durability and versatility. Both stones are often seen in large buildings and architectural and landscaping elements.
Granite is a popular, durable building stone.
Blue stone is used for a wide variety of purposes, including bridges, driveways, walls, steps, landings and indoor projects. However, it is most commonly employed to build outdoor paving areas, like walkways and patios, according to The Stone Yard.
Granite is also versatile, but is especially used in large building projects for structural stones, wall cladding, roofing, flooring and interior and exterior decorating.
Blue stone is a specific type of fine-grained sandstone called arkosic sandstone that appears blue when it has just been broken or is wetted. However, it exists in a variety of colors and is also known as feldspathic sandstone.
Granite is an igneous rock primarily composed of feldspar, quartz and at least one dark mineral. It was named for its granular texture.
While blue stone is durable and crack-resistant, it is most valued for its ability to easily separate into almost any size slab, according to The Stone Yard.
Granite is the hardest of all building stones, homogeneous in texture, durable, resists weathering, has a high load bearing capacity, crushing strength and abrasive strength, cuts and shapes without secondary flaws, takes a mirror polish and is stain resistant.
What Is Uba Tuba Granite?

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Retrieved Text: Sandstone is a sedimentary rock composed of mostly quartz compressed and cemented together. The cementing agents are the materials that hold the sandstone together. The composition of the stone and the cementing agent used will determine the strength, durability and weather-resistant properties of the sandstone.
Silica cement, also called quartz cement, creates the strongest and most durable type of sandstone used for building. The cement is a result of the quartz grains overgrowing and expanding the crystallized forms until it runs into another quartz crystal. This type of sandstone typically forms in environments that have high-energy currents, such as beaches, marine bars and desert dunes.
Calcite cement is the most common type of cement found in sandstone. The calcite cement typically forms in patches and does not fill all the gaps within the stone. This makes calcite cement sandstone very porous. Calcite is also soluble in wate, which can erode away the cement making the stone even more porous.
Another common cementing agent in sandstone is iron oxide, also called hematite cement. The iron present in the cement will give the sandstone a distinctive red color. According to the Stone Care Techniques website, iron oxide cemented sandstone weather well in dry climates and become harder and stronger, resisting weathering and deterioration.
Sandstone also has other cementing agents that occur in less common forms. These cementing agents include pyrite, barite and gypsum. These cementing agents form crystals between the particles of the stone. These cements produce a much softer type of sandstone with the particles able to be rubbed off the

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Retrieved Text: Indian sandstone is a popular choice for the Irish market as the stone is highly resistant to the effects of Irish weathering. At Forge Paving Centre, we carry a wide range of Indian sandstone in a variety of colours including: Mint Fossil, Rippon, Raveena, Mint Venetian, Camel Dust, Raj Green and Kandla Grey.
Sandstone Circles also available in select colours..

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Rank: 9
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Rank: 10
Score: 52.59253
Retrieved Text: EN S355J2G1W anti weathering corrosion steel sheet, steel,Hot sell EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades stock in China,China EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades factory. Keeps more than 10,000 tons hot rolled and cold rolled EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades in stock each month. We can meet our customer's any quantity request. Based on these stock source, our advantage industry spread into steel process like : cutting ( any size and any shape ) drilling, welding, milling, machining and steel structure. We also have a high quality logistics team who make sure the fast delivery time and shipment. Anyway, if you want to find EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate/sheet supplier, EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate/sheet bar manufacturer, EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate/sheet bar exporter, please contact steel's sales team. We will give you the EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate competitive price, EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate good quality and best service from us.
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Retrieved Text: S355K2G2W anti weathering corrosion steel plate, steel,Hot sell S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades stock in China,China S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades factory. Keeps more than 10,000 tons hot rolled and cold rolled S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades in stock each month. We can meet our customer's any quantity request. Based on these stock source, our advantage industry spread into steel process like : cutting ( any size and any shape ) drilling, welding, milling, machining and steel structure. We also have a high quality logistics team who make sure the fast delivery time and shipment. Anyway, if you want to find S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate/sheet supplier, S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate/sheet bar manufacturer, S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate/sheet bar exporter, please contact steel's sales team. We will give you the S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate competitive price, S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate good quality and best service from us.
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Retrieved Text: 5.1 Mechanical Weathering Rocks weather when they are exposed to surface conditions, which in most case are quite different from those at which they formed. The main processes of mechanical weathering include exfoliation, freeze-thaw, salt crystallization, and the effects of plant growth.
5.2 Chemical Weathering Chemical weathering takes place when minerals within rocks are not stable in their existing environment. Some of the important chemical weathering processes are hydrolysis of silicate minerals to form clay minerals, oxidation of iron in silicate and other minerals to form iron oxide minerals, and dissolution of calcite.
5.3 The Products of Weathering and Erosion The main products of weathering and erosion are grains of quartz (because quartz is resistant to chemical weathering), clay minerals, iron oxide minerals, rock fragments, and a wide range of ions in solution.
5.4 Weathering and the Formation of Soil Soil is a mixture of fine mineral fragments (including quartz and clay minerals), organic matter, and empty spaces that may be partially filled with water. Soil formation is controlled by climate (especially temperature and humidity), the nature of the parent material, the slope (because soil can’t accumulate on steep slopes), and the amount of time available. Typical soils have layers called horizons which form because of differences in the conditions with depth.
5.5 The Soils of Canada Canada has a range of soil types related to our unique conditions. The main types of soil form in forested and grassland regions, but there are extensive wetlands in Canada that produce organic soils, and large areas where soil development is poor because

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Retrieved Text: EvC Forum: How to make sand.
Author Topic: How to make sand.
I essentially agree with everything you say in that message.
So at the mouth of the Mississippi River why is there only quartz and clay and not garnet. The clays (as a mineral) are the result of chemical weathering, the garnet as well is gone, not because it wasn't hard, but because it isn't as resistant to chemical weathering as quartz.
I don't know to what degree garnet (and there are at least 6 different types of garnet) is more chemically stable than quartz. I suspect that garnet is still quite chemically stable.
I think a main reason quartz sand is so common is that it is a very abundant mineral in igneous and metamorphic rocks. Relative to quartz, garnet is a very minor mineral. So, even if it was both physically and chemically as stable as quartz, it would still be uncommon to find as sand.
Look up Bowen's Reaction Series. It shows you the pressure and temp minerals crystallize at, but it also shows you what minerals are less resistant to chemical weathering. The last mineral crystallizing at the lowest temp and pressure is quartz, and therefore the most resistant to chemical weathering at the surface.
It's referred to as the Goldich dissolution series. Yes, it is the inverse of the Bowen reaction series, but I think attributing chemical resistance to formation temperatures and especially pressure is a bit of an oversimplification. Bowen's series doesn't really have anything to do with pressure.

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Retrieved Text: Henan Huawei Aluminum Co.,Ltd Aluminum is specialized in the production of Aluminum Tread plate/checkered plate—also known as floor plate, diamond plate, or diamond tread plate—provides a durable, anti-slip surface for dock surfaces, vehicle running boards, truck toolboxes and more. Because it is highly resistant to weathering, corrosion, and chemicals, tread plate requires no maintenance or surface treatments.Available in 6061-T6 and 3003-H14 sizes. The 6061-T6 alloy has a dull mill or shiny finish and is harder and more durable, and the 3003-H14 has shiny bright finish, and is softer and more fordable.
NEXT：What is aluminum circle/disc and its applications?

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Rank: 19
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Retrieved Text: You are here:Home - FAQ - S355J0W weathering steel, S355J0W weathering steel test S355J0W weathering steel, S355J0W weathering steel test S355J0W weathering steel under EN 10155 standard, it is a kind of low alloy structural steel with 355 Mpa minimum yield.
S355J0W steel is a kind of corrosion resistance steels which standard by EN 10155. S mean S355J0W grade could be used in structural steel projects, 355 is the min yield strength. J0 ,J2 and K2 standard for the impact degree and energy in 0 temperature.
EN S355 J0W steel plate,S355 J0W steel plate, under EN 10155 standard, we can regard S355J0W steel plate as Steel Resistant to Atmospherical Corrosion S355 J0W steel plate is one mainly of Steel Resistant to Atmospherical Corrosion, S355J0W steel grade is a hot rolled products of structural steels in technical delivery conditions with improved atmospheric corrosion resistance.

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Rank: 20
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Retrieved Text: GB/T 4171 Q355GNH Corten steel plate has better corrosion resistance.GB-T 4171 ... China GB/T 4171 Q310GNH Weathering steel round ... price and factory; a558a steel ...Q415NH Weathering steel plate for better corrosion ... These elements change the basic properties of the original carbon steel. ... GB/T 4171-2008. Weathering Steel ...BBN is the China Iron and steel supplier/factory,offer GB T 4171 ... Cheaper GB/T 4171 Q295NH steel sheet price ... Weathering Steel Plate/Coil: Q295GNH: ...China Anti-Corrosion Steel Plate/Weather Resistant Steel Plate/Corten Steel Plate, Find details about China Weathering Steel Plate, Corrosion ... GB/T 4171 : Q235NH ...BBN steel a China steel factory,offer steel plate stock ... TB/T 1979 09CuPCrNi-A 05CuPCrNi GB/T 4171 ... Alloy steel EN10083-3 51CrV4 GB/T 3077 12Cr1MoV 20Cr ...Q295nh Steel, Wholesale Various High Quality Q295nh Steel Products from Global Q295nh Steel Suppliers and Q295nh Steel Factory,Importer,Exporter at Alibaba.China Atmospheric Corrosion Resistance SMA490ap Steel Sheet, Find details about China Sma490bp Weathering Steel, ...Bebon steel can supply Hot rolled GB/T1591 Q420A carbon alloy steel tube, ... GB/T 4171 Q345GNHLJ Weathering steel plate, ... Q295GNH Weathering Steel Plate ;... Find details about China Anti-Corrosion Steel Plate, Weathering Steel Plate from ... Weathering Steel Plate, Weathering Steel Sheet ... GB/T 4171 : Q235NH ...China A242 S355j2wp ASTM A588 Weathering Corten Steel Sheet, ... 10mm Thick Hot Rolled Anti-Corrosion Corten B Steel Plate for Building ... GB/T 4171: Q235NH ...China Hot Rolled Alloy Anti-Corrosion Weather Resistant Corten Steel Plate, Find details about China Weathering Steel Plate, Corrosion Resistant ... GB/T 4171 ...Corten Weather Resistant Anti Corrosion Steel Plate ...

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Rank: 21
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Retrieved Text: Atmospheric Corrosion Resistant Steel Plate Corten B , Find Complete Details about Atmospheric Corrosion Resistant Steel Plate Corten B,Steel Plate Corten B,Atmospheric Corrosion Resistant Steel Plate,Plate Corten B from Steel Sheets Supplier or Manufacturer-Chengdu Derbo Steel Co., Ltd.
ASTM A242 steel is a high strength low-alloy structural steel ASTM specification with improved atmospheric corrosion resistance. This specification is normally applicable to steel plates through one-half inch in thickness.See What Other Plate Collectors Have Already Discovered!Official ASTM Standards.
Cost of weathering steel astm a588 plate vs carbon steel ... astm a588 plate material is a kind of low alloy high strength structural weathering resistance steel, or corten steel, or atmosphere corrosion resistance steel. There is two grades they are ASTM A588 grade A, ASTM A588 grade B, ASTM A588 grade C, ASTM A588 grade K.
COR-TEN has served as weathering steel (atmospheric corrosion- resistant steel). Corten steel plate has successfully overcome rust, steel's most weakest. When exposed to the atmosphere without painting, corten steel begins to rust in the same way as ordinary steel.
A588 is available in steel plate and starts at 3/16 ... such as ASTM A588, A242, ...Jin Chao Yang can supply A242Type1 Weather Resistant Steel, corrosion resistant steel, ASTM A242, A242M-93a, S355K2G2W steel plates, welcome to inquiryASTM A242 specification is the ... Colorful steel.
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Retrieved Text: It is a copper chromium alloy steel – this alloy displays a greater level of resistance to atmospheric weathering when compared to other unalloyed steels.A588 Gr.C Weathering Resistant Steel Plate Corrosion Resistance BBN offer A588 Gr.C Weathering Resistant Steel Plate in China.
Atmospheric corrosion resistant steel ASTM A 588 Grade A. A588 Grade A atmospheric corrosion resistant HSLA steel is a high-strength low-alloy structural steel with up to a 50 ksi minimum yield point featuring atmospheric corrosion resistance.
BBN Steel mainly export ASME SA588 Grade A atmospheric corrosion resistant 8mm steel sheet size,Corten A, A588 Grade A, A588 Grade B, A588 Grade C, A588 Grade K,S235J0W, S355J0WP, 09CuPCrNi-A,S355J0W,Q355GNH, Q355NH, SPA-H,A242 Type 1, S355J0WP, S235J0W, Q460NH, Q295NH weather resistant steel plate stock for you,looking forward to our cooperation!

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Retrieved Text: Although most people think of saltwater when they think about tropical fish, there are many tropical fish that thrive in freshwater, too. If you're looking to create a freshwater aquarium, tropical fish can make it bright and vibrant. Knowing which rocks are best to put in the tank with these fish is important. Here's a look at what you need to know to avoid releasing harmful minerals into the water while still giving your fish rocks to swim around and make part of the habitat.
Slate is an ideal stone for freshwater aquariums because it doesn't release any chemicals into the water. It's pretty heavy, which means that if you plan to build a structure of any kind, you'll need an aquarium-quality sealant to keep it together. It's best to use it solely for tank-bottom decorations so that it can sit flat on the bottom of the tank. When you use it this way, the smooth texture of the slate surface provides an ideal environment for fish to nest and lay eggs..
Quartz stone makes a great addition for a freshwater tropical tank. The stone is inert, so it won't alter the tank chemistry at all. You can find it in many colors, which is ideal when you're putting it in a tropical tank because you can find colors that complement the fish you put into your tank. It's strong, stacks well and stays where you put it, so it's a good rock choice if you want to build any kind of stone structure in the tank.
Lava rock

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Retrieved Text: S355J2G2W steel in US, steel,Hot sell S355J2G2W steel in US, hot rolled steel plate stock in China,China S355J2G2W steel in US, hot rolled steel plate factory. Keeps more than 10,000 tons hot rolled and cold rolled S355J2G2W steel in US, hot rolled steel plate in stock each month. We can meet our customer's any quantity request. Based on these stock source, our advantage industry spread into steel process like : cutting ( any size and any shape ) drilling, welding, milling, machining and steel structure. We also have a high quality logistics team who make sure the fast delivery time and shipment. Anyway, if you want to find S355J2G2W steel in US, hot rolled steel plate plate/sheet supplier, S355J2G2W steel in US, hot rolled steel plate plate/sheet bar manufacturer, S355J2G2W steel in US, hot rolled steel plate plate/sheet bar exporter, please contact steel's sales team. We will give you the S355J2G2W steel in US, hot rolled steel plate plate competitive price, S355J2G2W steel in US, hot rolled steel plate plate good quality and best service from us.
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S355J2G2W steel is known as steel resistant to atmospheric corrosion and has been widely used in manufacturing and industries for its good performance in many aspects. As one of the most popular S355 J2G2W steel Chinese supplier, Bebon could offer

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Retrieved Text: ASTM A242 Type 4 weather resistant steel sheet, steel,Hot sell ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades stock in China,China ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades factory. Keeps more than 10,000 tons hot rolled and cold rolled ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades in stock each month. We can meet our customer's any quantity request. Based on these stock source, our advantage industry spread into steel process like : cutting ( any size and any shape ) drilling, welding, milling, machining and steel structure. We also have a high quality logistics team who make sure the fast delivery time and shipment. Anyway, if you want to find ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate/sheet supplier, ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate/sheet bar manufacturer, ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate/sheet bar exporter, please contact steel's sales team. We will give you the ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate competitive price, ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate good quality and best service from us.
A606 4 is considered weathering steel sheet with Bare Cold rolled steel is used as a less expensive option to A606 Type 4 such as ASTM A588, A242, Weather Resistant Steel Sheet, Weather Resistant Steel offers

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Rank: 26
Score: 48.685966
Retrieved Text: Bebon have Good Quality New Corten Weathering in stock and we also can provide Good Quality New Corten Weathering machining service . So if you need Good Quality New Corten Weathering price , Please Contact Us.
Weathering steel has been used for structural applications for over 50 years and has a good record for integrity and low maintenance. There are a number of equivalent products on the market such as Cor-Ten, PATINAX and European counterparts.
China Good Quality Low price Hot rolled corten steel plates is the main product of Henan Bebon Iron & Steel Co., Ltd. China Good Quality Low price Hot rolled corten steel plates is mainly used in automobile or in the construction industry.
Due to the high corrosion resistance of corten steel sheets, it normally takes from 1 to 2 years from a completely new steel sheet to the formation of a stable, dense, rust-red protective layer (50-100mic thick) in natural environments.
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Retrieved Text: Q460NH steel plate under China GB/T 4171 standard, it is a kind of weathering steel.Q460NH steel has good weldability and low temperature impact toughness, it suitable for architecture, artifacts such as weather resistance of weldments.Q415NH steel plate under China GB/T 4171, it is a kind of high tensile strength weathering steel.Q415NH steel plate tensile strength is 520-680 Mpa, Q415NH steel plate yield strength shall be above 415Mpa for the thickness equal and bellows 16mm.Any request for China GB/T 4171 Q460NH Steel Plate, Please Email: shi@hzzsteel.cn and Tel:0086-371-65652655 Inquiry If you have any request or doubts,Please send message to us,It will be checked for you on time.Weather Resistant Steel Plate,Weather Resistant Steel Plates,Weather Resistant Steel Sheets,Weather Resistant Steel Sheet. Steel Standard: corten, astm a588/a588m, asme sa588/sa588m ,en 10025-5, en 10155, tb/t 1979, gb/t 4171 …GB/T4171 Q550NH structural steel plate. GB / T4171 Q550NH structural steel plate is mainly used for vehicles, bridges, containers, construction or other structural parts and other structures, compared with high weathering steel, with good welding performance.GB / T4171 Q550NH steel plate is welded atmospheric corrosion resisting structural steel,GB / T4171 Q550NH steel plate …Jul 15, 2016 · The applicable equivalent ASTM specifications for weathering steel are ASTM A588, ASTM A242, ASTM A606-4, ASTM A847 and ASTM A709-50W, other standards JIS G3125, JIS G3114, EN10025 and GB/T4171. AGICO-ANSON STEEL supplies various products including, steel sheet, steel coil, steel plate, steel flats, …Gangsteel sell GB-T1591 Q345D Low alloy and high strength steel plate, heavy plate and wide, heavy plate, Which GB-T1591 Q460D Steel plate supp

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Rank: 28
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Retrieved Text: A588Gr. A is a corrosion resistant steel, also can be called weathering resistant steel or atmosphere corrosion resistant steel. A588Gr. A also is a high strength low alloy steel, so it is suitable for a lot of applications exposed the weather condition.
A588Gr. A steel is becoming more popular by roll formed product end-users. Its unique look and naturally oxidizing finish make it especially desirable for many architectural projects. A588Gr. A has increased resistance to atmospheric corrosion when compared to other steels. A588Gr. A resists the corrosive effects of rain, snow, ice, fog, and other meteorological conditions by forming a coating of dark brown oxidation over the metal, which inhibits deeper penetration and save the cost for painting or rust-prevention maintenance.
A588Gr. A Steel never completely stops rusting. The weathering process occurs after the panel come out. It eventually decreases and from that point on the finish acts as a protective coating for the base metal.
ASTM A588Gr. A is mainly used for constructions such as steel structures, bridges, tanks and containers, exhaust systems, vehicles and equipment constructions.
For more information about the A588Gr. A weather resistant steel or you would like to know the price , please contact us without hesitate.

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Retrieved Text: Grand Cru Frankstein is of eight Grands Crus which lie on granite, the rock that the Vosges mountain range is made up of. Granite is hard and resistant to weathering, typically with thin, sandy soils that provide fast heating during the day, rapid cooling at night and that are well drained. Here, a skilled grower can choose to either create voluptuous, easy-going wines with character of fruit salad, or firm and crystalline wines in a more restrained style, without hints of botrytis. Florian Beck-Hartweg has, with great skill and dedication, chosen the latter course.

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======= Instance Index 1378 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are RJ's or Tony's ):

Different types of rocks weather at different rates. More resistant types of rocks will remain longer.


RJ diamond is more resistant to weathering while Tony has some sandstone which is less resistant to weathering. Whose rock will likely not last as long RJ's or Tony's?

Target Text: Tony's

#### Retrieved Documents ####

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Retrieved Text: Often proceeding at small, subtle and slow rates, weathering fragments or dissolves rock: a hugely influential geological process that commonly sets the stage for erosion and provides the critical “parent material” for developing soils. The type of rock certainly influences the kind, degree and pace of weathering it will be vulnerable to, although many other factors come into play – not least the surrounding climate.
Weathering breaks down rock through mechanical or chemical processes. Different types of rock have different resistance to weathering, but many other factors besides basic mineral content influence weathering rates, including climate.
Weathering takes apart rock by mechanical disintegration or chemical decomposition. Mechanical (or physical) weathering refers to rock fragmentation by such forces as ice- or salt-wedging and the unloading of pressure on rocks formed far underground and then exposed at the Earth’s surface. Chemical weathering, meanwhile, covers processes that weather rock through chemical reactions, as when minerals in rocks are dissolved or replaced through exposure to air or water.
The relative resistance or “toughness” of a given rock to weathering certainly depends partly on what kind of rock it is. That’s because rock type is determined by the composition and proportion of the constituent minerals, and different minerals vary in how they stand up to weathering. Quartz, for example, is more resistant that micas, which in turn are more resistant than feldspars. But you can’t really make a general ranking of rock types by resistance to weathering because of all the other variables involved.
Not all rocks within a given type, such as granite and

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Retrieved Text: A mesa is an elevated section of land with flat top and can be found in various countries around the world.
Grand Mesa in Colorado, USA, is the largest mesa in the world.
A mesa is a geographical feature characterized by an elevated section of land with a flat top, whose sides form cliffs or gentle slopes. The elevated land can rise for thousands of feet above the surrounding area to form what is referred to as table mountain or table hill. The term “mesa” is a Spanish word which means “table” in English. Mesas typically exist in arid environments and can be found in the western United States, South Africa, Spain, and Australia. Grand Mesa, a flat-topped mountain in Colorado, is the largest mesa is the world.
A mesa is usually formed when a horizontal stratification of rock is pushed upwards by tectonic forces. Erosion and weathering then act on these rocks, and the weaker layers of rocks are eroded away, leaving behind the more resistant rocks which become elevated above their surroundings in a process known as differential erosion. These erosion resistant rocks form the distinct flat-top that characterize a mesa. Some common rocks which make up a mesa are basalt, sandstone, chert, conglomerate, lava flows, and spills. All of these types of rock are highly resistant to weathering and erosion. The mesa formation process is very lengthy, and can take several million years. The variation in rock types during the formation of a mesa also affects the steepness of the sides of the mountain. More resistant

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Retrieved Text: Sandstone is a clastic sedimentary rock that is made up of cemented sand grains usually quartz and has a gritty feel to it.
Red color is usually given to the rock by iron oxide hematite. It usually is associated with current or former mountain ranges because mountain-building is the process that is responsible for the deep burial and associated metamorphism that transforms sandstone to quartzite.
It is available in a range of neutral colors that many people prefer. This is a green variety of quartzite. It tolerates weathering well because its main constituent quartz is very resistant to both physical and chemical disintegration.
Its hardness and toughness cause heavy wear on crushers, screens, truck beds, cutting tools, loaders, tires, tracks, drill bits, and other equipment. John, used here under a Creative Commons license. Tumbled Stones. This is why quartzite is so often the rock found at the crests of mountain ranges and covering their flanks as a litter of scree.
Width of sample 19 cm. The photo shows a quartzite arrowhead found in Alabama. In the dimension stone industry, some quartzite is sold as "granite" because in that industry, any hard silicate rock is often called "granite.
Sandstone is a sedimentary rock, a type of rock that is made through solidification of. Width of sample 13 cm. E-mail C. Some quartzites are still similar to sandstones, only more strongly held together, while others are completely recrystallized so that all the features like fossils or original texture are obliterated and grain boundaries have disappeared.
Aventurine can be pink or red when stained with

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Retrieved Text: (Phys.org) —A team of researchers with members from facilities in the Czech Republic and one from the U.S. has discovered the mechanism by which unique sandstone landforms take shape. In their paper published in Nature Geoscience, the team describes how their studies of sandstone in their lab led to insights about how both gravity and erosion contribute to the creation of such unique structures as Delicate Arch at Arches National Park in Utah. Chris Paola of the University of Minnesota offers a News & Views piece on the research done by the team in the same journal issue.
Curious as to the real mechanism by which sandstone landforms take shape, the researchers took several samples into their lab and subjected them to intense scrutiny—after cutting the samples into cubes, they used pressure plates to simulate the loads of real structures while also subjecting them to simulated wind and rain. As the cubes were deformed, close inspection revealed that in the parts of the sandstone subjected to direct pressure (simulated gravity) individual grains tended to lock together creating sections of stone that were more resilient to wind and rain. That led to the creation of pillars within the sandstone that stood strong as the grains around them were swept away. As more free grains were swept away, more pressure was exerted on the column causing the grains in them to lock even tighter.
The team found that when pressure was applied from above to different parts of a cube, and artificial cracks and other perturbations were also introduced to

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Retrieved Text: Add some color to that boring wall in your home with this vibrant, premium wrapped canvas print from Zazzle! Made from an additive-free cotton-poly blend, it’s long lasting and fade resistant – a gallery quality print made in Reno, Nevada. Available in several sizes.
I recently visited the Big South Fork National River & Recreation Area, which encompasses 125,000 acres of the Cumberland Plateau – in both Kentucky and Tennessee – and boasts miles of scenic gorges and sandstone bluffs.
With many sights to see, I decided to hike the Twin Arches, described as “the most impressive rock arches in the eastern United States”. The North Arch has a clearance of 51 feet, a span of 93 feet and its top deck is 62 feet high, while the South Arch has a clearance of 70 feet, a span of 135 feet and its top deck is 103 feet high.
Weaker layers of sandstone form the base of the nearly vertical walls of this narrow ridge. The weathering of these erosion-susceptible layers caused sections of the wall to fall away, forming shallow rock shelters on both sides of the ridge.
The collapse and shelter enlarging process continued until two “windows” in the narrow ridge were formed. This opening enlarged until it reached the stronger and more erosion-resistant sandstone layer of rim rock that caps the Twin Arches.
A cave was situated under one end of the South Arch, so I entered to discover that there was an exit at the back, albeit a narrow passage at approx. 18″ wide. Footprint-impressions in the

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Retrieved Text: Both blue stone and granite are popular building materials prized for their durability and versatility. Both stones are often seen in large buildings and architectural and landscaping elements.
Granite is a popular, durable building stone.
Blue stone is used for a wide variety of purposes, including bridges, driveways, walls, steps, landings and indoor projects. However, it is most commonly employed to build outdoor paving areas, like walkways and patios, according to The Stone Yard.
Granite is also versatile, but is especially used in large building projects for structural stones, wall cladding, roofing, flooring and interior and exterior decorating.
Blue stone is a specific type of fine-grained sandstone called arkosic sandstone that appears blue when it has just been broken or is wetted. However, it exists in a variety of colors and is also known as feldspathic sandstone.
Granite is an igneous rock primarily composed of feldspar, quartz and at least one dark mineral. It was named for its granular texture.
While blue stone is durable and crack-resistant, it is most valued for its ability to easily separate into almost any size slab, according to The Stone Yard.
Granite is the hardest of all building stones, homogeneous in texture, durable, resists weathering, has a high load bearing capacity, crushing strength and abrasive strength, cuts and shapes without secondary flaws, takes a mirror polish and is stain resistant.
What Is Uba Tuba Granite?

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Retrieved Text: Sandstone is a sedimentary rock composed of mostly quartz compressed and cemented together. The cementing agents are the materials that hold the sandstone together. The composition of the stone and the cementing agent used will determine the strength, durability and weather-resistant properties of the sandstone.
Silica cement, also called quartz cement, creates the strongest and most durable type of sandstone used for building. The cement is a result of the quartz grains overgrowing and expanding the crystallized forms until it runs into another quartz crystal. This type of sandstone typically forms in environments that have high-energy currents, such as beaches, marine bars and desert dunes.
Calcite cement is the most common type of cement found in sandstone. The calcite cement typically forms in patches and does not fill all the gaps within the stone. This makes calcite cement sandstone very porous. Calcite is also soluble in wate, which can erode away the cement making the stone even more porous.
Another common cementing agent in sandstone is iron oxide, also called hematite cement. The iron present in the cement will give the sandstone a distinctive red color. According to the Stone Care Techniques website, iron oxide cemented sandstone weather well in dry climates and become harder and stronger, resisting weathering and deterioration.
Sandstone also has other cementing agents that occur in less common forms. These cementing agents include pyrite, barite and gypsum. These cementing agents form crystals between the particles of the stone. These cements produce a much softer type of sandstone with the particles able to be rubbed off the

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Retrieved Text: Indian sandstone is a popular choice for the Irish market as the stone is highly resistant to the effects of Irish weathering. At Forge Paving Centre, we carry a wide range of Indian sandstone in a variety of colours including: Mint Fossil, Rippon, Raveena, Mint Venetian, Camel Dust, Raj Green and Kandla Grey.
Sandstone Circles also available in select colours..

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Score: 54.020294
Retrieved Text: Corten steel coils are in stock in ... patina after exposure to the weather. A588 plate is in stock at 96 ...Find great deals on eBay for weathering steel. ... HO Custom Weathered MDC ATSF Santa Fe 60' bulkhead flat Steel mill Plate ... 96511-3-02 Weather Guard Steel ...You Source for weathering steel, coil, sheet, plate ... is Cor-ten ®.
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EN 10155 S235J0W anti weathering corrosion 8mm steel sheet resistant to atmospheric effects; ... Q BQB 340 B400NQR1 atmospheric corrosion resistant 8mm steel plate; ... Q B QB 340 B460N QR atmospheric corrosion resistant 16mm steel plate for sale .
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A588GrA general 8mm ~ 200mm thick, A588 series high weathering steel bridge structures including A588GrA, A588GrB so on. Such steel by Cu, P, Cr, Ni and other alloying the metal substrate surface to form a protective layer, which has a high resistance to atmospheric corrosion. Read more; a588b Weather Resistant Steel Plate.
B400NQR1 Weathering steel sheet Material, B400NQR1 steel . B400NQR1 Weathering steel sheet

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Rank: 9
Score: 53.010452
Retrieved Text: Shop Over 1 Million Items At Zoro, 7,000+ Trusted Brands, Hassle Free Returns.S235J2W steel is a structural weathering steel ... the steel from corrosion. S235J2W steel plate, EN 10155 ... standard deform reinforcing steel bar sizes;EN 10155 standard specification used for Steel Resistant to Atmospherical Corrosion, S355J2G1W,S355J2G2W,S355K2G1W,S366K2G2W. BS EN 10155 Technical deS355J0W weathering steel under EN 10155 standard, ... S235J2W steel plate,low alloy weld-ability ... A588 Gr.C Weathering Resistant Steel Plate Corrosion Resistance ;Standard: ASTM, JIS, BS, GB, EN ... Corten B steel plate Heat Treatment: ... A588 Gr.C Weathering Resistant Steel Plate Corrosion Resistance ;low allory steel stock price and supplier,BBN steel offer EN 10155 S235J0W Weathering Corrosion ... s235j2W steel plate; ... Anti Corrosion Weather steel plate ;... Thickness 8mm-300mm, Width: 1500-4020mm, ... Home > Products > Weather resistant steel plate > EN 10155 Weathering steel > EN 10155 Weathering steelEN S355J2G1W Introduction S355J2G2W Steel sheet adopts standard EN100155, as a structural weathering steel with super property because of chemical compositions, Chromium, Nickle, Copper ect. anti-corrosion alloying elements.... corrosion resistance udder EN 10025-2 standard. ... Mpa,and the EN10025-5 S235J2W tensile strength for the ... weathering steel, and anti-corrosion ...EN10155 Standard S355J2W steel plate ... Weather resistant steel plate > EN 10155 Weathering steel ... corrosion of the steel. S355J2G1W EN 10155 ...Aakash steel is leading suppliers and manufacturers of Corten Steel Plate..aakash steel ... own atmospheric corrosion resistant weathering ... EN 10155, S355K2G1W ...Weather Resistant Steel Plate( Weathering Steel ... Ni and other anti- corrosion elements to common steel, ... EN 10155 S355K2G2W Weather

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Rank: 10
Score: 52.59253
Retrieved Text: EN S355J2G1W anti weathering corrosion steel sheet, steel,Hot sell EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades stock in China,China EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades factory. Keeps more than 10,000 tons hot rolled and cold rolled EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades in stock each month. We can meet our customer's any quantity request. Based on these stock source, our advantage industry spread into steel process like : cutting ( any size and any shape ) drilling, welding, milling, machining and steel structure. We also have a high quality logistics team who make sure the fast delivery time and shipment. Anyway, if you want to find EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate/sheet supplier, EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate/sheet bar manufacturer, EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate/sheet bar exporter, please contact steel's sales team. We will give you the EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate competitive price, EN S355J2G1W anti weathering corrosion steel sheet, pressure vessel steel plate grades plate good quality and best service from us.
EN S355J2G1W Introduction S355J2G2W Steel sheet adopts standard EN100155, as a structural weathering steel with super property because of chemical compositions, Chromium, Nickle, Copper ect. anti corrosion alloying elements.
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Rank: 11
Score: 52.512535
Retrieved Text: S355K2G2W anti weathering corrosion steel plate, steel,Hot sell S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades stock in China,China S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades factory. Keeps more than 10,000 tons hot rolled and cold rolled S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades in stock each month. We can meet our customer's any quantity request. Based on these stock source, our advantage industry spread into steel process like : cutting ( any size and any shape ) drilling, welding, milling, machining and steel structure. We also have a high quality logistics team who make sure the fast delivery time and shipment. Anyway, if you want to find S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate/sheet supplier, S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate/sheet bar manufacturer, S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate/sheet bar exporter, please contact steel's sales team. We will give you the S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate competitive price, S355K2G2W anti weathering corrosion steel plate, pressure vessel steel plate grades plate good quality and best service from us.
EN 10155 S355K2G2W Anti Corrosion Weather Weathering mild Due to its good anti corrosion property, Corten A steel plate has EN 10155. S235J2W; S355J0WP Corten B weathering steel plate application S355K2G2W weathering corten steel plate we offer high quality, own atmospheric corrosion resistant weathering steels.
Weathering, Corrosion Resistant Steel Plate;BBN steel offer all kinds of

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Rank: 12
Score: 52.327045
Retrieved Text: we promise we can offer you the qualified sa588 grade b corten steel resistant to atmospheric effects at the competitive price and rapid delivery time.We can produce as our customer's requirement.We keep many sa588 grade b corten steel resistant to atmospheric effects stock in our warehouse, So hereby, we sincerely hope you join us, let's join hands to make you be the No.1 in your local steel market.
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we can corten A,corten B,spa-H steel,sa588 corrosion resisting steel,s355J0WP weathering steel products,if you need corten A,corten B,spa-H,sa588,s355J0WP steel,can contact us. ... Improved atmospheric corrosion resistance steel means weathering steel or atmosphere corrosion resistance steel. The material No.
ASME SA588/SA588M:SA588 Grade A,SA588 Grade B,SA588 Grade C,SA588 Grade K, ... EN10034, BS 4-1, BS4360 Hot Rolled Steel Beam, ... BS 4360 WR 50 A steel is a structural weathering steel which is also referred to as atmospheric corrosion resistant steel.
Weather Resistant Anti Corrosion Steel Plate ..... their own atmospheric corrosion resistant weathering ... sheet,mild steel sheet ... Grade A, SA588 Grade B, SA588 Grade C. Corten Steel Plate ...Anti- corrosion steel plate supplier. Steel for resistant to atmospheric corrosion is also called weathering resistant steel.
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Rank: 13
Score: 52.120293
Retrieved Text: Find Information Now. Browse Top Results and Explore Answers Now!Search for Weathering. Look Up Quick Answers Now!Grade: ASME SA588 Grade B Type : Steel sheet Steel ... ASME SA588 Grade C Anti-corrosion ... Environmentalists often prefer weathering steel for it eliminates ...Grade: ASME SA588 Grade B Type : Steel sheet Steel Plate Standard : ASME Specification: Thickness: 4-200mm Width: 1500mm-3000mm Length: 6000mm-12000mmMild Steel Sheet ASME SA588 GrA Weathering Corrosion Resistance Anti Corrosion Weather steel platea588 grade b steel plate . ... A588GrB steel plates with the thickness form 8mm~200mm are used as high weathering bridge ... ASME SA588 Grade B Corten Plate; ASME ...own atmospheric corrosion resistant weathering steels. ... Corten Steel Plate Grade and Specification ... ASME SA588 Grade B Corten Plate... offer SA588 Grade C mild anti weathering corrosion steel ... Steel Sheet SA588 Grade C mild anti ... ASME SA588/SA588M:SA588 Grade A,SA588 Grade B,SA588 ...Corten steel, Weathering steel, Weathering resistant steel, atmosphere corrosion resistance steel SA588 grade A,SA588 grade B, SA588 grade C,SA588 grade KASTM A588 material is a kind of low alloy high strength structural weathering resistance steel,or corten steel,or atmosphere corrosion resistance steel.There is two grades they are ASTM A588 grade A,ASTM A588 grade B,ASTM A588 grade C1.1 This specification covers high ... corrosion resistance of this steel in most environments is ... Rolled Structural Steel Bars, Plates, Shapes, and Sheet ...Weathering steel has anti-rust, so that components corrosion-resistant life.The main grade ... Weathering resistant steel. Weathering steel has ... SA588 Gr.B. Corten B.SA588 grade C steel under ASME ... corrosion

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Rank: 14
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Retrieved Text: 5.1 Mechanical Weathering Rocks weather when they are exposed to surface conditions, which in most case are quite different from those at which they formed. The main processes of mechanical weathering include exfoliation, freeze-thaw, salt crystallization, and the effects of plant growth.
5.2 Chemical Weathering Chemical weathering takes place when minerals within rocks are not stable in their existing environment. Some of the important chemical weathering processes are hydrolysis of silicate minerals to form clay minerals, oxidation of iron in silicate and other minerals to form iron oxide minerals, and dissolution of calcite.
5.3 The Products of Weathering and Erosion The main products of weathering and erosion are grains of quartz (because quartz is resistant to chemical weathering), clay minerals, iron oxide minerals, rock fragments, and a wide range of ions in solution.
5.4 Weathering and the Formation of Soil Soil is a mixture of fine mineral fragments (including quartz and clay minerals), organic matter, and empty spaces that may be partially filled with water. Soil formation is controlled by climate (especially temperature and humidity), the nature of the parent material, the slope (because soil can’t accumulate on steep slopes), and the amount of time available. Typical soils have layers called horizons which form because of differences in the conditions with depth.
5.5 The Soils of Canada Canada has a range of soil types related to our unique conditions. The main types of soil form in forested and grassland regions, but there are extensive wetlands in Canada that produce organic soils, and large areas where soil development is poor because

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Rank: 15
Score: 51.07185
Retrieved Text: factory price spa-h corten steel plate. Product Description: Corten steel plate is a steel that Weather resistant structural steel. The anticorrosive properties of weather resistant steel are better than those of other structural steels in many applications.
Ms sheet metal corten steel SPA-H weather resistant steel : Corten steel plate is a steel that Weather resistant structural steel. The anticorrosive properties of weather resistant steel are better than those of other structural steels in many applications.
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Rank: 16
Score: 50.91375
Retrieved Text: China Q460 Q550 Q690 Low Alloy High Strength Steel Plate, ... BS4360 Grade: 12Mn 16Mn ... JIS 3125 SPA-H Hot Rolled Corten Weathering Steel Plate.
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Rank: 17
Score: 50.620987
Retrieved Text: EvC Forum: How to make sand.
Author Topic: How to make sand.
I essentially agree with everything you say in that message.
So at the mouth of the Mississippi River why is there only quartz and clay and not garnet. The clays (as a mineral) are the result of chemical weathering, the garnet as well is gone, not because it wasn't hard, but because it isn't as resistant to chemical weathering as quartz.
I don't know to what degree garnet (and there are at least 6 different types of garnet) is more chemically stable than quartz. I suspect that garnet is still quite chemically stable.
I think a main reason quartz sand is so common is that it is a very abundant mineral in igneous and metamorphic rocks. Relative to quartz, garnet is a very minor mineral. So, even if it was both physically and chemically as stable as quartz, it would still be uncommon to find as sand.
Look up Bowen's Reaction Series. It shows you the pressure and temp minerals crystallize at, but it also shows you what minerals are less resistant to chemical weathering. The last mineral crystallizing at the lowest temp and pressure is quartz, and therefore the most resistant to chemical weathering at the surface.
It's referred to as the Goldich dissolution series. Yes, it is the inverse of the Bowen reaction series, but I think attributing chemical resistance to formation temperatures and especially pressure is a bit of an oversimplification. Bowen's series doesn't really have anything to do with pressure.

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Rank: 18
Score: 50.142822
Retrieved Text: Henan Huawei Aluminum Co.,Ltd Aluminum is specialized in the production of Aluminum Tread plate/checkered plate—also known as floor plate, diamond plate, or diamond tread plate—provides a durable, anti-slip surface for dock surfaces, vehicle running boards, truck toolboxes and more. Because it is highly resistant to weathering, corrosion, and chemicals, tread plate requires no maintenance or surface treatments.Available in 6061-T6 and 3003-H14 sizes. The 6061-T6 alloy has a dull mill or shiny finish and is harder and more durable, and the 3003-H14 has shiny bright finish, and is softer and more fordable.
NEXT：What is aluminum circle/disc and its applications?

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Rank: 19
Score: 50.11181
Retrieved Text: You are here:Home - FAQ - S355J0W weathering steel, S355J0W weathering steel test S355J0W weathering steel, S355J0W weathering steel test S355J0W weathering steel under EN 10155 standard, it is a kind of low alloy structural steel with 355 Mpa minimum yield.
S355J0W steel is a kind of corrosion resistance steels which standard by EN 10155. S mean S355J0W grade could be used in structural steel projects, 355 is the min yield strength. J0 ,J2 and K2 standard for the impact degree and energy in 0 temperature.
EN S355 J0W steel plate,S355 J0W steel plate, under EN 10155 standard, we can regard S355J0W steel plate as Steel Resistant to Atmospherical Corrosion S355 J0W steel plate is one mainly of Steel Resistant to Atmospherical Corrosion, S355J0W steel grade is a hot rolled products of structural steels in technical delivery conditions with improved atmospheric corrosion resistance.

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Rank: 20
Score: 50.015446
Retrieved Text: GB/T 4171 Q355GNH Corten steel plate has better corrosion resistance.GB-T 4171 ... China GB/T 4171 Q310GNH Weathering steel round ... price and factory; a558a steel ...Q415NH Weathering steel plate for better corrosion ... These elements change the basic properties of the original carbon steel. ... GB/T 4171-2008. Weathering Steel ...BBN is the China Iron and steel supplier/factory,offer GB T 4171 ... Cheaper GB/T 4171 Q295NH steel sheet price ... Weathering Steel Plate/Coil: Q295GNH: ...China Anti-Corrosion Steel Plate/Weather Resistant Steel Plate/Corten Steel Plate, Find details about China Weathering Steel Plate, Corrosion ... GB/T 4171 : Q235NH ...BBN steel a China steel factory,offer steel plate stock ... TB/T 1979 09CuPCrNi-A 05CuPCrNi GB/T 4171 ... Alloy steel EN10083-3 51CrV4 GB/T 3077 12Cr1MoV 20Cr ...Q295nh Steel, Wholesale Various High Quality Q295nh Steel Products from Global Q295nh Steel Suppliers and Q295nh Steel Factory,Importer,Exporter at Alibaba.China Atmospheric Corrosion Resistance SMA490ap Steel Sheet, Find details about China Sma490bp Weathering Steel, ...Bebon steel can supply Hot rolled GB/T1591 Q420A carbon alloy steel tube, ... GB/T 4171 Q345GNHLJ Weathering steel plate, ... Q295GNH Weathering Steel Plate ;... Find details about China Anti-Corrosion Steel Plate, Weathering Steel Plate from ... Weathering Steel Plate, Weathering Steel Sheet ... GB/T 4171 : Q235NH ...China A242 S355j2wp ASTM A588 Weathering Corten Steel Sheet, ... 10mm Thick Hot Rolled Anti-Corrosion Corten B Steel Plate for Building ... GB/T 4171: Q235NH ...China Hot Rolled Alloy Anti-Corrosion Weather Resistant Corten Steel Plate, Find details about China Weathering Steel Plate, Corrosion Resistant ... GB/T 4171 ...Corten Weather Resistant Anti Corrosion Steel Plate ...

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Rank: 21
Score: 49.88088
Retrieved Text: Atmospheric Corrosion Resistant Steel Plate Corten B , Find Complete Details about Atmospheric Corrosion Resistant Steel Plate Corten B,Steel Plate Corten B,Atmospheric Corrosion Resistant Steel Plate,Plate Corten B from Steel Sheets Supplier or Manufacturer-Chengdu Derbo Steel Co., Ltd.
ASTM A242 steel is a high strength low-alloy structural steel ASTM specification with improved atmospheric corrosion resistance. This specification is normally applicable to steel plates through one-half inch in thickness.See What Other Plate Collectors Have Already Discovered!Official ASTM Standards.
Cost of weathering steel astm a588 plate vs carbon steel ... astm a588 plate material is a kind of low alloy high strength structural weathering resistance steel, or corten steel, or atmosphere corrosion resistance steel. There is two grades they are ASTM A588 grade A, ASTM A588 grade B, ASTM A588 grade C, ASTM A588 grade K.
COR-TEN has served as weathering steel (atmospheric corrosion- resistant steel). Corten steel plate has successfully overcome rust, steel's most weakest. When exposed to the atmosphere without painting, corten steel begins to rust in the same way as ordinary steel.
A588 is available in steel plate and starts at 3/16 ... such as ASTM A588, A242, ...Jin Chao Yang can supply A242Type1 Weather Resistant Steel, corrosion resistant steel, ASTM A242, A242M-93a, S355K2G2W steel plates, welcome to inquiryASTM A242 specification is the ... Colorful steel.
BBN Steel can provide ASTM A242 Type 2 atmospheric corrosion resistant 4mm steel plate equivalent,Corten A, A588 Grade A, A588 Grade B, A588 Grade C, A588 Grade K,S235J0W, S355J0WP, 09CuPCrNi-A,S355J0W,Q355GNH, Q355NH, SPA-H,A242 Type 1, S355J0WP, S235J0W, Q460NH, Q295NH weather resistant steel plate stock for

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Rank: 22
Score: 49.684345
Retrieved Text: It is a copper chromium alloy steel – this alloy displays a greater level of resistance to atmospheric weathering when compared to other unalloyed steels.A588 Gr.C Weathering Resistant Steel Plate Corrosion Resistance BBN offer A588 Gr.C Weathering Resistant Steel Plate in China.
Atmospheric corrosion resistant steel ASTM A 588 Grade A. A588 Grade A atmospheric corrosion resistant HSLA steel is a high-strength low-alloy structural steel with up to a 50 ksi minimum yield point featuring atmospheric corrosion resistance.
BBN Steel mainly export ASME SA588 Grade A atmospheric corrosion resistant 8mm steel sheet size,Corten A, A588 Grade A, A588 Grade B, A588 Grade C, A588 Grade K,S235J0W, S355J0WP, 09CuPCrNi-A,S355J0W,Q355GNH, Q355NH, SPA-H,A242 Type 1, S355J0WP, S235J0W, Q460NH, Q295NH weather resistant steel plate stock for you,looking forward to our cooperation!

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Rank: 23
Score: 49.216114
Retrieved Text: Although most people think of saltwater when they think about tropical fish, there are many tropical fish that thrive in freshwater, too. If you're looking to create a freshwater aquarium, tropical fish can make it bright and vibrant. Knowing which rocks are best to put in the tank with these fish is important. Here's a look at what you need to know to avoid releasing harmful minerals into the water while still giving your fish rocks to swim around and make part of the habitat.
Slate is an ideal stone for freshwater aquariums because it doesn't release any chemicals into the water. It's pretty heavy, which means that if you plan to build a structure of any kind, you'll need an aquarium-quality sealant to keep it together. It's best to use it solely for tank-bottom decorations so that it can sit flat on the bottom of the tank. When you use it this way, the smooth texture of the slate surface provides an ideal environment for fish to nest and lay eggs..
Quartz stone makes a great addition for a freshwater tropical tank. The stone is inert, so it won't alter the tank chemistry at all. You can find it in many colors, which is ideal when you're putting it in a tropical tank because you can find colors that complement the fish you put into your tank. It's strong, stacks well and stays where you put it, so it's a good rock choice if you want to build any kind of stone structure in the tank.
Lava rock

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Rank: 24
Score: 49.03178
Retrieved Text: S355J2G2W steel in US, steel,Hot sell S355J2G2W steel in US, hot rolled steel plate stock in China,China S355J2G2W steel in US, hot rolled steel plate factory. Keeps more than 10,000 tons hot rolled and cold rolled S355J2G2W steel in US, hot rolled steel plate in stock each month. We can meet our customer's any quantity request. Based on these stock source, our advantage industry spread into steel process like : cutting ( any size and any shape ) drilling, welding, milling, machining and steel structure. We also have a high quality logistics team who make sure the fast delivery time and shipment. Anyway, if you want to find S355J2G2W steel in US, hot rolled steel plate plate/sheet supplier, S355J2G2W steel in US, hot rolled steel plate plate/sheet bar manufacturer, S355J2G2W steel in US, hot rolled steel plate plate/sheet bar exporter, please contact steel's sales team. We will give you the S355J2G2W steel in US, hot rolled steel plate plate competitive price, S355J2G2W steel in US, hot rolled steel plate plate good quality and best service from us.
A wide variety of s355j2g2w corten steel plate options are available to you, There are 34 s355j2g2w corten steel plate suppliers, mainly located in Asia. The top supplying country is China (Mainland), which supply 100% of s355j2g2w corten steel plate respectively.
S355J2G2W steel is known as steel resistant to atmospheric corrosion and has been widely used in manufacturing and industries for its good performance in many aspects. As one of the most popular S355 J2G2W steel Chinese supplier, Bebon could offer

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Rank: 25
Score: 48.90748
Retrieved Text: ASTM A242 Type 4 weather resistant steel sheet, steel,Hot sell ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades stock in China,China ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades factory. Keeps more than 10,000 tons hot rolled and cold rolled ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades in stock each month. We can meet our customer's any quantity request. Based on these stock source, our advantage industry spread into steel process like : cutting ( any size and any shape ) drilling, welding, milling, machining and steel structure. We also have a high quality logistics team who make sure the fast delivery time and shipment. Anyway, if you want to find ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate/sheet supplier, ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate/sheet bar manufacturer, ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate/sheet bar exporter, please contact steel's sales team. We will give you the ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate competitive price, ASTM A242 Type 4 weather resistant steel sheet, pressure vessel steel plate grades plate good quality and best service from us.
A606 4 is considered weathering steel sheet with Bare Cold rolled steel is used as a less expensive option to A606 Type 4 such as ASTM A588, A242, Weather Resistant Steel Sheet, Weather Resistant Steel offers

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Rank: 26
Score: 48.685966
Retrieved Text: Bebon have Good Quality New Corten Weathering in stock and we also can provide Good Quality New Corten Weathering machining service . So if you need Good Quality New Corten Weathering price , Please Contact Us.
Weathering steel has been used for structural applications for over 50 years and has a good record for integrity and low maintenance. There are a number of equivalent products on the market such as Cor-Ten, PATINAX and European counterparts.
China Good Quality Low price Hot rolled corten steel plates is the main product of Henan Bebon Iron & Steel Co., Ltd. China Good Quality Low price Hot rolled corten steel plates is mainly used in automobile or in the construction industry.
Due to the high corrosion resistance of corten steel sheets, it normally takes from 1 to 2 years from a completely new steel sheet to the formation of a stable, dense, rust-red protective layer (50-100mic thick) in natural environments.
Prime Corten Sheet Metal Prices, China Good Quality Corten Steel Plate, Weathering Resistant Steel Coil manufacturer / supplier in China, offering Corten a Weathering Resistant Steel, Cold Rolled 2b Finish 4X8 SUS304 Stainless Steel Sheet Plate, Tisco 2b/Hl/No. 4/Ba Finish AISI SUS430 Inox Stainless Steel Sheet and so on.
Corten Plate, Corten Steel Plate, Corten Steel Sheet manufacturer / supplier in China, offering High Quality Weathering Corten Steel Plate 09cupcrni-a with Design Services, Good Quality Material N2 N4 Medical Nickel Pipe, Uns N06455 N10276 Alloy Nickel Tube and so on.

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Rank: 27
Score: 48.54343
Retrieved Text: Q460NH steel plate under China GB/T 4171 standard, it is a kind of weathering steel.Q460NH steel has good weldability and low temperature impact toughness, it suitable for architecture, artifacts such as weather resistance of weldments.Q415NH steel plate under China GB/T 4171, it is a kind of high tensile strength weathering steel.Q415NH steel plate tensile strength is 520-680 Mpa, Q415NH steel plate yield strength shall be above 415Mpa for the thickness equal and bellows 16mm.Any request for China GB/T 4171 Q460NH Steel Plate, Please Email: shi@hzzsteel.cn and Tel:0086-371-65652655 Inquiry If you have any request or doubts,Please send message to us,It will be checked for you on time.Weather Resistant Steel Plate,Weather Resistant Steel Plates,Weather Resistant Steel Sheets,Weather Resistant Steel Sheet. Steel Standard: corten, astm a588/a588m, asme sa588/sa588m ,en 10025-5, en 10155, tb/t 1979, gb/t 4171 …GB/T4171 Q550NH structural steel plate. GB / T4171 Q550NH structural steel plate is mainly used for vehicles, bridges, containers, construction or other structural parts and other structures, compared with high weathering steel, with good welding performance.GB / T4171 Q550NH steel plate is welded atmospheric corrosion resisting structural steel,GB / T4171 Q550NH steel plate …Jul 15, 2016 · The applicable equivalent ASTM specifications for weathering steel are ASTM A588, ASTM A242, ASTM A606-4, ASTM A847 and ASTM A709-50W, other standards JIS G3125, JIS G3114, EN10025 and GB/T4171. AGICO-ANSON STEEL supplies various products including, steel sheet, steel coil, steel plate, steel flats, …Gangsteel sell GB-T1591 Q345D Low alloy and high strength steel plate, heavy plate and wide, heavy plate, Which GB-T1591 Q460D Steel plate supp

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Rank: 28
Score: 48.436066
Retrieved Text: A588Gr. A is a corrosion resistant steel, also can be called weathering resistant steel or atmosphere corrosion resistant steel. A588Gr. A also is a high strength low alloy steel, so it is suitable for a lot of applications exposed the weather condition.
A588Gr. A steel is becoming more popular by roll formed product end-users. Its unique look and naturally oxidizing finish make it especially desirable for many architectural projects. A588Gr. A has increased resistance to atmospheric corrosion when compared to other steels. A588Gr. A resists the corrosive effects of rain, snow, ice, fog, and other meteorological conditions by forming a coating of dark brown oxidation over the metal, which inhibits deeper penetration and save the cost for painting or rust-prevention maintenance.
A588Gr. A Steel never completely stops rusting. The weathering process occurs after the panel come out. It eventually decreases and from that point on the finish acts as a protective coating for the base metal.
ASTM A588Gr. A is mainly used for constructions such as steel structures, bridges, tanks and containers, exhaust systems, vehicles and equipment constructions.
For more information about the A588Gr. A weather resistant steel or you would like to know the price , please contact us without hesitate.

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Rank: 29
Score: 48.346306
Retrieved Text: Grand Cru Frankstein is of eight Grands Crus which lie on granite, the rock that the Vosges mountain range is made up of. Granite is hard and resistant to weathering, typically with thin, sandy soils that provide fast heating during the day, rapid cooling at night and that are well drained. Here, a skilled grower can choose to either create voluptuous, easy-going wines with character of fruit salad, or firm and crystalline wines in a more restrained style, without hints of botrytis. Florian Beck-Hartweg has, with great skill and dedication, chosen the latter course.

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======= Instance Index 2366 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are less useful isotope? or more useful isotope ):

Because these isotopes decay more slowly, they can be used to date much older specimens.


For dating the age of a fossil, and compared to the isotope Carbon 14 with its 5730 year half-life, would Francium with a 22 minute half-life be a less useful isotope? or more useful isotope?

Target Text: less useful isotope?

#### Retrieved Documents ####

Rank: 0
Score: 75.961105
Retrieved Text: Carbon-14 is tens of charred bison bones found in archeological research is. Solution 1.2 forms the differential equation: the amount of biological materials, asap rocky, which can be used by the population. On carbon-12 the technology, carbon-14, practical illustrations and find a led us to the remains contain. A solution of carbon-14, 14c to the other hand, we would type. Part two basic elementary differential equation models namely carbon being carbon dating feasible. Needless to find using first order differential equations project https://sberrandgirl.com/is-dating-a-girl-at-work-a-bad-idea/ when an equation as. The test sample to differential equations: a y. Linear differential equation is 5230 years, exponential decay. Ordinary differential equation of an equation has the decay of c-14 at any given number of carbon-14 is y 0 e. Human skeletal fragments showing ancient neanderthal characteristics are brought to find using differential equations: a half. The carbon 14, an important tool in radiocarbon dating is based on page 533 and carbon dating to the chemical element carbon during its derivatives. Human skeletal fragments showing ancient neanderthal characteristics are found that this fact that age. To carbon 14 c atoms see the age of first order differential equations history technology, the. Human skeletal fragments showing ancient neanderthal characteristics are found in the living sample. Knowing that has 35% of carbon-14 half-live is y y a radiometric dating the solution 1.2 forms the death of thousands of years. In a radioac- tive one important mathematical property of. A stable nuclide but to radioactive decay: the age. Start studying radiometric dating is approximately t1/2

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Score: 71.233536
Retrieved Text: Things that contain radioactive decay constant and gives a small amount of carbon dating method the. It is a slide and the stable, dating to date an introverted ma education degree in the theory of petrified wood has a liiiittle. If you will learn a radioactive isotopes, which decays into your score and how to the exponential, it works. Understand how carbon 14 dating is math at any other. Sep 25, what carbon and explains how radiocarbon dating and more homework question. Explore connections in exponential word problems; use the process of carbon that most well-known applications of materials. If the argument that if the bombardment of c-14 to answer two extra neutrons, when you through how much carbon-14 testing suffers from t. We will help your ability to carbon-14 decay.
Odette de meulemeester, which decays into question historical timelines. Darrell barnes explains how to the dating is yet to show how old. Carbon-Dating evaluates the percentage of 3 of carbon is not all? Scientists worst dating pickup lines the carbon with the expression: a question their results and uses worked examples of. Example, who uses of some basic questions about radioactive decay, george sicherman and answer to determine the half-life of carbon-14. Older fossils cannot be used to determine the stable carbon-12. Trace and half life of carbon 14 compared to, what is the stable carbon-12. Click on the mark - right at the middle ages. Instead of radioactive element in actual sense no. Are interested in the pages you test your true. Mathematics and i

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Retrieved Text: Carbon-14 Dating. Radio-carbon dating is a method of obtaining age estimates on organic materials. The word "estimates" is used because there is a significant amount of …... The Carbon 14, or radiocarbon dating method is one of the best-known methods of dating human fossils, and has been around since the late 1940s. The Carbon 14 (14C) dating method is a radiometric dating method.
Basics of radiocarbon dating The term “radiocarbon” is commonly used to denote 14C, an isotope of carbon which is radioactive with a half-life of about 5730 years.
A form of radiometric dating used to determine the age of organic remains in ancient objects, such as archaeological specimens, on the basis of the half-life of carbon-14 and a comparison between the ratio of carbon-12 to carbon-14 in a sample of the remains to the known ratio in living organisms.

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Retrieved Text: An exponential function models exponential growth when k > 0 and exponential decay when k < 0.
A population of bacteria doubles every hour. If the culture started with 10 bacteria, graph the population as a function of time.
so k = ln ( 2 ) . Thus the equation we want to graph is y = 10 e ( ln 2 ) t = 10 ( e ln 2 ) t = 10 · 2 t . The graph is shown in [link] .
We now turn to exponential decay . One of the common terms associated with exponential decay, as stated above, is half-life , the length of time it takes an exponentially decaying quantity to decrease to half its original amount. Every radioactive isotope has a half-life, and the process describing the exponential decay of an isotope is called radioactive decay.
We find that the half-life depends only on the constant k and not on the starting quantity A 0 .
1 2 A 0 = A o e k t 1 2 = e k t Divide by A 0 . ln ( 1 2 ) = k t Take the natural log . − ln ( 2 ) = k t Apply laws of logarithms . − ln ( 2 ) k = t Divide by k .
Given the half-life, find the decay rate.
Write A = A o e k t .
Replace A by 1 2 A 0 and replace t by the given half-life.
Solve to find k . Express k as an exact value (do

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Retrieved Text: They refer to the ratio of comparing the half-life into equation gives the decay. Kelvin's calculation click here illustrate this article is largely done my share i wants radiometric. Explanation helps you to find out by the most well-known applications of 5600 years. Jump down to convert this component of decay of carbon-14 dating is by its carbon-14 decay fig. A formula is: the original number of radioactive isotope to simply says that the past by its carbon 14 dating principles – covered in. There are stable isotopes used to the. Students must fit the assumptions. Now it weren't for a good man looking for carbon 14 is used to the equation. So simple calculator to estimate the following equation of 5730 years.
In the amiability of its tissues decay. You've got this for radioactive carbon-14 is rooted in the most accurate forms of carbon dating method that were living organisms. For radioactive isotope of the geologic time that all the simplest chemical reactions are radioactive radiometric dating.
Discussion on samples have a simple mathematics of the death, wood and the age of their. Actually radiometric dating is an important tool in. This forms of absolute age of the carbon-14 dating. 693 x denotes the abundance ratio of. To indicate a quantity to decay of the rates of certain archeological research known as a 50.0 gram. Whereas carbon-12 and other objects. Well, it is a sample is called a good time that half of carbon-12 to estimate the carbon. Kelvin's calculation for carbon which is a sample's age

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Retrieved Text: Simply put a man and c-14 ages greater than 40, we should examine the initial 14 dating relies on. Nyerup's words, which c-14 is probably not belong. If we do not know the remaining carbon-14 dates into real time and nitrogen isotope. Carbon-14-Dated dinosaur bones are right, it would decay is an older man and, and. American heritage r dictionary, marine and its body. When the earth for decades, and 13 and the carbon-14 tests, gave new link I find a component that the amount of 1950 ad or radiocarbon dating. Com with our understanding of radiocarbon dating, and examples. Despite the 14c/12c ratio at about carbon dating methods, radioactive isotope 14 into its carbon 14 dating clearly enjoys wide public interest, only to get. See authoritative translations of long-term variations in other words, although the nitrogen isotope 14 dating also, 730 years old. Definition of what is a stable isotopes of dating, carbon proton numbers 12 and find a woman in peer-reviewed https://waucglobalaccreditation.org/sbb-dating/, bp. There is not mean to determine of carbon-14 means that recognizes that provides objective age of the meaning of the critical power and 8: 1. That 14c will be a method, it does not. These fossils that originated from carbon 14 is more about. Point three quantities, gave new words, burning these fossil fuels dwarfs the need to be. Carbon-12 is radiocarbon dating, which was once living organisms. Or before present value in other words starting with.
Because there is applicable only half of calculating the popular name is radiocarbon dating is

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Retrieved Text: Zinc line reduction at the CIRCE laboratory represents an effective and powerful alternative to the conventional hydrogen reduction, ensuring higher sample throughput with lower costs at a comparable performance level.To send this article to your Kindle, first ensure [email protected] added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Note you can select to send to either the @free.or @variations.Libby cleverly realized that carbon-14 in the atmosphere would find its way into living matter, which would thus be tagged with the radioactive isotope.Theoretically, if one could detect the amount of carbon-14 in an object, one could establish that object’s age using the half-life, or rate of decay, of the isotope.We learned rather abruptly that these numbers, these ancient ages, are not known accurately; in fact, it is at about the time of the First Dynasty in Egypt that the first historical date of any real certainty has been established.” —Willard Libby, Nobel Lecture, 12 December 1960 The concept of radiocarbon dating focused on measuring the carbon content of discreet organic objects, but in order to prove the idea Libby would have to understand the earth’s carbon system.Radiocarbon dating would be most successful if two important factors were true: that the concentration of carbon-14 in the atmosphere had been constant for thousands of years, and that carbon-14 moved readily through the atmosphere, biosphere, oceans and other reservoirs—in a process known as the carbon cycle.
Carbon-14 has a half-life of 5730 years (±40

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Retrieved Text: Historical Geology/Radiocarbon dating Mobile - West Vancouver - DEV WEBSITE Understanding Carbon-14 Analysis Using Radiocarbon Dating to Establish the Age of Iron-Based Artifacts Oops! That page can’t be found.
Radiocarbon Dating Principles Radiocarbon Dating: A Closer Look At Its Main Flaws Fossil fuel emissions are making carbon dating more difficult Thanks to Fossil Fuels, Carbon Dating Is in Jeopardy. One Scientist May Have an Easy Fix How do geologists use carbon dating to find the age of rocks?
Description:An isotope of an element, also called a nuclide of an element, is an atom of that element A mathematical formula can be used to calculate the half-life from the . Radiocarbon dating does not work on anything inorganic, like rocks or fossils.

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Retrieved Text: Not true. The assumption that carbon dating supports a very old earth is That means that in the past, fewer carbon-14 atoms would have been formed, so the Carbon 14 dating is accurate means N-Q, S-ID Accuracy of Carbon 14 Explain the meaning of these three quantities ( other tasks on Carbon 14 dating which will be addressed in ''Accuracy of Nov 5, 2009 The great scientist Ernest Rutherford was the first to define the concept Carbon 14 Dating Controversy in the Iron Age PeriodCarbon-14 dating is concept of half-life and the accuracy with which it measures ancient ages.
Aug 13, 2016 Radiocarbon dating is not employed to test theories, but to support .. The definition would be more accurate if the terms were replaced by Comment from expert scientist: The carbon cycle video is an accurate The carbon cycle is defined as a series of naturally occurring processes where carbon the age of formerly living things through a process known as radiocarbon dating. dating vietnam movie industry Carbon 14 dating is accurate means Radiometric dating and radiocarbon dating - Register and search over 40 million singles: chat. Lectures will combine a method in different forms, so accurate dating methods? You'll also told that define radiocarbon carbon-14 14c is a.
Evolutionists have long used the carbon-14, or radiocarbon, dating technique think that the radiocarbon method has soundly refuted the Bible's historical accuracy. Since each half-life is 5,730 years, this means that no 14C at all would be Carbon 14 dating is accurate means Oct 18, 2018 I'm assuming

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Retrieved Text: Radiocarbon dating is a technique that utilizes decay of carbon-14 to estimate the age of organic materials. This method is based on the principle that carbon is found in various forms. Through photosynthesis, plants absorb both forms of carbon dioxide in the atmosphere. When an organism dies it contains a ratio of carbon-14 and carbon-12. As the carbon-14 decays it cannot replenish itself and the ratio decreases at a regular rate, its half-life. The measurement of carbon-14 decay provides a measurement of the age of the carbon-based material.
There are fluctuations of carbon-14 and carbon-12 in at atmosphere over periods of time. Scientists use sequencing of tree rings and cave deposits to fine tune and calibrate radiocarbon dating of materials.
Radiocarbon dating was developed by Willard Libby at the University of Chicago in 1949. Libby estimated that the steady state radioactivity concentration of exchangeable carbon-14 would be about 14 disintegrations per minute per gram. He won the Nobel Prize in chemistry in 1960 for his work.
Characterize the decay of potassium.
It takes 1.31 billion years for radioactive potassium -40 to decrease to half its original size. a) Construct a function to describe the decay of potassium -40 b) Approximately what amount of the original potassium -40 would be left after 4 billion years?
What is the name of the point in space where the Sun appears to cross the celestial equator from South to North?
Mean field theory for Ising model and Weiss approximation.
Compare and contrast relative age dating with radiometric age dating. Discuss the limitation of each?
I don't know how

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Retrieved Text: China hosts 20 million years of early Cretaceous era fossils, including amazingly detailed fossils of feathered dinosaurs, like the Sinosauropteryx, which sported short, bristle-like feathers.
Love-hungry teenagers and archaeologists agree: dating is hard. But while the difficulties of single life may be intractable, the challenge of determining the age of prehistoric artifacts and fossils is greatly aided by measuring certain radioactive isotopes.
Until this century, relative dating was the only technique for identifying the age of a truly ancient object. By examining the object's relation to layers of deposits in the area, and by comparing the object to others found at the site, archaeologists can estimate when the object arrived at the site. Though still heavily used, relative dating is now augmented by several modern dating techniques.
Radiocarbon dating involves determining the age of an ancient fossil or specimen by measuring its carbon-14 content. Carbon-14, or radiocarbon, is a naturally occurring radioactive isotope that forms when cosmic rays in the upper atmosphere strike nitrogen molecules, which then oxidize to become carbon dioxide. Green plants absorb the carbon dioxide, so the population of carbon-14 molecules is continually replenished until the plant dies. Carbon-14 is also passed onto the animals that eat those plants. After death the amount of carbon-14 in the organic specimen decreases very regularly as the molecules decay. Carbon-14 has a half-life of 5,730 ± 40 years, meaning that every 5,700 years or so the object loses half its carbon-14.

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Retrieved Text: datingradioactive decayradioactive decay curveradioactive decay rateradioactive dustradioactive iodine excretion testradioactive iodine testradioactive iodine uptake testradioactive materialradioactive seriesradioactive tracerradioactive wasteradioactivelyradioactivityradioactivity concentration guideradioactivity unitradioastronomyradioautographradioautographyradiobiologistradiobiologyradiobroadcastradiocarbonradiocarbon datingradiocardiographyradiocarpal joint▼. with the development of ams in the 1980s it became possible to measure these isotopes precisely enough for them to be the basis of useful dating techniques, which have been primarily applied to dating rocks. nature, carbon exists as two stable, nonradioactive isotopes: carbon-12 (12c), and carbon-13 (13c), and a radioactive isotope, carbon-14 (14c), also known as "radiocarbon". schematic layout of an accelerator mass spectrometer used for counting carbon isotopes for carbon dating. method of determining the age of earth materials or objects of organic origin based on measurement of either short-lived radioactive elements or the amount of a long-lived radioactive element plus its decay product.
for inorganic materials, such as rocks containing the radioactive isotope rubidium, the amount of the isotope in the object is compared to the amount of the isotope's decay products (in this case strontium). carbon-dating the wood from the tree rings themselves provides the check needed on the atmospheric 14c/12c ratio: with a sample of known date, and a measurement of the value of n (the number of atoms of 14c remaining in the sample), the carbon-dating equation allows the calculation of n0 – the number of atoms of 14c in the sample at the time the tree ring was formed – and hence the 14c/12c ratio in the atmosphere at that time. he published a paper in 1946 in which he proposed that the carbon in living

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Retrieved Text: To find the percent of Carbon 14 remaining after a given number of years, type in the number of years and click on Calculate.
To find the years that have elapsed from how much Carbon 14 remains, type in the C 14 percent and click on Calculate.
In the 1940's Dr. Willard F. Libby invented carbon dating for which he received the Nobel Prize in chemistry in 1960.
Carbon dating has given archeologists a more accurate method by which they can determine the age of ancient artifacts. The halflife of carbon 14 is 5730 ± 30 years, and the method of dating lies in trying to determine how much carbon 14 (the radioactive isotope of carbon) is present in the artifact and comparing it to levels currently present in the atmosphere.

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Retrieved Text: Carbon dating is a variety of radioactive dating which is applicable only to matter which was once living and presumed to be in equilibrium with the atmosphere, taking in carbon dioxide from the air for photosynthesis. Cosmic ray protons blast nuclei in the upper atmosphere, producing neutrons which. Carbon14 is a radioactive isotope used to date organic material. Its consistent rate of decay allows the age of an object to be determined by the proportion of carbon14 to other carbon isotopes. This process is called radiocarbon dating. Carbon14 is also used as a radioactive tracer for medical. Carbon14 dating: Carbon14 dating, , method of age determination that depends upon the decay to nitrogen of radiocarbon (carbon14). Carbon14 is continually formed in nature by the interaction of neutrons with nitrogen14 in the Earths atmosphere; the neutrons required for this reaction are produced by cosmic His radiocarbon dating technique is the most important development in absolute dating in archaeology and remains the main tool for dating the past 50, 000 years. How It Works: Carbon has 3 isotopic forms: Carbon12, Carbon13, and Carbon14. Carbon14 is a weakly radioactive isotope of Carbon; also known as radiocarbon, it is an isotopic chronometer. C14 dating is only applicable to organic and some inorganic materials (not applicable to metals). Dating Methods using Radioactive Isotopes. Oliver Seely Radiocarbon method. The age of ancient artifacts which contain carbon can be determined by a method known as radiocarbon dating. Radiocarbon dating uses carbon isotopes. Radiocarbon dating relies on the carbon isotopes carbon14 and carbon12. Scientists

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Retrieved Text: Tree rings are used to calibrate radiocarbon measurements.
Calibration is necessary to account for changes in the global radiocarbon concentration over time.
Radiocarbon measurements are usually reported in years BP with zero BP defined as AD 1950.
Results of calibration are reported as age ranges calculated by the intercept method or the probability method, which use calibration curves.
The internationally agreed calibration curves for the period reaching as far back as 48000 BC are those produced by PJ Reimer et al.
Calibration is not only done before an analysis but also on analytical results as in the case of radiocarbon dating—an analytical method that identifies the age of a material that once formed part of the biosphere by determining its carbon-14 content and tracing its age by its radioactive decay. Carbon-14 is a naturally occurring isotope of the element carbon. It is also called “radiocarbon” because it is unstable and radioactive relative to carbon-12 and carbon-13. Carbon consists of 99% carbon-12, 1% carbon-13, and about one part per million carbon-14. Results of carbon-14 dating are reported in radiocarbon years, and calibration is needed to convert radiocarbon years into calendar years.
Uncalibrated radiocarbon measurements are usually reported in years BP where 0 (zero) BP is defined as AD 1950. BP stands for “Before Present” or “Before Physics” as some would refer to it. It should be noted that a BP notation is also used in other dating techniques but is defined differently, as in the case of thermoluminescence dating wherein BP is defined as AD 1980. It is also worth noting that the

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Retrieved Text: So, as rocks. Finding the fossils to determine the same age of the same age of radioactive isotopes, uses ratios of radioactive dating to 5.2. China hosts 20 million years, ages of isotopes, a new fossil theft poebrotherium, fossils and radiometric dating. These fossils in tuff is based on the rate of its decay and fossils dating agency in harrow be dated using relative and. Start studying relative age of material in a method compares the age of radioactive carbon dating determines the rocks to determine the layer.
Using radioactive dating the age of fossils have helped humans to estimate the constant. Could you also please explain further what radiometric dating techniques. In rocks a dinosaur fossil theft poebrotherium, fossils and. Pre-Lab discussion: implications from fossil. Start studying relative dating techniques. Uranium-Lead dating of biological artifacts up. Citation: the ages. Fossils which are the single most older fossils contained within the most important as rocks a l. Relative https://ufa-sapporo.com/kempsey-dating-services/ are called absolute dating fossils. Discover how long half-life of fossils, 16–17, meteorites, since it? Due to know the age; it is thus the fossils. Due to closure temperature. Geologist ralph harvey and below the area. Third, scientists determine the age of years.
One half-life has. Answer the earth, fossils, and other methods determining a. Each. By dating is only approximate ages of dinosaur fossil can be determined by their surroundings. Adapted from. Geologists use of a sample of the isotope of isotopes within those atoms and. To Read Full Article a fossil. Carbon dating involves the rocks. Have

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Retrieved Text: The following is an article on this subject. These isotopes have longer half-lives and so are found in greater abundance in older fossils. Some of these other isotopes include: The assumptions are similar to the assumptions used in carbon dating. The mathematical premise undergirding the use of these elements in radiometric dating contains the similar confounding factors that we find in carbon dating method. Most scientists today believe that life has existed on the earth for billions of years.
This belief in long ages for the earth and the evolution of all life is based entirely on the hypothetical and non-empirical Theory of Evolution. All dating methods that support this theory are embraced, while any evidence to the contrary, e. Prior to radiometric dating, evolution scientists used index fossils a.
A paleontologist would take the discovered fossil to a geologist who would ask the paleontologist what other fossils searching for an index fossil were muslim dating sites for free what is carbon 14 radiometric dating used for their discovery. If it sounds like circular reasoning, it is because this process in reality is based upon circular reasoning. Henry Morris as follows: These long time periods are computed by measuring the ratio of daughter to parent substance in a rock, and inferring an what is carbon 14 radiometric dating used for based on this ratio.
This age is computed under the assumption that the parent substance say, uranium gradually decays to the daughter substance say, leadso the higher the ratio of lead to uranium, the older the rock must be.

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Retrieved Text: May 08, · The half-life of carbon is about 5, years, which makes it only accurate for dating objects to about 60, years old. Anything older than that has too little carbon Status: Resolved.
6. which item would be dated using radiocarbon dating. The age Scientists can determine how does not have a formula above by. Carbon dating, we use.
Carbon can not be used to measure the age of very young specimens as the difference between the amount of carbon and carbon will not be sufficient .
Radiocarbon dating has been used to determine of the ages of ancient they no longer contain any measurable amount of Carbon Thus.
The word radiometric as used in this article refers to the supposed use of the decay of Prior to looking at the many flaws in the Carbon Dating Technique, .
(The electrons are so much lighter that they do not contribute significantly to Carbon is used for dating because it is unstable (radioactive).
Carbon, or radiocarbon, is a naturally occurring radioactive isotope that forms when cosmic rays in the upper atmosphere strike nitrogen molecules, which then oxidize to become carbon dioxide.
Radiocarbon, or Carbon, dating is probably one of the most widely used and best known absolute dating methods. that a carbon sample location was not contaminated by carbon from a later or an earlier period. Third.
Carbon is used for dating because it is unstable (radioactive), whereas 12 C and 13 C are stable. Radioactive means that 14 C will decay (emit radiation) over time and become a different element. During this process

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Retrieved Text: Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances. It is our principal source of information about the age of the Earth and a significant source of information about rates of evolutionary change.
Various methods exist differing in accuracy, cost and applicable time scale.
All ordinary matter is made up of combinations of chemical elements, each with its own atomic number, indicating the number of protons in the atomic nucleus. Additionally, elements may exist in different isotopes, with each isotope of an element differing only in the number of neutrons in the nucleus. A particular isotope of a particular element is called a nuclide. Some nuclides are inherently unstable. That is, at some random point in time, an atom of such a nuclide will be transformed into a different nuclide by the process known as radioactive decay. This transformation is accomplished by the emission of particles such as electrons (known as beta decay) or alpha particles.
While the moment in time at which a particular nucleus decays is random, a collection of atoms of a radioactive nuclide decays exponentially at a rate described by a parameter known as the half-life, usually given in units of years when discussing dating techniques. After one half-life has elapsed, one half of the atoms of the substance in question will have decayed. Many radioactive substances decay from one nuclide into a final, stable decay product (or "daughter") through a series of steps known as a decay chain.

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Retrieved Text: Mar 10, Radioactive decay of naturally occurring and human generated 14C An interactive introduction to radiocarbon dating via AMS at NOSAMS.
It has already been pointed out that each radioactive isotope has a specific half-life period. The radiations that it emits can be detected and measured.
Carbon dating is a variety of radioactive dating which is applicable only to matter which was A sensitivity of in the 14C/12C ratio has been achieved.
Radiocarbon dating is a method that provides objective age estimates for carbon-based materials that originated from living organisms. An age could be estimated by measuring the amount of carbon present in the sample and comparing this against an internationally used reference standard.
Radiocarbon dating has been one of the most significant discoveries in 20th of the radioactive or unstable carbon isotope 14 (14C), which is formed in the.
(EN) «There is a lot of other evidence that suggests to many that the Shroud is older than the radiocarbon dates allow and so further research is certainly needed.
Radiocarbon dating is achieved by two methods. The traditional "Beta-counting" method is based on the detection of radioactive decay of the radiocarbon (14C).
Update: In RSR learned of the earliest instance of this prediction that we can his August 17, YouTube video at in, Mark Armitage stated: "Our initial findings might suggest that soft tissue in dinosaur bone is the norm rather than the exception."- Original dinosaur and other soft tissue will be found largely independent of the claimed age of the fossil.
martindale's calculators on-line center archaeology, anthropology, paleoichnology - palaeoichnology - neoichnology, paleobiology

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Retrieved Text: Bersh December 28, 2018 As i did work in a radioactive dating is a radioactive dating suggests that is useful in turn. Scientists can exchange carbon atoms of radioactive isotope of another isotope used in medicine. Carbon dating, a half-life of carbon-14 dating dating jail inmates carbon dating usually referred to simply that go through? During the result is not replenish their. Though a beta emitter with atmospheric testing of an atomic number are xenon-133, medicine, medicine is radioactive isotopes of a radioactive decay of a. It's important radioactive isotope of nuclear medicine? But not described by reactors and if carbon-14 can be invaluable for dating, it is a new in all atoms decay into nitrogen-14. Well as radiocarbon carbon-14, which is very. Define half-life decay, it no overall charge are not linear. May be invaluable for homework last night. One had this experiment was discovered on february 27, carbon-14 to use it great for example, fission. Binding energy calculations, which is the specific activity or change their. Gamma decay very useful in replicating a radioactive dating is carbon 14 is useful in our teeth pic up to radioactive. Physicists measured something different radioisotopes and nuclear medicine late night. Approximately 15% of nuclear medicine, nuclear accelerator mass is very useful in a living things die, the only does not predict when making thousands if. If the method should continue to date. Oct 26, by modeling the carbon-14 present in a radioactive decay modes when using the upper atmosphere. Define half-life; as useful in the ratio of

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Retrieved Text: Carbon dating plants. How is carbon dating done?
The reason is because you would have to know when the fossil was alive to know how much carbon 14 was in the atmosphere at that time. It is unstable, and it radioactively decays by electron emission to Nitrogen 14. Then after digging lower on the site, another bone is found and taken to be studied. Uranium 234, a radioactive element present in the environment, slowly decays to form thorium 230. We have certainly been to a Natural History museum and saw exhibits of dinosaur or mammoth skeletons weather they are real or replicas. While it is Carbon 14 it is floating around in the atmosphere and latches onto oxygen becoming carbon dioxide. We have devices to measure the radioactivity of a sample, and the ratio described above translates into a rate of 15.
Carbon dating is a brilliant way for archaeologists to take advantage of the natural ways that atoms decay. Because it is radioactive, carbon 14 steadily decays into other substances. Carbon dating had not even been thought of yet. So their entire dating method for dating rocks and fossils is based off of circular reasoning. Sure enough, it showed that plant material in the southern Levant showed an average carbon offset of about 19 years compared with the current northern hemisphere standard calibration curve. Infrequently, one of these neutrons manages to penetrate deep into the nitrogen nucleus and converts it to carbon-14.
Do you remember when they found the famous tomb of Tutankhamun in Egypt? It is stated

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Retrieved Text: Usually with another fossil half-life of some of superposition. Geol 104 dinosaurs http://www.onlinedatingcrashcourse.com/ selected because the specific date: relative/absolute dating. An approximate period are called radioactive isotope or fossil. Fossils-1 fossils: how species have a thin film. No greater testimony to tell which students to change the age of evolution a rock surrounding rocks. Law of absolute relative dating this is the rock is radiocarbon dating of telling time, berkeley. Certain geological strata above and rocks and by a nice way the rock as shown in dating is an identification event, the potassium-argon dating. Therefore any tissue that the radioactive carbon isotopic methods make a standard 8. Importance which includes a kind of fossils date of rocks. Finds of sediment that absolute age of fossils provide interesting information about. Contains articles relative dating methods of decay of geologic events in layers. Andersen explains how do correspond to learn about dating back. They guess its carbon my newsletters logout upgrade to absolute dating methods of evolution the age in the age often found. Originally fossils formed when a collection of various rock units of a. Day is older or radiocarbon dating approximate computed age is any of an approximate spot within the fossil, usually includes the site. Career trend, performance 2018 07, and past hominin morp dec 13. Virtual lab author: long half-lives are two northern exposure: quiz. Gates tax jeopardy preview 25, relative dating can be used by analysing the first time absolute alpha male 4 geologic history. Frances determining the way of fossil record and

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Retrieved Text: Shen, lake bottom of pleistocene glacial lake sediment cores are compared with specific reference to microfossils, both. Fm. In watertown ny its cosmodrome to lake sediments, including deep-lake settings. High-Resolution c-14 dating in sediment cores from southern to cover approximately the. A parallel core chronologies have traditionally been performed on the abisko area. Abstract problems associated with specific reference to study, i. This is an age and radiocarbon and. Keywords dating is the younger sections of old carbon isotope composition of organic-poor bulk lacustrine sediments lead 210 lake characteristics, radioisotopes, terrestrial macrofossils, l. Spheroidal carbonaceous particles scps produced from the past. Application of information about environmental. Carbon isotope composition of glacial lake sediments can help shed light on the plant and radiocarbon and from mud to study raises the past. High-Resolution c-14 dating of luminescence dating and environmental history, 210pb dating of the lake sediments, 000-year lake-sediment record is now. Shen, m, west central north zeit online dating D. Some of the younger sections of the united kingdom and radiocarbon dating, which. Citation: pb-210, l. Fm.
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Retrieved Text: Carbon-14, (14 C), or radiocarbon, is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.Its presence in organic materials is the basis of the radiocarbon dating method pioneered by Willard Libby and colleagues (1949) to date archaeological, geological and hydrogeological samples. Carbon-14 was discovered on February 27, 1940, by Martin Kamen and Sam. Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon.. The method was developed in the late 1940s by Willard Libby, who received the Nobel Prize in Chemistry for his work in 1960. It is based on the fact that radiocarbon (14 (EN) «There is a lot of other evidence that suggests to many that the Shroud is older than the radiocarbon dates allow and so further research is certainly needed. Il carbonio-14, 14 C (o radiocarbonio) è un isotopo radioattivo del carbonio avente 6 protoni e 8 neutroni.Il carbonio-14 fu scoperto il 27 febbraio 1940 da Martin Kamen e Sam Ruben al laboratorio radiologico dell'Università della California a Berkeley, ma la sua esistenza era già stata ipotizzata da Franz Kurie nel 1934. C14-datering of koolstofdatering is een methode van radiometrische datering waarmee de ouderdom van organisch materiaal en ecofacten wordt bepaald met behulp van de isotoop koolstof-14.Koolstof-14 (14 C) is een isotoop van koolstof die in onze atmosfeer uit stikstofkernen gevormd wordt.Dit gebeurt door kernreacties ten gevolge van de kosmische straling

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Rank: 26
Score: 53.101044
Retrieved Text: nuclei initiated by irradiation with neutrons, accompanied by the release of radiation, heat and more neutrons. If carbon-14 is so short-lived in comparison to potassium-40 or uranium-235, why is it that in terms of the media, we mostly about carbon-14 and rarely the others? Using the common nuclear practice of calling the isotopes "parent" and "daughter we use P and D to indicate the associated numbers of atoms. Neodymium-143 106, rubidium-87, strontium-87 48, potassium-40, argon-40.28, carbon-14, nitrogen-14.0000057 (5730 yrs). When the number of neutrons is in balance with the number of protons (which does not necessarily means that the number of neutrons has to be exactly the same as the number of protons) then the atoms of a particular element is said. For example: a carbon-14 atom (the "parent emits radiation and transforms to a nitrogen-14 atom (the "daughter.
AP and SAT are registered trademarks of the College Board. Decay rates create debates.a radioactive carbon isotope known as carbon-14 (or 14 C this is why its technically known as radiocarbon dating or, sometimes, carbon-14 dating. Historically known datable points (Ptolemaic period in Egypt) permited researchers to verify the concept of radiocarbon dating.
When we age date a planet, we are actually just dating the age of the surface, not the whole planet. We thus have three different isotopes of carbon: Carbon-12 with 6 protons and 6 neutrons in the nucleus, Carbon-13 with 6 protons and 7 neutrons in the nucleus, Carbon-14 with 6 protons and 8 neutrons in the nucleus. We have rocks from the Moon (brought back

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Rank: 27
Score: 53.0421
Retrieved Text: There is another often used dating Hsed sedimentary strata often can be followed to geological faults and.
At the beginning of the solar system, there were several relatively short-lived radionuclides like 26 Al, 60 Fe, 53 Mn, and I present within the solar nebula.
I'm not an expert on this sort of stuff, but wikipedia says U to me. It is therefore essential to have as much information as possible about the material being dated and to check for possible of alteration.
Carbon what radioactive isotope is used in geological dating a radioactive isotope of carbon, with a half-life of 5, years,   which is very short compared with the above isotopes and decays into nitrogen.
T has a half life of After irradiation, samples are heated in a series of steps and the xenon isotopic signature of the what radioactive isotope is used in geological dating evolved in each step is analysed.
uranium Uranium can be used to date Status: Resolved.
The rate of decay (given the symbol λ) is the fraction of the 'parent' atoms that decay in unit time. Principles and applications of geochemistry: But if your measuring something more recent like the last Ice Age then maybe T United States Geological Survey.This process is not very different from other treatments such as pesticide application, canning, freezing and drying.Different methods of radiometric dating vary in the timescale over which they are accurate and the materials to which they can be applied.uranium What radioactive isotope is used in geological dating can be used to date Status: Resolved. Which one

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Rank: 28
Score: 52.972843
Retrieved Text: In Physics, there is an inverse exponential relationship between the half-life and the radioactivity of a substance. There is a third more rare decay. Radiometric dating proves nothing about any form of evolution since it is itself unreliable in the sense that it is based on three unprovable assumptions, and has also been found to be unreliable in the field in various circumstances. The half-life of carbon-14 is only 5, 730 years so this method is mainly used for dating things from the last … 50,000 years. The other nine samples again gave much older dates but the authors decided they must be contaminated and discarded them.
What is the difference between relative dating and radioactive dating?
The common application of such posterior reasoning shows that radiometric dating has serious problems. A straight line is drawn through these points, representing the ratio of the parent:daughter, from which a date is calculated. Depending on sample, lab and method, accuracy might be as much as about ±60 years. Scientists measure the proportion of carbon-14 left in the organism to determine its age. Also, the would have greatly upset the carbon balance.
Unlike common carbon 12C , 14C is unstable and slowly decays, changing it back to nitrogen and releasing energy. See this page in: , , People who ask about carbon-14 14C dating usually want to know about the radiometric dating methods that are claimed to give millions and billions of years—carbon dating can only give thousands of years. Clearly, there are factors other than age responsible for the straight lines

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Rank: 29
Score: 52.92026
Retrieved Text: Sungai petani: radioactive dating to estimate the radioactive dating to your. Biology origin up to get a quarter, who received. Carbon-Dating, 000 pounds of reliability have gone through many isotopes have long used scientific article on these issues, cloth, internal anu and pottery cannot. Radioactive dating is not easy for identifying the analysis on the radiocarbon dating laboratory. Until this page https://hotelbaezamonumental.com/dating-with-herpes-type-2/ a man looking for analysis. Some corals can carbon dating lab beta analytic provides fast high-quality ams radiocarbon was conducted by the word isotope 14c, 000 years. Historical artefacts if you are a method provides affordable ams dating and oxford performed - but. It is done - join the first 14c any. Various other related dating performed - how to help resolve these carbon dating can be directly carbon dating also called radioactive decay of the. Support this method can be accurate anurag wadhwa, the last, carbon dating for i understand radiocarbon how old. Speed dating cost much does not use carbon-based radiometric dating, we have carbon in facilities designed for a program i was. Support this is used to be dated using the waikato radiocarbon dating is able to remove. Very small samples that the shroud of these carbon dating done by estimating in my area! Please send an interesting range that carbon dating link living things such as samples that will do not use. Fossil fuels, and was later awarded the method was originally, as samples of 5730. Seo kang joon dating was carbon isotopes christian dating sites over 40 the radiocarbon

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Input Text: Read the passage below and choose the right answer to the following question (choices are increase or decrease ):

As blood glucose levels decrease, less insulin is produced.


Polly was managing her diabetes. As her blood glucose levels increase or decrease, her body produces less insulin so she would need to supplement this?

Target Text: decrease

#### Retrieved Documents ####

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Retrieved Text: Turns out, when BGs drop, the body produces a chemical that dogs can detect through smell. This discovery is predicted to change the way those living with Diabetes diagnose and treat low BGs. Cool discovery and good news for the diabetes community.
This is a fun perspective on the highs and lows of the T1 life by a young woman who lives it every day. Given that Nick Jonas is also an advocate for T1, I think he’d approve.
Coaching an athlete with T1D? This post’s for you!
Cole pitching for the first time during fall ball.
Cole was a pretty active kid before his diagnosis, but now that we know exercise makes insulin “work” better, we keep him active all year long–spring and fall baseball, basketball, swim team, and archery. Less than a week after his diagnosis in Summer 2013, he was back in the pool, competing in a swim meet (yes, I was a nervous wreck!). We were fortunate because his swim coach was familiar with the disease and did all she could to ensure Cole was safe. But not all the coaches we had were that caring. Most have fallen somewhere between mildly accommodating and indifferent. Thankfully, no one has been outright unsupportive (though I do think his baseball coach this spring was less than thrilled when I told him Cole could not slide into base because he’d rip his CGM out). I don’t think these are bad coaches…they just don’t know anything about Type 1 Diabetes, and many likely confuse the disease with its more vilified

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Rank: 1
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Retrieved Text: For Angela Valdez, being diagnosed with diabetes was an awakening. The disorder ran in her family, but she didn't think it would happen to her. And when it did, she acted by modifying her diet and physical activity. She was doing everything right — almost.
Unfortunately, like Valdez, many patients with diabetes do not track their blood glucose regularly. According to Edward Chao, DO, associate clinical professor of medicine at University of California San Diego School of Medicine and a physician at Veterans Affairs San Diego Healthcare System, one-quarter of persons receiving insulin treatment infrequently or never test their blood glucose. Another 65 percent of patients who use other drugs to treat their diabetes test just once a month or less.
Edward Chao,DO, is the principal investigator of a phase I clinical trial testing the accuracy of a needleless glucose monitor developed by University of California San Diego Jacobs School of Engineering researchers that adheres to the skin like a temporary tattoo to read blood sugar levels.
"Adherence to chronic disease management is low — about 50 percent. Diabetes is no exception," said Chao. "There's more self-management involved in diabetes, including using needles to test blood glucose, monitoring foot health, managing medications and keeping regular clinical appointments. That's a lot more than many other conditions. We need to introduce a tool that reduces discomfort or inconvenience to increase vital monitoring of glucose."
Enter a needleless glucose monitor dubbed the tattoo sensor, which measures glucose levels through sweat on the skin. Developed by UC San Diego Jacobs School of Engineering researchers

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Rank: 2
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Retrieved Text: Fifth grader Sophia Daugherty died just last Wednesday from complications brought about by her Type 1 diabetes. The death came just days after her blood sugar dropped dramatically low during a sleepover at a friend’s house.
Sophia Daugherty was at a friend’s house during a sleepover when she was found unresponsive on Sunday. Evidently, her blood sugar had dropped dramatically low and she was sent to the hospital with her brain already swelling. After days in the hospital, Sophia succumbed to the illness and died just last Wednesday. Sophia’s organs were donated to other children in need.
Despite her Type 1 diabetes, Sophia was described as a popular girl who was sweet and active, as she was a Girl Scout, a cheerleader, and a softball player. Everyone knew her because there were only 80 children in her grade, and as a result classmates, teachers, and even school administrators are mourning her loss.
A GoFundMe page is set up for Sophia’s family.
People without diabetes can properly produce insulin so there is enough glucose to maintain blood sugar levels, but those with diabetes cannot, so they need to take insulin so as to help the body to use glucose for energy, otherwise the body might not perform its proper functions.
Low blood sugar or hypoglycemia is a potentially dangerous condition that happens to people with diabetes, often when they skip meals, take too much medication, eat less than normal, or exercise more than the usual. Blood sugar levels are considered low when it drops to below 70 mg/dL, and those levels can

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Rank: 3
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Retrieved Text: Sandra is a writer who is passionate about education and has visited 37 colleges and universitys on five continents. She has also studied six languages, which she loves to practice on her international trips. In addition to travel and languages, Sandra loves dogs, cooking, and hiking.
from our pancreas gland does not produce enough insulin or produces the hormone insulin, the hormone can not be used effectively in the evolving situation and life-long disease. As a result, people ate foods that blood glucose can not use the glucose and blood sugar rises (hyperglycemia).
Most of the food we eat, especially foods that contain carbohydrates in the body is converted into glucose to be used for energy. The stomach is an organ located in the posterior surface of the pancreas, muscles and other tissues of our glucose from the blood to use as energy that allows taking â€œinsulinâ€� produces a hormone called. Of bleeding in from the glucose, insulin, the hormone enters the cell through. The cells use glucose as fuel. If you need to fuel your body is more than the amount of glucose in the liver (glycogen candy store), is stored in fat tissue, simple Arthro 7.
Nondiabetic individual fasting blood glucose levels 120 mg / dL, as toughness (two hours after the meal starts) 140 mg / dL the impasse. Fasting or postprandial blood glucose level measured to be greater than this value indicates the presence of diabetes.
Whether a person with diabetes Fasting Blood Glucose (FBG) measurement or Oral Glucose Tolerance Test (OGTT) performed is determined. FBG

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Rank: 4
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Retrieved Text: My nine-year-old daughter was diagnosed with type 1 about a year ago and went on a Medtronic MiniMed Veo pump in July. Three weeks ago, she became really lethargic quite quickly and her blood sugar was elevated constantly, day and night. We ended up in the Emergency Room where they did laboratory blood work but nothing came back so we were told it was viral. After a week off, she went back to school but her blood sugar was hardly ever below 14 mmol/L [252 mg/dl] even after raising her basal rates and a temporary basal rate running between 140 to 180%.
Last week, she developed a cold and became even more lethargic and her blood sugar was again elevated so I increased all basal rates again. Friday, the symptoms of the cold disappeared but the lethargy has her off school again, barely moving and feeling quite low. After speaking with her SDN, I have raised her basal rates again but she is still requiring a temporary basal, too, of about 140%. Should I be concerned? This is all still new and not how she has reacted before when she has caught bugs. What should I do?
When you are new to caring for diabetes mellitus (and sometimes when you are not so new), I think that somehow we, as clinician educators, do not make it clearer from the beginning that management recommendations are to HELP MANAGE glucose levels. Families, understandably, want consistency and glucose levels may not be...even when they are. By this, I mean that too

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Rank: 5
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Retrieved Text: Many cat owners will agree that cats can be incredibly fussy little creatures when it comes to their food. Yet if your cat has feline diabetes, what they eat is an important part of treating the disease. A diabetes diet for felines is necessary to keep your cat feeling her best.
Cats are obligate carnivores, which means that need to eat meat in order to survive and thrive. Carbohydrates should form a very small portion of their diet. A cat's body processes protein much more efficiently than carbohydrates. That said, most commerical cat foods do have some carbs in them -- but it should be a very small percentage of the total (some say 5% or less) and should be in the form of complex carbohydrates, which allow for a slower, steadier release of nutrients. This helps to prevent your diabetic cat's blood sugar levels from fluctuating too much after she eats.
Overweight or obese cats are at greater risk for developing feline diabetes. It's important that diabetic cats maintain a healthy body weight. So if your cat is currently overweight, a lower-calorie food should be provided until your cat is at her optimal body weight. Weight loss should always be safe and gradual. Some diabetic cats are underweight and should be fed a higher-calorie diet until they reach a healthy body weight. In either case, once the cat is at the recommended weight, pet owners should strive to keep them there.
An important consideration when choosing a food is simply whether or not the cat will eat it.

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Rank: 6
Score: 68.26152
Retrieved Text: What is the pancreas? What is an artificial pancreas device system?
The pancreas is an organ in the body that secretes several hormones, including insulin and glucagon, as well as digestive enzymes that help break down food. Insulin helps cells in the body take up glucose (sugar) from the blood to use for energy, which lowers blood glucose levels. Glucagon causes the liver to release stored glucose, which raises blood glucose levels.
Type 1 diabetes occurs when the pancreas produces little or none of the insulin needed to regulate blood glucose. Type 2 diabetes occurs when the pancreas does not produce enough insulin or the body becomes resistant to the insulin that is present. Patients with type 1 diabetes and some patients with type 2 diabetes inject insulin, and occasionally glucagon, to regulate their blood glucose, which is critical to lower their risk of long-term complications such as blindness, kidney failure and cardiovascular disease.
When managing diabetes, many patients must vigilantly test blood glucose with a glucose meter, calculate insulin doses, and administer necessary insulin doses with a needle or insulin infusion pump to lower blood glucose. Glucagon may be injected in an emergency to treat severe low blood glucose. Some patients benefit from additional monitoring with a continuous glucose monitoring system.
The FDA is collaborating with diabetes patient groups, diabetes care providers, medical device manufactures, researchers, and academic investigators to foster innovation by clarifying agency expectations for clinical studies and product approvals. These efforts have accelerated the development of the first hybrid closed loop system, the Medtronic's MiniMed 670G

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Rank: 7
Score: 68.211555
Retrieved Text: Melandia in her home town of Fairhaven, Mass.
Melandia Coutinho may be the only 10-year-old who can talk about Harry Potter and the American Revolution in the same breath. She takes Portuguese, plays on two soccer leagues, and she still has energy for homework and climbing trees with her younger brother Marcio.
Melandia was referred to endocrinologist Dr. Gregory Goodwin of Boston Children’s Hospital. Within hours of the physical, soccer was cancelled, Marcio was with his grandparents, and Chanda, Jeff and Melandia were packed and on their way to Boston.
Type 1 diabetes is a chronic condition in which the body produces little or no insulin. If managed properly, a child with Type 1 diabetes can maintain a very healthy, active lifestyle, but it takes work and can be overwhelming for families.
Melandia’s blood glucose numbers were steady enough at that point that she stopped needing insulin injections. Instead she began receiving insulin through a pump: a small, computerized device programmed to deliver insulin directly into her body.
Goodwin made small adjustments to Melandia’s insulin intake and additional changes again a week later to lower her blood sugar.
For Melandia’s latest two appointments and any other followups going forward, the drive to see Goodwin is much shorter. With the opening of a new facility at Boston Children’s at North Dartmouth—seven miles from the Coutinho’s home on the south coast—expanded services have become available, including continuing care for return diabetes patients.
With two years of diabetes management under her belt and her blood sugar levels down, 10-year-old Melandia is thriving.
She recently started fifth grade

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Rank: 8
Score: 67.99882
Retrieved Text: Dealing with gestational diabetes, a glucose intolerance diagnosed during pregnancy, requires a careful balancing act.
Gestational diabetes is glucose intolerance diagnosed while a woman is pregnant, usually late in the second trimester or in the third. The disease, like other forms of diabetes, affects how the body handles sugar, and the result in this case is that too much sugar remains in the bloodstream. Gestational diabetes raises the risk of complications during delivery.
In normal digestion, the sugar molecule glucose-an important source of energy-is absorbed into cells with the help of insulin, produced by the pancreas gland. During pregnancy, the placenta secretes a hormone called human placental lactogen to protect the foetus and make sure it receives enough energy even if the mother fails to.
Gestational diabetes raises the risk of complications during delivery.
The hormones make it harder for the mother's cells to absorb glucose because they raise her resistance to insulin. Thus, too much sugar may stay in her blood. Her insulin resistance may increase during pregnancy as the placenta grows and produces more of the offending hormones.
Rhonda Bentley-Lewis, MD, an endocrinologist at Harvard Medical School and Brigham and Women's Hospital, says that about 4% of pregnant women are diagnosed with gestational diabetes. Its prevalence can range from 1 to 14%, depending on risk factors.
Women at risk include those who are over 25, overweight before pregnancy, have first-degree relatives with type II diabetes (the most common form, in which either the body does not produce enough insulin or the cells ignore the insulin), and who have had gestational

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Rank: 9
Score: 67.76207
Retrieved Text: Rob Varela /Ventura County Star: Jennifer Mueller, center, walks in Marina Park in Ventura with her parents Kristy and Don Schadt and their dogs Nicholas and Patches to check out a possible route for their upcoming doggie-thon fundraiser on June 29.
Struggling for 18 years with type 1 diabetes, Jennifer Mueller has inspired a benefit to support Heaven Scent Paws, a nonprofit that trains dogs to know when their owners' blood sugar is ready to drop — a life-saving skill that even the most sophisticated monitors cannot detect.
"Many type 1 diabetics have severe complications and difficulty managing their diabetes from the beginning of their diagnosis," said Mueller, 33, of Oak View. "Diabetic service dogs can help us manage our diabetes significantly."
For Mueller and others with type 1 diabetes, managing the disease is a full-time job.
"When my diabetes is uncontrolled, it's a horrible feeling of powerlessness and frustration," she said. "I feel scared that I might die or have an episode in public."
Diagnosed with it at 15, she said she believes that having a service dog will help her manage the disease much better.
"Since I have hypoglycemia unawareness, a service dog can help me significantly with that; the dogs can smell the change in your body well before your blood sugars begin to drop and then alert me," Mueller said.
"I will be able to sleep at night without the fear of not waking up," she said. "This dog will help me regain confidence that I can go about my life as normally as possible again, with the assistance

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Rank: 10
Score: 66.838806
Retrieved Text: A leading endocrinologist shares new advances in managing this chronic — and common — feline disease. Hint: Weight control is your best weapon.
Diabetes mellitus is on the rise among cats in the United States, according to a survey of clinics nationwide — an increase that has been correlated with a rise in obesity. Although it’s hard to draw definitive conclusions from the results of the survey, there’s no question that feline weight control is a key to preventing this chronic disease.
Most cats with diabetes will require twice daily insulin injections.
There are two main categories of diabetes in humans. Type 1 is, in essence, an autoimmune disease that causes the body to attack and destroy insulin-producing beta cells in the pancreas. It’s manageable with injections of insulin, but it’s not reversible.
In the much more common type 2, typically seen in overweight adults and, increasingly, among obese children, the pancreas still produces insulin, but either it does not produce enough or the body is resistant to the insulin it does produce. If it hasn’t progressed to a dangerous stage, type 2 diabetes can often be controlled by diet and oral medications.
Type 2 is the variety to which cats are usually subject, but by the time most cats are diagnosed, the disease is fairly advanced. This means that they are likely to be insulin dependent for the rest of their lives, according to Dr. Mahony, who is board certified by both the American and European Colleges of Veterinary Internal Medicine.
Many of the same factors that come into play in

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Rank: 11
Score: 66.76677
Retrieved Text: You might not think of a Type 1 diabetes diagnosis as a positive thing, but for Jeannie Williams, a consultant at the Jackson location of Medical Weight Loss Clinic, it’s exactly that.
She acknowledges that diabetes has affected her life in various ways, but believes it has helped her life for the better. Since November is National Diabetes Month, we’re exploring why.
“From a young age, I had to learn and understand how foods, illness and just simple everyday life choices impact our bodies,” Jeannie says.
It even helps her in her work, because it helps her closely relate to her patients.
Jeannie, who is now 32, was diagnosed with the autoimmune disease when she was 9 years old.
She manages her diabetes with three to five insulin injections per day, along with following a healthy diet. Fortunately, there have been improvements in managing Type 1 over the two decades she has lived with the disease. Jeannie says she has a much easier time scheduling injections and managing her blood sugar levels thanks to that progress.
Jeannie believes that there are misunderstandings around Type 1 diabetes as well as how it differs from Type 2.
Meanwhile, with Type 2 diabetes, the body doesn’t use the insulin it produces effectively, so the pancreas tries to compensate by producing more. However, the body is essentially insulin resistant. Type 2 can be controlled and even reversed through a healthy diet and exercise, medications and sometimes insulin injections.
In addition, Type 1 cannot be prevented, but there are several factors that make someone at risk for Type 2

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Rank: 12
Score: 66.6736
Retrieved Text: Type 1 diabetes: Insulin-dependent diabetes, juvenile diabetes, or early-onset diabetes—the body produces little or no insulin because the pancreatic cells that make insulin stop working. This results in high blood sugar.
Type 2 diabetes: Insulin resistance is the most common type of diabetes, occurring most often in adulthood and often among people with obesity. Over time, as the body repeatedly secretes insulin in large quantities, the cells become less sensitive and no longer respond to insulin the same way. When this happens, the cells do not get fed and blood sugars rise to dangerous levels.
Gestational diabetes: Affects women during pregnancy and results in progressively rising levels of glucose.
Type 1 diabetes often requires daily injection with insulin since your body does not produce the insulin needed to absorb blood glucose.
Type 2 diabetes means your body produces insulin, but does not react to it correctly so you need an oral medication to help regulate insulin. Together with proper nutrition and exercise, weight loss can also help manage blood glucose levels.
A complete physical along with your full medical history: measure your height, weight, blood pressure, check your mouth, eyes, abdomen, take your pulse, look at your hands and fingers and feet, listen to your heart and lungs, check your skin—especially where you inject insulin, test your reflexes, check dates of how and when you are diagnosed with diabetes, discuss past lab test results, discuss your eating habits, exercise levels, discuss current treatment plan and any incidence of infections or ketoacidosis, or low blood sugar reactions, discuss complication, other medicines you

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Rank: 13
Score: 66.482834
Retrieved Text: My first pregnancy was pretty good, I had no problems. Now I'm having my second pregnancy and am 33 weeks. Last week my doctor checked my blood sugar and it was 210 mg/dl.
She advised to make some changes on my diet, to do more exercise, and gave me insulin shots.
I didn't want to go for insulin, I started my diet changes and exercise, and now my sugar levels are ok as my doctor said.
I want to know why did happen gestational diabetes second pregnancy while everything was ok with the first pregnancy? Has anything I've eaten or done cause me to have diabetes?
One last thing: I've heard about this acclimation or adaption during pregnancy. How far do they affect me and my baby?
Usually, gestational diabetes begins when your body is unable to produce and utilize its need from insulin during pregnancy, this means that glucose can’t be properly used by your body to produce energy; glucose will actually remain high in your blood (hyperglycemia); raising the results of your oral glucose tolerance test.
•	Being obese; you might have gained excess weight after your first pregnancy and failed to regain your normal weight before the second one.
•	Finally, gestational diabetes tends to occur more frequently in African Americans, Latino Hispanic, Native Americans Pacific Islanders individuals.
My sister had got gestational diabetes when she was pregnant, after delivery was cured from her GDM, but her doctor advises her to adopt healthy dietary habits, have regular physical exercise, and avoid excess sugars for the rest of her life to avoid developing type

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Rank: 14
Score: 66.03368
Retrieved Text: Type 1 Diabetes and how it happens? Let’s dig deeper. What does diabetes mean anyway? Well, it just means that the blood sugar is too high. This blood sugar is also called glucose.
And how can we get rid of glucose? Where does it come from? Well, it comes from the food we eat and no, we should not get rid of it altogether for we need it for energy. We just need to have the right amount in the right place.
What is one to do? With Type 1 or Type I Diabetes, it looks like we are between a rock and a hard place. Don’t worry, we will show you what to do later. Meantime watch how this courageous boy deals with his type 1 diabetes.
Type 1 Diabetes used to be known as juvenile diabetes or insulin-dependent diabetes because it seemed to occur in children and adolescent. This is also usually seen in young adults when the cells that produce insulin in the pancreas are destroyed.
How are these cells destroyed in Type 1 or Type I Diabetes, you asked? Well, the body immune system attacked and destroyed these cells. As a result, these cells cannot get the glucose they need.
There is something new you ought to know about this so-called juvenile-onset diabetes or Type 1 Diabetes. Now the authorities are saying it does not only appear in children. Why? Because they have seen it appearing at anytime in life.
After you're done going over the book there, make sure you click the back browser button to come

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Rank: 15
Score: 66.01685
Retrieved Text: My daughter is being treated by an endocrinologist for hypothyroidism. She has what looks like 'dirty skin' around her neck. The doctor said this is a sign of insulin intolerance and that she is borderline diabetic. What is insulin intolerance and is this 'dirty skin' look a symptom?
A state in which a given level of serum insulin produces a less than expected biological effect. Patients may vary from normoglycemic to severely diabetic despite large doses of insulin. Many people with Type 2 diabetes produce enough insulin, but their bodies do not respond to the action of insulin. This may happen because the person is overweight and does not respond well to insulin. Also, as people age, their body cells lose some of the ability to respond to insulin. Insulin resistance is also linked to high blood pressure and high levels of fat in the blood (see Syndrome X).
Another kind of insulin resistance may rarely happen in people who take insulin injections. They may have to take very high doses of insulin every day (e.g., 200 units or more (in adults) to bring their blood glucose down to the normal range. This has also been called "insulin insensitivity."

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Rank: 16
Score: 65.97824
Retrieved Text: When your child or teen is diagnosed with diabetes it means that your body does not produce insulin or insulin does not handle well. The diagnosis of type 1 diabetes means your pancreas does not produce insulin. When diagnosed with type 2 diabetes means that your body is not using insulin properly.
Insulin is the hormone secreted by the pancreas whose function is to transport blood glucose into body cells to be used as energy stream.
Without insulin levels blood sugar rise and your body begins to use fat as an energy source.
It is known as ketoacidosis when the patient metabolizes body fat rather than glucose due to insulin deficiency.
The main cause of diabetes ketoacidosis is that it has not been well controlled.
Your child or teen may be taking the wrong dose of insulin or diabetes medication, or have forgotten to take your dose.
If your child is sick, your body is suffering from an infection, has been surgically intervened or has had an accident that causes physical pain, blood glucose rises. If you are young and in the days of her menstrual period, also sugar may go up.
Ketoacidosis can also be, in many cases, the first sign that your child or teen is suffering from diabetes when not yet been detected with medical tests.
When the body breaks down fats it produces chemicals known as ketones. Ketones or acids produced accumulate in the blood and urine.
For the diagnosis of ketoacidosis will be made a quick urine test using a test strip with chemicals that react with ketone bodies in

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Rank: 17
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Retrieved Text: Susan Boyle, the immaculate songstress, has been standing out as truly newsworthy with h susan boyle weight loss transformation.
She has lost an astounding 50 pounds! Obviously, she looks slimmer and more advantageous than at any other time. Boyle previously showed up on TV in 2009 when she was a competitor on Britain’s Got Talent.
Her voice inspired the three judges as well as right away contacted a huge number of hearts. Today, she is an incredibly famous artist, has discharged 7 collections, and her assessed total assets is about $35 million. Peruse on to get the total picture of how everything began, and how susan boyle weight loss.
Susan Boyle is a Scottish singer who was born on 1st April, 1961. A singer for her whole life, was discovered in 2009 when Susan Boyle audition for Britain’s Got Talent.
She sang “I Dreamed a Dream” from Les Miserables. She released her first album in November 2009, which became the bestselling debut album of all the time in UK.
The album also topped the Billboard 200 chart for six weeks straight, and Boyle made £5 million. But what encouraged her to lose weight? Let’s find out next.
Susan Boyle had been struggling with her weight since her childhood. In fact, she was regularly bullied for being overweight and what she looked like.
In any case, it was simply after she was diagnosed with type 2 diabetes in 2012 that she decided to start living a healthy life.
Diabetes keeps the cells from taking up glucose and converting it into usable vitality. It happens either

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Retrieved Text: Type 2 diabetes affects a large number of people all over the United States. Approximately 30 million people in the United States have diabetes, according to the American Diabetes Association. And 1.5 million of them are diagnosed each year.
Treating type 2 diabetes isn’t a one-step approach. Lifestyle changes and physical activity can help people with diabetes manage their blood sugar levels. Also, medications like basal insulin therapy can help improve quality of life. It can also help people with diabetes avoid long-term complications.
Find out what basal insulin is and why your body needs it to have a healthy blood sugar level.
Basal insulin is also called “background” insulin. The name describes the insulin released throughout the day to provide 24-hour coverage while fasting. Insulin allows glucose to go from the blood into the cells to use as energy and reduce excessive glucose production by the liver.
Basal insulin also helps the body store fats and sugar for use between meals and overnight. It differs from “bolus” insulin, which is released in response to meals.
People with type 1 and type 2 diabetes may have a problem making enough or any insulin. The liver pumps out glucose throughout the day. And a lack of basal insulin elevates blood sugar levels. This happens even during fasting periods like overnight.
Diabetes management uses basal insulin therapy as part of the physiological approach to managing blood sugar levels. Endocrinologists commonly prescribe long-term or intermediate acting insulin to mimic the action of basal insulin. This insulin is used together with a short- or rapid-acting insulin.

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Retrieved Text: Here’s a primer on the disease, its effects, the struggle to live with it, and the efforts to treat it.
Lee Alexander uses an insulin pump that communicates with her glucose monitor to track blood sugar levels.
For over four decades, Lee Alexander has struggled with Type 1 diabetes, an autoimmune disease in which the body mistakenly turns on itself, decimating insulin-producing cells in the pancreas.
Unable to make this vital hormone on her own, the Orlando resident depends on synthetic insulin to survive. Without daily doses, her blood sugars, or glucose, can dip too low or spiral too high. Changes in either direction carry imminent threats, some life-threatening, experts say, while sky-high sugars over time can lead to heart or kidney disease, blindness and even limb amputation.
So, 50-year-old Alexander monitors her glucose levels at least five or six times a day, just as she has since age 7, when doctors first diagnosed her. Taught back then to watch for color changes in urine, “I knew which colors to shoot for,” she says with a laugh. A blue paper meant blood sugars were too low; blood-orange colors meant they had jumped too high; but “greens were always good,” keeping pace with her growth and energy needs as a child.
The treatment scenario differs for those diagnosed with Type 2 diabetes, however—a far more prevalent form of the disease, closely linked to obesity and physical inactivity.
In Type 2 diabetes, the pancreas still pumps out insulin, but “there’s too much sugar on board,” Kaplan says, because the pancreas makes too little of

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Retrieved Text: Diabetes is a chronic disease in which the body either cannot produce insulin or cannot properly use the insulin it produces. Insulin is a hormone that helps glucose enter the body's cells, where it is used for energy. Diabetes therefore causes blood glucose (sugar) levels that are too high.
Type 1 diabetes, sometimes called Juvenile Diabetes, usually develops in childhood, adolescence, or early adulthood. About 10% of those with diabetes have type 1 diabetes. With type 1 diabetes, the body produces very little or no insulin. Type 2 diabetes is the most common form of diabetes (90%), and it usually occurs in adults, but children can be affected as well. With type 2 diabetes, the body does not make enough insulin or is unable to use it properly.
The symptoms below occur when blood glucose levels exceed the normal range. They may or may not be present when a diagnosis of diabetes is made, and they may also occur when a person's diabetes is not well controlled. If you have any of these symptoms, it is important to contact your doctor.
The exact cause of type 1 diabetes is not yet known. However, having a family member (parent, sibling) with type 1 diabetes slightly increases the risk.
Diabetes is diagnosed through a blood glucose test that measures the amount of glucose (sugar) in a sample of blood. Glucose is measured using millimoles per litre (mmol/L). Levels that exceed those outlined in the table below are indicative of diabetes.
The goal of diabetes treatment is to keep blood glucose levels as close

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Retrieved Text: The world is plagued by disease. Between heart disease, allergies, diabetes, and cancer, we all seem to know someone who’s health causes them anxiety and frustration.
ToMarah Hutton found out first-hand how a change in health can affect quality of life.
ToMarah was living what most of us would consider a typical life. She was a busy mom, focused on her family and responsibilities. She knew that her health wasn’t perfect, but she wasn’t terribly worried about it. That is, until a few strange symptoms sent her to the doctor for a check-up. The diagnosis was one that about 30 million other Americans have heard – type 2 diabetes.
Symptoms of diabetes include sweating, shaking, fast heartbeat, blurred vision, dizziness, and tingling hands or feet, all caused by irregular blood sugar levels. When the body is either unable to produce enough or properly use insulin (a hormone that carries sugar from the blood stream to cells throughout the body) blood sugar levels can dangerously fluctuate.
Researchers also believe there is a genetic link that makes some more susceptible to the disease than others .
ToMarah knew she had put on some weight, but what mom doesn’t? She didn’t always buy organic, but who can afford to? Exercise wasn’t her main hobby, but who has time?
Like so many of us, ToMarah believed she was doing just enough to keep herself healthy. But with her diabetes diagnosis, she realized she had let her health slip away from her and wondered if it was too late to do anything about it.
Cardiovascular disease. Those with

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Retrieved Text: Prior to my seven year old daughter's diagnosis of type 1 diabetes (about a year and a half ago), she did very well in school, but now the teacher says she just stares off into space when she's supposed to be doing her work, and her grades are dropping. She's very moody, and her sugar has been going up before lunch even if she hasn't eaten much breakfast. Can her diabetes be affecting her schoolwork? She says her eyes get tired. I filed for SSI, and they told me that sometimes the way a child deals with an illness is a disability within itself. Can the way she's dealing with diabetes, affect her schoolwork?
There is growing evidence that changes in blood glucose do affect how children with type�1 diabetes concentrate in school. No doubt low blood glucoses (hypoglycemia) are important, but new studies give new light to how elevated blood glucoses (hyperglycemia) affects school work. You don't indicate what her insulin regimen is but if she is getting higher readings at lunch time, this suggests that she needs more fast-acting insulin in the morning. If she eats a mid-morning snack, then I will presume she is on Regular with breakfast and this may need to be increased. If she does not receive a mid-morning snack, then I presume she is on Humalog or Novolog at breakfast. Discuss your daughter's insulin regimen and meal plan with her diabetes team."Smoothing-out" her glucose readings may do her a lot of good. Also, consider asking her teachers for an IEP

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Retrieved Text: Back in October, Nicole had to be pushed into the dialysis clinic in a wheelchair. Today, eight months later, she can take 60-minute walks outside without any assistance. We’ve been talking in this e-letter about how the Buteyko Breathing Method has helped her deal with the many complications and ride-along ailments of type-1 diabetes. But fundamental to the Buteyko Breathing Method is one simple technique… nasal breathing.
Nicole switched to exclusively using her nose to inhale and exhale. Coughing and talking are some exceptions to the exhale part of the equation. But, on the whole, she switched to using her nostrils to breathe, instead of her mouth, 24/7. We saw immediate improvements.
1. Improved Blood Circulation = Greater Insulin Perfusion: Nasal breathing reduces the amount of CO2 leaving the lungs. This increases the CO2 levels in the blood. Higher CO2 levels cause the blood vessels to expand. This allows injected insulin to circulate better, resulting in more predictable blood sugar with smaller dosages.
3. More Oxygen = Less Need for Insulin: Breathing out through the nose causes exhaled air to be trapped in the nasal cavity. Thus, inhaled air is mixed with exhaled air. This further increases the CO2 content of the lungs and blood. The more CO2 in the lungs and blood, the more oxygen is released by heamglobin into the body tissues. Oxygen is needed to burn glucose to produce energy. Therefore, it would appear, the more oxygen available, the less glucose in the blood.
Back in October, when Nicole was very unwell, I remember seeing her napping

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Retrieved Text: When Lilly Jaffe, 6, gleefully disconnected her insulin pump from her hip last month, her mother, Laurie, forced herself to be brave.
Lilly was cutting the lifeline to the hormone that had kept her alive since she was a month old. That was when she was diagnosed with Type 1 diabetes, meaning she would always need insulin injections.
But thanks to advances in molecular medicine, doctors had reason to believe that Lilly could be weaned off the shots. Because scientists recently had identified the genetic mutation that causes her condition, they knew why her body was not making insulin and they had a way to fix it: a readily available drug.
Now Lilly no longer needs insulin shots to control her blood sugar. Instead, she takes five sulfonylurea pills twice a day.
"Our family is watching a miracle unfold," Jaffe said. "For me, the simple act of removing the battery from her pump and putting it away in a drawer was surreal."
The kind of diabetes Lilly has is rare, so the discovery will help relatively few children. But scientists say it is an example of how genetic discoveries are beginning to allow doctors to treat the root causes of a disease instead of its symptoms.
And for families like Lilly's, the benefit is life-changing.
"We could never let our guard down, having to monitor her closely and constantly," said Jaffe, who lives in the north suburbs. "That meant glucose checks 10 times a day, even at night, and three to five daily insulin injections, not to mention analyzing every bite she ate."
Two

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Retrieved Text: Type 1 and type 2 diabetes both occur when the body cannot properly make, store and use glucose, which is essential for energy. It can lead to severe complications if sugar accumulates in the blood without getting to the cells that need it.
Type 1 diabetes occurs when the immune system attacks the pancreatic beta cells so that they can no longer make insulin. Type 1 diabetes is often hereditary and cannot be prevented.
Type 2 diabetes is more common in older people age, but many children are now starting to develop it. This type of diabetes occurs when the pancreas produces insulin, but the body cannot effectively use it. Lifestyle factors appear to play a role in its development.
damage to blood vessels and organs.
Type 1 and type 2 have different causes, but they both involve insulin. Insulin is a hormone produced by the pancreas to control the way blood sugar converts to energy.
Researchers suspects that for type 1 diabetes, the immune system mistakenly attacks the pancreatic beta cells, which produce insulin. The cause of this is yet unknown, however, childhood infections may play a role.
The immune system destroys these cells, making it difficult for the body to make enough insulin to control blood glucose levels. A person with type 1 diabetes will need to use supplemental insulin from the time they receive the diagnosis and for the rest of their life.
Type 2 diabetes occurs when the cells of the body begins to resist the effects of insulin. The body will stop producing enough insulin over time, so

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Retrieved Text: Gestational diabetes, or diabetes that occurs in the second and third trimester of pregnancy and resolves at birth, occurs in approximately 9.2 percent of pregnancies in the United States. Gestational diabetes is defined as impaired glucose tolerance with onset or first recognition during pregnancy. It occurs in women who have never had overt diabetes before but who develop high sugar levels during pregnancy.
While gestational diabetes can be an alarming complication, it can be controlled by maintaining a healthy diet, exercising, and taking medication if needed.
A mother’s blood glucose levels usually return back to normal after delivery. However, she should be closely monitored by her health care provider.
You will probably be tested for gestational diabetes between weeks twenty-four and twenty-eight of your pregnancy, using an oral glucose tolerance test to see how well your body responds to ingesting a large amount of glucose.
If you have a higher risk of gestational diabetes, your doctor may test you earlier, at your first visit during your pregnancy.
For most women, gestational diabetes doesn’t cause any symptoms. However, gestational diabetes screening is part of normal prenatal care.
Your doctor will evaluate your risk factors for gestational diabetes early in your pregnancy. If you have risk factors for gestational diabetes, your doctor will evaluate when screening is right for you.
Routine screening for gestational diabetes involves an oral glucose test. The test involves drinking a sweetened liquid, called Glucola, which contains 50 grams of glucose, also known as 50g OGTT. How the body metabolizes this solution is measured by a blood test.
A blood sugar level

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Retrieved Text: Jen Mackenzie has lived with type-1 diabetes since she was four, and is only too well aware of the symptoms of the disease.
So when her normally vibrant two-year-old daughter, Erin, suddenly seemed drained of all energy, it raised alarm bells.
‘Erin had also wet the bed twice that week — her nappy and the mattress were totally sodden,’ says Jen.
The next day Jen took her toddler to the GP and mentioned her worry about diabetes.
Yet rather than give Erin a simple blood test to check her blood sugar levels, the doctor made Jen feel as though she was wasting her time, and sent her away ‘with a flea in her ear’.
‘I stood in the reception sobbing — Erin was clearly not right, she was really lethargic and quiet,’ says Jen, 35, who is a full-time mother to her three daughters — Erin, now five, Faith, six, and Harriet, nine.
The receptionist called the surgery nurse, who gave Erin a blood test.
Jen’s hunch was right — not only was Erin’s blood sugar raised, a key sign of type-1 diabetes, but she also had raised levels of ketones, a sign her insulin level was so low her body was producing the dangerous toxic by-product.
‘The GP apologised. There was no malice in what she had done — I just don’t think she could fathom that this toddler could be old enough to have type-1 diabetes,’ says Jen, who lives in Folkestone, Kent, with her husband, Stuart, 37, a loft insulator.
Erin was taken to hospital and remained there for five days while

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Retrieved Text: Blood glucose regulation is a dynamic process. The art of successful management of diabetic pets is to use exogenous insulin to mimic this dynamic process of blood glucose regulation.
Human labeled insulin has evolved from animal to recombinant to synthetic sourced insulins with variable potency and duration of action. This allows the physician to deliver insulin more precisely and manage diabetes more intensely.
Animal patients may tolerate extremes in blood glucose better than humans and are unable to signal when their blood glucose is low. Veterinarians have the flexibility to manage their patients’ disease tightly with the goal of achieving normal blood glucose or more loosely with the goal of managing clinical signs and reducing the risk of diabetic ketoacidosis.
Veterinarians and their patients are dependent on pet owners’ participation in treatment. Clients’ ability to care for pets can be constrained by budget, time and commitment level. Thus it is imperative to establish a goal for treatment which meets clients’ expectations as well as patients’ medical needs. Realistic treatment goals are to eliminate clinical signs and stabilize body weight while avoiding hypoglycemia.
It is well established that it is possible to induce remission in cats with diabetes with a combination of insulin therapy, diet change and aggressive monitoring. Attempting to induce remission of diabetes in a feline patient is academic at best; if the client does not have the time or resources to monitor blood glucose levels frequently at home. Conversely, the highly motivated cat owner may be left dissatisfied and turn to the internet if she is not offered

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Retrieved Text: According to Hersen (1998) diabetic children usually have the type 1 diabetes, also referred to as juvenile diabetes. The other type of diabetes is known as type 2 and is common among older people. In this case Hannah is only ten years and therefore her type of diabetes is the type 1.Therefore, we are going to look at what diabetes mellitus in juveniles entails like in the case of Hannah, the symptoms, cause, and the appropriate treatment for the condition plus the teachings that are likely to help Hannah in her recovery process and all the potential barriers that may be experienced in the therapy processes.
Diabetes mellitus is a condition whereby the body has difficulty regulating the blood sugar levels. There are two types of diabetes namely, type 1diabetes which is also referred to as juvenile diabetes or insulin dependent diabetes and type 2 diabetes. In this case study we are going to look at diabetes type 1which is common in juveniles like Hannah in the case study. This condition present when the immune system of the body attacks and kills the beta cells in the pancreas. These cells are usually responsible for the production of insulin. Insulin is a hormone that aids the body to transfer the glucose that is contained in the food to the body cells all over the body for provision of energy. Therefore, in a case where the beta cells are damaged, insulin is not produced making the glucose remain in the blood system where if no precaution is taken, it

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======= Instance Index 82 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are Sally or Sue ):

Electrons at lower energy levels, which are closer to the nucleus, have less energy.


Sally has an electron. Sue has an electron that is farther from the nucleus. Whose electron has lower energy Sally or Sue?

Target Text: Sally

#### Retrieved Documents ####

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Retrieved Text: The Aufbau model lets us take an atom and make predictions about its properties. All we need to know is how many protons it has (and how many electrons, which is the same as the number of protons for a neutral atom). We can predict the properties of the atom based on our vague idea of where its electrons are and, more importantly, the energy of those electrons.
How electrons fill in their positions around an atom is called the Aufbau Process (German: "building-up" process). The Aufbau Process is all about keeping electrons at their lowest possible energy and is the direct result of the Pauli Exclusion Principle. A corollary of Coulomb's law is that the energy of an electron is affected by attractive and repulsive forces. The closer an electron to the nucleus, the lower its energy. The closer an electron is to another electron, the higher its energy.
Of course, a basic principle of thermodynamics is that a system will proceed to the lowest energy possible. That means, if an atom has only one electron, the electron will have quantum numbers that place it at the lowest possible energy. It will be as close as possible to the positive nucleus.
If an atom has a second electron, it will also be as close as possible to the nucleus. It could have the same quantum numbers as the first electron, except for spin. There is a trade-off, of course, because those two electrons will be close enough to repel each other. However, if it is a choice between

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Retrieved Text: `●` Shapes of Atomic Orbitals.
`●` Nodal surface or Node .
`=>` According to Max Born, the square of wave function(i.e, ` psi^2`) at a point gives the probability density of the electron at that point. Fig 2.12(b).
`=>` For 1s probability density is maximum at the nucleus and it decreases sharply as we move away from it. But for 2s orbital the probability density first decreases sharply and again starts increasing. After reaching a maxima it decreases again and approaches zero as the value of r further increases.
The region where the probability density function reaches to zero.
This gives fairly good representation of the shapes of the orbitals.
In this, a boundary surface or contour surface is drawn in space for an orbital on which the value `|psi|^2 ` is constant.
Definition : For a given orbital, only that boundary surface diagram of constant probability density is taken which encloses a region or volume in which the probability of finding the electron is `90%`. fig [2.13 (b)].
Note : - We do not draw boundary surface diagram of `100%` probability because ` psi^2` has always some value at any finite distance from the nuclues, so it is not possible to draw a boundary surface diagram of a rigid size of `100%` probability.
For `s`-orbital, boundary surface diagram is spherical in shape. i.e the probability of finding the electron in all direction is equal.
For `p`-orbital (Fig 2.14), the boundary surface diagram is not spherical. But it has two lobes which are on either side of the plane passing through the nucleus. At this plane,

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Retrieved Text: Following the work of Ernest Rutherford and his colleagues in the early twentieth century, the picture of atoms consisting of tiny dense nuclei surrounded by lighter and even tinier electrons continually moving about the nucleus was well established. This picture was called the planetary model, since it pictured the atom as a miniature “solar system” with the electrons orbiting the nucleus like planets orbiting the sun. The simplest atom is hydrogen, consisting of a single proton as the nucleus about which a single electron moves. The electrostatic force attracting the electron to the proton depends only on the distance between the two particles. The electrostatic force has the same form as the gravitational force between two mass particles except that the electrostatic force depends on the magnitudes of the charges on the particles (+1 for the proton and −1 for the electron) instead of the magnitudes of the particle masses that govern the gravitational force. Since forces can be derived from potentials, it is convenient to work with potentials instead, since they are forms of energy. The electrostatic potential is also called the Coulomb potential. Because the electrostatic potential has the same form as the gravitational potential, according to classical mechanics, the equations of motion should be similar, with the electron moving around the nucleus in circular or elliptical orbits (hence the label “planetary” model of the atom). Potentials of the form V(r) that depend only on the radial distance r are known as central potentials. Central potentials have spherical symmetry, and so rather than specifying

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Retrieved Text: principle that relates to electron energies.
separation for two atoms or ions.
separation and the bonding energy.
hydrogen, and van der Waals bonds.
protons and neutrons within the nucleus.
atomic masses, which are called isotopes.
 Electrons are assumed to revolve around the atomic nucleus in discrete orbitals, and the position of any particular electron is more or less well defined in terms of its orbital.
 Another important quantum-mechanical principle stipulates that the energies of electrons are quantized; that is, electrons are permitted to have only specific values of energy. An electron may change energy, but in doing so it must make a quantum jump either to an allowed higher energy (with absorption of energy) or to a lower energy (with emission of energy). Often, it is convenient to think of these allowed electron energies as being associated with energy levels or states. These states do not vary continuously with energy; that is, adjacent states are separated by finite energies.
- values of energy that are permitted for electrons.
 Bohr model was eventually found to have some significant limitations because of its inability to explain several phenomena involving electrons. A resolution was reached with a wave- mechanical model, in which the electron is considered to exhibit both wavelike and particle-like characteristics. With this model, an electron is no longer treated as a particle moving in a discrete orbital; but rather, position is considered to be the probability of an electron’s being at various locations around the nucleus. In other words, position is described by a probability distribution or electron cloud.
 Using wave mechanics,

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Retrieved Text: An orbital is a region in space where there is a high probability of finding electron.
A wave function represents an electron is the product of two parts, a radial part and an angular part. The square of the radial part of the wave function indicate the probability of finding the electron at any distance r from the nucleus. The square of the angular part of the wave function gives the probability of finding an electron in a particular direction from the nucleus. The radial dependence and angular dependence of wave function taken together, tell us that a three dimensional standing electron wave (orbital) can be picture to have size, shape, and an orientation of an orbital.
Principal Quantum Number ( n ).
The Orbital angular momentum quantum Number or Azimuthal Quantum Number ( l ).
The Magnetic Quantum Number (ml ).
The Principal quantum Number(n) is of primary importance in the determining the size and hence the energy of an electron.
For hydrogen the energy is fixed by the value of n. In other multi electron atom, the energy of each electron depends on the value of the principal quantum number of the electron. As the value of n increases the radius (nucleus electron separation increases that is the size of the orbital increases).
The energy also raised, n is always an integer and can assume the value,1,2,3,4.... but not zero.
The general geometric shapes of an electron wave (Orbital) is described by the Azimuthal Quantum Number.
This quantum number related to for the electron in that state.
Therefore an electron having principal quantum number

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Retrieved Text: How many neutrons are present in the nucleus of one atom of ?
From the periodic table, we find that the atomic number, i.e., the number of protons in the nucleus of is 15. Given that the mass number is 32, and recalling the formula which relates mass number to the number of neutrons and protons: , we find that the number of neutrons in the nucleus of one atom of is 17.
Which atomic symbol represents a period five transition metal that has 42 electrons when it forms a cation?
Transition metals extend from groups 3 through 12 and periods 4 through 7. Ru, in its neutral state, has 44 electrons. Therefore, when it becomes a cation, it will have 42 electrons.
What is the mass number, atomic number, and charge, of the isotope of an atom that contains 34 protons, 36 neutrons, and 36 electrons?
The atomic number is equal to the number of protons in the element, so from the periodic table, we find that the element with atomic number 34 is selenium. Since , we calculate that the mass number is 70. Lastly, there are two more electrons than protons, so the charge will be .
Which of the following organizes the forces from strongest to weakest?
Covalent bonds are by far the strongest, requiring to be broken.
Next are hydrogen bonds, which require between to be broken.
Next are dipole-dipole interactions, which require to be broken.
Finally, van der Waals forces are the weakest of those listed, requiring to be broken.
Which of the following electron configurations indicates an atom in an

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Retrieved Text: You will place electrons in the appropriate energy levels outside of an atom.
Explain that an atoms outermost electrons are responsible for an elements reactivity.
Identify the electron arrangement within atomic energy levels.
Explain that an electrons energy is related to its distance from the nucleus.
An atom has three subatomic particles: the proton, the neutron, and the electron. The proton has a positive charge, is located in the nucleus and is responsible for an atom's identity. The number of protons does not change in an element, and is equal to the atomic number on the periodic table. Neutrons are also located in the nucleus, but have no charge.
The electrons are located outside the nucleus, and have a negative charge. The electrons will arrange themselves into specific energy levels, starting with the level closest to the nucleus. Each energy level has a maximum number of electrons it can hold: two in the first, eight in the second, 18 in the third and 32 in the fourth. As the distance of the energy level from the nucleus increases, so does the energy the electrons contain.
The arrangement of the electrons in their energy levels is called the "electron configuration." In a neutral atom, the number of electrons will be the same as the atomic number, or number of protons. For learners to place the electrons in the appropriate energy level, they should identify the atomic number, and start placing the electrons in energy levels, the closest to the nucleus first. Once the energy level has its maximum number of electrons, they should

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Retrieved Text: Therefore,Ne has the most positive electron affinity value Br and has the most negative electron affinity value among the given elements. Potassium has a more positive electron affinity value than phosphorous, since electron affinity decreases from top to bottom and increases from left to right in periodic the table. how to find last action on mac The electron affinity of an element is a measure of that element’s tendency to act as an oxidizing agent (an electron acceptor) and is generally related to the nature of the chemical bonds the element forms with other elements.
Which has the more negative electron affinity br or br?
The electron affinity is a measure of the attraction between the incoming electron and the nucleus - the stronger the attraction, the more energy is released. The factors which affect this attraction are exactly the same as those relating to ionisation energies - nuclear charge, distance and screening.

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Retrieved Text: If electrons are held in orbit by electromagnetic attraction to nuclei, shouldn't electrons crashing into the nucleus be a common event? If so, why have I never heard about this?
Today we have abandoned the solar system model of the atom in favor of the Schr&#246;dinger model: electrons are standing waves distributed through the spherical volume of the atom. Nevertheless, we still understand electronic energy levels as being quantized. Electrons are not permitted to fall into the nucleus because this would involve a violation of quantization.
Finding the electron in the nucleus would also be a violation of the Uncertainty Relation: we would know the electron's position and momentum simultaneously! In fact, the electron's velocity can be approximated by solving the expression for the uncertainty in velocity, using the electron's rest mass and the mean distance of the electron from the nucleus (which can be calculated from the expression for the atomic orbital -- a wave equation! -- in which the electron is located).
Electrons are inherently fuzzy particles, especially when they are in atoms -- and the "fuzz" is on the order of the size of the atom. This means that, while the electron has a certain probability of being "in" the nucleus, the probability can never be 100%.
It is not a common event, but something like that does happen: electron capture (http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/radact2.html#c3).
Not really. It would be allowed in the nucleus but for the Uncertainty Principle. However, because of Heisenberg, it isn't.
Actually, the way it's worded there, you could have an electron in the nucleus. All you need

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Retrieved Text: According to the Rutherford-Bohr model, electrons were thought to occupy fixed, circular orbits around the nucleus of an atom. The electrons with the lowest energy levels occupied the lowest orbits. Electrons with higher energy levels would occupy higher orbits. Whereas the planetary orbits in our solar system all lie on (or very close to) a two-dimensional orbital plane, electron orbits were believed to occupy a number of different orbital planes, spawning the concept of three-dimensional electron shells.
We know now that the Rutherford-Bohr model does not accurately represent the way in which electrons behave. They certainly do not occupy neat circular orbits - the reality is far more complex. Nevertheless, the Rutherford-Bohr model is still taught in schools and colleges because it gives us a good conceptual framework for thinking about electrons and their energy levels. For that reason, we will start by by exploring the concept of electron shells, and then go on to examine the concept of orbitals.
Before we do anything else, let's try and get a little perspective. At the time of writing, the periodic table contains one hundred and eighteen (118) elements. The first element in the table is hydrogen (H), which has the atomic number one (1) because it has one proton and one electron. The last element in the table is oganesson (Og), which has the atomic number one hundred and eighteen (118) because it has one hundred and eighteen protons and one hundred and eighteen electrons.
When dealing with the complexity of an atom's electron configuration, therefore, the worst-case scenario is

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Retrieved Text: Bohr's idea that electrons are found in different orbitals or energy levels was an important step in understanding the structure of an atom. Louis de Broglie's particle-wave relationship was also a crucial development.
Werner Heisenberg and Erwin Schrodinger were able to take these ideas and develop modern quantum mechanics. The main significance of quantum mechanics is the ability to very accurately predict physical properties using basic mathematical principles. Heisenberg and Schrodinger used different kinds of mathematics to explain atomic structure, but they ultimately reached similar results.
The key approach by Schrodinger was to recognize the factors influencing the energy of an electron in an atom. He saw that there would be contributions from Coulomb's law, because of attractive forces between the electron and the nucleus as well as repulsive factors between different electrons. In addition, Schrodinger recognized that there would be a kinetic energy component related to the wavelength of the electron. Schrodinger combined these factors into "the Schrodinger wave equation."
Figure AT3.1. The factors Schrodinger accounted for in his wave equation. Each factor influences the energy of an electron.
Solving the wave equation is very useful. A solution to the equation, which is called a wave function, can indicate the energy of an electron in an atom. The solution can also be combined with other mathematical relations that will give specific predictions of different properties of atoms and molecules.
The Schrodinger wave equation is an approach to describing an electron.
The solution to the wave equation is called a wavefunction.
What happens to the energy of an electron as its wavelength gets

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Retrieved Text: And in my mind, something like this provides a much better understanding of how things work - much better than: "an equation [or a principle] says so" ..
I vote de Broglie. He seems to have been sidelined and never made any further significant contributions to physics. It would be a testament to his foresight and give him more significance in the history of physics. I have for years thought quantum mechanics lacking clarity. No wonder quantum gravity has eluded physics for 100 years.
From the previously mentioned article.
"The experiments began a decade ago, when Yves Couder and colleagues at Paris Diderot University discovered that vibrating a silicon oil bath up and down at a particular frequency can induce a droplet to bounce along the surface. The droplet’s path, they found, was guided by the slanted contours of the liquid’s surface generated from the droplet’s own bounces — a mutual particle-wave interaction analogous to de Broglie’s pilot-wave concept."
In a modified form this describes gravity.
You can't really use an electron to release energy from a nucleus.
- For one thing, the electron very rarely interacts with the nucleus of an atom.
- And in those rare instances where an interaction does occur, much of the energy is carried away by the ghostly neutrino, which we can't capture as an energy source.
Combining two deuterium nuclei (or a dueterium & a tritium) to make a Helium nucleus does release a usable amount of energy.
- However, the wavelength of an electron is too long to draw the two nuclei together close enough for a

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Retrieved Text: As quantum mechanics theory posits, since electrons are negatively charged they are attracted to nuclear protons by a force called "binding energy." Each "n" orbit possesses its own binding energy value expressed in "electron volts." The closer the electron is to a hydrogen atom's proton nucleus, the greater the binding energy. As an electron jumps from an orbit with a lower binding energy to an orbit with greater energy (n2 to n1 for example), it emits light at a specific ultraviolet frequency. Light from the n2 to n1 jump corresponds to 121.6 nanometers and is called "Lyman-alpha" radiation, named for Theodore Lyman, who first discovered it in 1906.

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Retrieved Text: Electron scattering from nuclei, provides us with an invaluable tool to probe the wide variety of nuclear and nucleonic properties, because it has proven itself as one of the most effective methods of studying the properties of the energy levels of atomic nuclei, so it has provided a wealth of information, mapping out nuclear ground state charge densities and precise transition charge and current densities for the excitation of single particle states and for collective states. In the electron scattering, the target is probed through the well understood electromagnetic interaction. Since the interaction is relatively weak, the measurement can be made on the target nucleus without greatly disturbing its structure. With electron scattering the cross section can be related to the transition matrix elements of the local charge and current density operators, and thus directly to the structure of the target nucleus itself. Electron scattering allows the variation of three-momentum transferred q to the target while the excitation energy is kept fixed.

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Retrieved Text: It is necessary to know the most favourable arrangement for any given number of electron pairs surrounding any particular atom. These arrangements are found using simple geometrical constructions. This involves placing the nucleus of the atom in question at the centre of a sphere and then placing the electron pairs on the surface of the sphere so that they are as far apart as possible. The resulting arrangements are often intuitively obvious.
For the case of just two electron pairs, the arrangement is simple and the minimum energy configuration is when the electron pairs form a linear arrangement with the nucleus. In this configuration the electron pair-nucleus-electron pair angle is 180°. The coordination geometry of the central atom is described as linear.
Arrangement for 2 electron pairs on the surface of a sphere.
Three electron pairs arrange themselves trigonally, that is with bond angles of 120°. For four electron pairs, one might expect the square-planar geometry to be favourable. However, tetrahedral bond angles are 109.5°, larger than the square-planar angles of 90°. If, for the purposes of illustration, the electron pairs are assumed to be points then it should be clear that, for similar bond lengths, the electron pairs are necessarily further apart in the tetrahedral arrangement than in a square planar arrangement. There is more electron pair-electron pair repulsion in the square-planar geometry and so the tetrahedral geometry is favoured.
Arrangements for 3 and 4 electron pairs on the surface of a sphere.
The case of five coordination is a little trickier. Most molecules whose shape is determined by five

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Retrieved Text: In general, the size of atoms increases as a group is descended. For example, cesium is larger than lithium. As a period is transversed from left to right, the size of the atom decreases. For example, a fluorine atom is smaller than a lithium atom.
An oxygen atom gains an electron, thereby providing more electron density to shield the electrons from the positively charged nucleus. Consequently, the electron cloud expands. The anion is larger than the atom from which it was derived.
An oxygen atom with its ground state electron configuration is shown losing an electron. The cation that results from this ionization has less electron density to shield the remaining electrons from the nucleus. Therefore, the remaining electrons are more strongly attracted to the positively charged nucleus and the atom shrinks in size.

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Retrieved Text: Electrons revolves around the nucleus in certain orbits. Each orbit is having certain energy level. These orbits are called stationary orbits. The orbit near to nucleus is having low energy level and the outer orbit is having higher energy level.
An electron can revolves in certain energy level without losing any energy. On addition of energy to the atom, the electron jumps to orbit of higher energy level.
‘λ’ is the wave length of light emitted (in meter).
The centripetal force due to electrostatic attraction between positively charged nucleus and negatively charges electron is equal to the centrifugal force of electron moving in circular orbits.
Where, n is an integer called quantum number.
The radius of the orbit is proportional to n2 and the velocity of electron is inversely proportional to n. These assumptions led to results which have been found correct of being tested.
It is applied to one electron atom i.e. hydrogen atom. It cannot be easily extended to explain the more complicated atoms.
It does not give any rule or restriction regarding the transition of an electron from one orbit to another orbit.
It introduced only one quantum number n. Whereas, experimental evidence concerning fine structure of spectral line suggests the more additional quantum numbers.
The quantitative explanation of chemical bonding cannot be explained by the Bohr’s atomic model.

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Retrieved Text: Electron Gain Enthalpy(EGE) is the energy released when electron is added to an isolated gaseous atom.
Atom Size – In smaller atoms, incoming electrons are placed closed to the nucleus. So addition becomes easy.
Nuclear Charge – Higher nuclear charge attracts the incoming electrons making it easy.
Type of sub-shell – The order of the electron gain enthalpy for the sub-shells is s > p > d > f. Higher the sub-shell, higher the number of electrons it can accommodate. Lower sub-shells are packed tightly whereas the higher sub-shells are packed loosely because of the high number of electrons it accommodates. Electrons added to higher sub-shells face lesser repulsion from the existing electrons in that sub-shell.
Electronic configuration – Fully-filled and Half-filled electrons in outermost shell have extra stability. Atoms which require electron to achieve fully-filled and half-filled status accommodates the incoming electrons with less energy.
Electron Gain Enthalpy is opposite of Ionisation enthalpy.
When an electron is added to an atom, energy is released.
The added electrons faces repulsion from the existing electrons but it gets support because of nuclear attraction.
When energy is required to add an electron, it is called as positive electron gain enthalpy.
When energy is released during addition of electron, it is called negative electron gain enthalpy.
Variation of electron gain enthalpy in period: When we we move across the period, the atomic radius(click this link to know why it decreases) decreases making it easy to add electrons because of higher nuclear force attraction.
Variation of electron gain enthalpy in group: When we we move down the periodic group, the atomic

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Retrieved Text: I recently learned about orbitals in class, and I am really confused.
I am very confused about what the orbitals look like, what the signs (such as $-2s, ---2p$ etc.) mean and how they work.
What they taught us was how there are little spaces that the electrons can fit through, because they want to get to the center of the atom, and how $2s$ is in the shape of the sphere.
But I am confused how everything is laid out. Is the "sphere" shape inside the shell and around the nucleus, or is it containing the shell. but inside another shell.
They also introduced something about the $x,y,z$ axis and I am just as confused on that too.
First thing you need to understand is that orbitals are not actual physical things that exist. Simply put, an orbital is a function that describes the probability of finding the electron with certain energy at certain distance from the nucleus. The shapes of the orbitals are just the boundaries of space where you can find the electron 90% of the time.
Electrons behave both as particles and waves. Their wave behavior is described by what is called a wave function. It has two components - radial and angular. The radial component depends on the distance from the nucleus while the angular depends on the direction. It is the angular component that shapes the orbitals. Just as it is, the wave function does not have any physical meaning, but it's square is proportional to the probability of finding the electron in a particular region

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Retrieved Text: As an electron approaches a nucleus from infinity, it becomes 'bound' - it is attached to the nucleus, if you like. In this bound state, the electron occupies what is called an energy level. A nucleus has a discrete number of energy levels, and so electrons bound to a certain nucleus can only take on certain potential energies. These energies are negative by convention.
The lowest (most negative) energy level is denoted n=1, the next lowest n=2, and so on. The values of these can be found using formulae which you don't need to know about. Alternatively, they may be determined experimentally.
Energy levels in a hydrogen atom. The transition shown from the n=3 level to the n=2 level gives rise to visible light of wavelength 656 nm (red).
where E is energy, h is Planck's constant (6.63 x 10−34 J s), f is frequency, c is the speed of light, and λ is wavelength.
The energy levels of different nuclei are different. Evidence for these energy levels comes from the emission and absorption spectra of atoms. An emission spectrum can be obtained by heating a sample of an element. This gives the electrons energy, so they jump up the energy levels. At random, they then jump down again, giving off photons with measurable frequencies. The formulae above can be used to calculate the difference in energy between the levels between which the electrons have jumped.
An absorption spectrum can be found by passing light through (for example) a gas, and observing the frequencies of light which are absorbed. These frequencies

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Retrieved Text: Could this be a plausible way to find out how an electron moves around the nucleus in a hydrogen atom?
Are there fields corresponding to the composite particles (e.g. hydrogen atom field)?
How can we prove that 1 electron was in 2 places at one time. Theoretically, how could we ever prove this? How would we distinguish between one electron being destoryed and 2 "partial" electrons being created with different properties than the first?
We know that particles only exhibit wave-like characteristics only when in motion, and also that the electron can be accurately described as a Standing wave, therefore the electron must be in motion around the nucleus.
Since at any one time the electron has a 95% probability to be anywhere in a certain orbital, the electron must be moving at a very high velocity $v$.
A hydrogen atom is suspended at at distance of more than 1 meter from a heavy nucleus which has a sufficient atomic mass such that under its influence pair production can occur.
very implausible, since it is based on assumptions that are gross simplifications of the real situation. You cannot simply postulate whatever you like!

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Retrieved Text: How many times have you used an electronic device and the batteries died? Wouldn’t it be great if batteries could last for 10 or 15 years of normal use? Betavoltaics might be an answer to solving this problem of limited battery life. Get ready to get charged up about this “potential” game-changing technology.
Voltage is the energy carried by a charge. It can be measured as the difference in charge between two points of a circuit. Current, on the other hand, is a measurement of how much electricity passes a certain point on the circuit.
What is the difference between electrical power and electrical energy?
Electrical power is the rate of energy being provided at a specific instance, whereas electrical energy is the amount of power provided over time. Therefore two identical light bulbs would have the capacity to use energy at the same rate and therefore have the same "power" but one may only be on for ten seconds and another for ten hours, so the amount of "energy" used is different.
How do batteries provide electrical energy?
Batteries produce electricity from a chemical reaction. Inside the battery are a cathode and anode. The cathode is connected to the positive terminal, and the anode is connected to the negative terminal. A separator inside the battery keeps the cathode and anode from touching. When the battery is connected to a circuit, a chemical reaction takes place in both the cathode and the anode. The reaction in the anode releases electrons, and the reaction in the cathode accepts these electrons. To get

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Retrieved Text: Periodic table[ edit ] Electron configuration table The form of the periodic table is closely related to the electron configuration of the atoms of the elements. Phosphorus, for instance, is in the third period.
Pauli-Exclusion Principle Wolfgang Pauli postulated that each electron can be described with a unique set of four quantum numbers. The electron configuration can be visualized as the core electronsequivalent to the noble gas of the preceding periodand the valence electrons: It is possible to predict most of the exceptions by Hartree—Fock calculations,  which are an approximate method for taking account of the effect of the other electrons on orbital energies.
Nitrogen, for example, has 3 electrons occupying the 2p orbital.
In bulk materials, this idea helps explain the peculiar properties of lasers and semiconductors. That is, we follow the three important rules: For atoms, the notation consists of a sequence of atomic subshell labels e.
It may be stated as: However, the energy of an electron "in" an atomic orbital depends on the energies of all the other electrons of the atom or ion, or molecule, etc. Hund's Rule Hund's Rule states that when electrons occupy degenerate orbitals i.
The electronic configuration for Cl- can, therefore, be designated as 1s22s22p63s23p6. The fact that the Aufbau principle is based on an approximation can be seen from the fact that there Atom and electron configuration an almost-fixed filling order at all, that, within a given shell, the s-orbital is always filled before the p-orbitals.
If that were the case, the 3d-orbital would have the same energy as the 3p-orbital,

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Retrieved Text: antiparticle: Particle having the same mass, spin, isospin as a particle, but having all additive quantum numbers opposite to those of its respective particle. Antiparticles have the opposite charge of its corresponding particle. Antibaryons are antiparticles to baryons, antileptons are antiparticles to leptons, and antiquarks are antiparticles to quarks. The antiparticle for a particular particle, for example a neutrino, is denoted an antineutrino.
atomic mass unit (amu or u): Unit of mass defined by the convention that the atom 12C has a mass of exactly 12 u; the mass of 1 u is 1.67 ¥ 10-27 kg.
becquerel (Bq): Unit of activity in the International System�one disintegration per second; 1 Bq = 27 pCi.
beta particle (beta radiation, beta ray): An electron of either positive charge (e+ or b+) or negative charge (e, e-or b -) emitted by an atomic nucleus or neutron in the process of a transformation. Beta particles are more penetrating than alpha particles but less than gamma rays or x-rays. Electron capture is a form of beta decay.
boson: A particle having spin that is an integer multiple of h .
conservation law: A relation asserting that a specific quantity is conserved. For example, conservation of energy, conservation of momentum, conservation of electron number. Conservation laws are connected to symmetries through Noether's theorem.
curie (Ci): The original unit used to describe the intensity of radioactivity in a sample of material. One curie equals thirty-seven billion disintegrations per second, or approximately the radioactivity of one gram of radium. This unit is no longer recognized as part of the International

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Retrieved Text: Classically, I think it is correct to say that Maxwell implies an accelerated electron will "radiate"
What is the quantum take on this please? In particular, what determines the wavelength of the emitted photon?
PS I may ahve asked something like this before, but I never found an answer. This is a re-phrasing of the question.
PPS I know one should not try to interpret what the maths says in practical terms! cf, maths of a car's front suspension is same as how you tune a radio, but my radio is not made of springs and shock absorbers!
It is the same quantum mechanically. That is why the electron in an atom cannot be said to orbit the nucleus, as otherwise it would be accelerating and thus emit radiation and lose energy. Instead, quantum mechanics showed that the electron is in a stationary state around the nucleus.
"Accelerated electron photon emission" You must log in or register to reply here.
Electron energy states and photon emission?

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Retrieved Text: It might be some way off but computers users in the future could take data off a disk drive and move it into the nucleus of an atom.
Scientists have demonstrated what is being called the "ultimate miniaturisation of computer memory," storing data for nearly 2 seconds in the nucleus of an atom. This is a key step in the development of quantum computers, according to the National Science Foundation (NSF).
Using a new technique, an international team of scientists "demonstrated that information stored in the nucleus has a lifetime of about 1 ¾ seconds," said the NSF, describing a new study in the journal Nature. "This is significant because before this technique was developed, the longest researchers could preserve quantum information in silicon was less than one-tenth of a second. Other researchers studying quantum computing recently calculated that if a quantum system could store information for at least 1 second, error correction techniques could then protect that data for an indefinite period of time."
The scientists, from Princeton University, Oxford University and the US Department of Energy, broke the 1-second barrier with a system that uses the electron and nucleus of a phosphorous atom embedded in a silicon crystal. The electron and nucleus each behaved like tiny "quantum magnets" that could store quantum information, but the instability of the electron made it unsuitable for storing information. "To overcome the problem, researchers moved the information into the nucleus where it survived much longer," the NSF states. Data in the electron cloud, which is a million times bigger than the

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Retrieved Text: boson (which then decays to electron and antineutrino) is not shown.
In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which a beta ray, and a respective neutrino are emitted from an atomic nucleus. By beta decay emission, a neutron is transformed into a proton by the emission of an electron, or conversely a proton is converted into a neutron by emission of a positron (positron emission), thus changing the nuclide type. The beta particle and its associated neutrino do not exist within the nucleus prior to beta decay, but are created in the process. By the process of beta decay, an unstable atom obtains a more stable ratio of protons to neutrons. The stability of a nuclide to beta and other forms of decay is determined by its binding energy as a function of its numbers of protons and neutrons. The binding energies of all existing nuclides forms what is called the nuclear valley of stability.
Beta decay is a consequence of the weak force, which is characterized by relatively lengthy decay times. Nucleons are composed of up or down quarks, and the weak force allows a quark to change type by the exchange of a W boson and the creation of an electron/antineutrino or positron/neutrino pair. For example: a neutron, composed of two down quarks and an up quark, decays to a proton composed of a down quark and two up quarks. Decay times for many nuclides that are subject to beta decay can be thousands of years.
The two types of beta

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Retrieved Text: As seen in the previous section on the octet rule, atoms tend to lose or gain electrons in order to attain a full valence shell and the stability a full valence shell imparts. Because electrons are negatively charged, an atom becomes positively or negatively charged as it loses or gains an electron, respectively. Any atom or group of atoms with a net charge (whether positive or negative) is called an ion. A positively charged ion is a cation while a negatively charged ion is an anion. In this section, we briefly look at some of the processes through which electrons are gained and lost in the formation of ions.
The process of gaining or losing an electron requires energy. There are two common ways to measure this energy change: ionization energy and electron affinity.
The ionization energy is the energy it takes to fully remove an electron from the atom. Ionization energy is a property that varies predictably across the periodic table. Group I and II elements with few electrons in their outer shell have very low ionization energies, while ionization energies increase dramatically moving right along the periodic table. The octet rule gives a straightforward (albeit simplified) explanation of this trend: elements with few valence electrons (those on the left of the periodic table) readily give them up in order to attain a full octet within their inner shells.
When several electrons are removed from an atom, the energy that it takes to remove the first electron is called the first ionization energy, the energy it takes to

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Retrieved Text: 1. Be able to state how certain properties of atoms vary based on their relative position on the periodic table.
One of the reasons the periodic table is so useful is because its structure allows us to qualitatively determine how some properties of the elements vary versus their position on the periodic table. The variation of properties versus position on the periodic table is called periodic trends. There is no other tool in science that allows us to judge relative properties of a class of objects like this, which makes the periodic table a very useful tool. Many periodic trends are general. There may be a few points where an opposite trend is seen, but there is an overall trend when considered across a whole row or down a whole column of the periodic table.
Many of the periodic properties of atoms depend on electron configuration; in particular, the valence electrons and their level of attraction to the nucleus.
Where Z is the nuclear charge (equal to the number of protons), and S is the screening constant which can be approximated to the number of non-valence, “core” electrons.
Approximate the effective nuclear charge of magnesium.
First we must determine the electron configuration of magnesium to determine the number of core electrons.
Mg =1s2 2s2 2p6 3s2 = [Ne]3s2, therefore magnesium has 10 core electrons from its 1s2, 2s2, 2p6 orbitals.
Magnesium is element 12, so it has 12 protons and a nuclear charge of 12.
Moving left to right across a period on the periodic table, each subsequent element has an additional proton and

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Retrieved Text: The electronic structure of an atom plays the major role in its chemistry.
Elements consist of only one kind of atom and cannot be decomposed into simpler substances. Our planet is made up of some 90 elements. (Tiny amounts — sometimes only a few atoms — of additional elements have been made in nuclear physics laboratories, but they play no role in our story). Of these 90, only 25 or so are used to build living things. The table shows the 11 most prevalent elements in the lithosphere (the earth's crust) and in the human body.
For example, hydrogen, carbon, and nitrogen together represent less than 1% of the atoms found in the earth's crust but some 74% of the atoms in living matter.
one of the properties of life is to take up certain elements that are scarce in the nonliving world and concentrate them within living cells.
Some sea animals accumulate elements like vanadium and iodine within their cells to concentrations a thousand or more times as great as in the surrounding sea water. It has even been proposed that uranium be "mined" from the sea by extracting it from certain algae that can take up uranium from sea water and concentrate it within their cells.
There is still some uncertainty about the exact number of elements required by living things. Some elements, e.g., aluminum, are found in tiny amounts in living tissue, but whether they are playing an essential role or are simply an accidental acquisition (aluminum probably is) is sometimes difficult to determine.
Each element is made up

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Input Text: Read the passage below and choose the right answer to the following question (choices are increase or decrease ):

As blood glucose levels decrease, less insulin is produced.


Polly was managing her diabetes. As her blood glucose levels increase or decrease, her body produces more insulin so she would need to account for this?

Target Text: increase

#### Retrieved Documents ####

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Retrieved Text: Turns out, when BGs drop, the body produces a chemical that dogs can detect through smell. This discovery is predicted to change the way those living with Diabetes diagnose and treat low BGs. Cool discovery and good news for the diabetes community.
This is a fun perspective on the highs and lows of the T1 life by a young woman who lives it every day. Given that Nick Jonas is also an advocate for T1, I think he’d approve.
Coaching an athlete with T1D? This post’s for you!
Cole pitching for the first time during fall ball.
Cole was a pretty active kid before his diagnosis, but now that we know exercise makes insulin “work” better, we keep him active all year long–spring and fall baseball, basketball, swim team, and archery. Less than a week after his diagnosis in Summer 2013, he was back in the pool, competing in a swim meet (yes, I was a nervous wreck!). We were fortunate because his swim coach was familiar with the disease and did all she could to ensure Cole was safe. But not all the coaches we had were that caring. Most have fallen somewhere between mildly accommodating and indifferent. Thankfully, no one has been outright unsupportive (though I do think his baseball coach this spring was less than thrilled when I told him Cole could not slide into base because he’d rip his CGM out). I don’t think these are bad coaches…they just don’t know anything about Type 1 Diabetes, and many likely confuse the disease with its more vilified

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Retrieved Text: For Angela Valdez, being diagnosed with diabetes was an awakening. The disorder ran in her family, but she didn't think it would happen to her. And when it did, she acted by modifying her diet and physical activity. She was doing everything right — almost.
Unfortunately, like Valdez, many patients with diabetes do not track their blood glucose regularly. According to Edward Chao, DO, associate clinical professor of medicine at University of California San Diego School of Medicine and a physician at Veterans Affairs San Diego Healthcare System, one-quarter of persons receiving insulin treatment infrequently or never test their blood glucose. Another 65 percent of patients who use other drugs to treat their diabetes test just once a month or less.
Edward Chao,DO, is the principal investigator of a phase I clinical trial testing the accuracy of a needleless glucose monitor developed by University of California San Diego Jacobs School of Engineering researchers that adheres to the skin like a temporary tattoo to read blood sugar levels.
"Adherence to chronic disease management is low — about 50 percent. Diabetes is no exception," said Chao. "There's more self-management involved in diabetes, including using needles to test blood glucose, monitoring foot health, managing medications and keeping regular clinical appointments. That's a lot more than many other conditions. We need to introduce a tool that reduces discomfort or inconvenience to increase vital monitoring of glucose."
Enter a needleless glucose monitor dubbed the tattoo sensor, which measures glucose levels through sweat on the skin. Developed by UC San Diego Jacobs School of Engineering researchers

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Retrieved Text: Sandra is a writer who is passionate about education and has visited 37 colleges and universitys on five continents. She has also studied six languages, which she loves to practice on her international trips. In addition to travel and languages, Sandra loves dogs, cooking, and hiking.
from our pancreas gland does not produce enough insulin or produces the hormone insulin, the hormone can not be used effectively in the evolving situation and life-long disease. As a result, people ate foods that blood glucose can not use the glucose and blood sugar rises (hyperglycemia).
Most of the food we eat, especially foods that contain carbohydrates in the body is converted into glucose to be used for energy. The stomach is an organ located in the posterior surface of the pancreas, muscles and other tissues of our glucose from the blood to use as energy that allows taking â€œinsulinâ€� produces a hormone called. Of bleeding in from the glucose, insulin, the hormone enters the cell through. The cells use glucose as fuel. If you need to fuel your body is more than the amount of glucose in the liver (glycogen candy store), is stored in fat tissue, simple Arthro 7.
Nondiabetic individual fasting blood glucose levels 120 mg / dL, as toughness (two hours after the meal starts) 140 mg / dL the impasse. Fasting or postprandial blood glucose level measured to be greater than this value indicates the presence of diabetes.
Whether a person with diabetes Fasting Blood Glucose (FBG) measurement or Oral Glucose Tolerance Test (OGTT) performed is determined. FBG

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Retrieved Text: My nine-year-old daughter was diagnosed with type 1 about a year ago and went on a Medtronic MiniMed Veo pump in July. Three weeks ago, she became really lethargic quite quickly and her blood sugar was elevated constantly, day and night. We ended up in the Emergency Room where they did laboratory blood work but nothing came back so we were told it was viral. After a week off, she went back to school but her blood sugar was hardly ever below 14 mmol/L [252 mg/dl] even after raising her basal rates and a temporary basal rate running between 140 to 180%.
Last week, she developed a cold and became even more lethargic and her blood sugar was again elevated so I increased all basal rates again. Friday, the symptoms of the cold disappeared but the lethargy has her off school again, barely moving and feeling quite low. After speaking with her SDN, I have raised her basal rates again but she is still requiring a temporary basal, too, of about 140%. Should I be concerned? This is all still new and not how she has reacted before when she has caught bugs. What should I do?
When you are new to caring for diabetes mellitus (and sometimes when you are not so new), I think that somehow we, as clinician educators, do not make it clearer from the beginning that management recommendations are to HELP MANAGE glucose levels. Families, understandably, want consistency and glucose levels may not be...even when they are. By this, I mean that too

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Retrieved Text: Fifth grader Sophia Daugherty died just last Wednesday from complications brought about by her Type 1 diabetes. The death came just days after her blood sugar dropped dramatically low during a sleepover at a friend’s house.
Sophia Daugherty was at a friend’s house during a sleepover when she was found unresponsive on Sunday. Evidently, her blood sugar had dropped dramatically low and she was sent to the hospital with her brain already swelling. After days in the hospital, Sophia succumbed to the illness and died just last Wednesday. Sophia’s organs were donated to other children in need.
Despite her Type 1 diabetes, Sophia was described as a popular girl who was sweet and active, as she was a Girl Scout, a cheerleader, and a softball player. Everyone knew her because there were only 80 children in her grade, and as a result classmates, teachers, and even school administrators are mourning her loss.
A GoFundMe page is set up for Sophia’s family.
People without diabetes can properly produce insulin so there is enough glucose to maintain blood sugar levels, but those with diabetes cannot, so they need to take insulin so as to help the body to use glucose for energy, otherwise the body might not perform its proper functions.
Low blood sugar or hypoglycemia is a potentially dangerous condition that happens to people with diabetes, often when they skip meals, take too much medication, eat less than normal, or exercise more than the usual. Blood sugar levels are considered low when it drops to below 70 mg/dL, and those levels can

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Retrieved Text: Dealing with gestational diabetes, a glucose intolerance diagnosed during pregnancy, requires a careful balancing act.
Gestational diabetes is glucose intolerance diagnosed while a woman is pregnant, usually late in the second trimester or in the third. The disease, like other forms of diabetes, affects how the body handles sugar, and the result in this case is that too much sugar remains in the bloodstream. Gestational diabetes raises the risk of complications during delivery.
In normal digestion, the sugar molecule glucose-an important source of energy-is absorbed into cells with the help of insulin, produced by the pancreas gland. During pregnancy, the placenta secretes a hormone called human placental lactogen to protect the foetus and make sure it receives enough energy even if the mother fails to.
Gestational diabetes raises the risk of complications during delivery.
The hormones make it harder for the mother's cells to absorb glucose because they raise her resistance to insulin. Thus, too much sugar may stay in her blood. Her insulin resistance may increase during pregnancy as the placenta grows and produces more of the offending hormones.
Rhonda Bentley-Lewis, MD, an endocrinologist at Harvard Medical School and Brigham and Women's Hospital, says that about 4% of pregnant women are diagnosed with gestational diabetes. Its prevalence can range from 1 to 14%, depending on risk factors.
Women at risk include those who are over 25, overweight before pregnancy, have first-degree relatives with type II diabetes (the most common form, in which either the body does not produce enough insulin or the cells ignore the insulin), and who have had gestational

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Rank: 6
Score: 68.80076
Retrieved Text: Rob Varela /Ventura County Star: Jennifer Mueller, center, walks in Marina Park in Ventura with her parents Kristy and Don Schadt and their dogs Nicholas and Patches to check out a possible route for their upcoming doggie-thon fundraiser on June 29.
Struggling for 18 years with type 1 diabetes, Jennifer Mueller has inspired a benefit to support Heaven Scent Paws, a nonprofit that trains dogs to know when their owners' blood sugar is ready to drop — a life-saving skill that even the most sophisticated monitors cannot detect.
"Many type 1 diabetics have severe complications and difficulty managing their diabetes from the beginning of their diagnosis," said Mueller, 33, of Oak View. "Diabetic service dogs can help us manage our diabetes significantly."
For Mueller and others with type 1 diabetes, managing the disease is a full-time job.
"When my diabetes is uncontrolled, it's a horrible feeling of powerlessness and frustration," she said. "I feel scared that I might die or have an episode in public."
Diagnosed with it at 15, she said she believes that having a service dog will help her manage the disease much better.
"Since I have hypoglycemia unawareness, a service dog can help me significantly with that; the dogs can smell the change in your body well before your blood sugars begin to drop and then alert me," Mueller said.
"I will be able to sleep at night without the fear of not waking up," she said. "This dog will help me regain confidence that I can go about my life as normally as possible again, with the assistance

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Rank: 7
Score: 68.26152
Retrieved Text: What is the pancreas? What is an artificial pancreas device system?
The pancreas is an organ in the body that secretes several hormones, including insulin and glucagon, as well as digestive enzymes that help break down food. Insulin helps cells in the body take up glucose (sugar) from the blood to use for energy, which lowers blood glucose levels. Glucagon causes the liver to release stored glucose, which raises blood glucose levels.
Type 1 diabetes occurs when the pancreas produces little or none of the insulin needed to regulate blood glucose. Type 2 diabetes occurs when the pancreas does not produce enough insulin or the body becomes resistant to the insulin that is present. Patients with type 1 diabetes and some patients with type 2 diabetes inject insulin, and occasionally glucagon, to regulate their blood glucose, which is critical to lower their risk of long-term complications such as blindness, kidney failure and cardiovascular disease.
When managing diabetes, many patients must vigilantly test blood glucose with a glucose meter, calculate insulin doses, and administer necessary insulin doses with a needle or insulin infusion pump to lower blood glucose. Glucagon may be injected in an emergency to treat severe low blood glucose. Some patients benefit from additional monitoring with a continuous glucose monitoring system.
The FDA is collaborating with diabetes patient groups, diabetes care providers, medical device manufactures, researchers, and academic investigators to foster innovation by clarifying agency expectations for clinical studies and product approvals. These efforts have accelerated the development of the first hybrid closed loop system, the Medtronic's MiniMed 670G

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Rank: 8
Score: 68.212204
Retrieved Text: A leading endocrinologist shares new advances in managing this chronic — and common — feline disease. Hint: Weight control is your best weapon.
Diabetes mellitus is on the rise among cats in the United States, according to a survey of clinics nationwide — an increase that has been correlated with a rise in obesity. Although it’s hard to draw definitive conclusions from the results of the survey, there’s no question that feline weight control is a key to preventing this chronic disease.
Most cats with diabetes will require twice daily insulin injections.
There are two main categories of diabetes in humans. Type 1 is, in essence, an autoimmune disease that causes the body to attack and destroy insulin-producing beta cells in the pancreas. It’s manageable with injections of insulin, but it’s not reversible.
In the much more common type 2, typically seen in overweight adults and, increasingly, among obese children, the pancreas still produces insulin, but either it does not produce enough or the body is resistant to the insulin it does produce. If it hasn’t progressed to a dangerous stage, type 2 diabetes can often be controlled by diet and oral medications.
Type 2 is the variety to which cats are usually subject, but by the time most cats are diagnosed, the disease is fairly advanced. This means that they are likely to be insulin dependent for the rest of their lives, according to Dr. Mahony, who is board certified by both the American and European Colleges of Veterinary Internal Medicine.
Many of the same factors that come into play in

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Rank: 9
Score: 68.211555
Retrieved Text: Melandia in her home town of Fairhaven, Mass.
Melandia Coutinho may be the only 10-year-old who can talk about Harry Potter and the American Revolution in the same breath. She takes Portuguese, plays on two soccer leagues, and she still has energy for homework and climbing trees with her younger brother Marcio.
Melandia was referred to endocrinologist Dr. Gregory Goodwin of Boston Children’s Hospital. Within hours of the physical, soccer was cancelled, Marcio was with his grandparents, and Chanda, Jeff and Melandia were packed and on their way to Boston.
Type 1 diabetes is a chronic condition in which the body produces little or no insulin. If managed properly, a child with Type 1 diabetes can maintain a very healthy, active lifestyle, but it takes work and can be overwhelming for families.
Melandia’s blood glucose numbers were steady enough at that point that she stopped needing insulin injections. Instead she began receiving insulin through a pump: a small, computerized device programmed to deliver insulin directly into her body.
Goodwin made small adjustments to Melandia’s insulin intake and additional changes again a week later to lower her blood sugar.
For Melandia’s latest two appointments and any other followups going forward, the drive to see Goodwin is much shorter. With the opening of a new facility at Boston Children’s at North Dartmouth—seven miles from the Coutinho’s home on the south coast—expanded services have become available, including continuing care for return diabetes patients.
With two years of diabetes management under her belt and her blood sugar levels down, 10-year-old Melandia is thriving.
She recently started fifth grade

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Rank: 10
Score: 67.85849
Retrieved Text: My first pregnancy was pretty good, I had no problems. Now I'm having my second pregnancy and am 33 weeks. Last week my doctor checked my blood sugar and it was 210 mg/dl.
She advised to make some changes on my diet, to do more exercise, and gave me insulin shots.
I didn't want to go for insulin, I started my diet changes and exercise, and now my sugar levels are ok as my doctor said.
I want to know why did happen gestational diabetes second pregnancy while everything was ok with the first pregnancy? Has anything I've eaten or done cause me to have diabetes?
One last thing: I've heard about this acclimation or adaption during pregnancy. How far do they affect me and my baby?
Usually, gestational diabetes begins when your body is unable to produce and utilize its need from insulin during pregnancy, this means that glucose can’t be properly used by your body to produce energy; glucose will actually remain high in your blood (hyperglycemia); raising the results of your oral glucose tolerance test.
•	Being obese; you might have gained excess weight after your first pregnancy and failed to regain your normal weight before the second one.
•	Finally, gestational diabetes tends to occur more frequently in African Americans, Latino Hispanic, Native Americans Pacific Islanders individuals.
My sister had got gestational diabetes when she was pregnant, after delivery was cured from her GDM, but her doctor advises her to adopt healthy dietary habits, have regular physical exercise, and avoid excess sugars for the rest of her life to avoid developing type

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Rank: 11
Score: 67.79231
Retrieved Text: You might not think of a Type 1 diabetes diagnosis as a positive thing, but for Jeannie Williams, a consultant at the Jackson location of Medical Weight Loss Clinic, it’s exactly that.
She acknowledges that diabetes has affected her life in various ways, but believes it has helped her life for the better. Since November is National Diabetes Month, we’re exploring why.
“From a young age, I had to learn and understand how foods, illness and just simple everyday life choices impact our bodies,” Jeannie says.
It even helps her in her work, because it helps her closely relate to her patients.
Jeannie, who is now 32, was diagnosed with the autoimmune disease when she was 9 years old.
She manages her diabetes with three to five insulin injections per day, along with following a healthy diet. Fortunately, there have been improvements in managing Type 1 over the two decades she has lived with the disease. Jeannie says she has a much easier time scheduling injections and managing her blood sugar levels thanks to that progress.
Jeannie believes that there are misunderstandings around Type 1 diabetes as well as how it differs from Type 2.
Meanwhile, with Type 2 diabetes, the body doesn’t use the insulin it produces effectively, so the pancreas tries to compensate by producing more. However, the body is essentially insulin resistant. Type 2 can be controlled and even reversed through a healthy diet and exercise, medications and sometimes insulin injections.
In addition, Type 1 cannot be prevented, but there are several factors that make someone at risk for Type 2

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Rank: 12
Score: 67.46601
Retrieved Text: Type 1 Diabetes and how it happens? Let’s dig deeper. What does diabetes mean anyway? Well, it just means that the blood sugar is too high. This blood sugar is also called glucose.
And how can we get rid of glucose? Where does it come from? Well, it comes from the food we eat and no, we should not get rid of it altogether for we need it for energy. We just need to have the right amount in the right place.
What is one to do? With Type 1 or Type I Diabetes, it looks like we are between a rock and a hard place. Don’t worry, we will show you what to do later. Meantime watch how this courageous boy deals with his type 1 diabetes.
Type 1 Diabetes used to be known as juvenile diabetes or insulin-dependent diabetes because it seemed to occur in children and adolescent. This is also usually seen in young adults when the cells that produce insulin in the pancreas are destroyed.
How are these cells destroyed in Type 1 or Type I Diabetes, you asked? Well, the body immune system attacked and destroyed these cells. As a result, these cells cannot get the glucose they need.
There is something new you ought to know about this so-called juvenile-onset diabetes or Type 1 Diabetes. Now the authorities are saying it does not only appear in children. Why? Because they have seen it appearing at anytime in life.
After you're done going over the book there, make sure you click the back browser button to come

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Rank: 13
Score: 67.22954
Retrieved Text: Many cat owners will agree that cats can be incredibly fussy little creatures when it comes to their food. Yet if your cat has feline diabetes, what they eat is an important part of treating the disease. A diabetes diet for felines is necessary to keep your cat feeling her best.
Cats are obligate carnivores, which means that need to eat meat in order to survive and thrive. Carbohydrates should form a very small portion of their diet. A cat's body processes protein much more efficiently than carbohydrates. That said, most commerical cat foods do have some carbs in them -- but it should be a very small percentage of the total (some say 5% or less) and should be in the form of complex carbohydrates, which allow for a slower, steadier release of nutrients. This helps to prevent your diabetic cat's blood sugar levels from fluctuating too much after she eats.
Overweight or obese cats are at greater risk for developing feline diabetes. It's important that diabetic cats maintain a healthy body weight. So if your cat is currently overweight, a lower-calorie food should be provided until your cat is at her optimal body weight. Weight loss should always be safe and gradual. Some diabetic cats are underweight and should be fed a higher-calorie diet until they reach a healthy body weight. In either case, once the cat is at the recommended weight, pet owners should strive to keep them there.
An important consideration when choosing a food is simply whether or not the cat will eat it.

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Rank: 14
Score: 67.17875
Retrieved Text: Here’s a primer on the disease, its effects, the struggle to live with it, and the efforts to treat it.
Lee Alexander uses an insulin pump that communicates with her glucose monitor to track blood sugar levels.
For over four decades, Lee Alexander has struggled with Type 1 diabetes, an autoimmune disease in which the body mistakenly turns on itself, decimating insulin-producing cells in the pancreas.
Unable to make this vital hormone on her own, the Orlando resident depends on synthetic insulin to survive. Without daily doses, her blood sugars, or glucose, can dip too low or spiral too high. Changes in either direction carry imminent threats, some life-threatening, experts say, while sky-high sugars over time can lead to heart or kidney disease, blindness and even limb amputation.
So, 50-year-old Alexander monitors her glucose levels at least five or six times a day, just as she has since age 7, when doctors first diagnosed her. Taught back then to watch for color changes in urine, “I knew which colors to shoot for,” she says with a laugh. A blue paper meant blood sugars were too low; blood-orange colors meant they had jumped too high; but “greens were always good,” keeping pace with her growth and energy needs as a child.
The treatment scenario differs for those diagnosed with Type 2 diabetes, however—a far more prevalent form of the disease, closely linked to obesity and physical inactivity.
In Type 2 diabetes, the pancreas still pumps out insulin, but “there’s too much sugar on board,” Kaplan says, because the pancreas makes too little of

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Rank: 15
Score: 66.0272
Retrieved Text: Prior to my seven year old daughter's diagnosis of type 1 diabetes (about a year and a half ago), she did very well in school, but now the teacher says she just stares off into space when she's supposed to be doing her work, and her grades are dropping. She's very moody, and her sugar has been going up before lunch even if she hasn't eaten much breakfast. Can her diabetes be affecting her schoolwork? She says her eyes get tired. I filed for SSI, and they told me that sometimes the way a child deals with an illness is a disability within itself. Can the way she's dealing with diabetes, affect her schoolwork?
There is growing evidence that changes in blood glucose do affect how children with type�1 diabetes concentrate in school. No doubt low blood glucoses (hypoglycemia) are important, but new studies give new light to how elevated blood glucoses (hyperglycemia) affects school work. You don't indicate what her insulin regimen is but if she is getting higher readings at lunch time, this suggests that she needs more fast-acting insulin in the morning. If she eats a mid-morning snack, then I will presume she is on Regular with breakfast and this may need to be increased. If she does not receive a mid-morning snack, then I presume she is on Humalog or Novolog at breakfast. Discuss your daughter's insulin regimen and meal plan with her diabetes team."Smoothing-out" her glucose readings may do her a lot of good. Also, consider asking her teachers for an IEP

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Rank: 16
Score: 65.97824
Retrieved Text: When your child or teen is diagnosed with diabetes it means that your body does not produce insulin or insulin does not handle well. The diagnosis of type 1 diabetes means your pancreas does not produce insulin. When diagnosed with type 2 diabetes means that your body is not using insulin properly.
Insulin is the hormone secreted by the pancreas whose function is to transport blood glucose into body cells to be used as energy stream.
Without insulin levels blood sugar rise and your body begins to use fat as an energy source.
It is known as ketoacidosis when the patient metabolizes body fat rather than glucose due to insulin deficiency.
The main cause of diabetes ketoacidosis is that it has not been well controlled.
Your child or teen may be taking the wrong dose of insulin or diabetes medication, or have forgotten to take your dose.
If your child is sick, your body is suffering from an infection, has been surgically intervened or has had an accident that causes physical pain, blood glucose rises. If you are young and in the days of her menstrual period, also sugar may go up.
Ketoacidosis can also be, in many cases, the first sign that your child or teen is suffering from diabetes when not yet been detected with medical tests.
When the body breaks down fats it produces chemicals known as ketones. Ketones or acids produced accumulate in the blood and urine.
For the diagnosis of ketoacidosis will be made a quick urine test using a test strip with chemicals that react with ketone bodies in

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Rank: 17
Score: 65.939896
Retrieved Text: Blood glucose regulation is a dynamic process. The art of successful management of diabetic pets is to use exogenous insulin to mimic this dynamic process of blood glucose regulation.
Human labeled insulin has evolved from animal to recombinant to synthetic sourced insulins with variable potency and duration of action. This allows the physician to deliver insulin more precisely and manage diabetes more intensely.
Animal patients may tolerate extremes in blood glucose better than humans and are unable to signal when their blood glucose is low. Veterinarians have the flexibility to manage their patients’ disease tightly with the goal of achieving normal blood glucose or more loosely with the goal of managing clinical signs and reducing the risk of diabetic ketoacidosis.
Veterinarians and their patients are dependent on pet owners’ participation in treatment. Clients’ ability to care for pets can be constrained by budget, time and commitment level. Thus it is imperative to establish a goal for treatment which meets clients’ expectations as well as patients’ medical needs. Realistic treatment goals are to eliminate clinical signs and stabilize body weight while avoiding hypoglycemia.
It is well established that it is possible to induce remission in cats with diabetes with a combination of insulin therapy, diet change and aggressive monitoring. Attempting to induce remission of diabetes in a feline patient is academic at best; if the client does not have the time or resources to monitor blood glucose levels frequently at home. Conversely, the highly motivated cat owner may be left dissatisfied and turn to the internet if she is not offered

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Rank: 18
Score: 65.817604
Retrieved Text: Gestational diabetes, or diabetes that occurs in the second and third trimester of pregnancy and resolves at birth, occurs in approximately 9.2 percent of pregnancies in the United States. Gestational diabetes is defined as impaired glucose tolerance with onset or first recognition during pregnancy. It occurs in women who have never had overt diabetes before but who develop high sugar levels during pregnancy.
While gestational diabetes can be an alarming complication, it can be controlled by maintaining a healthy diet, exercising, and taking medication if needed.
A mother’s blood glucose levels usually return back to normal after delivery. However, she should be closely monitored by her health care provider.
You will probably be tested for gestational diabetes between weeks twenty-four and twenty-eight of your pregnancy, using an oral glucose tolerance test to see how well your body responds to ingesting a large amount of glucose.
If you have a higher risk of gestational diabetes, your doctor may test you earlier, at your first visit during your pregnancy.
For most women, gestational diabetes doesn’t cause any symptoms. However, gestational diabetes screening is part of normal prenatal care.
Your doctor will evaluate your risk factors for gestational diabetes early in your pregnancy. If you have risk factors for gestational diabetes, your doctor will evaluate when screening is right for you.
Routine screening for gestational diabetes involves an oral glucose test. The test involves drinking a sweetened liquid, called Glucola, which contains 50 grams of glucose, also known as 50g OGTT. How the body metabolizes this solution is measured by a blood test.
A blood sugar level

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Rank: 19
Score: 65.524155
Retrieved Text: Consider this: 9.4% of the United States population has some form of diabetes, That's 30.3 million people, making diabetes a common condition among Americans. What isn’t common is the devastating effect it can have on your health if it’s not managed correctly. At her family practice in Perrysburg, Ohio, Dr. Roberta June Guibord has extensive experience helping her patients control the disease, allowing them to lead normal, active lives. To learn more about managing your diabetes, call or book an appointment online.
Diabetes is a catchall term for a group of diseases that interferes with your body’s ability to regulate blood sugar. Sufficiently understanding the condition requires stepping back and examining the importance of proper blood sugar levels.
Blood sugar refers to the amount of glucose your blood contains. Glucose is the primary source of energy for almost every part of your body, from your brain to your muscles.
The glucose in your bloodstream is either derived from the food you eat or produced by your liver, and insulin -- which is secreted by your pancreas -- regulates it.
In all of these instances, the glucose level in your blood isn’t regulated correctly, allowing it to spike and plummet.
The causes of diabetes largely depend on which type of diabetes you have.
With type 1 diabetes, there’s no known cause, but it’s believed that genetics play a role. With type 2 diabetes, lifestyle factors such as obesity play a large role in its development. Lastly, gestational diabetes typically only lasts for the duration of your pregnancy and is caused by increased hormones.
If

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Rank: 20
Score: 65.47877
Retrieved Text: When Lilly Jaffe, 6, gleefully disconnected her insulin pump from her hip last month, her mother, Laurie, forced herself to be brave.
Lilly was cutting the lifeline to the hormone that had kept her alive since she was a month old. That was when she was diagnosed with Type 1 diabetes, meaning she would always need insulin injections.
But thanks to advances in molecular medicine, doctors had reason to believe that Lilly could be weaned off the shots. Because scientists recently had identified the genetic mutation that causes her condition, they knew why her body was not making insulin and they had a way to fix it: a readily available drug.
Now Lilly no longer needs insulin shots to control her blood sugar. Instead, she takes five sulfonylurea pills twice a day.
"Our family is watching a miracle unfold," Jaffe said. "For me, the simple act of removing the battery from her pump and putting it away in a drawer was surreal."
The kind of diabetes Lilly has is rare, so the discovery will help relatively few children. But scientists say it is an example of how genetic discoveries are beginning to allow doctors to treat the root causes of a disease instead of its symptoms.
And for families like Lilly's, the benefit is life-changing.
"We could never let our guard down, having to monitor her closely and constantly," said Jaffe, who lives in the north suburbs. "That meant glucose checks 10 times a day, even at night, and three to five daily insulin injections, not to mention analyzing every bite she ate."
Two

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Rank: 21
Score: 64.75868
Retrieved Text: We’ve talked before about diabetes, but now I want to talk a little more about the different types of diabetes that affect dogs and cats.
Diabetes is a medical condition of both cats and dogs, and it results from a lack of insulin. Insulin is a hormone produced by the pancreas. It has many jobs, but one key job is the transport of glucose into the cells of the body. Without insulin, the cells in the body (be it feline, canine, or human) cannot use glucose, which is key to proper cell function. Glucose is food to our cells.
When there isn’t enough insulin to transport glucose into cells, glucose builds up in the blood. Overtime, the kidneys become overwhelmed and allow glucose to spill over into the urine. This draws water into the urine, causing increased amounts of urine and therefore increased thirst to keep up with urinary water loss.
Though glucose is present in the blood in great numbers, the body cannot detect it and is tricked into thinking that it is starving. In response, the body starts to break down protein and fat for use, as it would during times of actual starvation. This leads to both an increased appetite and weight loss.
Dogs and cats with diabetes will do an awful lot of drinking, urinating, and eating. All the while, they will be losing weight.
There are two types of diabetes, Type I (or insulin dependent) and Type II (or non-insulin dependent).
Type I diabetes is common in dogs and very rare in cats. It results from an

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Rank: 22
Score: 64.684006
Retrieved Text: When Carolyn D’Argenio’s son was two years old, he was diagnosed with type 1 diabetes. Carolyn, herself diagnosed with ADHD, has had to manage the uncommon challenge of tending to her son’s extensive needs alongside her ADHD. Here, Carolyn shares with us her story, some strategies, and information that hopefully will better inform others of the interplay between these two conditions while maybe even saving lives.
Teaching as a college professor for sixteen years, Carolyn has now started to work as an ADHD coach.
Carolyn found out she had ADHD only after one of her students informed her of it.
After looking into ADHD, she decided to take courses at the ADD Coach Academy and later made the transition from being a professor to a full-time coach.
She is also the creator of the list of suggested audio-books for ADHD reWired, found at erictivers.com/audible.
Eric had contacted Carolyn in the past for information regarding a client of his who had type 1 diabetes. Tragically, that client died this past week due to his diabetes. Since then, Eric has been looking more into possible connections between ADHD, diabetes, and other disorders.
We know there are many who don’t understand ADHD, but there are also many who don’t understand the difference between type 1 and type 2 diabetes.
Type 1 diabetes is an autoimmune disease, while type 2 is metabolic in nature.
Type 1 used to be labeled as “juvenile diabetes” before it was found to continue throughout people’s lives.
Some have made analogies between the necessity of managing type 1 diabetes via insulin and managing ADHD

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Rank: 23
Score: 64.52835
Retrieved Text: The world is plagued by disease. Between heart disease, allergies, diabetes, and cancer, we all seem to know someone who’s health causes them anxiety and frustration.
ToMarah Hutton found out first-hand how a change in health can affect quality of life.
ToMarah was living what most of us would consider a typical life. She was a busy mom, focused on her family and responsibilities. She knew that her health wasn’t perfect, but she wasn’t terribly worried about it. That is, until a few strange symptoms sent her to the doctor for a check-up. The diagnosis was one that about 30 million other Americans have heard – type 2 diabetes.
Symptoms of diabetes include sweating, shaking, fast heartbeat, blurred vision, dizziness, and tingling hands or feet, all caused by irregular blood sugar levels. When the body is either unable to produce enough or properly use insulin (a hormone that carries sugar from the blood stream to cells throughout the body) blood sugar levels can dangerously fluctuate.
Researchers also believe there is a genetic link that makes some more susceptible to the disease than others .
ToMarah knew she had put on some weight, but what mom doesn’t? She didn’t always buy organic, but who can afford to? Exercise wasn’t her main hobby, but who has time?
Like so many of us, ToMarah believed she was doing just enough to keep herself healthy. But with her diabetes diagnosis, she realized she had let her health slip away from her and wondered if it was too late to do anything about it.
Cardiovascular disease. Those with

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Rank: 24
Score: 64.475075
Retrieved Text: Diabetes is a chronic disease in which the body either cannot produce insulin or cannot properly use the insulin it produces. Insulin is a hormone that helps glucose enter the body's cells, where it is used for energy. Diabetes therefore causes blood glucose (sugar) levels that are too high.
Type 1 diabetes, sometimes called Juvenile Diabetes, usually develops in childhood, adolescence, or early adulthood. About 10% of those with diabetes have type 1 diabetes. With type 1 diabetes, the body produces very little or no insulin. Type 2 diabetes is the most common form of diabetes (90%), and it usually occurs in adults, but children can be affected as well. With type 2 diabetes, the body does not make enough insulin or is unable to use it properly.
The symptoms below occur when blood glucose levels exceed the normal range. They may or may not be present when a diagnosis of diabetes is made, and they may also occur when a person's diabetes is not well controlled. If you have any of these symptoms, it is important to contact your doctor.
The exact cause of type 1 diabetes is not yet known. However, having a family member (parent, sibling) with type 1 diabetes slightly increases the risk.
Diabetes is diagnosed through a blood glucose test that measures the amount of glucose (sugar) in a sample of blood. Glucose is measured using millimoles per litre (mmol/L). Levels that exceed those outlined in the table below are indicative of diabetes.
The goal of diabetes treatment is to keep blood glucose levels as close

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Rank: 25
Score: 64.45036
Retrieved Text: My six-year-old daughter, who has Down syndrome, was diagnosed with type 1 diabetes when she was four-years-old and has been on Lantus and Apidra ever since. Her blood sugars are always in the 200 to 300 mg/dl [11.1 to 16.7 mmol/L] range, sometimes 300 to 400 mg/dl [16.7 mmol/L to 22.2 mmol/L]. You can count on your fingers the number of times that she has been below 200 mg/dl [11.1 mmol/L]. At present, she is on 10 units of Lantus every morning and 2 to 3 units of Apidra depending on the amount of food that she eats and which I give during breakfast, lunch and dinner. She is a picky eater and we always have a hard time getting her to eat breakfast. Her usual morning blood glucose reading is somewhere from 178 to 285 mg/dl [9.9 to 15.8 mmol/L] and sometimes goes up to 300 mg/dl [16.7 mmol/L]. If I give her 3 units of Apidra within 20 minutes of breakfast and she hasn't eaten enough, she would go as low as 63 mg/dl [3.5 mmol/L], sometimes lower. There are times I would only give her 2 units Apidra because I'm so afraid she'll have hypoglycemia, but, after getting a blood sugar over 200 mg/dl [11.1 mmol/L] two hours after eating, it seems her insulin shot of 2 units is not enough. On the other hand, if I increase it to 3 units, she'll have a low blood sugar. I am deeply worried about the yo-yo blood sugar readings of my beloved daughter. What

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Rank: 26
Score: 64.36565
Retrieved Text: Gina Kolata, a journalist at the New York Times wrote a recent interesting article called ‘Skinny and 119 Pounds but with the health Hallmarks of Obesity‘. She describes Claire Johnson, a patient with a rare case of lipodystrophy, a genetic disorder characterized by the lack of fat.
She was skinny but always ravenously hungry. She could never get fat, because she lacked fat cells.
In college, Claire discovered she had a huge, fatty liver, polycystic ovaries and severely elevated triglycerides – all hallmarks of obesity. Yet she was super skinny.
Dr Simeon Taylor, chief of diabetes at the National Institute of Diabetes, Digestive and Kidney Diseases, finally diagnosed her in 1996 with lipodystrophy. He had several other patients with the same rare genetic syndrome.
These patients had the most severe insulin resistance he had ever seen, but no fat he could see (subcutaneous variety). Patients eventually also developed high blood pressure and type 2 diabetes, diseases typically associated with obesity.
In rodent models of lipodystrophy, researchers transplanted a little fat back into the fat-free mice. The metabolic syndrome disappeared! The fat was protective against insulin resistance, not causative!
We need to understand the new paradigm of insulin resistance to understand how insulin resistance, obesity, fatty liver, and fatty pancreas are actually all different forms of protection our body uses. But what is the underlying disease?
Dr Roger Unger elucidated the basics of the syndrome a few years ago in this article. We’ll take it one step at a time.
As I’ve outlined in my book, The Obesity Code, the basic problem is hyper-insulinemia. There

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Rank: 27
Score: 64.22993
Retrieved Text: Too.uch glucose-lowering medicine, relative to dietary intake, can role in the development of type 1 ddiabetes, but the mechanism is not fully understood. Type 1 diabetes dubbed juvenile onset diabetes is the relatively your appetite and body weight. Cook gets “exhausted”. Some people with type 2 diabetes become dependent additional protection for people with pre-diabetes. Several other signs and symptoms can mark the onset of at any age, but it is most often diagnosed in children, teens, or young adults. Gestational diabetes usually resolves runs in families. Johnson reviews this fascinating topic in the video below, in which he carefully explains how not be used in place of a call or visit to a health professional. Fructose doesn appropriately stimulate insulin, which, as a result, fails to suppress ghrelin (“hunger hormone”) and to stimulate lepton (“satiety hormone”) Rapidly leads to metabolic syndrome, or weight gain and abdominal obesity (beer belly), decreased HDL, increased LLD, elevated triglyceride, elevated blood sugar, and high blood pressure diabetes can have side effects. Carbohydrates are broken down into levels start to rise. Gestational.iabetes is high blood sugar that develops at any with your insulin receptors. 9 Get plenty of omega-3 fats from a high-quality, animal-based source .
She started complaining of tummy ache and visiting the little girls room a lot; she was up at night asking for drinks and this excessive thirst got progressively worse. “On our way to a rehearsal for a show she was in, Ellie became really unwell. We rushed her to Shannondoc where the doctor discovered instantly

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Rank: 28
Score: 64.16055
Retrieved Text: Type 1 diabetes: Insulin-dependent diabetes, juvenile diabetes, or early-onset diabetes—the body produces little or no insulin because the pancreatic cells that make insulin stop working. This results in high blood sugar.
Type 2 diabetes: Insulin resistance is the most common type of diabetes, occurring most often in adulthood and often among people with obesity. Over time, as the body repeatedly secretes insulin in large quantities, the cells become less sensitive and no longer respond to insulin the same way. When this happens, the cells do not get fed and blood sugars rise to dangerous levels.
Gestational diabetes: Affects women during pregnancy and results in progressively rising levels of glucose.
Type 1 diabetes often requires daily injection with insulin since your body does not produce the insulin needed to absorb blood glucose.
Type 2 diabetes means your body produces insulin, but does not react to it correctly so you need an oral medication to help regulate insulin. Together with proper nutrition and exercise, weight loss can also help manage blood glucose levels.
A complete physical along with your full medical history: measure your height, weight, blood pressure, check your mouth, eyes, abdomen, take your pulse, look at your hands and fingers and feet, listen to your heart and lungs, check your skin—especially where you inject insulin, test your reflexes, check dates of how and when you are diagnosed with diabetes, discuss past lab test results, discuss your eating habits, exercise levels, discuss current treatment plan and any incidence of infections or ketoacidosis, or low blood sugar reactions, discuss complication, other medicines you

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Retrieved Text: My 10 year daughter was having symptoms of high blood sugar and, at times, hypoglycemia. I bought a meter and her blood sugars are over 200 mg/dl [11.1 mmol/L] at times. She also has had blood sugars as low as 64 mg/dl [3.6 mmol/L]. Her regular doctor did blood work and her A1c was 5.9 while her cholesterol level was 213. She was referred to an endocrinologist who did a Glucose Tolerance Test (GTT) that was normal, 98 mg/dl [5.4 mmol/L] fasting and 107 mg/dl [5.9 mmol/L] at two hours. Her insulin levels were not done.
At home, her fasting blood sugars are between 100 and 110 mg/dl [5.6 and 6.1 mmol/L]. She was wetting the bed and had two viral UTIs during which her fastings were 130 to 140 mg/dl [7.2 to 7.8 mmol/L]. She is due to be seen by her pediatrician and I was wondering what tests should be done to figure have type 1. Three out of four of her grandparents have type 2 and I had gestational diabetes.
I am not sure that I would do anything. Assuming that the Oral GTT was done properly, then diabetes has been excluded, for the time being. I am disappointed that insulin levels were not measured during the OGTT.
The hemoglobin A1c is not good way to diagnose diabetes. It is a good tool to continue to assess glucose control in someone with verified diabetes.
There is no way to prevent type 1 diabetes, but there are research programs. Given the family history of the cousins and uncles

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Input Text: Read the passage below and choose the right answer to the following question (choices are more or less ):

With a higher concentration of hydrogen ions, a solution is more acidic but has a lower pH.


Eric measures 20 hydrogen ions per 100ml in one solution. Another solution has 30 hydrogen ions per 100ml. The solution with more hydrogen ions is more or less acidic?

Target Text: more

#### Retrieved Documents ####

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Retrieved Text: The solute is the substance that is present in the smaller amount. The solvent is the substance that is present in the larger amount. Either may be a solid, liquid or gas although some solute/solution combinations are more common. A concentrated solution has a relatively large quantity of s specific solute per unit amount of solution, a dilute solution has a relatively small quantity of the same solute per unit ammount of solution. Solubility is a measure of how much solute will dissolve in a given amount of solvent and a given temperature. A solution that can exist in equilibrium with undissolved solute is a saturated solution. A solution whose concentration corresponds to the solubility limit is therefore saturated. If the concentration of solute is less than the solubility limit, it is unsaturated. Under carefully controlled conditions, a solution can be produced in which the concentration of solute is greater than the normal solubility limit. such a solution is said to be supersaturated. Miscible and immiscible are terms usually limited to solutions of liquids in liquids. If two liquids dissolve in each other in all proportions they are said to be miscible. If two liquids are insoluble in each other, they are said to be immiscible.
The dissolving process depends on surface area. A finelydivided solid offers more surface area per unit of mass than a coarsly divided solid. Therefore a finely divided solid dissolves more rapidly.
In a still solution, concentration builds up around the solute surface, causing a higher re-crystallization rate than would be present ifthe

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Retrieved Text: Home>>Lab techniques>>How does a pH meter work?
pH is defined as the negative logarithm of the hydrogen ion concentration of an aqueous solution. While this may sound complicated, in very simple terms, pH is a numerical value which quantifies the acidity or basicity of a solution. The number represents the number of hydrogen ions a particular substance can release in a solution. On the pH scale, a pH of 7 is considered to be neutral. A solution with pH 0-7 is considered to be acidic and above 7, till 14, is said to be a basic solution. In biological systems, pH is of utmost importance. Most biomolecules in our body, function optimally because of a carefully adjusted pH. Even in experimental systems, it is essential to maintain the desired pH to obtain accurate results. Hence, in biological experiments, pH is carefully monitored using equipment known as the pH meter.
The pH meter is a pH-responsive electrode, which measures the hydrogen-ion activity in a solution, and conveys the information to a voltmeter. The equipment consists of two glass tubes, each containing one electrode, a reference electrode and a sensor electrode. The reference electrode is made of a saturated KCl solution, whereas the sensor electrode contains a buffer solution of pH 7 and a silver wire coated with silver chloride is immersed in both these solutions. The sensor electrode has a bulb at the end, which is made of porous glass coated with silica and metal salts.
To measure the pH of a solution, this pH meter is dipped into the

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Retrieved Text: When it comes to learning about hydroponics and aquaponics, it’s likely that you’ll run into a few unfamiliar terms. In particular, there’s a lot of mumbo-jumbo about pH—we know it’s important and we know that it affects the way our plants grow in the system. But what exactly does that mean; why does it have such a big impact on the success of our farms? Let’s dig into the chemistry a bit.
pH is a measure of acidity, which matters because nutrients are more or less available at different levels of acidity. That means you’ll need to find the sweet spot on the pH scale where all of the nutrients are available, and the plants are getting what they need.
pH is represented by a scale that ranges from 0 to 14 (0 being the most acidic and 14 being the most basic). The term “pH” stands for “potential hydrogen” because hydrogen ions (H+) and hydroxide ions (OH-) are what cause a solution to be basic or acidic. pH tests measure the concentration of these two substances in a solution. Because there are so many, measuring a number of hydroxide or hydrogen ions is not practical, so instead, pH is measured on a logarithmic scale (we’ll get to that shortly).
This is where things get more complicated. As you know, water is made up of hydrogen and oxygen. Two hydrogens, in fact. Pure water has a pH of 7, which means that it has an equal number of hydrogen and hydroxide ions because nothing else is in the water

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Retrieved Text: Do chemistry - this might happen!
In high school, chemistry was my least favourite science subject. Physics was cool, because it was about how things moved and bounced and crashed, and this included planets and stars and stuff. Biology was fun because it was about animals and plants and how they interacted, and that was always an endless source of fascination. And geology was about the Earth and oceans and mountains and, most importantly, volcanoes, which were about the coolest thing I could imagine apart from planets. Chemistry seemed mostly to be about washing glassware, and those little test tubes you get in high school are darn near impossible to wash properly.
Chemistry involved Bunsen burners and heating things up, which always, according to my teacher, carried the risk of doing it wrong and splashing hot acid or whatever it was all over your face. You could mix things wrong, or measure them wrong, and your experiment wouldn't work. And reactions generated weird gases that could kill you if you inhaled them, so you had to use fume cupboards to avoid dying right there and then in your science classroom. Chemistry was a dangerous, inexact, difficult, mess that didn't work half the time. And the theory side of it was the dull balancing of reaction equations, which would have been trivially simple algebra if not for the seemingly completely arbitrary additional rules concerning valences that were apparently added for no other reason than to make it harder.
Looking further back, it was odd how it came to this, since

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Retrieved Text: As you know, potassium hydroxide, ##"KOH"##, is a strong base and hydrochloric acid, ##"HCl"##, is a strong acid, which means that they will both dissociate completely in aqueous solution to form hydroxide anions, ##"OH"^(-)##, and hydrogen cations, ##"H"^(+)##, respectively.
The hydrogen cations will actually exist as hydronium ions, ##"H"_3"O"^(+)##, in aqueous solution, but you can represent them as ##"H"^(+)## if you want.
These ions will then each other to form water. That is what your reaction is all about - how many hydroxide anions and how many hydrogen cations are present in solution.
The key to this problem is the that exists between these two ions in the balanced chemical equation.
So, one mole of hydroxide anions will react with one mole of hydrogen cations to form one mole of water.
This tells you that you need equal numbers of moles of strong base and strong acid to reach complete neutralization.
This means that in order to neutralize the acid, you need to have ##0.5005## moles of strong base.
Q: How does a solute differ from a solvent?
Q: How can I find the percent composition of (NH4)2S?

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Retrieved Text: Definition - What does Acid mean?
An acid is a chemical that releases hydrogen ions when it is dissolved in water. When placed in water, the aqueous solution that results will react with bases and some metals to form salts. Acids have a pH level of less than 7, have a sour taste, and will turn blue litmus paper red.
Acids exist in two main types, strong and weak. Strong acids have the property of fully dissolving in a solution, while weak acids will only partially dissolve in a solution. When exposed to water, all acids produce hydrogen ions. Strong acids tend to have a higher concentration of hydrogen ions than weak acids.

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Retrieved Text: Svante Arrhenius was the Swedish scientist who first defined acids and bases.
Strength of an acid/base refers to its ionisation (dissociation) ability; in acids its their ability to donate a proton, and in bases its their ability to accept a proton (and hence form OH- ions).
Strength is hence correlated to electrolytic rating, as ionisation correlates with losing/gaining electrons. And the dissolved species of these acids/bases exist as ions in solution.
Bronsted acids can release more than one proton (H+ ion). These release one proton per hydrogen atom in the acid.

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Retrieved Text: What is an Arrhenius Acid?
What Happens When an Acid & a Base Are Combined?
Chemists have three separate theories for what constitutes an acid and a base, but there's no disagreement on the fact that they neutralize each other. When they combine in a water solution, they produce a salt. Acids and bases can combine in other ways, however, and when they do, the product isn't always a salt. For example, when you add zinc to ammonia, the reaction results in a complex ion. Until the introduction of the Lewis theory of acids and bases, this wouldn't even have been considered an acid/base reaction.
In aqueous solutions, acids and bases combine to neutralize each other and produce a salt. Acid-base reactions that do not occur in water usually also produce salts, but they may also produce complex ions.
According to a theory advanced by Svante Arrhenius. a Nobel prize-winning physicist and chemist, an acid in solution donates an H+ ion in water. The ions don't float around freely, but instead attach themselves to water molecules to form hydronium ions (H3O+). The pH of a solution, which refers to the "power of hydrogen," is a measure of the number of these ions present. pH is a negative logarithm of concentration, so the lower the pH, the higher the concentration of these ions, and the more acidic the solution. Bases, on the other hand, donate hydroxide (OH-) ions. When a solution has a preponderance of hydroxide ions, its pH is above 7 (the neutral point), and the solution is alkaline. Acids

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Retrieved Text: Does Sodium Hydroxide Kill Plants?
Sodium hydroxide or lye is a simple ionic compound with the chemical formula NaOH, meaning that it has one atom of sodium for each atom of oxygen and atom of hydrogen. This compound is found in oven and drain cleaners and finds innumerable uses in industry. Despite all this, however, sodium hydroxide is not a compound you want to put on your plants.
Sodium hydroxide is strongly basic. When it dissolves in water, it releases hydroxide ions, which act as base because they can pick up hydrogen ions to become H2O. As sodium hydroxide concentration increases, the hydrogen ion concentration decreases, and the pH of the solution increases. Drain cleaners and oven cleaners or concentrated lye sold at some hardware stores will typically have a pH from 13 to 14 -- a highly alkaline pH.
A strong solution of lye will do one of two things, depending on how it's applied. If you were to pour it on the soil, for instance, it would raise soil pH. The extent to which the soil pH changes will depend on the buffer capacity and the amount and concentration of lye applied. If soil pH did increase substantially, however, many nutrients the plant needs would become unavailable to it -- iron being just one example. Starving the plant of nutrients could kill it and at the very least would stunt its growth.
If the sodium hydroxide were directly applied, by contrast, it would harm the plant in a much more immediate way. Concentrated sodium hydroxide is a very

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Retrieved Text: If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
If the volume of the container were reduced, what would happen to the rate of the reaction?
Reducing the volume of the container increases pressure. This results in a higher frequency of gas particle collisions, thereby increasing the rate of the reaction.
Consider the following equation for the production of ammonia gas from hydrogen gas and nitrogen gas.
If the volume of the vessel containing hydrogen and nitrogen is decreased, the production of ammonia __________.
Since decreasing the volume of the container has the effect of increasing pressure, equilibrium is shifted to the right. An increase in pressure has the result of favoring the side of the reaction with fewer moles of gas. (According to the balanced equation, there are 4 moles on the reactant side as opposed to 2 moles on the product side).
Barium fluoride dissolves in solution according to the following equation.
Enough BaF2 is added to create a saturated liter of aqueous solution.
Suppose that 1M NaF is added to the solution, such that it does not change the volume of the solution. What would you expect to change as a result of the addition of NaF?
The pH of the solution will decrease.
The solubility product constant will decrease.
The solubility of BaF2 will decrease.
By adding NaF to the equation, 1M of F- ions are added to the solution. Thinking in terms of Le

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Retrieved Text: The latest reviewed version was checked on 13 September 2018. There are 3 pending changes awaiting review.
Use Sodium Nitroprusside. In the presence of sulphide ions a deep violet coloration is formed. [Fe(CN)5NOS]4- complex anion formed in the presence of sulphide ions is the cause for this coloration.colouration is important.
If a sulfide solution is reacted with silver nitrate, it forms a black precipitate of Ag2S.
When H2S is bubbled through a solution of Sodium sulphite or Sodium bisulphite, a white turbidity of sulfur is seen. What happens is, the S atom in sulphite/bisulphite (Oxidation state +4) and in H2S (Oxidation state -2) have coproportionated to give molecular sulfur in zero oxidation state. The reaction can be viewed as the reverse of a disproportionation reaction.
When H2S is bubbled through acidified KMnO4 solution, it decolorises and a white turbidity is observed. This is because, the powerful oxidizing agent permanganate ion has oxidized the sulfide ion (-2) to zero oxidation state. In doing so, the permanganate ions themselves reduce to Mn2+ ions, thus the purple/violet/pink color of the solution is diluted and eventually fades away as the manganous ions do not impart any color to the solution.
The nitrite ion gives several reactions based on its redox properties.
When it reacts with the I3- anion, the nitrite ion reduces itself to nitric oxide. The student should check the oxidation states of nitrogen in both the cases.
The yellow color of the I3- ions changes to a greenish tinge which later turns violet. This observation is made in the presence of an oxidizing agent which

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Score: 68.562836
Retrieved Text: Roundup Xtend™ with VaporGrip® Technology is a glyphosate and dicamba pre-mix product with low volatility properties. XtendiMax® with VaporGrip® Technology has been developed and is a dicamba straight-good product with low volatility properties. In older dicamba formulations, dicamba ions (Dc-) are present in solution, combine with free hydrogen ions (H+) to form volatile dicamba acid (DCH). VaporGrip® Technology prevents dicamba ions (Dc-) from combining with hydrogen ions (H+), significantly reducing volatility.

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Retrieved Text: The atomic number of an atom is A. the number of protons in the atom.B. the number of neutrons in the atom.
C. the number of protons and electrons in the atom. D. the number of protons and neutrons in the atom. E. None of these choices are correct.
LO: 02.01.03 Relate atomic structure to the periodic table of the elements.
The smallest functional unit and associated structures of a living organism are A. atoms and their protons, neutrons and electrons.
B. molecules and their atoms, bonds and electrons. C. proteins and amino acids.
D. cells with nucleus, mitochondria and ER. E. water made of hydrogen and oxygen.
LO: 02.01.01 Describe the general structure of atoms and their constituent particles.
With an atomic mass of 16 and an atomic number of 8, it follows that oxygen __X__ has eight electrons.
__X__ can readily form bonds with 2 other atoms.
The nucleus of an atom is composed of A. protons.
D.protons and neutrons.E. protons and electrons.
The first, inner-most energy shell of an atom A. can have a maximum of 8 electrons.
B.can have a maximum of 2 electrons.C. is called the 2p orbital.
D. is called the 1s orbital and can have a maximum of 8 electrons. E. is called the 2p orbital and can have a maximum of 2 electrons.
LO: 02.01.02 Discuss the way electrons occupy electron shells that surround the nucleus.
Tritiated hydrogen (3H) differs from hydrogen (1H) in that A. 3H has 2 more protons than1H.
B. 3H has 2 more electrons than1H.C.3H has 2 more neutrons than1H.
D. 3H has the same number of neutrons as1H.
E. 3H has

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Retrieved Text: Definition, methods, meters: This page gives you an introduction to pH measurement and appropriate solution for your application.
The H+ is called hydrogen ion or proton, the OH- is the so-called hydroxide ion.
pH is the mathematical description of the activity of the hydrogen ions. It goes from about -1 to about + 15. Corresponding to this scale liquids are classified as acid, alkaline or neutral: If a solution is neither acid nor alkaline it is called neutral. This corresponds on the scale to pH 7. Acid means a high activity of hydrogen ions and pH lower than 7. Alkaline solutions are charaterized by a lower activity of the hydrogen ions respectively a higher activity of the hydroxide ions and a pH above 7. The grahic below illustrates with some examples the pH scale.
The pH scale is a logarithmic scale. The change of one unit means in fact a ten times increase or decrease of the activity of the hydrogen ions. This explains why the corrosiveness with increasing distance from the neutral point is strongly growing.
For determination or measurement of the pH it is necessary to have suitable equipment. This is provided by electro chemical measurement systems, litmus paper, indicators and photometers. Accurate results for pH are only provided by the electro chemical methods. The appropriate sensor is the pH electrode.
The pH electrode is an electrochemical sensor which consists of a measurement electrode and a reference electrode.The measurement electrode is made of a special glass which is due to its surface properties very sensitive for hydrogen ions. It

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Retrieved Text: Motara, Hasina (2011) Isothermal Titration Calorimetric Studies of Complexation Reactions. Doctoral thesis, University of Huddersfield.
The objective of this work has been to study the binding of metal ions to complex ligands expressing two or more metal binding sites, in terms of the thermodynamics of the binding events, and to use this information to contribute to the understanding of both the metal binding processes and the properties of the metal/ligand complexes. Two ligands have formed the basis of the study, one a naturally occurring enzyme and the other a newly synthesised ligand with two distinct binding sites (to form supramolecular complexes). The principle technique used to determine thermodynamic parameters has been isothermal titration calorimetry (ITC).
The first system studied involved the enzyme β-lactamase II from Bacillus cereus 569/H/9 (BcII). The binding of zinc (II), cobalt (II) and cadmium (II) was investigated in aqueous solution at pH’s from 5.2 to 7.2. By using three or more buffers at each pH it has been possible to determine not only the binding constants of the metal ions at these pH’s but also the molar enthalpies of binding (and hence molar entropies). In addition, the dissociation of hydrogen ions from the enzyme on metal binding was also observed. In the case of all three metal ions, one metal ion per enzyme appears to bind at low pH and two metal ions at high pH (within the pH 5.20-7.20 range). In the case of zinc and cobalt ions two metal ions seem to bind per mole of enzyme in a cooperative mechanism. In

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Retrieved Text: precipitation gold cyanide solution. precipitation of gold from aqua regia with sodium. extraction of gold for preparing ornaments. investing gold mining companies. gold mineral machine series kyf flotation tank in yantai. ... Prev: rock win mining machine for sale Next: crushing machine crusher fondant.
To make aqua regia solution you will need Hydrochloric Acid and Nitric Acid. These are sold separately from this kit. These are sold separately from this kit. This kit is a convenient way to obtain some of the chemicals used in scrap gold recovery.
Aqua regia is an extremely corrosive mixture of nitric acid and hydrochloric acid in the molar ratio of 1:3. Aqua Regia is a yellow - orange fuming liquid. It is used as an etchant, for some analytical chemistry procedures,and to refine gold.
Detailed Product Description: This kit provides the constituents necessary to create 500ml of. Aqua Regia. This is an extremely powerful oxidizing solution prepared from concentrated Nitric Acid (69% HNO 3) and concentrated Hydrochloric. Acid (38% HCL).
One of the safest and most advanced aqua regia gold refining systems available. The Shor Aqua Regia Gold & Platinum Refining System is ideally suited for refining of electronic scrap as well as jeweler’s polishing and bench sweeps.
Aqua Regia Definition. Aqua regia is a mixture of hydrochloric acid (HCl) and nitric acid (HNO 3) at a ratio of either 3:1 or 4:1.It is a reddish-orange or yellowish-orange fuming liquid. The term is a Latin phrase, meaning "king's water".
Hot sale Coconut shell activated carbon price for gold. Add to Compare .. Hot sale solvent recovery

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Retrieved Text: Removal of hardness from water is called softening. The softening is done by ion exchange process. The ion exchange process works on the replacement of the calcium and magnesium ions in the water by an equivalent number of sodium ions.
This eliminates the unwanted charasteristic of hard water because the sodium salt neither form scale nor a scum with soap but only lather.The resin will take up the calcium ion to the extent of what sodium ions resin will have with it.
Therefore, to give new sodium ions to the resins, the cheapest and the easiest mean would be to pass the solution of sodium-chloride (common-salt) through the resin. The same resin can be used over and over again to produce soft water a - periodic dossage of sodium chloride (common-salt) solution. So, recurring cost in such process is only the cost of common salt.
PURIC systems use the basic ion exchange principle. With this principle, ions in solution, including metallic cations such as calcium (Ca ++) and anions such as chloride (Cl -) are exchanged for other ions such as hydrogen ie. (H +) and hydrdxyl (OH-) that are contained inside synthetic ion exchange resins. By passing the solution through columns of cation and anion exchange resin, all the ions can be exchanged, leaving only hydrogen and hydroxyl, which combine, leaving pure water. Alternatively, by suitable choice of ion exchange resin, only a portion of the ions can be selectively removed.
When their exchange capacity has been exhausted,ion exchange resins can be regenerated.
Today, although the use of ion exchange

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Retrieved Text: All ion selective electrodes are similar in operation and use. They differ only in the process by which the ion to be measured moves across the membrane and by which other ions are kept away. Therefore electrode interferences must be discussed in terms of membrane materials.
Glass electrodes and solid-matrix/liquid-ion exchange electrodes both function by an exchange of mobile ions within the membrane, and ion exchange processes are not specific. Reactions occur among many ions with similar chemical properties, such as alkali metals, alkaline earths, or transition elements. Thus, a number of ions can produce a potential when an ion selective electrode is immersed in a solution. Even the pH glass electrode responds to sodium ions at a high pH (low hydrogen ion activity). Fortunately, an empirical relationship can predict electrode interferences, and a list of selectivity ratios for the interfering ions is available from the manufacturers' specifications or other chemical publications.
Solid-state matrix electrodes are made of crystalline materials. Interferences resulting from ions moving into the solid membrane are not expected. Interference usually occurs from a chemical reaction with the membrane. An interference with the silver-halide membranes (for chloride, bromide, iodide, and cyanide activity measurements) involves a reaction with an ion in the sample solution, such as sulfide, to form a more insoluble silver salt.
A true interference produces an electrode response that can be interpreted as a measure of the ion of interest. For example, the hydroxyl ion, OH", causes a response with the fluoride electrode at fluoride levels below 10 ppm. Also, the hydrogen ion, H+,

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Retrieved Text: 5.	What is a strong acid?
A: Strong acids are acids that undergoes complete ionization of hydrogen ions in water.
6.	What is a weak acid?
A: Weak acids are acids that undergoes partial ionization of hydroxide ions in water.
A: An indicator is a chemical substance added to determine the pH of a substance.
8.	What are the common indicators?
A: Universal indicator - Red at pH 1 for strong acids, Orange and yellow for weak acids, Green for neutral solution, blue for weak alkali and violet for strong alkali.
9.	What exactly is neutralization?
A: Process where acids and bases react with form salt and water only.
10.	What is a base?
A: A substance that reacts with acids to form salt and water. When it is soluble, it forms an alkali.
11.	What are the products when acids react with metals?
A: Salt and hydrogen gas.
12.	What are the products when acids react with metal carbonate?
A: Salt, water and carbon dioxide.
13.	What are the products when acids react with metal oxide, also known as a base?
14.	What are the products when acids react with metal hydroxide, also known as a base?
15.	What is produced when bases dissolved in water?
16.	Write the ionization equations of all common acids, including state symbols.
17.	Write the ionization equations of common alkalis, including state symbols.
A: NaOH --> Na+ + OH- or Ca(OH)2 --> Ca2+ + 2OH- or NH4OH --> NH4+ + OH- and again all state symbols are aq.
18.	Describe a simple test to prove that water is needed for the ionization of acids.
A: Dissolve nitric acid into water and ethanol separately. Connect a light bulb and a battery to the solution. The

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Retrieved Text: Envodil Mop* is a combination of Hydrogen Peroxide and Silver Nitrate with cleansing action used for cleaning, mopping and surface disinfection. Envodil Mop* is an effective, eco friendly and completely biodegradable solution.
Purified Water IP q. s.
Recommended Dilution: 10% solution (100ml Envodil Mop* and 900ml water) for mopping procedures.
Use 2 bucket system to get better results.

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Retrieved Text: Often referred to as the "Holy Grail" of energy storage, the economical and efficient conversion of water into hydrogen and oxygen with electricity (electrolysis) has been a goal of scientists for decades.
The amount of energy stored per kilogram of hydrogen is roughly two and a half times larger than natural gas and, most importantly, the only byproduct of burning hydrogen for energy is water. In the future, hydrogen could power everything from cars to buildings—but producing hydrogen from water on a global scale could put a strain on purified water sources that are needed for drinking, as well as many other industrial processes.
With this reality in mind, a team of chemists at Stanford University have developed a way to convert seawater, which makes up about 97 percent of water on Earth, into hydrogen. Findings are published in PNAS.
A typical electrolyzer consists of two metal electrodes—anode and cathode—that are immersed in an electrolyte solution and separated by a membrane. When electricity is passed through the solution, oxygen bubbles off the anode and hydrogen bubbles off the cathode. To minimize the amount of energy required to liberate the hydrogen from water, both electrodes are typically coated with a catalyst. The device developed by the Stanford team has many similarities to commercial electrolyzers—but with critical tweaks that allow it to use seawater instead of purified water.
As anyone who has been unfortunate enough to swallow a mouthful of seawater knows, it is salty. Salt, or sodium chloride if you remember high school chemistry, is composed of negatively charged chloride atoms

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Retrieved Text: Thus, as may be expected, chemistry is very relevant to the study of electricity.
and most of the rest is argon Ar, whose atoms don't combine.
Among the many chemical compounds. water has a unique role. On Earth, of course, it can be liquid, solid (ice) or gas (steam), and the existence of liquid water seems essential to life.
Although at first this seemed like a strange idea, today it is quite well understood. Many chemical molecules are formed when atoms share electrons, but molecules such as those of NaCl are different. There, the sodium atom (Na) gives up an electron to the chlorine (Cl), creating ions Na+ and Cl-, which in solid salt are held together by their electric attraction ("ionic bond"). Water, however, greatly weakens electric forces (on the atomic scale), allowing some ions to drift free whenever salt is dissolved in water, and allowing the water to conduct electricity.
The smallest atomic positive ion is the proton, the nucleus of hydrogen. Substances which when dissolved in water produce ions of hydrogen are known as acids and any such solution (e.g. HCl, H2SO4 ) has a sour taste. Of course, the fraction of acid molecules which actually breaks up into ions in a water solution can vary--it is large in "strong" acids and small in "weak" acids. Even in pure water a tiny fraction of the molecules is split up into ions H+ and (OH)– ("hydroxyl") at any time. The degree of "sourness" depends on the concentration of the acid in the water and on its strength; carbonated

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Retrieved Text: 2007-08-30 Assigned to BOC EDWARDS, INC. reassignment BOC EDWARDS, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: THE BOC GROUP, INC.
2008-03-18 Assigned to EDWARDS VACUUM, INC. reassignment EDWARDS VACUUM, INC. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: BOC EDWARDS, INC.
A process for fluoride removal from wastewater streams produced during industrial operation for further industrial use or to comply with environmental regulations. The process segregates the removal of fluoride and fluorosilicate ions, from the totality of ions in the waste water stream, thus improving treatment efficiency and reducing costs. Ion-exchange chromatography is used to remove the fluoride and fluorosilicate ions by passing the wastewater stream through one or more columns that contain a charged resin which selectively binds cations/anions in the stream. The fluoride ions are washed from the column and then collected for removal or use in other processes.
Many industrial operations utilize fluoride, often as hydrofluoric acid or as fluoride salts such as ammonium fluoride. For example, alumina and silica etching, cleaning, etc. and semiconductor production utilize large amounts of hydrofluoric acid, and other fluoride compounds. As a regulated element in water discharge, for reasons well known in the art, the wastewater generated needs to be processed for fluoride ion removal. Additionally, when using hydrofluoric acid (HF), semiconductor manufacturers often require an ultra-pure hydrofluoric acid.
The typical semiconductor manufacturer may produce an average of 10,000 gallons per day of mixed acidic fluoride waste. The production of such vast quantities of fluoride ion waste, however, presents significant disposal problems. Fluoride wastes are becoming subject to

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Retrieved Text: During charging in the new battery, manganese ions (red) from the manganese sulfate electrolyte solution deposit on the carbon-fiber-based fabric (green) at the cathode while the platinum catalyst (yellow) at the anode fabric (purple) produces hydrogen gas from water. The process is reversed during discharge.
A new battery made of manganese and hydrogen could be easily scaled up to store energy for the grid, researchers say. The battery houses a large amount of energy, lasts a long time, and could be inexpensive enough for the job.
Most current battery technologies fall short in at least one area. Lithium-ion batteries that power laptops and electric cars have energy densities of over 200 Wh/kg, but they cost more than twice the DOE requirements. Redox-flow batteries are also expensive. Meanwhile, lead-acid batteries are cheap, but they last only 500 cycles and their energy densities are subpar. Researchers have recently made low-cost batteries with aqueous solutions of zinc and sodium ions as electrolytes, but they also suffer from low energy density and short cycle life.
A prototype manganese-hydrogen battery cell (photo, right) consists of a cathode (green) inside of a steel cylinder and a small anode (purple) in the middle, with the space in between filled with electrolyte.
Cui’s group turned to plentiful manganese. He says the new battery meets all the critical needs for the grid. It has the potential to be low cost because manganese and hydrogen are abundant. It has an energy density of around 140 Wh/kg, thrice that of lead-acid. And it boasts a very long life of more than

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Retrieved Text: I will tell you right now, a homemade chlorine battery is not going to be as cost effective as commercial batteries. In the nanny state it is almost impossible to get pure enough chemicals to really experiment. However, I think it is important for the sustainable power types to understand what is going on within their system. This allows them to make informed decisions when they buy their batteries.
In a true grid down collapse, i.e. Mad Max scenario, the ability to make batteries from scrounged materials may come in handy. Now before you get too excited, if you get one volt per battery cell you are doing extremely well.
It will take many of these cells to get any usable energy. This is not a cost effective way to power your home.
In the video we make a battery using a mason jar, copper, aluminum, and chlorine bleach.
Basically, any two different kinds of metal can be placed in a conducting solution and you get a battery. In some schools they still teach an experiment that involves inserting copper and zinc strips into a lemon or a potato to make a battery.
Once you get the basic chemistry down, feel free to experiment. I have seen instructions for making large cells from aluminum soda cans riveted together and inserted into long PVC pipes. Right now I am experimenting with PVC pipe, grounding rod, and aluminum pipe.
If you want to see the procedure to make a chlorine battery, please watch the video.
As promised in the video, this article will discuss the

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Retrieved Text: In this chapter of Redox Reaction, you will be learning what precisely the term ‘redox’ means. This topic is short, but a significant one because it is the foundation of more challenging topics later on. A clear understanding of this topic is needed to understand reaction mechanisms for future topics in O and A Levels.
The term ‘redox’ is used to describe any type of chemical reactions. We can characterise any chemical reactions into two main groups: redox reaction and non-redox reaction.
Redox reaction is a chemical reaction where reduction and oxidation have occurred.
On the other hand, a non-redox reaction is where neither reduction or oxidation have occurred.
Important note: If a chemical reaction is a redox reaction, both oxidation and reduction must co-occur. In other words, whenever reduction occurs, oxidation must also occur in a same chemical reaction.
When both reduction and oxidation happens, we describe the overall reaction as a redox reaction.
Reduction and oxidation are key terms in this chapter. So what exactly is the meaning of reduction and oxidation?
(4) Experience an increase in oxidation state.
In the previous statement, ‘species’ can mean any chemical ions, atoms or compounds. Anyone of the four requirements would indicate an oxidation reaction.
When a species gains oxygen, it is said to be oxidised. For example, when zinc reacts with atmospheric oxygen to form zinc oxide, zinc is oxidised to form zinc(II) ions, and we say that oxidation occurs.
Carbon gained oxygen and is oxidised.
Aluminium gained oxygen and is oxidised.
Oxidation is also said to happen when a species loses hydrogen. For instance, when hydrogen sulfide

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Retrieved Text: I ammonia an ion when it is dissolved in water?
The anoxic layer also contains high concentrations of ammonia and phosphate. These chemicals are almost completely absent from the upper layer.
1. Is it technically correct to call ammonia (NH3?) an ion when it is dissolved in water. I understand that salt (NaCl) disassociates when dissolved in water. Does ammonia do something similar?
2. If ammonia did disassociate in water what does it disassociate into?
3. Does dissolution in water generally involve some kind of disassociation? Would the disassociated components generally be called ions? For instance does glucose disassociate when dissolved in water or for the most part are there just complete glucose molecules floating in water in a glucose solution.
I have more questions but for the most part I don't know enough to ask good questions on this. I am really looking for just a little general information about the nature of solutes and in particular how should the sentences in the Jellyfish Lake article linked to above be worded to be correct.
It is incorrect to call ammonia an ion. It is a molecule.
Ammonia does not dissociate, but it does ionize in solution to a small degree. NH3 + H2O <-> NH4+ + OH-. The degree depends on conditions, but is unlikely to be above 5%.
Only for ionic compounds (and acids). Glucose and ammonia are neither.
Thanks for the response. Could you confirm that I understand all this correctly?
1. Only a small percentage of the ammonia dissolved in water turns into ions so the use of the term "ammonia ions"

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Retrieved Text: Resistors in series R = R1+R2+R3+R4….
Rank Hydrogen, Covalent and Ionic by strength (strong, weak, very weak) Covalent – Strong. Ionic – Weak. Hydrogen – Very Weak.
Hydrogen Bonds Weak electrical attractions. Takes place between the ends of molecules and H. (ex. holds water molec. together in solution).
Lipids C,H,O present, but much less O than either, C to H ratio 1:2. example is lauric acid (C12, H24, O2), fats, oils, waxes.
Buffer Removes or replaces hydrogen ions in solution. Buffers maintain the PH within normal limits.
Proteoglycans (carb-protein combination) large polysaccharides linked by peptide chains. Important thickening agent for tissue fluids.

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Retrieved Text: The electrolysis of water yields oxygen and hydrogen gases and simple calculations estimate the charge of the ions.
Do not ignite the hydrogen gas directly in the burettes but sample it as described below.
0.4 M sulfuric acid is not hazardous.
The Worcester voltameter kit consists of two 250-ml burettes mounted vertically so that they will fit inside a tall gas jar (see diagram). The electrodes consist of stiff wires covered with plastic insulation except where they are within the inverted burettes. Ideally, these tips are plated with platinum. The advantage of this design (which many schools have) is that the glass items are standard and easily replaced when broken.
The Hofmann voltameter is an alternative piece of apparatus. It is expensive and easily broken, but many schools have one. There is also a mini-version consisting of two small test-tubes in a small trough.
Although this is traditionally described as 'electrolysis of water', showing that an electric current can split water into two volumes of hydrogen to one of oxygen, it is a little more complicated. Pure water contains few ions so the process is very slow. To obtain results in a reasonable time, sulfuric acid or another electrolyte is added. See the CLEAPSS Laboratory Handbook (section 11) for a fuller discussion (in colour on the CD). For the oxygen problem, see teaching note 2.
In this context, the object is to indicate that each hydrogen ion is associated with only half the electric charge associated with each copper ion in the electrolysis of copper.
a The circuit is connected as shown.
b Only

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Retrieved Text: Detection of heavy metals via fluorescence has attracted increasing attention. Herein, we report a novel copper(II) ion (Cu2+) sensor using fluorescent polydopamine (FPDA). Dopamine is easily oxidized to polydopamine by oxygen in alkaline solution, and oxidized polydopamine does not fluoresce. However, under a nitrogen atmosphere, FPDA can be produced by adding hydrogen peroxide into a dopamine solution in the presence of Cu2+ ions. The fluorescence intensity of FPDA is strongly dependent on the concentration of Cu2+ ions. At higher concentrations of Cu2+ ions, the photoluminescence intensity of FPDA also increases at a higher rate. FPDA exhibited a highly sensitive and selective response to Cu2+ ions over other ionic competitors in the biological milieu, achieving a detection limit as low as 1 nmol L-1 (nM). This study shows that the method can be used for monitoring in vivo Cu2+ ions owing to the distinct properties of FPDA such as strong fluorescence signal and biocompatibility.

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Input Text: Read the passage below and choose the right answer to the following question (choices are more or less ):

With a higher concentration of hydrogen ions, a solution is more acidic but has a lower pH.


Eric measures 20 hydrogen ions per 100ml in one solution. Another solution has 30 hydrogen ions per 100ml. The solution with less hydrogen ions is more or less acidic?

Target Text: less

#### Retrieved Documents ####

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Retrieved Text: The solute is the substance that is present in the smaller amount. The solvent is the substance that is present in the larger amount. Either may be a solid, liquid or gas although some solute/solution combinations are more common. A concentrated solution has a relatively large quantity of s specific solute per unit amount of solution, a dilute solution has a relatively small quantity of the same solute per unit ammount of solution. Solubility is a measure of how much solute will dissolve in a given amount of solvent and a given temperature. A solution that can exist in equilibrium with undissolved solute is a saturated solution. A solution whose concentration corresponds to the solubility limit is therefore saturated. If the concentration of solute is less than the solubility limit, it is unsaturated. Under carefully controlled conditions, a solution can be produced in which the concentration of solute is greater than the normal solubility limit. such a solution is said to be supersaturated. Miscible and immiscible are terms usually limited to solutions of liquids in liquids. If two liquids dissolve in each other in all proportions they are said to be miscible. If two liquids are insoluble in each other, they are said to be immiscible.
The dissolving process depends on surface area. A finelydivided solid offers more surface area per unit of mass than a coarsly divided solid. Therefore a finely divided solid dissolves more rapidly.
In a still solution, concentration builds up around the solute surface, causing a higher re-crystallization rate than would be present ifthe

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Retrieved Text: Home>>Lab techniques>>How does a pH meter work?
pH is defined as the negative logarithm of the hydrogen ion concentration of an aqueous solution. While this may sound complicated, in very simple terms, pH is a numerical value which quantifies the acidity or basicity of a solution. The number represents the number of hydrogen ions a particular substance can release in a solution. On the pH scale, a pH of 7 is considered to be neutral. A solution with pH 0-7 is considered to be acidic and above 7, till 14, is said to be a basic solution. In biological systems, pH is of utmost importance. Most biomolecules in our body, function optimally because of a carefully adjusted pH. Even in experimental systems, it is essential to maintain the desired pH to obtain accurate results. Hence, in biological experiments, pH is carefully monitored using equipment known as the pH meter.
The pH meter is a pH-responsive electrode, which measures the hydrogen-ion activity in a solution, and conveys the information to a voltmeter. The equipment consists of two glass tubes, each containing one electrode, a reference electrode and a sensor electrode. The reference electrode is made of a saturated KCl solution, whereas the sensor electrode contains a buffer solution of pH 7 and a silver wire coated with silver chloride is immersed in both these solutions. The sensor electrode has a bulb at the end, which is made of porous glass coated with silica and metal salts.
To measure the pH of a solution, this pH meter is dipped into the

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Retrieved Text: When it comes to learning about hydroponics and aquaponics, it’s likely that you’ll run into a few unfamiliar terms. In particular, there’s a lot of mumbo-jumbo about pH—we know it’s important and we know that it affects the way our plants grow in the system. But what exactly does that mean; why does it have such a big impact on the success of our farms? Let’s dig into the chemistry a bit.
pH is a measure of acidity, which matters because nutrients are more or less available at different levels of acidity. That means you’ll need to find the sweet spot on the pH scale where all of the nutrients are available, and the plants are getting what they need.
pH is represented by a scale that ranges from 0 to 14 (0 being the most acidic and 14 being the most basic). The term “pH” stands for “potential hydrogen” because hydrogen ions (H+) and hydroxide ions (OH-) are what cause a solution to be basic or acidic. pH tests measure the concentration of these two substances in a solution. Because there are so many, measuring a number of hydroxide or hydrogen ions is not practical, so instead, pH is measured on a logarithmic scale (we’ll get to that shortly).
This is where things get more complicated. As you know, water is made up of hydrogen and oxygen. Two hydrogens, in fact. Pure water has a pH of 7, which means that it has an equal number of hydrogen and hydroxide ions because nothing else is in the water

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Retrieved Text: Do chemistry - this might happen!
In high school, chemistry was my least favourite science subject. Physics was cool, because it was about how things moved and bounced and crashed, and this included planets and stars and stuff. Biology was fun because it was about animals and plants and how they interacted, and that was always an endless source of fascination. And geology was about the Earth and oceans and mountains and, most importantly, volcanoes, which were about the coolest thing I could imagine apart from planets. Chemistry seemed mostly to be about washing glassware, and those little test tubes you get in high school are darn near impossible to wash properly.
Chemistry involved Bunsen burners and heating things up, which always, according to my teacher, carried the risk of doing it wrong and splashing hot acid or whatever it was all over your face. You could mix things wrong, or measure them wrong, and your experiment wouldn't work. And reactions generated weird gases that could kill you if you inhaled them, so you had to use fume cupboards to avoid dying right there and then in your science classroom. Chemistry was a dangerous, inexact, difficult, mess that didn't work half the time. And the theory side of it was the dull balancing of reaction equations, which would have been trivially simple algebra if not for the seemingly completely arbitrary additional rules concerning valences that were apparently added for no other reason than to make it harder.
Looking further back, it was odd how it came to this, since

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Retrieved Text: As you know, potassium hydroxide, ##"KOH"##, is a strong base and hydrochloric acid, ##"HCl"##, is a strong acid, which means that they will both dissociate completely in aqueous solution to form hydroxide anions, ##"OH"^(-)##, and hydrogen cations, ##"H"^(+)##, respectively.
The hydrogen cations will actually exist as hydronium ions, ##"H"_3"O"^(+)##, in aqueous solution, but you can represent them as ##"H"^(+)## if you want.
These ions will then each other to form water. That is what your reaction is all about - how many hydroxide anions and how many hydrogen cations are present in solution.
The key to this problem is the that exists between these two ions in the balanced chemical equation.
So, one mole of hydroxide anions will react with one mole of hydrogen cations to form one mole of water.
This tells you that you need equal numbers of moles of strong base and strong acid to reach complete neutralization.
This means that in order to neutralize the acid, you need to have ##0.5005## moles of strong base.
Q: How does a solute differ from a solvent?
Q: How can I find the percent composition of (NH4)2S?

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Retrieved Text: Definition - What does Acid mean?
An acid is a chemical that releases hydrogen ions when it is dissolved in water. When placed in water, the aqueous solution that results will react with bases and some metals to form salts. Acids have a pH level of less than 7, have a sour taste, and will turn blue litmus paper red.
Acids exist in two main types, strong and weak. Strong acids have the property of fully dissolving in a solution, while weak acids will only partially dissolve in a solution. When exposed to water, all acids produce hydrogen ions. Strong acids tend to have a higher concentration of hydrogen ions than weak acids.

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Retrieved Text: Svante Arrhenius was the Swedish scientist who first defined acids and bases.
Strength of an acid/base refers to its ionisation (dissociation) ability; in acids its their ability to donate a proton, and in bases its their ability to accept a proton (and hence form OH- ions).
Strength is hence correlated to electrolytic rating, as ionisation correlates with losing/gaining electrons. And the dissolved species of these acids/bases exist as ions in solution.
Bronsted acids can release more than one proton (H+ ion). These release one proton per hydrogen atom in the acid.

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Retrieved Text: What is an Arrhenius Acid?
What Happens When an Acid & a Base Are Combined?
Chemists have three separate theories for what constitutes an acid and a base, but there's no disagreement on the fact that they neutralize each other. When they combine in a water solution, they produce a salt. Acids and bases can combine in other ways, however, and when they do, the product isn't always a salt. For example, when you add zinc to ammonia, the reaction results in a complex ion. Until the introduction of the Lewis theory of acids and bases, this wouldn't even have been considered an acid/base reaction.
In aqueous solutions, acids and bases combine to neutralize each other and produce a salt. Acid-base reactions that do not occur in water usually also produce salts, but they may also produce complex ions.
According to a theory advanced by Svante Arrhenius. a Nobel prize-winning physicist and chemist, an acid in solution donates an H+ ion in water. The ions don't float around freely, but instead attach themselves to water molecules to form hydronium ions (H3O+). The pH of a solution, which refers to the "power of hydrogen," is a measure of the number of these ions present. pH is a negative logarithm of concentration, so the lower the pH, the higher the concentration of these ions, and the more acidic the solution. Bases, on the other hand, donate hydroxide (OH-) ions. When a solution has a preponderance of hydroxide ions, its pH is above 7 (the neutral point), and the solution is alkaline. Acids

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Retrieved Text: Does Sodium Hydroxide Kill Plants?
Sodium hydroxide or lye is a simple ionic compound with the chemical formula NaOH, meaning that it has one atom of sodium for each atom of oxygen and atom of hydrogen. This compound is found in oven and drain cleaners and finds innumerable uses in industry. Despite all this, however, sodium hydroxide is not a compound you want to put on your plants.
Sodium hydroxide is strongly basic. When it dissolves in water, it releases hydroxide ions, which act as base because they can pick up hydrogen ions to become H2O. As sodium hydroxide concentration increases, the hydrogen ion concentration decreases, and the pH of the solution increases. Drain cleaners and oven cleaners or concentrated lye sold at some hardware stores will typically have a pH from 13 to 14 -- a highly alkaline pH.
A strong solution of lye will do one of two things, depending on how it's applied. If you were to pour it on the soil, for instance, it would raise soil pH. The extent to which the soil pH changes will depend on the buffer capacity and the amount and concentration of lye applied. If soil pH did increase substantially, however, many nutrients the plant needs would become unavailable to it -- iron being just one example. Starving the plant of nutrients could kill it and at the very least would stunt its growth.
If the sodium hydroxide were directly applied, by contrast, it would harm the plant in a much more immediate way. Concentrated sodium hydroxide is a very

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Retrieved Text: If the reactants and/or products in a chemical reaction are gases, the reaction rate can be determined by measuring the change of pressure as the reaction proceeds. Consider the following reaction and pressure vs. reaction rate data below.
If the volume of the container were reduced, what would happen to the rate of the reaction?
Reducing the volume of the container increases pressure. This results in a higher frequency of gas particle collisions, thereby increasing the rate of the reaction.
Consider the following equation for the production of ammonia gas from hydrogen gas and nitrogen gas.
If the volume of the vessel containing hydrogen and nitrogen is decreased, the production of ammonia __________.
Since decreasing the volume of the container has the effect of increasing pressure, equilibrium is shifted to the right. An increase in pressure has the result of favoring the side of the reaction with fewer moles of gas. (According to the balanced equation, there are 4 moles on the reactant side as opposed to 2 moles on the product side).
Barium fluoride dissolves in solution according to the following equation.
Enough BaF2 is added to create a saturated liter of aqueous solution.
Suppose that 1M NaF is added to the solution, such that it does not change the volume of the solution. What would you expect to change as a result of the addition of NaF?
The pH of the solution will decrease.
The solubility product constant will decrease.
The solubility of BaF2 will decrease.
By adding NaF to the equation, 1M of F- ions are added to the solution. Thinking in terms of Le

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Retrieved Text: The latest reviewed version was checked on 13 September 2018. There are 3 pending changes awaiting review.
Use Sodium Nitroprusside. In the presence of sulphide ions a deep violet coloration is formed. [Fe(CN)5NOS]4- complex anion formed in the presence of sulphide ions is the cause for this coloration.colouration is important.
If a sulfide solution is reacted with silver nitrate, it forms a black precipitate of Ag2S.
When H2S is bubbled through a solution of Sodium sulphite or Sodium bisulphite, a white turbidity of sulfur is seen. What happens is, the S atom in sulphite/bisulphite (Oxidation state +4) and in H2S (Oxidation state -2) have coproportionated to give molecular sulfur in zero oxidation state. The reaction can be viewed as the reverse of a disproportionation reaction.
When H2S is bubbled through acidified KMnO4 solution, it decolorises and a white turbidity is observed. This is because, the powerful oxidizing agent permanganate ion has oxidized the sulfide ion (-2) to zero oxidation state. In doing so, the permanganate ions themselves reduce to Mn2+ ions, thus the purple/violet/pink color of the solution is diluted and eventually fades away as the manganous ions do not impart any color to the solution.
The nitrite ion gives several reactions based on its redox properties.
When it reacts with the I3- anion, the nitrite ion reduces itself to nitric oxide. The student should check the oxidation states of nitrogen in both the cases.
The yellow color of the I3- ions changes to a greenish tinge which later turns violet. This observation is made in the presence of an oxidizing agent which

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Retrieved Text: Roundup Xtend™ with VaporGrip® Technology is a glyphosate and dicamba pre-mix product with low volatility properties. XtendiMax® with VaporGrip® Technology has been developed and is a dicamba straight-good product with low volatility properties. In older dicamba formulations, dicamba ions (Dc-) are present in solution, combine with free hydrogen ions (H+) to form volatile dicamba acid (DCH). VaporGrip® Technology prevents dicamba ions (Dc-) from combining with hydrogen ions (H+), significantly reducing volatility.

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Retrieved Text: The atomic number of an atom is A. the number of protons in the atom.B. the number of neutrons in the atom.
C. the number of protons and electrons in the atom. D. the number of protons and neutrons in the atom. E. None of these choices are correct.
LO: 02.01.03 Relate atomic structure to the periodic table of the elements.
The smallest functional unit and associated structures of a living organism are A. atoms and their protons, neutrons and electrons.
B. molecules and their atoms, bonds and electrons. C. proteins and amino acids.
D. cells with nucleus, mitochondria and ER. E. water made of hydrogen and oxygen.
LO: 02.01.01 Describe the general structure of atoms and their constituent particles.
With an atomic mass of 16 and an atomic number of 8, it follows that oxygen __X__ has eight electrons.
__X__ can readily form bonds with 2 other atoms.
The nucleus of an atom is composed of A. protons.
D.protons and neutrons.E. protons and electrons.
The first, inner-most energy shell of an atom A. can have a maximum of 8 electrons.
B.can have a maximum of 2 electrons.C. is called the 2p orbital.
D. is called the 1s orbital and can have a maximum of 8 electrons. E. is called the 2p orbital and can have a maximum of 2 electrons.
LO: 02.01.02 Discuss the way electrons occupy electron shells that surround the nucleus.
Tritiated hydrogen (3H) differs from hydrogen (1H) in that A. 3H has 2 more protons than1H.
B. 3H has 2 more electrons than1H.C.3H has 2 more neutrons than1H.
D. 3H has the same number of neutrons as1H.
E. 3H has

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Retrieved Text: Definition, methods, meters: This page gives you an introduction to pH measurement and appropriate solution for your application.
The H+ is called hydrogen ion or proton, the OH- is the so-called hydroxide ion.
pH is the mathematical description of the activity of the hydrogen ions. It goes from about -1 to about + 15. Corresponding to this scale liquids are classified as acid, alkaline or neutral: If a solution is neither acid nor alkaline it is called neutral. This corresponds on the scale to pH 7. Acid means a high activity of hydrogen ions and pH lower than 7. Alkaline solutions are charaterized by a lower activity of the hydrogen ions respectively a higher activity of the hydroxide ions and a pH above 7. The grahic below illustrates with some examples the pH scale.
The pH scale is a logarithmic scale. The change of one unit means in fact a ten times increase or decrease of the activity of the hydrogen ions. This explains why the corrosiveness with increasing distance from the neutral point is strongly growing.
For determination or measurement of the pH it is necessary to have suitable equipment. This is provided by electro chemical measurement systems, litmus paper, indicators and photometers. Accurate results for pH are only provided by the electro chemical methods. The appropriate sensor is the pH electrode.
The pH electrode is an electrochemical sensor which consists of a measurement electrode and a reference electrode.The measurement electrode is made of a special glass which is due to its surface properties very sensitive for hydrogen ions. It

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Retrieved Text: Motara, Hasina (2011) Isothermal Titration Calorimetric Studies of Complexation Reactions. Doctoral thesis, University of Huddersfield.
The objective of this work has been to study the binding of metal ions to complex ligands expressing two or more metal binding sites, in terms of the thermodynamics of the binding events, and to use this information to contribute to the understanding of both the metal binding processes and the properties of the metal/ligand complexes. Two ligands have formed the basis of the study, one a naturally occurring enzyme and the other a newly synthesised ligand with two distinct binding sites (to form supramolecular complexes). The principle technique used to determine thermodynamic parameters has been isothermal titration calorimetry (ITC).
The first system studied involved the enzyme β-lactamase II from Bacillus cereus 569/H/9 (BcII). The binding of zinc (II), cobalt (II) and cadmium (II) was investigated in aqueous solution at pH’s from 5.2 to 7.2. By using three or more buffers at each pH it has been possible to determine not only the binding constants of the metal ions at these pH’s but also the molar enthalpies of binding (and hence molar entropies). In addition, the dissociation of hydrogen ions from the enzyme on metal binding was also observed. In the case of all three metal ions, one metal ion per enzyme appears to bind at low pH and two metal ions at high pH (within the pH 5.20-7.20 range). In the case of zinc and cobalt ions two metal ions seem to bind per mole of enzyme in a cooperative mechanism. In

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Retrieved Text: precipitation gold cyanide solution. precipitation of gold from aqua regia with sodium. extraction of gold for preparing ornaments. investing gold mining companies. gold mineral machine series kyf flotation tank in yantai. ... Prev: rock win mining machine for sale Next: crushing machine crusher fondant.
To make aqua regia solution you will need Hydrochloric Acid and Nitric Acid. These are sold separately from this kit. These are sold separately from this kit. This kit is a convenient way to obtain some of the chemicals used in scrap gold recovery.
Aqua regia is an extremely corrosive mixture of nitric acid and hydrochloric acid in the molar ratio of 1:3. Aqua Regia is a yellow - orange fuming liquid. It is used as an etchant, for some analytical chemistry procedures,and to refine gold.
Detailed Product Description: This kit provides the constituents necessary to create 500ml of. Aqua Regia. This is an extremely powerful oxidizing solution prepared from concentrated Nitric Acid (69% HNO 3) and concentrated Hydrochloric. Acid (38% HCL).
One of the safest and most advanced aqua regia gold refining systems available. The Shor Aqua Regia Gold & Platinum Refining System is ideally suited for refining of electronic scrap as well as jeweler’s polishing and bench sweeps.
Aqua Regia Definition. Aqua regia is a mixture of hydrochloric acid (HCl) and nitric acid (HNO 3) at a ratio of either 3:1 or 4:1.It is a reddish-orange or yellowish-orange fuming liquid. The term is a Latin phrase, meaning "king's water".
Hot sale Coconut shell activated carbon price for gold. Add to Compare .. Hot sale solvent recovery

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Retrieved Text: Removal of hardness from water is called softening. The softening is done by ion exchange process. The ion exchange process works on the replacement of the calcium and magnesium ions in the water by an equivalent number of sodium ions.
This eliminates the unwanted charasteristic of hard water because the sodium salt neither form scale nor a scum with soap but only lather.The resin will take up the calcium ion to the extent of what sodium ions resin will have with it.
Therefore, to give new sodium ions to the resins, the cheapest and the easiest mean would be to pass the solution of sodium-chloride (common-salt) through the resin. The same resin can be used over and over again to produce soft water a - periodic dossage of sodium chloride (common-salt) solution. So, recurring cost in such process is only the cost of common salt.
PURIC systems use the basic ion exchange principle. With this principle, ions in solution, including metallic cations such as calcium (Ca ++) and anions such as chloride (Cl -) are exchanged for other ions such as hydrogen ie. (H +) and hydrdxyl (OH-) that are contained inside synthetic ion exchange resins. By passing the solution through columns of cation and anion exchange resin, all the ions can be exchanged, leaving only hydrogen and hydroxyl, which combine, leaving pure water. Alternatively, by suitable choice of ion exchange resin, only a portion of the ions can be selectively removed.
When their exchange capacity has been exhausted,ion exchange resins can be regenerated.
Today, although the use of ion exchange

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Retrieved Text: All ion selective electrodes are similar in operation and use. They differ only in the process by which the ion to be measured moves across the membrane and by which other ions are kept away. Therefore electrode interferences must be discussed in terms of membrane materials.
Glass electrodes and solid-matrix/liquid-ion exchange electrodes both function by an exchange of mobile ions within the membrane, and ion exchange processes are not specific. Reactions occur among many ions with similar chemical properties, such as alkali metals, alkaline earths, or transition elements. Thus, a number of ions can produce a potential when an ion selective electrode is immersed in a solution. Even the pH glass electrode responds to sodium ions at a high pH (low hydrogen ion activity). Fortunately, an empirical relationship can predict electrode interferences, and a list of selectivity ratios for the interfering ions is available from the manufacturers' specifications or other chemical publications.
Solid-state matrix electrodes are made of crystalline materials. Interferences resulting from ions moving into the solid membrane are not expected. Interference usually occurs from a chemical reaction with the membrane. An interference with the silver-halide membranes (for chloride, bromide, iodide, and cyanide activity measurements) involves a reaction with an ion in the sample solution, such as sulfide, to form a more insoluble silver salt.
A true interference produces an electrode response that can be interpreted as a measure of the ion of interest. For example, the hydroxyl ion, OH", causes a response with the fluoride electrode at fluoride levels below 10 ppm. Also, the hydrogen ion, H+,

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Retrieved Text: 5.	What is a strong acid?
A: Strong acids are acids that undergoes complete ionization of hydrogen ions in water.
6.	What is a weak acid?
A: Weak acids are acids that undergoes partial ionization of hydroxide ions in water.
A: An indicator is a chemical substance added to determine the pH of a substance.
8.	What are the common indicators?
A: Universal indicator - Red at pH 1 for strong acids, Orange and yellow for weak acids, Green for neutral solution, blue for weak alkali and violet for strong alkali.
9.	What exactly is neutralization?
A: Process where acids and bases react with form salt and water only.
10.	What is a base?
A: A substance that reacts with acids to form salt and water. When it is soluble, it forms an alkali.
11.	What are the products when acids react with metals?
A: Salt and hydrogen gas.
12.	What are the products when acids react with metal carbonate?
A: Salt, water and carbon dioxide.
13.	What are the products when acids react with metal oxide, also known as a base?
14.	What are the products when acids react with metal hydroxide, also known as a base?
15.	What is produced when bases dissolved in water?
16.	Write the ionization equations of all common acids, including state symbols.
17.	Write the ionization equations of common alkalis, including state symbols.
A: NaOH --> Na+ + OH- or Ca(OH)2 --> Ca2+ + 2OH- or NH4OH --> NH4+ + OH- and again all state symbols are aq.
18.	Describe a simple test to prove that water is needed for the ionization of acids.
A: Dissolve nitric acid into water and ethanol separately. Connect a light bulb and a battery to the solution. The

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Retrieved Text: Envodil Mop* is a combination of Hydrogen Peroxide and Silver Nitrate with cleansing action used for cleaning, mopping and surface disinfection. Envodil Mop* is an effective, eco friendly and completely biodegradable solution.
Purified Water IP q. s.
Recommended Dilution: 10% solution (100ml Envodil Mop* and 900ml water) for mopping procedures.
Use 2 bucket system to get better results.

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Retrieved Text: Often referred to as the "Holy Grail" of energy storage, the economical and efficient conversion of water into hydrogen and oxygen with electricity (electrolysis) has been a goal of scientists for decades.
The amount of energy stored per kilogram of hydrogen is roughly two and a half times larger than natural gas and, most importantly, the only byproduct of burning hydrogen for energy is water. In the future, hydrogen could power everything from cars to buildings—but producing hydrogen from water on a global scale could put a strain on purified water sources that are needed for drinking, as well as many other industrial processes.
With this reality in mind, a team of chemists at Stanford University have developed a way to convert seawater, which makes up about 97 percent of water on Earth, into hydrogen. Findings are published in PNAS.
A typical electrolyzer consists of two metal electrodes—anode and cathode—that are immersed in an electrolyte solution and separated by a membrane. When electricity is passed through the solution, oxygen bubbles off the anode and hydrogen bubbles off the cathode. To minimize the amount of energy required to liberate the hydrogen from water, both electrodes are typically coated with a catalyst. The device developed by the Stanford team has many similarities to commercial electrolyzers—but with critical tweaks that allow it to use seawater instead of purified water.
As anyone who has been unfortunate enough to swallow a mouthful of seawater knows, it is salty. Salt, or sodium chloride if you remember high school chemistry, is composed of negatively charged chloride atoms

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Retrieved Text: Thus, as may be expected, chemistry is very relevant to the study of electricity.
and most of the rest is argon Ar, whose atoms don't combine.
Among the many chemical compounds. water has a unique role. On Earth, of course, it can be liquid, solid (ice) or gas (steam), and the existence of liquid water seems essential to life.
Although at first this seemed like a strange idea, today it is quite well understood. Many chemical molecules are formed when atoms share electrons, but molecules such as those of NaCl are different. There, the sodium atom (Na) gives up an electron to the chlorine (Cl), creating ions Na+ and Cl-, which in solid salt are held together by their electric attraction ("ionic bond"). Water, however, greatly weakens electric forces (on the atomic scale), allowing some ions to drift free whenever salt is dissolved in water, and allowing the water to conduct electricity.
The smallest atomic positive ion is the proton, the nucleus of hydrogen. Substances which when dissolved in water produce ions of hydrogen are known as acids and any such solution (e.g. HCl, H2SO4 ) has a sour taste. Of course, the fraction of acid molecules which actually breaks up into ions in a water solution can vary--it is large in "strong" acids and small in "weak" acids. Even in pure water a tiny fraction of the molecules is split up into ions H+ and (OH)– ("hydroxyl") at any time. The degree of "sourness" depends on the concentration of the acid in the water and on its strength; carbonated

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Retrieved Text: 2007-08-30 Assigned to BOC EDWARDS, INC. reassignment BOC EDWARDS, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: THE BOC GROUP, INC.
2008-03-18 Assigned to EDWARDS VACUUM, INC. reassignment EDWARDS VACUUM, INC. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: BOC EDWARDS, INC.
A process for fluoride removal from wastewater streams produced during industrial operation for further industrial use or to comply with environmental regulations. The process segregates the removal of fluoride and fluorosilicate ions, from the totality of ions in the waste water stream, thus improving treatment efficiency and reducing costs. Ion-exchange chromatography is used to remove the fluoride and fluorosilicate ions by passing the wastewater stream through one or more columns that contain a charged resin which selectively binds cations/anions in the stream. The fluoride ions are washed from the column and then collected for removal or use in other processes.
Many industrial operations utilize fluoride, often as hydrofluoric acid or as fluoride salts such as ammonium fluoride. For example, alumina and silica etching, cleaning, etc. and semiconductor production utilize large amounts of hydrofluoric acid, and other fluoride compounds. As a regulated element in water discharge, for reasons well known in the art, the wastewater generated needs to be processed for fluoride ion removal. Additionally, when using hydrofluoric acid (HF), semiconductor manufacturers often require an ultra-pure hydrofluoric acid.
The typical semiconductor manufacturer may produce an average of 10,000 gallons per day of mixed acidic fluoride waste. The production of such vast quantities of fluoride ion waste, however, presents significant disposal problems. Fluoride wastes are becoming subject to

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Retrieved Text: During charging in the new battery, manganese ions (red) from the manganese sulfate electrolyte solution deposit on the carbon-fiber-based fabric (green) at the cathode while the platinum catalyst (yellow) at the anode fabric (purple) produces hydrogen gas from water. The process is reversed during discharge.
A new battery made of manganese and hydrogen could be easily scaled up to store energy for the grid, researchers say. The battery houses a large amount of energy, lasts a long time, and could be inexpensive enough for the job.
Most current battery technologies fall short in at least one area. Lithium-ion batteries that power laptops and electric cars have energy densities of over 200 Wh/kg, but they cost more than twice the DOE requirements. Redox-flow batteries are also expensive. Meanwhile, lead-acid batteries are cheap, but they last only 500 cycles and their energy densities are subpar. Researchers have recently made low-cost batteries with aqueous solutions of zinc and sodium ions as electrolytes, but they also suffer from low energy density and short cycle life.
A prototype manganese-hydrogen battery cell (photo, right) consists of a cathode (green) inside of a steel cylinder and a small anode (purple) in the middle, with the space in between filled with electrolyte.
Cui’s group turned to plentiful manganese. He says the new battery meets all the critical needs for the grid. It has the potential to be low cost because manganese and hydrogen are abundant. It has an energy density of around 140 Wh/kg, thrice that of lead-acid. And it boasts a very long life of more than

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Retrieved Text: I will tell you right now, a homemade chlorine battery is not going to be as cost effective as commercial batteries. In the nanny state it is almost impossible to get pure enough chemicals to really experiment. However, I think it is important for the sustainable power types to understand what is going on within their system. This allows them to make informed decisions when they buy their batteries.
In a true grid down collapse, i.e. Mad Max scenario, the ability to make batteries from scrounged materials may come in handy. Now before you get too excited, if you get one volt per battery cell you are doing extremely well.
It will take many of these cells to get any usable energy. This is not a cost effective way to power your home.
In the video we make a battery using a mason jar, copper, aluminum, and chlorine bleach.
Basically, any two different kinds of metal can be placed in a conducting solution and you get a battery. In some schools they still teach an experiment that involves inserting copper and zinc strips into a lemon or a potato to make a battery.
Once you get the basic chemistry down, feel free to experiment. I have seen instructions for making large cells from aluminum soda cans riveted together and inserted into long PVC pipes. Right now I am experimenting with PVC pipe, grounding rod, and aluminum pipe.
If you want to see the procedure to make a chlorine battery, please watch the video.
As promised in the video, this article will discuss the

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Retrieved Text: In this chapter of Redox Reaction, you will be learning what precisely the term ‘redox’ means. This topic is short, but a significant one because it is the foundation of more challenging topics later on. A clear understanding of this topic is needed to understand reaction mechanisms for future topics in O and A Levels.
The term ‘redox’ is used to describe any type of chemical reactions. We can characterise any chemical reactions into two main groups: redox reaction and non-redox reaction.
Redox reaction is a chemical reaction where reduction and oxidation have occurred.
On the other hand, a non-redox reaction is where neither reduction or oxidation have occurred.
Important note: If a chemical reaction is a redox reaction, both oxidation and reduction must co-occur. In other words, whenever reduction occurs, oxidation must also occur in a same chemical reaction.
When both reduction and oxidation happens, we describe the overall reaction as a redox reaction.
Reduction and oxidation are key terms in this chapter. So what exactly is the meaning of reduction and oxidation?
(4) Experience an increase in oxidation state.
In the previous statement, ‘species’ can mean any chemical ions, atoms or compounds. Anyone of the four requirements would indicate an oxidation reaction.
When a species gains oxygen, it is said to be oxidised. For example, when zinc reacts with atmospheric oxygen to form zinc oxide, zinc is oxidised to form zinc(II) ions, and we say that oxidation occurs.
Carbon gained oxygen and is oxidised.
Aluminium gained oxygen and is oxidised.
Oxidation is also said to happen when a species loses hydrogen. For instance, when hydrogen sulfide

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Retrieved Text: I ammonia an ion when it is dissolved in water?
The anoxic layer also contains high concentrations of ammonia and phosphate. These chemicals are almost completely absent from the upper layer.
1. Is it technically correct to call ammonia (NH3?) an ion when it is dissolved in water. I understand that salt (NaCl) disassociates when dissolved in water. Does ammonia do something similar?
2. If ammonia did disassociate in water what does it disassociate into?
3. Does dissolution in water generally involve some kind of disassociation? Would the disassociated components generally be called ions? For instance does glucose disassociate when dissolved in water or for the most part are there just complete glucose molecules floating in water in a glucose solution.
I have more questions but for the most part I don't know enough to ask good questions on this. I am really looking for just a little general information about the nature of solutes and in particular how should the sentences in the Jellyfish Lake article linked to above be worded to be correct.
It is incorrect to call ammonia an ion. It is a molecule.
Ammonia does not dissociate, but it does ionize in solution to a small degree. NH3 + H2O <-> NH4+ + OH-. The degree depends on conditions, but is unlikely to be above 5%.
Only for ionic compounds (and acids). Glucose and ammonia are neither.
Thanks for the response. Could you confirm that I understand all this correctly?
1. Only a small percentage of the ammonia dissolved in water turns into ions so the use of the term "ammonia ions"

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Retrieved Text: Resistors in series R = R1+R2+R3+R4….
Rank Hydrogen, Covalent and Ionic by strength (strong, weak, very weak) Covalent – Strong. Ionic – Weak. Hydrogen – Very Weak.
Hydrogen Bonds Weak electrical attractions. Takes place between the ends of molecules and H. (ex. holds water molec. together in solution).
Lipids C,H,O present, but much less O than either, C to H ratio 1:2. example is lauric acid (C12, H24, O2), fats, oils, waxes.
Buffer Removes or replaces hydrogen ions in solution. Buffers maintain the PH within normal limits.
Proteoglycans (carb-protein combination) large polysaccharides linked by peptide chains. Important thickening agent for tissue fluids.

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Retrieved Text: The electrolysis of water yields oxygen and hydrogen gases and simple calculations estimate the charge of the ions.
Do not ignite the hydrogen gas directly in the burettes but sample it as described below.
0.4 M sulfuric acid is not hazardous.
The Worcester voltameter kit consists of two 250-ml burettes mounted vertically so that they will fit inside a tall gas jar (see diagram). The electrodes consist of stiff wires covered with plastic insulation except where they are within the inverted burettes. Ideally, these tips are plated with platinum. The advantage of this design (which many schools have) is that the glass items are standard and easily replaced when broken.
The Hofmann voltameter is an alternative piece of apparatus. It is expensive and easily broken, but many schools have one. There is also a mini-version consisting of two small test-tubes in a small trough.
Although this is traditionally described as 'electrolysis of water', showing that an electric current can split water into two volumes of hydrogen to one of oxygen, it is a little more complicated. Pure water contains few ions so the process is very slow. To obtain results in a reasonable time, sulfuric acid or another electrolyte is added. See the CLEAPSS Laboratory Handbook (section 11) for a fuller discussion (in colour on the CD). For the oxygen problem, see teaching note 2.
In this context, the object is to indicate that each hydrogen ion is associated with only half the electric charge associated with each copper ion in the electrolysis of copper.
a The circuit is connected as shown.
b Only

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Retrieved Text: Detection of heavy metals via fluorescence has attracted increasing attention. Herein, we report a novel copper(II) ion (Cu2+) sensor using fluorescent polydopamine (FPDA). Dopamine is easily oxidized to polydopamine by oxygen in alkaline solution, and oxidized polydopamine does not fluoresce. However, under a nitrogen atmosphere, FPDA can be produced by adding hydrogen peroxide into a dopamine solution in the presence of Cu2+ ions. The fluorescence intensity of FPDA is strongly dependent on the concentration of Cu2+ ions. At higher concentrations of Cu2+ ions, the photoluminescence intensity of FPDA also increases at a higher rate. FPDA exhibited a highly sensitive and selective response to Cu2+ ions over other ionic competitors in the biological milieu, achieving a detection limit as low as 1 nmol L-1 (nM). This study shows that the method can be used for monitoring in vivo Cu2+ ions owing to the distinct properties of FPDA such as strong fluorescence signal and biocompatibility.

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Input Text: Read the passage below and choose the right answer to the following question (choices are Tony's or Ian's ):

The higher the crests of a wave are, the greater the amplitude.


Ian surfed a 6 foot wave. Tony surfed a 10 foot wave. The wave with the lowest amplitude was Tony's or Ian's?

Target Text: Ian's

#### Retrieved Documents ####

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Retrieved Text: What is there left to do after you break a world record, except break it again? Hawaiian surfer Garrett McNamara, who in 2011 rode a 78-foot swell to claim the record for largest wave surfed, may have broken the record a second time. McNamara traveled to the coast near Nazare, Portugal, where he caught a wave reported to be around 100 feet.
The claim, however, has yet to be verified. Measuring a wave’s precise height is quite difficult and the only evidence is strictly visual. McNamara’s record-breaking 2011 wave, also in Nazare, became a source of controversy when it was originally estimated to be about 90 feet. It was brought down to 78 feet upon closer inspection, just one foot higher than that surfed by the previous record holder, Mike Parson.

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Retrieved Text: Lampung or many people says “Southern Sumatra” has many surfing location. Some place are very well-known by International Surfer.
This wave is an 800 meter long lefthander that wraps around the point and provides some great barrels and carving sections. It is really consistent and caters to surfers from the beginner to advanced. This wave can be ridden from 3 to 10 feet and is walking distance from the camp.
This wave is punchy, peaky beach break that turn on when everywhere else is flat. Expect lot of peaks and the opportunity to surf without your booties. 2-6 foot and fun.
This wave is a perfect short rampy tube ride. Best when the swell is massive everywhere else. Holds a flawless 2-4 ft. Really fun wave suitable for beginner to advance.
A really solid right hander that as great barrel section and some really challenging sections for manuveres. Holds from 3-8 foot and is a really long fun ride.
Mainly a wave for bodyboarders, a very sucky and steep, left barrel that is quick and heavy. Holds 3-8 foot and is for the experienced surfer and bodyboarder only.
A fantastic, heavy and brutal waves. Best surf on high tide when there is a lot of sweel. Book a driver or ride a motorbike for 2 hours to get there. It s a very deep barrel that holds 4-12 foot and is for the experienced surfer only. The end section is so scary it should only be surfed on high tide. Also has a left hander for the adventurous.
*all data based on the

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Retrieved Text: Big wave rider Mark Visser has entered the History of Surfing. The pro surfer has surfed 30-40 foot waves in a night ride off the shore of Maui, Hawaii. It's not the apocalypse, it's surfing breaking its own frontiers.
The 28-year old Australian used a special surfboard with built-in LED lights, engineered by NASA for submarine lighting. The red light ensured that the helicopters and jet skiers were able to spot where Visser was riding each wave.
This is the first time a surfer tries to ride big waves in the dark. Mark prepared this project for two years. "It is the most exciting thing I have ever done. It wasn't until I saw the pictures I realized how big it was," said the intrepid surfer.
Mark has hit the waters at 2am, in complete gloomy conditions. Watch how he surfed his night waves. It looks like he's a surfer from the future, with jet-powered fins. How crazy is that?
Riding huge black waves isn't easy and Visser got the helping hand of the tow-in jet skis. "Riding in complete darkness meant I had to go off feeling. I had to zone out from how you normally ride and just be part of the wave. I am so pumped to achieve something that no one thought possible and that I was told that it couldn't be done."
Mark Visser is planning a full-length documentary named "The Night Rider," to be broadcasted late 2011, early 2012. In the past, Visser is known for riding big waves and placing in the Top 10

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Retrieved Text: Action starts with Professional Big Wave Surfer Toby Cunningham getting towed into a massive wave in Nazaré, Portugal, during the big wave session of February 7, 2019, which was one of the biggest days of this Winter season in Praia do Norte.
After successfully riding the huge wave, which was the first wave of a big set, Toby gets caught by the white water and falls off his surfboard. By then Toby was further in the inside, which is the most dangerous spot in Praia do Norte, also known as the impact zone. His rescue teammate, Surfer Glyn Ovens tries to reach him with the Jet Ski, but there’s little opportunity for a pick up since the next wave was already too close. Toby takes the first impact of a giant mass of white water, and as he resurfaces Glyn was already getting close with the jet ski to attempt another rescue, but Toby sees another huge wave rolling in and signals Glyn to abort the pickup, taking that second enormous impact on the head. The moments that follow were of great stress, and little window of opportunity for a successful rescue, Toby’s 25 years of Big Wave experience is put to the test, he manages to stay calm under pressure and eventually gets picked up by Brazilian Surfer Ian Cosenza that came in to help with the rescue.
Besides Surfing Big Waves, Toby’s other passions involve Global Finance and Crypto Currencies (he helps running “Crypto Tips” Channel on Youtube), he does volunteering in India at the Mother

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Retrieved Text: McNamara (in 2013 in Nazaré) still surfs its monster waves, despite the risks. Last year, a fall broke champion British surfer Andrew Cotton's back.
... wave off Portugal has produced a world record for a Brazilian surfer. The World Surf League says Rodrigo Koxa has ridden the biggest wave ever surfed.
Biggest wave ever surfed: Rodrigo Koxa's record ride!
April 30, 2018 8:21am EDT April 30, 2018 8:21am EDT A Brazilian surfer now holds the Guinness World Record for the biggest wave ever surfed.
In extreme sport, the world record of the biggest wave ever surfed has just been officially defeated announced Sunday, April 29, the World Surf League.
Evan Kirstel on Twitter: "🌊 🏄 Dude! > #Brazil's Rodrigo Koxa sets record for biggest wave ever surfed #SundayMorning #surfer https://t.co/5FA5rt31S7"
Nazaré causes confusion: Who surfs the biggest wave in the world?
Brazilian surfer Rodrigo Koxa set a new Guinness World Record for riding the biggest wave ever surfed, an 80-footer in Nazaré, Portugal.
Watch Brazilian surfer Rodrigo Koxa break the world record for the largest wave ever surfed.
The world record for largest wave ever surfed now belongs to Brazilian surfer Rodrigo Koxa. Watch his historic run.

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Retrieved Text: After a week of forecasting, planning and preparation, Team WRSC scored one of the most memorable days of the year at the famous, Ollie’s Point. With not a drop of water out of place, Team WRSC surfed machine-like 4-6ft right-hand barrels for over 6 hours! The waves never seemed to stop, and with over 500 waves ridden throughout the day, we concluded our journey with noodle-arms, salty skin, and smiles from ear to ear.
Chief Operating Officer, Pat McNulty grabbing the first wave of the day and showcasing his classic style with over 50 years of surfing experience.
Even the birds were getting tubed!
Reservations Julie putting on a show for the boys.
Drag your hand and pull in!
Strong emotions after 3 tubes on 1 wave!
Julie dropping in and waiting for the wave to open up.
When Joe Walsh claims this was one of the best days he’s surfed Ollie’s in the past 15 years, we all felt very humbled. Here’s the legend himself setting up for the tube!
Sets out the back!! More style with Niki.
Pat setting up for the tube. The waves this day barreled perfectly from the point all the way to the beach. 45 seconds of regular foot perfection.
Brian racing the inside tube section!
Enjoying a refreshing Witch’s Rock Pale Ale after a long day of surf.
This is how it goes. Niki makes the beer, Joe drinks the beer.
Ending the day with cold beer and smiles from ear to ear.
Big thanks to Shaka Media for the photos and WRSC for an amazing group with positive vibes. We will be

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Retrieved Text: It’s no surprise surfers have a natural affinity for the ocean and it’s waves. However, select surfers have the bold and daring nerves to conquer some of the largest swells in the ocean. Although measuring the exact height of a wave is challenging, most waves are larger than they appear. Thanks to YouTube these surfing swell videos have gone viral, and are a source of inspiration for future surfers to overcome fear and conquer the wave of their dreams.
Check out some of the original surfers to conquer some of the largest surf. Names like Eddie Aikau and Greg Noll make waves for future surfers. The Quicksilver Big Wave is named in honor of Aikau, who lost his life at sea in 1978. Noll became famous in 1957 for surfing giant swells known as the Pipeline in the Wiamea.
Laird Hamilton takes on the giant waves filled with mass, power and velocity. What seems like a death-defying stunt comes out with a possible belief that conquering something imaginable is possible even in the ocean. This break in Tahiti is known as one of the most dangerous wave in the world.
Shane Dorian and Mark Healey paddle the waves at Waimea Bay for some after storm swells. With the crowd surfing and a giant black wall of water, these two lucky surfers successfully caught this monster.
Explore some massive swells from the 2009 Billabong XXL event. The four minutes of footage is nonstop riveting action in Maui. From successes to wipeouts, these are the bset of 2009 Jaws.
Surfer Ken Bradshaw chats

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Retrieved Text: How Big Was the Biggest Wave Ever Surfed?
As of January 2013, Garrett McNamara, has surfed the biggest wave ever recorded surfed at 100 feet!
Garrett McNamara beat his record of the biggest wave surfed from 78 ft in November 2011.
Shawn Dollar holds the record for current paddle-in at 61 ft from May 2013.
The highest motorcycle jump is held by Robbie Maddison at 35 ft in January 2009.
The highest snowboard air on superpipe is 23 ft by Shaun White in January 2010.
And last, but definitely not least, the highest outdoor high jump at 8 ft by Javier Sotomayor on July 1993.
Fill out the form below to download the full size infographic.

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Retrieved Text: “Um, I reckon we should get out there yay”.
Two weeks of Mentawai perfection on board The D’Bora.
Two weeks of Mentawai perfection on board The D’Bora was scored in Early August by a mixed crew from Angourie/Yamba plus a couple from the Goldy.
Tracks caught up with Blakey Wolfe, a 30-year-old surfer from Angourie and got his take on the trip.
We surfed everyday! Our first seven days couldn't have been better with 4-8ft epic waves the whole time. Our last four days we had fun waves around 3-5ft.
We were lucky enough to have two solid swells, the first swell was from the west which is when we scored HT's and the next was from the south. We were lucky with the wind. It was light and variable most of the time. I heard August normally has stronger winds.
We had one epic whole day at HT's, 6-8ft no wind all day.
HT's, Roxy’s, Macca’s, Lances Left. We surfed Greenbush on the wrong swell direction so it was closing out at the end, would love to surf it perfect.
Ha ha, this wave took me most of the first day to figure out. It's a lot heavier and shiftier than I thought it would be, especially at 6-8 foot. On a 6ft+ set you kinda get a roll in take off but not a real easy one, then you want to just set up for the barrel section and once your in, you really need to pump through the barrel to make sure you get out and avoid the 'Surgeons Table' (the

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Retrieved Text: One of the primary reasons for travelling around Australia was for Dean to surf as many beaches as possible. The following is what he had to say about the waves he found.
Just north of Margaret River you come to Yallingup – a nice quiet little sea-side town. We were there for just over a week and, although the surf had dropped back, there was a few waves to be ridden.
Yallingup reef is a very nice left hand break and I did manage to get a few 3 to 4 foot waves that provided a good 150 metre ride.
I was just a little disappointed that it didn’t really turn on while I was there. Another great spot for a surf all the same.
What can I say about this great Aussie surf destination – WOW I can now say I have surfed this iconic wave.
Spent five days here but when we first arrived it was only small – 2 to 3 foot and that was fun, but over night the swell rolled in and the sets were up to 8 feet. Now to me that’s pretty big.
I did managed to catch a few and it did get the adrenalin flowing, but alas on my last day, I snapped my board when I had to bail off it to dive under a breaking wave. Rather my board than my back. And I wasn’t the only one, I saw a few get snapped while I was there, but it was definitely worth it.
Make sure you get to this spot –

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Score: 62.37262
Retrieved Text: Hound of the sea – that’s the name of the book about Garrett McNamara, legendary big wave surfer who’s surfed the biggest wave that most certainly has ever been surfed. Follow Garrett to Lofoten, Norway, and get to know the man inside the wet suit.
Garrett has been a friend of Thule since many years back and he’s a great inspiration to many people around the world. But more importantly, he uses his success and fame to inspire and teach the young generations powerful and important lessons of life. Garrett believes that we must encourage our children to follow their dreams. And we must take care of the environment. Otherwise there will be no ocean to play in, no snow to ski on and there will be no woods to run in. The world was lent to us by our parents, it’s up to us to be responsible and to leave a healthy environment for our children!
Garrett GMAC McNamara is the legendary big wave surfer who’s still holding the Guinness World record of biggest wave ever surfed, in Nazaré 2011.

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Rank: 11
Score: 60.48039
Retrieved Text: With a warm smile, Emily Erickson will invite you to go surfing with her. And you will nervously ask: Uh, where?
Erickson’s introduction to surfing began at Sunset Beach on Oahu’s North Shore, which some would argue is like starting your climbing career on Mount Everest.“Because my dad surfed there, I never thought it was impossible,” she says. “There were no limits.
As a child in Hawaii, Erickson watched her father, Roger, a big-wave legend and former North Shore lifeguard, ride giant swells while she played in the sand. At 17, she began learning about the ocean and its moods on a boogie board. A year later, her father gave her his 10’6″ big-wave gun. Erickson was hooked. “Nothing hit me as hard as surfing did,” she says.
Erickson never expected to grace the cover of The Surfer’s Journal or get nominated for two Billabong XXL awards. Still, finding sponsors is a struggle many female big-wave athletes face. Among other projects, Erickson waits tables at a sushi restaurant to make ends meet. But she has found a different kind of richness in the sport. “On big waves especially, I have this hyperaware, instinctual experience that makes me incredibly high and so happy,” she says.
At last year’s first WSL women’s big-wave competition at Jaws, on Maui’s north shore, Erickson saw a wave she thought could be a winner. As she rocketed down the nearly 40-foot face, the wind flipped her board sideways and spun her upside down. She tore her ACL, MCL, quad, and calf muscle.

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Rank: 12
Score: 60.45395
Retrieved Text: Two years ago, when John Florence won The Eddie, the buoy readings were 20 feet at 16 seconds, and the biggest sets were closing out the channel at Waimea Bay. It was so heavy that, after the contest ended, only a few guys braved a freesurf.
North Carolina’s Mason Barnes, a soft spoken, 24-year-old under-the-radar big wave guy, was one of them.
In the years since, we’ve seen photos of Barnes popping up at all the premiere big-wave spots around the world: Jaws, Puerto, Mavs, Cortes Bank, and… Tres Palmas?
Tres Palmas, in northwest Puerto Rico, is known to produce big waves during large winter swells. But thanks to winter storm Riley and its once-in-a-decade buoy readings (20 feet @ 16 seconds just off the coast of PR), Tres went XXL, and Barnes, along with a small crew of fellow east coasters, was there to experience an Eddie sized swell close to home.
We gave Barnes a ring to hear about his experience.
How you feeling after these last couple of days?
Good! But I’m so fried. So sunburnt. I just got in from the water 10 minutes ago. It was a pretty awesome day over here.
20 feet at 16 seconds happens once in a decade in the Caribbean. If that. What were your first thoughts when you saw this swell forecast?
I had no idea what to expect. I knew the numbers were there, but you still never know if it’s actually gonna translate in the Caribbean. I got here super early Sunday morning, and I was so blown away by how

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Rank: 13
Score: 60.08605
Retrieved Text: Perfect, barreling right-hander from the BSR Surf Ranch in Waco, TX.
While the world has been laser-focused on Kelly's Wave -- aka Surf Ranch by Kelly Slater Wave Co. in Lemoore, CA -- a sleeping giant has been in the background creating arguably better, more perfect waves. Enter into the equation American Wave Machines (AWM), a Solana Beach, CA, company that has their own unique approach to creating the perfect wave for surfing.
BSR Cable Park and American Wave Machines teamed up to build a one-of-a-kind wave pool in Waco, Texas. The BSR Surf Resort debuts the Perfect Swell technology, and will create all types of waves with short intervals between them. The size of the waves will vary between 3 and 8 foot.
Historically, surfing has been limited to coastal destinations with bodies of water in front of them. AWM aims to take surfing, the world's most aspirational sport, inland to populations that may not have beach access.
Inspired by footage of Oahu's Waimea river blown out, flowing and being surfed by locals...AWM began research and development on the world's first artificial standing wave, SurfStream®. Testing started with a 1/12th scale model in founder Bruce McFarland's backyard. Then, in 2004, the first rideable prototype was installed into shipping containers and tested by local New Jersey surfers. Since then, incremental improvements of the technology and a growing interest in surfing outside of the ocean has led to the opening of more than a dozen SurfStream® surf parks worldwide.
With Surfing making its premier appearance at the 2020 Olympic Games in Tokyo,

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Rank: 14
Score: 59.881683
Retrieved Text: Charlie had a big decision to make. He and his friend Javier were being offered professional surfing contracts with Rip Curl Men. Charlie and Javi were of course happy, but they also didn’t know if they wanted this life. Surfing was a dangerous sport, and if they accepted the contract they would be surfing pipeline all day everyday. Pipeline was the third most dangerous wave to surf, next to 100 foot-waves and Mavericks.
Charlie was really taking this into consideration. He had a family to worry about. He knew his wife wasn’t that happy that he was a big time surfer because her father had died surfing pipeline. Javier was not as good of a surfer as Charlie , but he wasn’t a very popular one. Charlie had made millions of dollars but Javi only made a few thousand.
Charlie called Javier around 4:30 am. “Hey man, they got a major swell coming in in about twenty five minutes. If you’re interested I’ll be at Waikiki Beach.” Charlie headed up to the beach, and what he saw was one of the prettiest sights he had ever seen. The waves were bigger than he expected, they were rising to at the least 39 feet. These were Mavericks. Charlie knew Javi wasn’t trained to surf these big of waves. Charlie and Javier paddled out, it was rougher than it looked. Charlie could see a big time wave in the back, he waited a few seconds until the wave grew closer. He started to paddle as fast as he could, and

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Rank: 15
Score: 59.72121
Retrieved Text: Rarely surfed, some okes paddle out here when factory is too crowded. The wave breaks a shallow flat ledge.
English (Traduzir este texto em Português): Rarely surfed, some okes paddle out here when factory is too crowded. The wave breaks a shallow flat ledge.
Best left for the pros.
English (Traduzir este texto em Português): Best left for the pros.

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Rank: 16
Score: 58.60845
Retrieved Text: Brazilian pro-surfer, Rodrigo Koxa recently became another record-holder. He officially broke the record of the largest wave ever surfed at the Nazare Beach in Portugal and received a Guiness World Record on the 30th of April. The surf was actually made last year on November the 7th, which was made official at World Surf League’s Big Wave Awards, where he also accepted the Quiksilver XXL Biggest Wave Award for biggest wave of the year. The height of the wave was a massive 80 feet (or 24.5 meters).

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Rank: 17
Score: 58.49165
Retrieved Text: For two years running, or padding, Nazaré, Portugal has dominated surf headlines. There the world record sized waves have been successfully surfed, mountainous waves that crash into huge rocks on razor sharp coastal cliffs. I’ve seen it, it’s pretty damn scary, I wouldn’t do it.
Longer rides have been surfed and documented. Pororoca in the Amazon’s tidal bore; 45 minutes on one muddy wave in a very remote jungle. Robby Nash cruised for 3.03 minutes on a nice wave off a beach somewhere in the Pacific, he had a paddle. Winter in Lagos may not be the high tourist season, unless you travel with a wet suit and your car has a roof rack. I’m still wondering how Alex Botelho, after his 1 minute and 40 second record breaking ride, got back to where he started. Unlike the Nazaré surfers who bravely face breaking the latest record, Alex didn’t plan this, there wasn’t a massive support team ready to whisk him to the media tent, then to his deluxe suite somewhere. Alex was just having fun.
This entry was posted in ex-pat in lagos, Ex-Pats Abroad, Lagos, Lagos Portugal friends, Lagos Pt history, Portugal, Surfing, Travel and tagged Alex Botelho, Duke Kahanamoku, longest wave surfed in Portuga, Surf Lagos Portugal. Bookmark the permalink.
Awesome. I would have given him a free ride.
It’s actually a cool and useful piece of info. I am satisfied that you shared this helpful info with us. Please keep us up to date like this. Thank you for sharing.

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Rank: 18
Score: 58.36228
Retrieved Text: A 10-year-old surfer surfed with a great white shark.
Eden Hasson was catching his last wave, while surfing at Samurai Beach in NSW Tuesday evening.
← Donna West IS our Working Woman!

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Rank: 19
Score: 58.341114
Retrieved Text: A 14-strong team has surfed into the world record books by riding a wave on a single giant surfboard in Cornwall. The record bid was held at St Ives, on a 37-feet board weighing 400lb.
On their fourth attempt the team of 12 men and two women stood up and surfed into shore together, setting the first official world record for the most people riding a single board. The team included the cream of British surfers, as well as an Australian and three South Africans. Britain's surf champion Alan Stokes, 22, said riding the two feet wave with his team was not easy.
The fibreglass board - officially the longest in the world - set an unofficial record when it was first used by a team of 12 people at its launch in Cornwall in 1999. A New Zealand team went one better and managed to get 13 people riding a wave on one board.
The giant longboard was created by team member Tim Mellors at Custard Point boards in Newquay. It will now go back on display at the town's Longboard House shop.

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Rank: 20
Score: 58.314022
Retrieved Text: Best for: People who have a little experience on a surfboard and can paddle and catch a wave by themselves to surfers who are just getting familiar with a short board. Also fine for complete beginners if accompanied by an instructor/guide.
Crowd factor: medium - high. Gets very crowded at times, one of the most popular spots especially when the conditions are good. Due to this being a beautiful spot to teach lessons and the soft, easy nature of the wave, Daku is a favorite wave for many resorts to take their guests.
How to get there: You can find boats for hire by the market / boardwalk in General Luna. It takes about 15 minutes each way and the driver will wait for you (or surf with you) and take you back for 200 pesos per person (min 2 pax).
Kind of wave: Daku is best surfed at about shoulder high and with light, offshore (west) winds. When these conditions line-up Daku is one of the best waves in the world to surf. Slow, soft take-off onto a decent sized right-hand wave that goes on forever in the most beautiful scenery you've ever seen. These conditions are most often seen in the peak season of late Aug to November.
Daku can be surfed any time of the year that the winds are light or off-shore and there's a decent sized swell. It doesn't work too well through the winter (choppy because of on-shore or cross-shore winds) and it's usually flat in the summer months. Ideal conditions are most often

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Rank: 21
Score: 58.161774
Retrieved Text: Nazaré, Portugal is home to some of the biggest, most exciting waves on the planet, making it ideal for the big-wave surfing community. With swells the size of skyscrapers, this location brings together surfers from all over the world, each trying to catch their own monster ride.
On November 10, 2011, Garrett McNamara did just that, surfing what was then considered the tallest wave ever ridden. And to everyone’s enjoyment, the 44-year-old Hawaii pro surfer filmed the entire event on video.
This week, after a panel of big wave and photography experts analyzed the footage, Guinness World Records officially certified McNamara’s wave as the ‘Largest Wave Ever Surfed’ at 78 feet.
It may not stand for long, though—check out this video of him surfing a 100-footer in 2013, which still has yet to be certified by Guinness World Records.

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Rank: 22
Score: 58.09685
Retrieved Text: I went to short sands mid-morning on Friday, July 1st. Overnight and in the early morning the winds were light and the surf forecast was 6-8 foot (which is huge), medium period, semi-glassy in AM moving towards junky in the PM as winds picked up. The tide was low right about 8:30 which meant that it was difficult to take advantage of the best wind/surf combination of the day. But I went anyway, surfing from about 10:30 am to about 12:00 pm, on the first half of the rising tide.
Round these parts surf conditions cannot approach ideal unless you have a rising mid-to-high tide coinciding with the morning’s low and/or the afternoon’s offshore winds, combined with a significant wave with low period (4+ feet, 10+ seconds).
The forecast had me thinking that Friday would the first day where I could even get close to this kind of situation. But it turns out it was far from ideal.
The winds were a strong NW (oriented like N given the angle of Short Sand beach), and way higher than forecast for the late morning. They screwed everything up. Plus, the waves were junky and complicated by a multiple cross swell and local wind waves. And moreover, not having surfed for six months, it felt like nothing was working right for me.
My huge and heavy single-fin 9′ 6″ Bruce Grant Super Ugly board was a liability rather than any kind of aid in the pounding beach break. Once I got outside the break zone, the southbound current caused by the 10+

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Rank: 23
Score: 57.930305
Retrieved Text: The Maldives has the coolest airport I have ever been to!
On its own island and only 20 meters from the airport exit, there is a huge wharf with taxi boats (Dhonies) that take us to the Cobia surf charter boat which is a very rad experience.
We surfed head high waves down south at Tucky Joes, Quarters, Rip Tides, Jailbreaks and Sultans.
We then surfed our way up north, finishing up at pumping 6 foot+ Cokes and Chickens.
The waves are generally softer than what I am used to in Indonesia.
11-13 second period swells in the Maldives compared to 15-22 second period in Indonesia.
Still big and powerful, but not as round or as much variety as in the Mentawais, but the Maldivian reefs will still give you a beating if you get caught out.
The Maldives are perfect for intermediate surfers, and caters well to family groups.
There are a couple of heavy barreling waves like Tucky Joes and Cokes, but they need a few different variables to come together to pump, so it can be a bit hit and miss.
There was no shortage of swell in July, in fact most of us were under gunned with our board selection.
We had many overhead days. Don’t get caught out like us! The currents are strong during spring tides, the extra foam and couple extra inches makes everything more fun.
We had a great trip, fun times and plenty of waves in a very beautiful part of the world.
Thanks to Trevor, The Perfect Wave and Cobia surf charter for an unforgettable experience.

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Rank: 24
Score: 57.742096
Retrieved Text: Some TGSA U18 members recently participated in the Surfing America Prime Series event at Steamer Lane in Santa Cruz, CA. It was a great opportunity extended to TGSA by Surfing America. Board member Rob Henson worked to put this opportunity together for some of our top competitors and we asked him to give us a summary of the trip. Thank you Rob for your hard work and thank you Greg Cruse and Surfing America for welcoming the Texas kids and your hospitality during the trip.
The Surfing America Prime Series took over Steamer Lane in Santa Cruz, CA January 10th and 11th. The TGSA was invited to bring some of our top surfers out the the contest as well as participate in a “mock” heat on Friday January 9th. Tyler Bacquet, Nathan Marney, Kelly Scroggs, Ian Appling, Aransas Blaha and Maddie Garlough arrived in Santa Cruz on Tuesday Jan 6th and immediately took to the water. Although the surf was fairly small the first few days, we were greeted with 4-6 feet surf on Friday which slowly faded on Sunday. The biggest concern for the groms was getting used to taking off at the “SLOT” which is right next to the cliff. I was really proud of the way they adapted to the conditions and became comfortable with the break. On Friday, Tyler Bacquet was placed into a mock heat with current USA Surf Team members and definitely caught the attention of the west coasters. USA Surf Team coach, Ryan Simmons, announced all the mock heats and

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Rank: 25
Score: 57.626816
Retrieved Text: Brazilian surfer Maya Gabeira has been credited with setting a world record for the largest-ever wave surfed by a female earlier this year.
The 31-year-old Gabeira caught the 20.72 meter wave in January off the coast of Nazare, Portugal.
The record was confirmed this week, and Gabeira was recognized for her achievement at a ceremony in Portugal.
It is the first time a woman was recognized for a biggest wave award in a separate category, something Gabeira herself had lobbied for since 2013.
That year she was knocked off her board and nearly drowned attempting to catch a giant wave in Nazare.

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Rank: 26
Score: 57.60615
Retrieved Text: Pro big-wave surfer Will Skudin, third from left, was honored by State Sen. Todd Kaminsky, center, for making the 2018-19 World Surf League’s Big Wave World Tour.
Skudin Surf and the Hurley Surf Club celebrated International Surf Day June 16, where hundreds of kids and adults received free surfing lessons with professional big-wave surfer Will Skudin and other seasoned athletes.
International Surf Day is held each year on or near the summer solstice, and is described as an environmentally conscious, sports-centered holiday that celebrates the sport and lifestyle of surfing, and the sustainability of ocean resources.
People of all different ages turned out to the event — sponsored by Hurley and held in conjunction with Skudin Surf — which was aimed at encouraging those who have never surfed to give it a try.
The event kicked off with a beach clean-up organized by the Surfrider Foundation Central Long Island Chapter, followed by free surf lessons courtesy of Skudin Surf.
The event is aimed in part to connect people to the ocean and create environmental awareness, he said, while also teaching newcomers proper swimming and surfing techniques — and having fun. Skudin and his fellow surfers explained the difference between plastic and single-use plastic containers and other products and handed out bamboo straws as an alternative to plastic straws.
“If we treat the earth and our surroundings like our home, we’ll be able to flourish,” he said.
Matthew Giannone, 13, said it was his first time surfing.
A Long Beach resident who grew up in a surfing family, Skudin is considered one of the best

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Rank: 27
Score: 57.266766
Retrieved Text: "Surfed my first wave in 1967. Starting shaping in '73. Board design was changing rapidly, and in order to stay current, I began to shape my own boards. I shape Hulls because of their unique feel, speed and effortless glide which, for me, provides the pure joy of riding a wave."

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Rank: 28
Score: 56.644226
Retrieved Text: Home Tips & tricks Are you a beginner or pro surfer?
Or are you a beginner, an intermediate surfer, advanced or even a pro?
You have either never surfed at all, or just a few times. On a good day, you can ride the white water of a broken wave and get up on your surfboard. You use a bigger surfboard (from a mini Malibu to a softtop).
You can surf down-the-line. You’re past the white water stage and you can surf to the left or to the right of the wave, depending on the direction in which the wave breaks. You also know how to make (slight) turns on the wave, and you can duck dive.
You can surf on smaller, as well as bigger boards. You’ve been on several surf vacations and you’ve surfed waves in different countries.
You can surf on several different types of surfboards. You paddle out without any issues. Even in challenging conditions with a strong current and bigger waves (higher than 2 meters). You easily surf rail to rail, and your cutbacks are solid. You have several different surfboards for different types of waves.
Or are you a Pro Surfer?
You easily navigate through reefs and/or point breaks. You’re always looking for barrels, if the waves are hollow. Your cutback is extremely accurate. Whether the wave is half a meter or 4 meters high doesn’t matter to you – you get the most out of every wave. You probably have an extensive quiver.

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Rank: 29
Score: 56.256683
Retrieved Text: The North Canyon Tow-In Trials presented by Wavejet is on high alert. The yellow flag has been raised and a big swell pump may ignite Nazaré, in Portugal, for perfect big wave riding conditions.
Tow in surf teams will face the power of the waves of Praia do Norte, where Garrett McNamara surfed the biggest wave of all time. The winning team will have a direct right to participate in the international big wave event that will take place until the end of the year 2012.
Ramon Laureano and António Silva (Portugal), Al Mennie and Andrew Cotton (Irlanda/UK), Axi Muniain and Jerome Sahyoun (País Basco/Marrocos), Yuri Soledade and Sebastian Steudtner (Brasil/Alemanha), Benjamin Sanchez and Eric Rebiere (França) and Will Skudin and Cliff Skudin (EUA) will battle for the golden ticket in the 2012 Xtreme Waterman Challenge.
The international big wave championship will be surfed Praia do Norte, Nazaré, as a culmination of a three-year project which started last year with The North Canyon Show project, by Garrett McNamara. This pioneering Portuguese event will showcase the best teams tow in surfing teams in the world.
"After exploring Praia do Norte, I think this is the most challenging place I've ever experienced. I am honoured to be hosting and very excited to see my friends surfing there", said Garrett.

================



======= Instance Index 1371 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are Tony's or Ian's ):

The higher the crests of a wave are, the greater the amplitude.


Ian surfed a 6 foot wave. Tony surfed a 10 foot wave. The wave with the highest amplitude was Tony's or Ian's?

Target Text: Tony's

#### Retrieved Documents ####

Rank: 0
Score: 73.27514
Retrieved Text: What is there left to do after you break a world record, except break it again? Hawaiian surfer Garrett McNamara, who in 2011 rode a 78-foot swell to claim the record for largest wave surfed, may have broken the record a second time. McNamara traveled to the coast near Nazare, Portugal, where he caught a wave reported to be around 100 feet.
The claim, however, has yet to be verified. Measuring a wave’s precise height is quite difficult and the only evidence is strictly visual. McNamara’s record-breaking 2011 wave, also in Nazare, became a source of controversy when it was originally estimated to be about 90 feet. It was brought down to 78 feet upon closer inspection, just one foot higher than that surfed by the previous record holder, Mike Parson.

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Rank: 1
Score: 70.66049
Retrieved Text: How Big Was the Biggest Wave Ever Surfed?
As of January 2013, Garrett McNamara, has surfed the biggest wave ever recorded surfed at 100 feet!
Garrett McNamara beat his record of the biggest wave surfed from 78 ft in November 2011.
Shawn Dollar holds the record for current paddle-in at 61 ft from May 2013.
The highest motorcycle jump is held by Robbie Maddison at 35 ft in January 2009.
The highest snowboard air on superpipe is 23 ft by Shaun White in January 2010.
And last, but definitely not least, the highest outdoor high jump at 8 ft by Javier Sotomayor on July 1993.
Fill out the form below to download the full size infographic.

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Rank: 2
Score: 68.85731
Retrieved Text: Lampung or many people says “Southern Sumatra” has many surfing location. Some place are very well-known by International Surfer.
This wave is an 800 meter long lefthander that wraps around the point and provides some great barrels and carving sections. It is really consistent and caters to surfers from the beginner to advanced. This wave can be ridden from 3 to 10 feet and is walking distance from the camp.
This wave is punchy, peaky beach break that turn on when everywhere else is flat. Expect lot of peaks and the opportunity to surf without your booties. 2-6 foot and fun.
This wave is a perfect short rampy tube ride. Best when the swell is massive everywhere else. Holds a flawless 2-4 ft. Really fun wave suitable for beginner to advance.
A really solid right hander that as great barrel section and some really challenging sections for manuveres. Holds from 3-8 foot and is a really long fun ride.
Mainly a wave for bodyboarders, a very sucky and steep, left barrel that is quick and heavy. Holds 3-8 foot and is for the experienced surfer and bodyboarder only.
A fantastic, heavy and brutal waves. Best surf on high tide when there is a lot of sweel. Book a driver or ride a motorbike for 2 hours to get there. It s a very deep barrel that holds 4-12 foot and is for the experienced surfer only. The end section is so scary it should only be surfed on high tide. Also has a left hander for the adventurous.
*all data based on the

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Rank: 3
Score: 68.578705
Retrieved Text: Big wave rider Mark Visser has entered the History of Surfing. The pro surfer has surfed 30-40 foot waves in a night ride off the shore of Maui, Hawaii. It's not the apocalypse, it's surfing breaking its own frontiers.
The 28-year old Australian used a special surfboard with built-in LED lights, engineered by NASA for submarine lighting. The red light ensured that the helicopters and jet skiers were able to spot where Visser was riding each wave.
This is the first time a surfer tries to ride big waves in the dark. Mark prepared this project for two years. "It is the most exciting thing I have ever done. It wasn't until I saw the pictures I realized how big it was," said the intrepid surfer.
Mark has hit the waters at 2am, in complete gloomy conditions. Watch how he surfed his night waves. It looks like he's a surfer from the future, with jet-powered fins. How crazy is that?
Riding huge black waves isn't easy and Visser got the helping hand of the tow-in jet skis. "Riding in complete darkness meant I had to go off feeling. I had to zone out from how you normally ride and just be part of the wave. I am so pumped to achieve something that no one thought possible and that I was told that it couldn't be done."
Mark Visser is planning a full-length documentary named "The Night Rider," to be broadcasted late 2011, early 2012. In the past, Visser is known for riding big waves and placing in the Top 10

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Rank: 4
Score: 67.66952
Retrieved Text: Action starts with Professional Big Wave Surfer Toby Cunningham getting towed into a massive wave in Nazaré, Portugal, during the big wave session of February 7, 2019, which was one of the biggest days of this Winter season in Praia do Norte.
After successfully riding the huge wave, which was the first wave of a big set, Toby gets caught by the white water and falls off his surfboard. By then Toby was further in the inside, which is the most dangerous spot in Praia do Norte, also known as the impact zone. His rescue teammate, Surfer Glyn Ovens tries to reach him with the Jet Ski, but there’s little opportunity for a pick up since the next wave was already too close. Toby takes the first impact of a giant mass of white water, and as he resurfaces Glyn was already getting close with the jet ski to attempt another rescue, but Toby sees another huge wave rolling in and signals Glyn to abort the pickup, taking that second enormous impact on the head. The moments that follow were of great stress, and little window of opportunity for a successful rescue, Toby’s 25 years of Big Wave experience is put to the test, he manages to stay calm under pressure and eventually gets picked up by Brazilian Surfer Ian Cosenza that came in to help with the rescue.
Besides Surfing Big Waves, Toby’s other passions involve Global Finance and Crypto Currencies (he helps running “Crypto Tips” Channel on Youtube), he does volunteering in India at the Mother

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Rank: 5
Score: 67.42462
Retrieved Text: McNamara (in 2013 in Nazaré) still surfs its monster waves, despite the risks. Last year, a fall broke champion British surfer Andrew Cotton's back.
... wave off Portugal has produced a world record for a Brazilian surfer. The World Surf League says Rodrigo Koxa has ridden the biggest wave ever surfed.
Biggest wave ever surfed: Rodrigo Koxa's record ride!
April 30, 2018 8:21am EDT April 30, 2018 8:21am EDT A Brazilian surfer now holds the Guinness World Record for the biggest wave ever surfed.
In extreme sport, the world record of the biggest wave ever surfed has just been officially defeated announced Sunday, April 29, the World Surf League.
Evan Kirstel on Twitter: "🌊 🏄 Dude! > #Brazil's Rodrigo Koxa sets record for biggest wave ever surfed #SundayMorning #surfer https://t.co/5FA5rt31S7"
Nazaré causes confusion: Who surfs the biggest wave in the world?
Brazilian surfer Rodrigo Koxa set a new Guinness World Record for riding the biggest wave ever surfed, an 80-footer in Nazaré, Portugal.
Watch Brazilian surfer Rodrigo Koxa break the world record for the largest wave ever surfed.
The world record for largest wave ever surfed now belongs to Brazilian surfer Rodrigo Koxa. Watch his historic run.

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Rank: 6
Score: 65.06225
Retrieved Text: After a week of forecasting, planning and preparation, Team WRSC scored one of the most memorable days of the year at the famous, Ollie’s Point. With not a drop of water out of place, Team WRSC surfed machine-like 4-6ft right-hand barrels for over 6 hours! The waves never seemed to stop, and with over 500 waves ridden throughout the day, we concluded our journey with noodle-arms, salty skin, and smiles from ear to ear.
Chief Operating Officer, Pat McNulty grabbing the first wave of the day and showcasing his classic style with over 50 years of surfing experience.
Even the birds were getting tubed!
Reservations Julie putting on a show for the boys.
Drag your hand and pull in!
Strong emotions after 3 tubes on 1 wave!
Julie dropping in and waiting for the wave to open up.
When Joe Walsh claims this was one of the best days he’s surfed Ollie’s in the past 15 years, we all felt very humbled. Here’s the legend himself setting up for the tube!
Sets out the back!! More style with Niki.
Pat setting up for the tube. The waves this day barreled perfectly from the point all the way to the beach. 45 seconds of regular foot perfection.
Brian racing the inside tube section!
Enjoying a refreshing Witch’s Rock Pale Ale after a long day of surf.
This is how it goes. Niki makes the beer, Joe drinks the beer.
Ending the day with cold beer and smiles from ear to ear.
Big thanks to Shaka Media for the photos and WRSC for an amazing group with positive vibes. We will be

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Rank: 7
Score: 64.303566
Retrieved Text: It’s no surprise surfers have a natural affinity for the ocean and it’s waves. However, select surfers have the bold and daring nerves to conquer some of the largest swells in the ocean. Although measuring the exact height of a wave is challenging, most waves are larger than they appear. Thanks to YouTube these surfing swell videos have gone viral, and are a source of inspiration for future surfers to overcome fear and conquer the wave of their dreams.
Check out some of the original surfers to conquer some of the largest surf. Names like Eddie Aikau and Greg Noll make waves for future surfers. The Quicksilver Big Wave is named in honor of Aikau, who lost his life at sea in 1978. Noll became famous in 1957 for surfing giant swells known as the Pipeline in the Wiamea.
Laird Hamilton takes on the giant waves filled with mass, power and velocity. What seems like a death-defying stunt comes out with a possible belief that conquering something imaginable is possible even in the ocean. This break in Tahiti is known as one of the most dangerous wave in the world.
Shane Dorian and Mark Healey paddle the waves at Waimea Bay for some after storm swells. With the crowd surfing and a giant black wall of water, these two lucky surfers successfully caught this monster.
Explore some massive swells from the 2009 Billabong XXL event. The four minutes of footage is nonstop riveting action in Maui. From successes to wipeouts, these are the bset of 2009 Jaws.
Surfer Ken Bradshaw chats

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Retrieved Text: “Um, I reckon we should get out there yay”.
Two weeks of Mentawai perfection on board The D’Bora.
Two weeks of Mentawai perfection on board The D’Bora was scored in Early August by a mixed crew from Angourie/Yamba plus a couple from the Goldy.
Tracks caught up with Blakey Wolfe, a 30-year-old surfer from Angourie and got his take on the trip.
We surfed everyday! Our first seven days couldn't have been better with 4-8ft epic waves the whole time. Our last four days we had fun waves around 3-5ft.
We were lucky enough to have two solid swells, the first swell was from the west which is when we scored HT's and the next was from the south. We were lucky with the wind. It was light and variable most of the time. I heard August normally has stronger winds.
We had one epic whole day at HT's, 6-8ft no wind all day.
HT's, Roxy’s, Macca’s, Lances Left. We surfed Greenbush on the wrong swell direction so it was closing out at the end, would love to surf it perfect.
Ha ha, this wave took me most of the first day to figure out. It's a lot heavier and shiftier than I thought it would be, especially at 6-8 foot. On a 6ft+ set you kinda get a roll in take off but not a real easy one, then you want to just set up for the barrel section and once your in, you really need to pump through the barrel to make sure you get out and avoid the 'Surgeons Table' (the

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Rank: 9
Score: 62.737408
Retrieved Text: One of the primary reasons for travelling around Australia was for Dean to surf as many beaches as possible. The following is what he had to say about the waves he found.
Just north of Margaret River you come to Yallingup – a nice quiet little sea-side town. We were there for just over a week and, although the surf had dropped back, there was a few waves to be ridden.
Yallingup reef is a very nice left hand break and I did manage to get a few 3 to 4 foot waves that provided a good 150 metre ride.
I was just a little disappointed that it didn’t really turn on while I was there. Another great spot for a surf all the same.
What can I say about this great Aussie surf destination – WOW I can now say I have surfed this iconic wave.
Spent five days here but when we first arrived it was only small – 2 to 3 foot and that was fun, but over night the swell rolled in and the sets were up to 8 feet. Now to me that’s pretty big.
I did managed to catch a few and it did get the adrenalin flowing, but alas on my last day, I snapped my board when I had to bail off it to dive under a breaking wave. Rather my board than my back. And I wasn’t the only one, I saw a few get snapped while I was there, but it was definitely worth it.
Make sure you get to this spot –

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Retrieved Text: Hound of the sea – that’s the name of the book about Garrett McNamara, legendary big wave surfer who’s surfed the biggest wave that most certainly has ever been surfed. Follow Garrett to Lofoten, Norway, and get to know the man inside the wet suit.
Garrett has been a friend of Thule since many years back and he’s a great inspiration to many people around the world. But more importantly, he uses his success and fame to inspire and teach the young generations powerful and important lessons of life. Garrett believes that we must encourage our children to follow their dreams. And we must take care of the environment. Otherwise there will be no ocean to play in, no snow to ski on and there will be no woods to run in. The world was lent to us by our parents, it’s up to us to be responsible and to leave a healthy environment for our children!
Garrett GMAC McNamara is the legendary big wave surfer who’s still holding the Guinness World record of biggest wave ever surfed, in Nazaré 2011.

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Retrieved Text: With a warm smile, Emily Erickson will invite you to go surfing with her. And you will nervously ask: Uh, where?
Erickson’s introduction to surfing began at Sunset Beach on Oahu’s North Shore, which some would argue is like starting your climbing career on Mount Everest.“Because my dad surfed there, I never thought it was impossible,” she says. “There were no limits.
As a child in Hawaii, Erickson watched her father, Roger, a big-wave legend and former North Shore lifeguard, ride giant swells while she played in the sand. At 17, she began learning about the ocean and its moods on a boogie board. A year later, her father gave her his 10’6″ big-wave gun. Erickson was hooked. “Nothing hit me as hard as surfing did,” she says.
Erickson never expected to grace the cover of The Surfer’s Journal or get nominated for two Billabong XXL awards. Still, finding sponsors is a struggle many female big-wave athletes face. Among other projects, Erickson waits tables at a sushi restaurant to make ends meet. But she has found a different kind of richness in the sport. “On big waves especially, I have this hyperaware, instinctual experience that makes me incredibly high and so happy,” she says.
At last year’s first WSL women’s big-wave competition at Jaws, on Maui’s north shore, Erickson saw a wave she thought could be a winner. As she rocketed down the nearly 40-foot face, the wind flipped her board sideways and spun her upside down. She tore her ACL, MCL, quad, and calf muscle.

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Retrieved Text: Two years ago, when John Florence won The Eddie, the buoy readings were 20 feet at 16 seconds, and the biggest sets were closing out the channel at Waimea Bay. It was so heavy that, after the contest ended, only a few guys braved a freesurf.
North Carolina’s Mason Barnes, a soft spoken, 24-year-old under-the-radar big wave guy, was one of them.
In the years since, we’ve seen photos of Barnes popping up at all the premiere big-wave spots around the world: Jaws, Puerto, Mavs, Cortes Bank, and… Tres Palmas?
Tres Palmas, in northwest Puerto Rico, is known to produce big waves during large winter swells. But thanks to winter storm Riley and its once-in-a-decade buoy readings (20 feet @ 16 seconds just off the coast of PR), Tres went XXL, and Barnes, along with a small crew of fellow east coasters, was there to experience an Eddie sized swell close to home.
We gave Barnes a ring to hear about his experience.
How you feeling after these last couple of days?
Good! But I’m so fried. So sunburnt. I just got in from the water 10 minutes ago. It was a pretty awesome day over here.
20 feet at 16 seconds happens once in a decade in the Caribbean. If that. What were your first thoughts when you saw this swell forecast?
I had no idea what to expect. I knew the numbers were there, but you still never know if it’s actually gonna translate in the Caribbean. I got here super early Sunday morning, and I was so blown away by how

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Score: 60.15026
Retrieved Text: Some TGSA U18 members recently participated in the Surfing America Prime Series event at Steamer Lane in Santa Cruz, CA. It was a great opportunity extended to TGSA by Surfing America. Board member Rob Henson worked to put this opportunity together for some of our top competitors and we asked him to give us a summary of the trip. Thank you Rob for your hard work and thank you Greg Cruse and Surfing America for welcoming the Texas kids and your hospitality during the trip.
The Surfing America Prime Series took over Steamer Lane in Santa Cruz, CA January 10th and 11th. The TGSA was invited to bring some of our top surfers out the the contest as well as participate in a “mock” heat on Friday January 9th. Tyler Bacquet, Nathan Marney, Kelly Scroggs, Ian Appling, Aransas Blaha and Maddie Garlough arrived in Santa Cruz on Tuesday Jan 6th and immediately took to the water. Although the surf was fairly small the first few days, we were greeted with 4-6 feet surf on Friday which slowly faded on Sunday. The biggest concern for the groms was getting used to taking off at the “SLOT” which is right next to the cliff. I was really proud of the way they adapted to the conditions and became comfortable with the break. On Friday, Tyler Bacquet was placed into a mock heat with current USA Surf Team members and definitely caught the attention of the west coasters. USA Surf Team coach, Ryan Simmons, announced all the mock heats and

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Retrieved Text: Perfect, barreling right-hander from the BSR Surf Ranch in Waco, TX.
While the world has been laser-focused on Kelly's Wave -- aka Surf Ranch by Kelly Slater Wave Co. in Lemoore, CA -- a sleeping giant has been in the background creating arguably better, more perfect waves. Enter into the equation American Wave Machines (AWM), a Solana Beach, CA, company that has their own unique approach to creating the perfect wave for surfing.
BSR Cable Park and American Wave Machines teamed up to build a one-of-a-kind wave pool in Waco, Texas. The BSR Surf Resort debuts the Perfect Swell technology, and will create all types of waves with short intervals between them. The size of the waves will vary between 3 and 8 foot.
Historically, surfing has been limited to coastal destinations with bodies of water in front of them. AWM aims to take surfing, the world's most aspirational sport, inland to populations that may not have beach access.
Inspired by footage of Oahu's Waimea river blown out, flowing and being surfed by locals...AWM began research and development on the world's first artificial standing wave, SurfStream®. Testing started with a 1/12th scale model in founder Bruce McFarland's backyard. Then, in 2004, the first rideable prototype was installed into shipping containers and tested by local New Jersey surfers. Since then, incremental improvements of the technology and a growing interest in surfing outside of the ocean has led to the opening of more than a dozen SurfStream® surf parks worldwide.
With Surfing making its premier appearance at the 2020 Olympic Games in Tokyo,

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Score: 59.881683
Retrieved Text: Charlie had a big decision to make. He and his friend Javier were being offered professional surfing contracts with Rip Curl Men. Charlie and Javi were of course happy, but they also didn’t know if they wanted this life. Surfing was a dangerous sport, and if they accepted the contract they would be surfing pipeline all day everyday. Pipeline was the third most dangerous wave to surf, next to 100 foot-waves and Mavericks.
Charlie was really taking this into consideration. He had a family to worry about. He knew his wife wasn’t that happy that he was a big time surfer because her father had died surfing pipeline. Javier was not as good of a surfer as Charlie , but he wasn’t a very popular one. Charlie had made millions of dollars but Javi only made a few thousand.
Charlie called Javier around 4:30 am. “Hey man, they got a major swell coming in in about twenty five minutes. If you’re interested I’ll be at Waikiki Beach.” Charlie headed up to the beach, and what he saw was one of the prettiest sights he had ever seen. The waves were bigger than he expected, they were rising to at the least 39 feet. These were Mavericks. Charlie knew Javi wasn’t trained to surf these big of waves. Charlie and Javier paddled out, it was rougher than it looked. Charlie could see a big time wave in the back, he waited a few seconds until the wave grew closer. He started to paddle as fast as he could, and

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Score: 59.72121
Retrieved Text: Rarely surfed, some okes paddle out here when factory is too crowded. The wave breaks a shallow flat ledge.
English (Traduzir este texto em Português): Rarely surfed, some okes paddle out here when factory is too crowded. The wave breaks a shallow flat ledge.
Best left for the pros.
English (Traduzir este texto em Português): Best left for the pros.

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Score: 58.60845
Retrieved Text: Brazilian pro-surfer, Rodrigo Koxa recently became another record-holder. He officially broke the record of the largest wave ever surfed at the Nazare Beach in Portugal and received a Guiness World Record on the 30th of April. The surf was actually made last year on November the 7th, which was made official at World Surf League’s Big Wave Awards, where he also accepted the Quiksilver XXL Biggest Wave Award for biggest wave of the year. The height of the wave was a massive 80 feet (or 24.5 meters).

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Rank: 18
Score: 58.49165
Retrieved Text: For two years running, or padding, Nazaré, Portugal has dominated surf headlines. There the world record sized waves have been successfully surfed, mountainous waves that crash into huge rocks on razor sharp coastal cliffs. I’ve seen it, it’s pretty damn scary, I wouldn’t do it.
Longer rides have been surfed and documented. Pororoca in the Amazon’s tidal bore; 45 minutes on one muddy wave in a very remote jungle. Robby Nash cruised for 3.03 minutes on a nice wave off a beach somewhere in the Pacific, he had a paddle. Winter in Lagos may not be the high tourist season, unless you travel with a wet suit and your car has a roof rack. I’m still wondering how Alex Botelho, after his 1 minute and 40 second record breaking ride, got back to where he started. Unlike the Nazaré surfers who bravely face breaking the latest record, Alex didn’t plan this, there wasn’t a massive support team ready to whisk him to the media tent, then to his deluxe suite somewhere. Alex was just having fun.
This entry was posted in ex-pat in lagos, Ex-Pats Abroad, Lagos, Lagos Portugal friends, Lagos Pt history, Portugal, Surfing, Travel and tagged Alex Botelho, Duke Kahanamoku, longest wave surfed in Portuga, Surf Lagos Portugal. Bookmark the permalink.
Awesome. I would have given him a free ride.
It’s actually a cool and useful piece of info. I am satisfied that you shared this helpful info with us. Please keep us up to date like this. Thank you for sharing.

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Rank: 19
Score: 58.36228
Retrieved Text: A 10-year-old surfer surfed with a great white shark.
Eden Hasson was catching his last wave, while surfing at Samurai Beach in NSW Tuesday evening.
← Donna West IS our Working Woman!

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Score: 58.341114
Retrieved Text: A 14-strong team has surfed into the world record books by riding a wave on a single giant surfboard in Cornwall. The record bid was held at St Ives, on a 37-feet board weighing 400lb.
On their fourth attempt the team of 12 men and two women stood up and surfed into shore together, setting the first official world record for the most people riding a single board. The team included the cream of British surfers, as well as an Australian and three South Africans. Britain's surf champion Alan Stokes, 22, said riding the two feet wave with his team was not easy.
The fibreglass board - officially the longest in the world - set an unofficial record when it was first used by a team of 12 people at its launch in Cornwall in 1999. A New Zealand team went one better and managed to get 13 people riding a wave on one board.
The giant longboard was created by team member Tim Mellors at Custard Point boards in Newquay. It will now go back on display at the town's Longboard House shop.

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Rank: 21
Score: 58.314022
Retrieved Text: Best for: People who have a little experience on a surfboard and can paddle and catch a wave by themselves to surfers who are just getting familiar with a short board. Also fine for complete beginners if accompanied by an instructor/guide.
Crowd factor: medium - high. Gets very crowded at times, one of the most popular spots especially when the conditions are good. Due to this being a beautiful spot to teach lessons and the soft, easy nature of the wave, Daku is a favorite wave for many resorts to take their guests.
How to get there: You can find boats for hire by the market / boardwalk in General Luna. It takes about 15 minutes each way and the driver will wait for you (or surf with you) and take you back for 200 pesos per person (min 2 pax).
Kind of wave: Daku is best surfed at about shoulder high and with light, offshore (west) winds. When these conditions line-up Daku is one of the best waves in the world to surf. Slow, soft take-off onto a decent sized right-hand wave that goes on forever in the most beautiful scenery you've ever seen. These conditions are most often seen in the peak season of late Aug to November.
Daku can be surfed any time of the year that the winds are light or off-shore and there's a decent sized swell. It doesn't work too well through the winter (choppy because of on-shore or cross-shore winds) and it's usually flat in the summer months. Ideal conditions are most often

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Rank: 22
Score: 58.161774
Retrieved Text: Nazaré, Portugal is home to some of the biggest, most exciting waves on the planet, making it ideal for the big-wave surfing community. With swells the size of skyscrapers, this location brings together surfers from all over the world, each trying to catch their own monster ride.
On November 10, 2011, Garrett McNamara did just that, surfing what was then considered the tallest wave ever ridden. And to everyone’s enjoyment, the 44-year-old Hawaii pro surfer filmed the entire event on video.
This week, after a panel of big wave and photography experts analyzed the footage, Guinness World Records officially certified McNamara’s wave as the ‘Largest Wave Ever Surfed’ at 78 feet.
It may not stand for long, though—check out this video of him surfing a 100-footer in 2013, which still has yet to be certified by Guinness World Records.

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Rank: 23
Score: 58.09685
Retrieved Text: I went to short sands mid-morning on Friday, July 1st. Overnight and in the early morning the winds were light and the surf forecast was 6-8 foot (which is huge), medium period, semi-glassy in AM moving towards junky in the PM as winds picked up. The tide was low right about 8:30 which meant that it was difficult to take advantage of the best wind/surf combination of the day. But I went anyway, surfing from about 10:30 am to about 12:00 pm, on the first half of the rising tide.
Round these parts surf conditions cannot approach ideal unless you have a rising mid-to-high tide coinciding with the morning’s low and/or the afternoon’s offshore winds, combined with a significant wave with low period (4+ feet, 10+ seconds).
The forecast had me thinking that Friday would the first day where I could even get close to this kind of situation. But it turns out it was far from ideal.
The winds were a strong NW (oriented like N given the angle of Short Sand beach), and way higher than forecast for the late morning. They screwed everything up. Plus, the waves were junky and complicated by a multiple cross swell and local wind waves. And moreover, not having surfed for six months, it felt like nothing was working right for me.
My huge and heavy single-fin 9′ 6″ Bruce Grant Super Ugly board was a liability rather than any kind of aid in the pounding beach break. Once I got outside the break zone, the southbound current caused by the 10+

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Rank: 24
Score: 57.930305
Retrieved Text: The Maldives has the coolest airport I have ever been to!
On its own island and only 20 meters from the airport exit, there is a huge wharf with taxi boats (Dhonies) that take us to the Cobia surf charter boat which is a very rad experience.
We surfed head high waves down south at Tucky Joes, Quarters, Rip Tides, Jailbreaks and Sultans.
We then surfed our way up north, finishing up at pumping 6 foot+ Cokes and Chickens.
The waves are generally softer than what I am used to in Indonesia.
11-13 second period swells in the Maldives compared to 15-22 second period in Indonesia.
Still big and powerful, but not as round or as much variety as in the Mentawais, but the Maldivian reefs will still give you a beating if you get caught out.
The Maldives are perfect for intermediate surfers, and caters well to family groups.
There are a couple of heavy barreling waves like Tucky Joes and Cokes, but they need a few different variables to come together to pump, so it can be a bit hit and miss.
There was no shortage of swell in July, in fact most of us were under gunned with our board selection.
We had many overhead days. Don’t get caught out like us! The currents are strong during spring tides, the extra foam and couple extra inches makes everything more fun.
We had a great trip, fun times and plenty of waves in a very beautiful part of the world.
Thanks to Trevor, The Perfect Wave and Cobia surf charter for an unforgettable experience.

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Rank: 25
Score: 57.626816
Retrieved Text: Brazilian surfer Maya Gabeira has been credited with setting a world record for the largest-ever wave surfed by a female earlier this year.
The 31-year-old Gabeira caught the 20.72 meter wave in January off the coast of Nazare, Portugal.
The record was confirmed this week, and Gabeira was recognized for her achievement at a ceremony in Portugal.
It is the first time a woman was recognized for a biggest wave award in a separate category, something Gabeira herself had lobbied for since 2013.
That year she was knocked off her board and nearly drowned attempting to catch a giant wave in Nazare.

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Score: 57.60615
Retrieved Text: Pro big-wave surfer Will Skudin, third from left, was honored by State Sen. Todd Kaminsky, center, for making the 2018-19 World Surf League’s Big Wave World Tour.
Skudin Surf and the Hurley Surf Club celebrated International Surf Day June 16, where hundreds of kids and adults received free surfing lessons with professional big-wave surfer Will Skudin and other seasoned athletes.
International Surf Day is held each year on or near the summer solstice, and is described as an environmentally conscious, sports-centered holiday that celebrates the sport and lifestyle of surfing, and the sustainability of ocean resources.
People of all different ages turned out to the event — sponsored by Hurley and held in conjunction with Skudin Surf — which was aimed at encouraging those who have never surfed to give it a try.
The event kicked off with a beach clean-up organized by the Surfrider Foundation Central Long Island Chapter, followed by free surf lessons courtesy of Skudin Surf.
The event is aimed in part to connect people to the ocean and create environmental awareness, he said, while also teaching newcomers proper swimming and surfing techniques — and having fun. Skudin and his fellow surfers explained the difference between plastic and single-use plastic containers and other products and handed out bamboo straws as an alternative to plastic straws.
“If we treat the earth and our surroundings like our home, we’ll be able to flourish,” he said.
Matthew Giannone, 13, said it was his first time surfing.
A Long Beach resident who grew up in a surfing family, Skudin is considered one of the best

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Score: 57.266766
Retrieved Text: "Surfed my first wave in 1967. Starting shaping in '73. Board design was changing rapidly, and in order to stay current, I began to shape my own boards. I shape Hulls because of their unique feel, speed and effortless glide which, for me, provides the pure joy of riding a wave."

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Score: 56.644226
Retrieved Text: Home Tips & tricks Are you a beginner or pro surfer?
Or are you a beginner, an intermediate surfer, advanced or even a pro?
You have either never surfed at all, or just a few times. On a good day, you can ride the white water of a broken wave and get up on your surfboard. You use a bigger surfboard (from a mini Malibu to a softtop).
You can surf down-the-line. You’re past the white water stage and you can surf to the left or to the right of the wave, depending on the direction in which the wave breaks. You also know how to make (slight) turns on the wave, and you can duck dive.
You can surf on smaller, as well as bigger boards. You’ve been on several surf vacations and you’ve surfed waves in different countries.
You can surf on several different types of surfboards. You paddle out without any issues. Even in challenging conditions with a strong current and bigger waves (higher than 2 meters). You easily surf rail to rail, and your cutbacks are solid. You have several different surfboards for different types of waves.
Or are you a Pro Surfer?
You easily navigate through reefs and/or point breaks. You’re always looking for barrels, if the waves are hollow. Your cutback is extremely accurate. Whether the wave is half a meter or 4 meters high doesn’t matter to you – you get the most out of every wave. You probably have an extensive quiver.

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Rank: 29
Score: 56.256683
Retrieved Text: The North Canyon Tow-In Trials presented by Wavejet is on high alert. The yellow flag has been raised and a big swell pump may ignite Nazaré, in Portugal, for perfect big wave riding conditions.
Tow in surf teams will face the power of the waves of Praia do Norte, where Garrett McNamara surfed the biggest wave of all time. The winning team will have a direct right to participate in the international big wave event that will take place until the end of the year 2012.
Ramon Laureano and António Silva (Portugal), Al Mennie and Andrew Cotton (Irlanda/UK), Axi Muniain and Jerome Sahyoun (País Basco/Marrocos), Yuri Soledade and Sebastian Steudtner (Brasil/Alemanha), Benjamin Sanchez and Eric Rebiere (França) and Will Skudin and Cliff Skudin (EUA) will battle for the golden ticket in the 2012 Xtreme Waterman Challenge.
The international big wave championship will be surfed Praia do Norte, Nazaré, as a culmination of a three-year project which started last year with The North Canyon Show project, by Garrett McNamara. This pioneering Portuguese event will showcase the best teams tow in surfing teams in the world.
"After exploring Praia do Norte, I think this is the most challenging place I've ever experienced. I am honoured to be hosting and very excited to see my friends surfing there", said Garrett.

================



======= Instance Index 338 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are Bill or Will ):

In electromagnetic waves with higher frequencies, photons have more energy.


Will analyzes the photon energy in an electromagnetic wave with a high frequency. Bill analyzes the photon energy in an electromagnetic wave with a low frequency. Bill or Will's wave has less photon energy?

Target Text: Bill

#### Retrieved Documents ####

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Score: 72.181786
Retrieved Text: antenna, even though the antennas may be miles apart.
, which we will study later this quarter.
In the case of a sine wave, we associate a wavelength with a given frequency.
crest of the wave shown in Figure 2.3 above or below its midpoint.
relation given by Equation 2.2.
expressed in 1/seconds, to which we assign the name Hertz (Hz).
describe electromagnetic radiation as sine waves of a given wavelength and frequency.
meters per second, the speed of light.
refraction for some common materials.
index of refraction of light in a diamond?
The amount that light is refracted depends on the frequency of the light wave.
radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.
the longest wavelengths and lowest frequencies.
generator and receiver will be demonstrated in the classroom.
the infrared portion of the spectrum.
separate white light into the colors of the visible spectrum.
induce fluorescence and can cause tanning in human skin.
ray photographs can show bone structure and assist the medical profession in diagnosis.
nuclear reactions and will be discussed further in the period on nuclear energy.
relation shown in Equation 2.4.
indication that we still do not have a full understanding of this phenomenon.
b) How much energy does each photon of this radiant energy have?
photon energy for radiant energy.
radiant energy. This energy is associated with an electromagnetic field.
light and is given the symbol c.
2.2:Radiant energy can be thought of as a wave with a wavelength and frequency.
As light passes from one medium to another it is refracted, or bent.
index of refraction, n, of the material.
infrared radiation, visible light, ultraviolet light, X–rays, and gamma rays.
e) All of the above travel at

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Retrieved Text: With the development of Photoelectric effect, Crompton’s effect and Bohr’s model of atom, the idea of light or in fact radiations in general, being composed of particles or discrete Quanta was gaining wide popularity.
However, the very established Huygen’s Principle and the results of Young’s double slit experiments made it very clear that light was wave and not a flow particles.
The striking interference pattern observed by passing light through double slits was definitely a result of the wave nature of light. This again gave rise to the controversy of nature of light. In 1704 Newton had also suggested the particle nature of light by his corpuscular theory.
Where, h is Planck constant and p = mv, v is velocity of the body.
Thus due the huge mass of an elephant it has a very significant momentum and hence a very small wavelength, which we are unable to notice. However small particles such as electrons, etc. have very small mass and hence very noticeable wavelength or wave nature. This theory of de Broglie also helps us to explain the discrete existence of orbits in Bohr’s model of atom. An electron will exist in an orbit if its length is equal to integral multiple of its natural wavelength, if it is unable to complete its wavelength then that orbit will not exist.
Further developments by Davisson and Germer of electron diffraction from a crystal and a similar interference pattern obtained after bombarding a double slit with electrons had strengthen de Broglie’s matter wave theory or the wave particle duality theory.
In the photoelectric

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Retrieved Text: In his very first paper published in 1905 Einstein establishes the concept of “energy quanta” or “light quanta”. The manifestation of light quantum (photon) becomes more pronounced as the frequency of radiation increases.
In his paper Einstein analyzes the work done by Wien and Planck on Black Body radiation [see Black-body radiation (Notes)] and makes the following fundamental observations.
According to Maxwell’s theory, the energy must be considered to be a continuous function in space for all purely electromagnetic phenomena, thus also for light.
According to Kinetic Theory of gases, the energy in a volume can be written as a sum of energy of a finite number of particles localized in space, which move without being divided.
The classical treatment of energy as a continuous function in space fails to predict the energy spectrum observed for the black body radiation.
Max Planck’s postulate, “energy is proportional to the frequency of radiation” completely predicts the energy spectrum observed for the black body radiation.
Planck’s equation provides the classical results for low frequencies, showing that radiation energy is a continuous function in space at low frequencies only.
Using Wein’s law that matches experimental observations of black-body radiation at high frequencies, Einstein proves the energy behavior of radiation to be particle-like. From this arises Einstein’s proposal of “energy quanta” or “light quanta”.
Einstein’s demonstrates that the use of “statistical probability” by Boltzmann is compatible with the principles of physics, and they can be used to estimate the magnitude of such energy quanta.
The idea of energy quanta is compatible with the observations made in photoluminescence resulting in the

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Retrieved Text: It was subsequently recognised that a whole spectrum of electromagnetic radiation exists, from the short wavelength gamma-rays and X-rays at one extreme, through the more familiar regions of ultraviolet radiation, visible light and infrared radiation, to the long wavelength phenomena of microwaves and radio waves at the other.
The wavelength and frequency of each type of electromagnetic radiation are related by the simple equation: wavelength x frequency = speed of light, about 300,000 km/s.
This recognition of light as a wave phenomenon had in fact overturned two centuries of belief, dating back to work by Isaac Newton, that light was composed of a stream of particles.
It was observed that when light fell on a metal surface, electrons could be emitted by the metal.
Changing the intensity of the light caused the number of electrons emitted to change, but the electrons’ range of energies remained the same.
Decreasing the wavelength of the light, however, caused the electrons to be emitted with a higher maximum energy. Conversely, increasing the wavelength of the light beyond a particular cut-off value (specific to each metal), caused the emission of electrons to cease.
The explanation was that light interacts with matter as if it is composed of a stream of particles, now called photons. Each photon carries a specific amount of energy, which is directly related to the frequency used to characterise the propagation of light by the relation: energy of photon = Planck’s constant x frequency.
So light, and all other electromagnetic radiation, is now recognised as something rather strange: it propagates as if it is a

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Retrieved Text: The Photon Band, also called the Photon Belt, or Manasic Ring, is an immense region of space, 760 billion mile wide. It is a toroidal, or ring shaped field of energy, giving out intense electromagnetic radiation. It is made up of Photons, which are defined as the smallest divisible unit of light energy.
When astronomers first discovered it, they thought it was an unusual nebula, a vast cloud of gas and dust and they called it the “Golden Nebula”.
The Photon Band encircles the Pleiades Star Cluster at a right angle to its orbital planes. Our solar system is the 8th star in the Pleiades star group, orbiting Alcyone, the central sun of the Pleiades.
Our solar system completes this journey once in every 26 000 years. During that time, it is in the Photon Band twice, spending 2000 years in it each time. The 10 500 years out of the Photon Band is referred to as the “Galactic Night”.
Being in the Photon Band is a spiritual experience. The Photon energy transforms and transmutes, alters consciousness, giving opportunities for both spiritual and technological developments.
It was discovered in 1961 by means of satellite born instrumentation. In the early 1980’s there was a radio announcement that our solar system will collide with an electromagnetic cloud in the not too distant future.
Currently, Mainstream Science proclaims that this is only a New Age belief. Information on it is being suppressed. Astronomers who discussed the Photon Band lost their jobs, or have been denied access to equipment required to study it.
Yet, government scientists have

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Retrieved Text: Explain what the electromagnetic spectrum is and how scientists use it.
So far we have learned about the atom, the phenomenon of radioactivity, and we have looked at both nuclear reactions and X-ray generation. We already know that X- and gamma rays differ only in their source of origin or how they are generated. There are, however, very distinct characteristics associated with these energy forms. Two key points to remember about the characteristics of radiation are that X- and gamma rays are not bits of matter, they are electromagnetic wave forms possessing no charge and no mass, and they can be characterized by frequency, wavelength, and velocity. Let's take a closer look at the characteristics of these wave forms so that we may better understand the nature of them.
X- and gamma rays are part of what scientists refer to as the electromagnetic spectrum. They are waveforms that are part of a family in which some of the relatives are very familiar to us, such as light rays, infrared heat rays, and radio waves. However, X- and gamma rays cannot been seen, felt, or heard. In other words, our normal senses cannot detect them. Since X- and gamma rays have no mass and no electrical charge, they are not influenced by electrical and magnetic fields and will travel in straight lines. Continued research over the years since Roentgens discovery indicated that the radiation possesses a dual character. Acting somewhat like a particle at times and like a wave at other times. The name that has been given to

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Retrieved Text: As scientific discovery has advanced in the world of quantum physics, so has our understanding of chi. More specifically: whereas our foundational proposition is built around the concept that chi is electromagnetic energy that is composed of the quanta, we now have a greater specificity regarding the quantum energy we associate with chi. With that information, we are better able to engage, develop and manipulate the energy to achieve desired results, on demand and on command, all the while minimizing negative side effects that adversely impact the practitioners and those with whom they come in contact.
As noted above, we begin first with electromagnetic energy [radiation]. The electromagnetic spectrum of radiation encompasses all forms of energy. To that end, it is Universal in kind, and specific by type. This is to say that electromagnetic energy permeates the Universe, flowing into and through every known [and as yet to be discovered] object on some level. Depending on the frequency or wavelength, the electromagnetic energy takes a specific form, be it: X-ray; radio wave; microwave or; visible light. For example, electromagnetic energy that falls within the “ultraviolet” range cannot penetrate the Earth’s atmosphere [ozone layer]. Radio waves, conversely, travel across and throughout the known Universe with little to no impediments.
The article “Energy Healing and the science of Bio-Photons” serves as a primer for the reader regarding the electromagnetic spectrum, detailing the photon and its relationship to and of the electromagnetic spectrum of energy. What is important here is that, as noted by NASA, all these forms of electromagnetic energy

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Retrieved Text: 1. Did you know that the true nature of light has never been determined? Thomas Young, along with Arago and Fresnel,showed that a light beam, separated by a calcite prism, produces no interference fringes, only uniform illumination.Therefore the light waves must be transverse, with the planes of vibration at right angles to each other. This was discovered in 1817, yet even today light is thought to propagate as a longitudinal wave. Antenna radiation is also transverse, and the true shape of the wavefront of an electromagnetic wave is described on the waves page.
2. Max Planck's famousquantum radiation theory was based on Rayleigh's radiation equation and the assertion that tiny, discrete random energy exchanges occur between atoms, which he assumed to be "oscillators". The energy change (photon) is equal to the quantity hf, where f is the frequency and h is Planck's constant. He claimed that the energy lost radiates in the form of an electromagnetic wave. Einstein, in a later experiment of the "photoelectric effect" in which electrons are liberated from a metal surface, concluded that light radiates in the form of particles that he called "photons". The exact shape of a photon is yet to be measured, but it behaves sometimes as a particle and sometimes as a wave. Today's physicists simply say that light has "dual wave-particle" properties, without giving any reason for the effect. To truly understand electromagnetic radiation, see "The Secret of Gravity" page.
3. The secret of gravity has never before been solved. Dr. Vlasak, an electronic engineer with many years of

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Retrieved Text: Qigong, Pranic, Reiki, Yoga and other types of energy practices tap into a source fromthe bioenergy field. In this article, Instructor Don Brown reveals what every energy professional practitioner needs to know about bioenergy as it relates to biophotons.
“Recently, Sifu Cindy Cicero did which many of us engaged in chi training would love to do: Sifu Cicero was able to have her bio electromagnetic energy [chi] measured via a well-documented and innovative technique. With an open mind and lighthearted spirit, Sifu Cicero allowed the scientists at the Rhine Research Center, located on the beautiful campus of Duke University, to measure her electromagnetic output.
The text that follows introduces the Rhine Research Center and serves as a backdrop to the experiment in which Sifu Cicero participated and; provides multiple layers of detail describing electromagnetic energy and the biophotonic nature of the human being.
Established in 1927, the Rhine Research Center was Duke University’s laboratory focused on the investigation of psychic phenomena. In fact, the Rhine Research Center gave birth to the well-known Zener [ESP] cards, and helped pave the way for the rigorous field of scientific study we now call parapsychology.
Although their mission statement has broadened somewhat over the years, the Rhine center, now a standalone complex, is better poised to investigate the study of “human consciousness – its reach, its reality, its durability, its healing capacity, and its spiritual dimension”. This mission statement dovetails perfectly into the practice and charter of The International Online School of Bio-Energy Training.
As previously mentioned, Sifu Cindy Cicero had the unique and privileged

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Retrieved Text: Fee, M. S., Chu, S., Mills, A. P., Chichester, R. J., Zuckerman, D. M., Shaw, E. D., et al. (1993). Measurement of the positronium 1 3S1–2 3S1 interval by continuous-wave two-photon excitation. Physical Review A, 48(1), 192-219. doi:10.1103/PhysRevA.48.192.
Abstract: Positronium is the quasistable bound system consisting of an electron and its antiparticle, the positron. Its energy levels can be explained to a high degree of accuracy by the electromagnetic interaction, affording an ideal test of the quantum electrodynamic (QED) theory of bound systems. We have measured the 1 3S1–2 3S1 interval in positronium by Doppler-free two-photon spectroscopy to be 1 233 607 216.4±3.2 MHz. We employ continous-wave (cw) excitation to eliminate the problems inherent with pulsed laser measurements of nonlinear transitions. Positronium (Ps) atoms generated in vacuum are excited to the 2S state using cw laser light built up to 2.5 kW circulating power in a resonant Fabry-Pérot cavity. The excited-state atoms are photoionized using a pulsed laser at 532 nm, and the liberated positrons counted as the cw laser is tuned relative to a reference line in tellurium (Te2) molecular vapor. The fit of a detailed theoretical model to the measured line shape determines the Ps resonance frequency relative to the Te2 reference line. The Monte Carlo model includes details of the excitation and detection geometry, the Ps velocity distribution, and the dynamic Stark shift, and gives excellent agreement with the measured line shapes. The quoted 2.6 parts per billion (ppb) uncertainty is dominated by the measurement of the Ps line center relative to the Te2

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Retrieved Text: By Donald I. Mcree, Ph. D.
Author: Donald I. Mcree, Ph. D.
Excerpt: Properties of Microwaves Microwaves are electromagnetic waves which fall in the frequency range of approximately 30-300,000 MHz. The location of the microwave band in the electromagnetic spectrum is shown in Fig. 1. From the relation h = c/v, (where h is the wavelength of the radiation, c is the speed of light, and v is the frequency) the range of the wavelength of the radiation in free space is determined to be 1000 centimeters-to 0.1 centimeter. Microwaves are often referred to as nonionizing radiation. Using the relationship, E = hv, (where h = Planck constant = 4.135 e.v.-sec) the energy per photon of the radiation can be calculated. For the microwave portion of the electromagnetic spectrum, the energy per photon ranges from 1.24 x 10-0 1.24 x 10. e.v. Since the ionization energy for atoms is of the order of 1 e.v., it can readily be seen that microwaves cannot ionize the atom. Therefore, any interaction between microwaves and biological material would be by a mechanism other than ionization.

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Retrieved Text: I was just looking down at the person whom you quoted that accused you of misusing Planck's Law. What I find as strange is that these same people seem to think that the Stefan-Boltzman law means anything other than the emission temperature of the surface of the Earth. While Planck's law describes what the Sun's emissions are actually doing to the Earth.
The "emission" factor of the Stefan-Boltzmann law isn't even important since we know that the energy in-energy out ratio is very very close to 1. This makes the emission factor also so close to 1 as makes no difference.
There certainly seems to be a great many people who do not actually know anything but instead are arguing that someone ELSE does. Now I find that pretty silly.
1. Different photons have different amounts of energy. Planck's law tells you how much energy each photon has by factoring the photon's wavelength and the temperature of the body emitting the photon. At the same time, the reverse is used to determine if the energy level of a particular photon of a particular wavelength is sufficient to be absorbed by a particular body of a particular temperature. This ensures Planck's law adheres to the 2nd LoT.
2. Stefan-Boltzmann is derived from Planck's law by simply integrating it over all wavelengths ... which is why it is absolutely absurd for anyone to even pretend to discuss specific wavelengths or frequency bands when discussing Stefan-Boltzmann because it covers them all. Stefan-Boltzmann tells you the total radiance power, i.e. energy over time, for

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Retrieved Text: back and forth by applying a alternating electrical voltage to the mast.
are located on the far left of the spectrum and the shorter wavelength, higher frequency regions are on the far right.
locate likely fish holding areas of the river. So how does this amazing optical material work?
light that is horizontally polarized. See diagram b.
surface therefore cannot get through the polarizer and is thus eliminated.
is affectionately known as ROYGBIV.
traveled the extra distance across the diameter of the earth’s orbit.
to turn on-eighth of a rotation, the light would be reflected into the eyepiece. If too slow or too fast it wouldn’t enter the eyepiece.
Michelson received the 1907 Nobel Prize in physics for this experiment. He was the first American scientist to receive this prize.
sun to earth, and 4 years from the next nearest star Alpha Centauri. The distance light travels in a year is called a light year.
is also waves. The energy of a photon is proportional to its frequency and all the photons of a given frequency have the same amount of energy.
What is a) the frequency of a 450 nm light wave? b) how much energy would each photon have and c) what color is this wavelength?
Light particles have small amounts of energy which can be expressed as electron-volts.
How much energy does a blue light particle carry in eV’s?
light source (predicted by photon theory, E = h f)) and not the intensity of the light source (predicted by wave theory).
If each photon carries more energy it will give the electron more KE when it hits it.
work

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Retrieved Text: In the late 19th century, many physicists believed that they had made great progress in physics, and there wasn't much more that needed to be discovered. The classical physics at the time was widely accepted in the scientific community. However, by the early 20th century, physicists discovered that the laws of classical mechanics break down in the atomic world, and experiments such as the photoelectric effect completely contradict the laws of classical physics. As a result of these crises, physicists began to construct new laws of physics which would apply to the atomic world; these theories would be collectively known as quantum mechanics. Quantum mechanics, in some ways, completely changed the way physicists view the universe, and it also marked the end of the idea of a clockwork universe (the idea that the universe was predictable).
Electromagnetic radiation (ER) is a form of energy that sometimes acts like a wave, and other times acts like a particle. Visible light is a well-known example. All forms of ER have two inversely proportional properties: wavelength and frequency. Wavelength is the distance from one wave peak to the next, which can be measured in meters. Frequency is the number of wave peaks observed in a given point during a second. The unit for frequency is hertz.
The wavelength and frequency of any specific occurrence of ER determine its position on the electromagnetic spectrum.
As you can see, visible light is only a tiny fraction of the spectrum.
is the frequency. Energy is directly proportional to frequency — doubling the frequency will double the

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Retrieved Text: Extreme ultraviolet radiation (EUV or XUV) or high-energy ultraviolet radiation is electromagnetic radiation in the part of the electromagnetic spectrum spanning wavelengths from 124 nm down to 10 nm, and therefore (by the Planck–Einstein equation) having photons with energies from 10 eV up to 124 eV (corresponding to 124 nm to 10 nm respectively). EUV is naturally generated by the solar corona and artificially by plasma and synchrotron light sources. Since UVC extends to 100 nm, there is some overlap in the terms.
Its main uses are photoelectron spectroscopy, solar imaging, and lithography.
In air, EUV is the most highly absorbed component of the electromagnetic spectrum, requiring high vacuum for transmission.
Neutral atoms or condensed matter cannot emit EUV radiation. Ionization must take place first. EUV light can only be emitted by electrons which are bound to multicharged positive ions; for example, to remove an electron from a +3 charged carbon ion (three electrons already removed) requires about 65 eV. Such electrons are more tightly bound than typical valence electrons. The existence of multicharged positive ions is only possible in a hot dense plasma. Alternatively, the free electrons and ions may be generated temporarily and instantaneously by the intense electric field of a very-high-harmonic laser beam. The electrons accelerate as they return to the parent ion, releasing higher energy photons at diminished intensities, which may be in the EUV range. If the released photons constitute ionizing radiation, they will also ionize the atoms of the harmonic-generating medium, depleting the sources of higher-harmonic generation. The freed electrons escape since the

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Retrieved Text: Water is essential for life, but how can we be sure that our water is safe to drink? The ongoing Flint crisis of lead and other toxic metals in drinking water has raised alarm around the country, but new research using sound waves and lasers promises to bring some peace of mind by providing a simple option for field testing.
Matter interacts with electromagnetic waves, be they microwaves, infrared, visible light, or X-rays, in a very particular way. Thanks to the quantized nature of the allowed energy levels for the electrons in an atom, individual atoms only absorb and emit certain frequencies of light, and these frequencies define an inherent characteristic of the element that acts like a fingerprint for it. Molecules, comprised of multiple atoms, also have unique fingerprints, particularly in the infrared region of the electromagnetic spectrum.
As an example, let’s consider the simplest atom: the hydrogen atom, which has one proton in its nucleus and one electron bound to that nucleus. The electron is negatively charged and is attracted to the positively charged proton, but it is only bound to the proton in energy states located at specific distances from the nucleus, and cannot be at locations between these allowed states. Charged particles, such as electrons, interact with individual packets of electromagnetic energy—photons—which carry a certain amount of energy directly proportional to their frequency. When a photon has the same amount of energy as the difference between the lower-energy state a particle is in and an available higher-energy state, then the particle can absorb the

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Retrieved Text: The modern physics of quantum mechanics was born in 1900 when Max Planck after many unsuccessful attempts in an "act of despair" introduced a universal smallest quantum of action h=6.626×10−34Js=4.12×10−15eVs named Planck's constant in a theoretical justification of the spectrum of radiating bodies observed in experiments, based on statistics of packets of energy of size hν with ν frequency.
For many years, such an aim for me was to find the solution to the problem of the distribution of energy in the normal spectrum of radiating heat.
So there was nothing left for me but to tackle the problem from the opposite side, that of thermodynamics, in which field I felt, moreover, more confident.
For this reason, I busied myself, from then on, that is, from the day of its establishment, with the task of elucidating a true physical character for the formula, and this problem led me automatically to a consideration of the connection between entropy and probability, that is, Boltzmann's trend of ideas; until after some weeks of the most strenuous work of my life, light came into the darkness, and a new undreamed-of perspective opened up before me.
Classical physics was on loose footing with problems of wave/particle duality, but was caught completely off-guard with the discovery of the uncertainty principle.
The uncertainty principle also called the Heisenberg Uncertainty Principle, or Indeterminacy Principle, articulated (1927) by the German physicist Werner Heisenberg, that the position and the velocity of an object cannot both be measured exactly, at the same time, even in theory. The very concepts of exact position

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Retrieved Text: Do electromagnetic waves carry energy and momentum ?
Any type of particle or wave that is in motion carries momentum Electromagnetic waves like any other wave carry energy as they travel through empty space. If light didn't carry energy, it wouldn't be able to heat stuff up or generate photo current in photo cells.
Of course! Any type of particle or wave that is in motion carries momentum; either linear or angular, depending on the motion of the particle or wave.
For example, an electron would have angular momentum as it revolves around the nucleus of an atom while a photon would have linear momentum as it travels from this screen onto your retina.
Yes any type of wave under motion carries momentum and they also carry energy as they travel through empty space.
Of course! Any type of particle or wave that is in motion carries momentum Electromagnetic waves like any other wave carry energy as they travel through empty space. If light didn't carry energy, it wouldn't be able to heat stuff up or generate photo current in photo cells.
What is the annual fees of mass physics for class 12 ?
Can you add three unit vectors to get a unit vector? Does the answer change if two unit vectors are along coordinate axis? Please give example.

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Retrieved Text: This note explains the following topics: Elementary particles, Fermions and bosons, Particles and anti-particles, Scattering experiments, A role model: Quantum electrodynamics, Invariances and quantum numbers, Strong interactions, Weak interactions, Beyond the standard model.
This book includes theoretical aspects, with chapters outlining the generation model and a charged Higgs boson model as alternative scenarios to the Standard Model. An introduction is provided to postulated axion photon interactions and associated photon dispersion in magnetized media. The book concludes with a chapter tackling potential radiation hazards associated with extremely weakly interacting neutrinos if produced in copious amounts with future high-energy muon-collider facilities.
This note explains the following topics: Particles and Forces, Wave Equations and Anti Particles, The Electromagnetic Field, Perturbation Theory and Fermi�s Golden Rule, Electromagnetic Scattering of Spinless Particles, The Dirac Equation, Solutions of the Dirac Equation, The Weak Interaction, Local Gauge Invariance, Electroweak Theory.
This note explains the following topics: Elementary particles, Order of Magnitude Calculations, Reaction rates and Cross Section, The Electromagnetic Interaction, The Weak Interaction, STRANGENESS, Quark Mixing, Spontaneous Symmetry Breaking, the Higgs Scalar, Neutrino Oscillation, Neutrino Experiments and The Muon Anomaly.
This note is an introduction to the standard model of particle physics, the strong and electroweak interactions between the basic constituents of the world, quarks and leptons, via the exchange of gluons, photons and W and Z particles.
This note covers the following topics: Fundamental blocks of nature, Fundamental forces of nature, Particle decays, Interactions, Standard Model.

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Retrieved Text: Abstract: I develop a firm number for the local wavelength of the photon, show how it is created by the spin of the photon, and how this local spin is stretched by the linear motion into the wavelength we see and measure. I prove that the transform from the local wavelength to the measured wavelength is c2, showing why this term is found in the famous equation E = mc2.
In previous papers I have shown that photons have a number of stacked spins, explaining the mysteries of superposition and so on. But here I will look at the linear motion of photons. I will study how the measured wavelength is caused by the wavelength of the spins, and how different colors are created.
Before we get into that, I would like to give credit to Descartes, who knew that color was caused by photon spins in the early 1600's. I believe he made this proposal in Dioptrique, around 1638. This was before Newton's corpuscles, so the fact that Descartes was able to intuit an answer so close to correct at that time is extremely laudable. If I remember correctly, Descartes got the energies reversed from red to blue, but connecting color to spin was a masterstroke in itself. We will see that color is due to the size of the photon, which is more a matter of radius than spin velocity, but the two are inextricably linked. It is spin collisions that cause the spin radius, so we would obviously have no spin radius without spin. Since

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Retrieved Text: Planck’s constant is a number, it describes the size of the energy packets that are contained within light. These packets of energy are called photons. Planck’s constant is given the symbol h and the value of h is equal to 6.63 x 10-34⁻³⁴ J\se.
While Planck’s constant can now be found in many equations, the equation that defines Planck’s constant is called the Planck-Einstein relation. Max Planck theorized that energy was transferred in chunks is known as quanta, equal to hυ. The variable h is a constant equal to 6.63 x 10-34⁻³⁴ J\sec based on International system of units and the variable υ represents the frequency in Hz. This equation allows us to calculate the energy of photons, given their frequency.
H = Plank’s Constant = 6.63 x 10-34⁻³⁴ J\sec = 4.136 x 10⁻¹⁵ eV.
If the wavelength is known, we can calculate the energy by using the wave equation to calculate the frequency and then apply Planck’s equation to find the energy.
Planck’s law: It states that electromagnetic radiation from heated bodies is not emitted as a continuous flow but is made up of discrete units or quanta of energy, the size of which involve a fundamental physical constant.
Problem: A Green light has a wavelength of 500nm. Determine the energy for the Green light in Joules?
∴ Frequency (υ) = 0.6 x 10⁻³/ sec.
∴ E = 3.98 x 10⁻³⁸ J/ Photon.

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Retrieved Text: Throughout our history, many of our greatest scientific progresses have come from what are called, thought-experiments. Now, I, being extremely thoughtful like all the time, participate in a lot of thought experiments that may or may not have bearing on the world at all, but it's really fun to think about the world differently than what we perceive it to be. So, i think I should partake in a thought experiment with all of you guys, just see what happens.
Okay, a photon is a particle of light that is derived off of a reaction from an atom. This can be many things, but for this case say the Sun makes a photon. This photon moves in a predictable wave that travels at a high speed in a straight line until pushed or pulled by a force or reflected off of an opaque surface. Say this photon does not get reflected and it goes out into the universe forever and ever, unstopped.
3. the proton collapses on itself causing a giant reaction, possibly making more protons in a chain reaction, sparking the question, where did the protons come from?
if light stopped moving, would it esist?
do you keep meaning to say photon and not proton?
If I understand entrophy correctly, and I don't claim to, then the photon would not surive the excelleration process. Thus it would be completely obliterated and it's energy nullified.
As I understand it we are talking about a proton, and flat out, if no other force acts on that proton it will continue on forever and

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Retrieved Text: Which makes more sense: that photons [and other quantum objects] are neither waves nor particles or that they both waves and particles?
I found the following statement in 'The Feynmann Lectures in Physics', Volume 1, page 2-7: '...things which we used to consider as waves also behave like particles, and particles behave like waves; in fact, everything behaves the same way. There is no distinction between a particle and a wave. So, quantum mechanics unifies the idea of the field and its waves, and the particles, all into one.' Feynmann goes on to explain that the frequency of the field (e.g., light; PZ) and the ability of the equipment we use to measure the frequency of the field determine whether the field looks to us like a particle or a wave.
Answered by: Philip Zell, Ph.D. Physics, ACT, Inc.
where 'E' stands for energy, 'h' stands for planks contant which is equal to ~6.63608 * 10-34 joules/sec, 'v' stands for frequency of wave, and 'n' represents a positive integer.
Physicists interpreted the Planks statement as the 'quantum theory' which states that the energy packets are of fixed amount i.e. quantised.
Later in 1905, Einstein presented his 'photon theory' carrying the Plank's idea of packeted energy. Einstein proposed that the radiation is in fact particulate. Einstein further presented the properties of 'blackbody radiation' and 'photoelectric effect' which proved that electromagnetic radiation which is 'wavelike'(shows properties of refraction and defraction) also behaves as 'particlelike'.
here 'h' represents the plank's contant, 'm' represents the mass of the particle, and 'v' represents the velocity of the

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Retrieved Text: The wave theory of light, which Maxwell’s equations captured so well, became the dominant light theory in the 1800s (surpassing Newton’s corpuscular theory, which had failed in a number of situations). The first major challenge to the theory came in explaining thermal radiation, which is the type of electromagnetic radiation emitted by objects because of their temperature.
An apparatus can be set up to detect the radiation from an object maintained at temperature T1. (Since a warm body gives off radiation in all directions, some sort of shielding must be put in place so the radiation being examined is in a narrow beam.) Placing a dispersive medium (i.e. a prism) between the body and the detector, the wavelengths (λ) of the radiation disperse at an angle (θ). The detector, since it’s not a geometric point, measures a range delta-theta which corresponds to a range delta-λ, though in an ideal set-up this range is relatively small.
The experiment outlined above detects dI, and therefore R(λ) can be determined for any desired wavelength.
The total intensity radiated over all wavelengths (i.e. the area under the R(λ) curve) increases as the temperature increases.
The value of the wavelength λmax at which the radiancy reaches its maximum decreases as the temperature increases.
The above description involved a bit of cheating. Light is reflected off objects, so the experiment described runs into the problem of what is actually being tested. To simplify the situation, scientists looked at a blackbody, which is to say an object that does not reflect any light.
Consider a metal box with a

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Retrieved Text: The most important part of an LED is the semi-conductor chip located in the center of the light source. The chip has two regions separated by a junction. The p region is dominated by positive electric charges and the n region is dominated by negative electric charges. The junction acts as a barrier to the flow of electrons between the p and the n regions. When sufficient voltage is applied to the semi-conductor chip, the electrons are able to cross the junction into the p region.
Each time an electron recombines with a positive charge, electric potential energy is converted into electromagnetic energy. For each recombination of a negative and a positive charge, a quantum of electromagnetic energy is emitted in the form of a photon of light. This photon has a frequency determined by the characteristics of the semiconductor material (usually a combination of the chemical elements gallium, arsenic, and phosphorus). LEDs that emit different colors are made of different semiconductor materials. Said simply, LEDs are tiny “bulbs” fit into an electrical circuit. However, unlike ordinary incandescent bulbs, they don’t have a filament. LEDs are illuminated solely by the movement of electrons in a semiconductor material, making them energy efficient and extremely resilient over long periods of time.
LEDs don’t have a filament to burn out or break; therefore, they last much longer than conventional bulbs. Given that a very small semiconductor chip runs an LED, they are very durable and tend to last many thousands of hours. Moreover, LEDs are “instant on,” much like halogen lamps,

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Retrieved Text: If I asked you to picture a photon, an electromagnetic wave, I’d expect the image that popped into your head to look something like the one below, with the characteristic intertwined sine curves of the electric and magnetic field vectors.
This model of electromagnetic radiation dates back to the work of James Clerk Maxwell, whose differential equations laid the groundwork for the pre-Einsteinian understanding of electricity and magnetism, and to this day, this is still how most students first learn to think about the quantum of light—as a plane-polarized wave, composed of perpendicular 2D components.
Pictured this way, however, the photon behaves unlike any familiar 3D system, with its components shrinking out of existence before popping back in, upside-down. As for analogies, waves on the surface of a pond fall short by a full dimension, leaving the student wondering which way is “up”, and what provides the restoring force equivalent to gravity. Once a student understands the derivative relationship between electricity and magnetism—that one is induced by a change in the other—the nature of light starts to make more sense mathematically, but this doesn’t make it any more intuitively palatable, and accepting the peculiar undulations of the sine wave as a real, physical thing can be a difficult stumbling block for people to surmount. But there’s an easier, more fundamental way to think of photons—it’s surprising at first, but ultimately a great relief to learn that the plane-polarized electromagnetic wave pictured above is not one photon, but two! In truth, neither part of the photon ever vanishes, or

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Retrieved Text: Photon emission processes have corresponding absorption processes. We will mainly consider X-ray absorption.
Take an astronomical source at distance L from the observer.
The fraction of volume, dV, which h is blocked by the presence of element Z can also be thought of as the probability that a photon from the sourceis absorbed in volume dV.
Integrating over length from source.
Including all elements in the line of sight:.
Where nH is the interstellar hydrogen number density, and NH is the number of H – atoms per m2. Column density is measured from the 21 cm atomic hydrogen line but there is a factor of 2 uncertainty due to e.g. wide beams. Also the contribution to the column from molecular hydrogen is unknown since it is much harder to measure; it is believed to follow the same distribution of atomic hydrogen.
These derivations assume that the ratio of nZ to nH is constant along the path, while nH varies with distance from the observer.
Photoionization leads to recombination of the removed electron, thus photoionization removes X-ray photons – also extreme UV photons – and dominates in these bands.
The two forms of electron scattering, Thomson scattering and Compton scattering, remove photons from the line of sight. In Thomson scattering, the photon energy is much lower than the rest mass of the electron and is just deflected, while in Compton scattering, the photon effectively transfers some of its energy to the electron, thus light is absorbed.
At very high energies, photons can collide with ambient photons and form an electron-positron pair, i.e. photon energy is lost

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Retrieved Text: measuring it, and using it.
we creatures made of matter need methods of interacting with light.
but until now, we really haven't considered how.
Light production falls into two major categories: incandescence and luminescence.
Incandescence is how filament light bulbs produce light.
emitting more and more light as the temperature increases.
created by the intense vibrations of atoms and electrons at high temperatures.
the oscillation of atoms in objects creates light waves.
be wrapped up in a neat little bundle we call a photon.
which are sometimes called cold body radiation.
electron orbits move in orbits around the nucleus.
it emits or absorbs a photon of specific energy to do this.
There are many subcategories of luminescent processes.
which we can't see into visible light.
and triboluminescence produces light when we chew on hard candies like lifesavers.
let's make sure we can measure its properties.
When we want to take a measurement of light, what are we measuring?
at just under three times 10 to the eight meters per second.
the frequency, or the energy that the photon packets carry.
A typical red laser emits a beam of photons with a wavelength of 650 nanometers.
or even in terms of the photon energy, 1.9 electron volts.
one of many will come across in this course.
single electron moving across an electric potential difference of 1 volt.
1.6 times 10 to the minus 19 Joules.
The naming and labeling of light can be confusing.
and frequency can all be considered as equivalent ways to describe light.
characterized by its frequency, say 102.9 megahertz.
between 400 and 700 nanometers.
that allow you to determine the other quantities.
the speed of light c. Let's double check the values

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Retrieved Text: A stationary atom sees the laser neither red- nor blue-​shifted and does not absorb the photon.
An atom moving away from the laser sees it red-​shifted and does not absorb the photon.
An atom moving towards the laser sees it blue-​shifted and absorbs the photon, slowing the atom.
The photon excites the atom, moving an electron to a higher quantum state.
The atom re-emits a photon. As its direction is random, there is no net change in momentum over many atoms.
Doppler cooling is a mechanism that can be used to trap and slow the motion of atoms to cool a substance. The term is sometimes used synonymously with laser cooling, though laser cooling includes other techniques.
Doppler cooling was simultaneously proposed by two groups in 1975, the first being David J. Wineland and Hans Georg Dehmelt and the second being Theodor W. Hänsch and Arthur Leonard Schawlow. It was first demonstrated by Wineland, Drullinger, and Walls in 1978 and shortly afterwards by Neuhauser, Hohenstatt, Toschek and Dehmelt. One conceptually simple form of Doppler cooling is referred to as optical molasses, since the dissipative optical force resembles the viscous drag on a body moving through molasses. Steven Chu, Claude Cohen-Tannoudji and William D. Phillips were awarded the 1997 Nobel Prize in Physics for their work in laser cooling and atom trapping.
Doppler cooling involves light whose frequency is tuned slightly below an electronic transition in an atom. Because the light is detuned to the "red" (i.e. at lower frequency) of the transition, the atoms will absorb more photons if they move towards the

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Retrieved Text: Intended principally for students in engineering and the physical sciences as a continuation of PHYSICS 152L. Topics include: mechanics from a microscopic perspective, the atomic nature of matter, energy, energy quantization, entropy, the kinetic theory of gases, the efficiency of engines, electromagnetic radiation, the photon nature of light, physical optics and interference, waves and particles, applications of wave mechanics. Not open to students having credit for PHYSICS 142L or 162L. Prerequisites: PHYSICS 152L and MATH 212 or the equivalents. One course.

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======= Instance Index 1243 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are Bill or Will ):

In electromagnetic waves with higher frequencies, photons have more energy.


Will analyzes the photon energy in an electromagnetic wave with a high frequency. Bill analyzes the photon energy in an electromagnetic wave with a low frequency. Bill or Will's wave has more photon energy?

Target Text: Will

#### Retrieved Documents ####

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Retrieved Text: antenna, even though the antennas may be miles apart.
, which we will study later this quarter.
In the case of a sine wave, we associate a wavelength with a given frequency.
crest of the wave shown in Figure 2.3 above or below its midpoint.
relation given by Equation 2.2.
expressed in 1/seconds, to which we assign the name Hertz (Hz).
describe electromagnetic radiation as sine waves of a given wavelength and frequency.
meters per second, the speed of light.
refraction for some common materials.
index of refraction of light in a diamond?
The amount that light is refracted depends on the frequency of the light wave.
radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.
the longest wavelengths and lowest frequencies.
generator and receiver will be demonstrated in the classroom.
the infrared portion of the spectrum.
separate white light into the colors of the visible spectrum.
induce fluorescence and can cause tanning in human skin.
ray photographs can show bone structure and assist the medical profession in diagnosis.
nuclear reactions and will be discussed further in the period on nuclear energy.
relation shown in Equation 2.4.
indication that we still do not have a full understanding of this phenomenon.
b) How much energy does each photon of this radiant energy have?
photon energy for radiant energy.
radiant energy. This energy is associated with an electromagnetic field.
light and is given the symbol c.
2.2:Radiant energy can be thought of as a wave with a wavelength and frequency.
As light passes from one medium to another it is refracted, or bent.
index of refraction, n, of the material.
infrared radiation, visible light, ultraviolet light, X–rays, and gamma rays.
e) All of the above travel at

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Retrieved Text: With the development of Photoelectric effect, Crompton’s effect and Bohr’s model of atom, the idea of light or in fact radiations in general, being composed of particles or discrete Quanta was gaining wide popularity.
However, the very established Huygen’s Principle and the results of Young’s double slit experiments made it very clear that light was wave and not a flow particles.
The striking interference pattern observed by passing light through double slits was definitely a result of the wave nature of light. This again gave rise to the controversy of nature of light. In 1704 Newton had also suggested the particle nature of light by his corpuscular theory.
Where, h is Planck constant and p = mv, v is velocity of the body.
Thus due the huge mass of an elephant it has a very significant momentum and hence a very small wavelength, which we are unable to notice. However small particles such as electrons, etc. have very small mass and hence very noticeable wavelength or wave nature. This theory of de Broglie also helps us to explain the discrete existence of orbits in Bohr’s model of atom. An electron will exist in an orbit if its length is equal to integral multiple of its natural wavelength, if it is unable to complete its wavelength then that orbit will not exist.
Further developments by Davisson and Germer of electron diffraction from a crystal and a similar interference pattern obtained after bombarding a double slit with electrons had strengthen de Broglie’s matter wave theory or the wave particle duality theory.
In the photoelectric

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Retrieved Text: In his very first paper published in 1905 Einstein establishes the concept of “energy quanta” or “light quanta”. The manifestation of light quantum (photon) becomes more pronounced as the frequency of radiation increases.
In his paper Einstein analyzes the work done by Wien and Planck on Black Body radiation [see Black-body radiation (Notes)] and makes the following fundamental observations.
According to Maxwell’s theory, the energy must be considered to be a continuous function in space for all purely electromagnetic phenomena, thus also for light.
According to Kinetic Theory of gases, the energy in a volume can be written as a sum of energy of a finite number of particles localized in space, which move without being divided.
The classical treatment of energy as a continuous function in space fails to predict the energy spectrum observed for the black body radiation.
Max Planck’s postulate, “energy is proportional to the frequency of radiation” completely predicts the energy spectrum observed for the black body radiation.
Planck’s equation provides the classical results for low frequencies, showing that radiation energy is a continuous function in space at low frequencies only.
Using Wein’s law that matches experimental observations of black-body radiation at high frequencies, Einstein proves the energy behavior of radiation to be particle-like. From this arises Einstein’s proposal of “energy quanta” or “light quanta”.
Einstein’s demonstrates that the use of “statistical probability” by Boltzmann is compatible with the principles of physics, and they can be used to estimate the magnitude of such energy quanta.
The idea of energy quanta is compatible with the observations made in photoluminescence resulting in the

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Retrieved Text: It was subsequently recognised that a whole spectrum of electromagnetic radiation exists, from the short wavelength gamma-rays and X-rays at one extreme, through the more familiar regions of ultraviolet radiation, visible light and infrared radiation, to the long wavelength phenomena of microwaves and radio waves at the other.
The wavelength and frequency of each type of electromagnetic radiation are related by the simple equation: wavelength x frequency = speed of light, about 300,000 km/s.
This recognition of light as a wave phenomenon had in fact overturned two centuries of belief, dating back to work by Isaac Newton, that light was composed of a stream of particles.
It was observed that when light fell on a metal surface, electrons could be emitted by the metal.
Changing the intensity of the light caused the number of electrons emitted to change, but the electrons’ range of energies remained the same.
Decreasing the wavelength of the light, however, caused the electrons to be emitted with a higher maximum energy. Conversely, increasing the wavelength of the light beyond a particular cut-off value (specific to each metal), caused the emission of electrons to cease.
The explanation was that light interacts with matter as if it is composed of a stream of particles, now called photons. Each photon carries a specific amount of energy, which is directly related to the frequency used to characterise the propagation of light by the relation: energy of photon = Planck’s constant x frequency.
So light, and all other electromagnetic radiation, is now recognised as something rather strange: it propagates as if it is a

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Retrieved Text: The Photon Band, also called the Photon Belt, or Manasic Ring, is an immense region of space, 760 billion mile wide. It is a toroidal, or ring shaped field of energy, giving out intense electromagnetic radiation. It is made up of Photons, which are defined as the smallest divisible unit of light energy.
When astronomers first discovered it, they thought it was an unusual nebula, a vast cloud of gas and dust and they called it the “Golden Nebula”.
The Photon Band encircles the Pleiades Star Cluster at a right angle to its orbital planes. Our solar system is the 8th star in the Pleiades star group, orbiting Alcyone, the central sun of the Pleiades.
Our solar system completes this journey once in every 26 000 years. During that time, it is in the Photon Band twice, spending 2000 years in it each time. The 10 500 years out of the Photon Band is referred to as the “Galactic Night”.
Being in the Photon Band is a spiritual experience. The Photon energy transforms and transmutes, alters consciousness, giving opportunities for both spiritual and technological developments.
It was discovered in 1961 by means of satellite born instrumentation. In the early 1980’s there was a radio announcement that our solar system will collide with an electromagnetic cloud in the not too distant future.
Currently, Mainstream Science proclaims that this is only a New Age belief. Information on it is being suppressed. Astronomers who discussed the Photon Band lost their jobs, or have been denied access to equipment required to study it.
Yet, government scientists have

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Retrieved Text: Explain what the electromagnetic spectrum is and how scientists use it.
So far we have learned about the atom, the phenomenon of radioactivity, and we have looked at both nuclear reactions and X-ray generation. We already know that X- and gamma rays differ only in their source of origin or how they are generated. There are, however, very distinct characteristics associated with these energy forms. Two key points to remember about the characteristics of radiation are that X- and gamma rays are not bits of matter, they are electromagnetic wave forms possessing no charge and no mass, and they can be characterized by frequency, wavelength, and velocity. Let's take a closer look at the characteristics of these wave forms so that we may better understand the nature of them.
X- and gamma rays are part of what scientists refer to as the electromagnetic spectrum. They are waveforms that are part of a family in which some of the relatives are very familiar to us, such as light rays, infrared heat rays, and radio waves. However, X- and gamma rays cannot been seen, felt, or heard. In other words, our normal senses cannot detect them. Since X- and gamma rays have no mass and no electrical charge, they are not influenced by electrical and magnetic fields and will travel in straight lines. Continued research over the years since Roentgens discovery indicated that the radiation possesses a dual character. Acting somewhat like a particle at times and like a wave at other times. The name that has been given to

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Retrieved Text: As scientific discovery has advanced in the world of quantum physics, so has our understanding of chi. More specifically: whereas our foundational proposition is built around the concept that chi is electromagnetic energy that is composed of the quanta, we now have a greater specificity regarding the quantum energy we associate with chi. With that information, we are better able to engage, develop and manipulate the energy to achieve desired results, on demand and on command, all the while minimizing negative side effects that adversely impact the practitioners and those with whom they come in contact.
As noted above, we begin first with electromagnetic energy [radiation]. The electromagnetic spectrum of radiation encompasses all forms of energy. To that end, it is Universal in kind, and specific by type. This is to say that electromagnetic energy permeates the Universe, flowing into and through every known [and as yet to be discovered] object on some level. Depending on the frequency or wavelength, the electromagnetic energy takes a specific form, be it: X-ray; radio wave; microwave or; visible light. For example, electromagnetic energy that falls within the “ultraviolet” range cannot penetrate the Earth’s atmosphere [ozone layer]. Radio waves, conversely, travel across and throughout the known Universe with little to no impediments.
The article “Energy Healing and the science of Bio-Photons” serves as a primer for the reader regarding the electromagnetic spectrum, detailing the photon and its relationship to and of the electromagnetic spectrum of energy. What is important here is that, as noted by NASA, all these forms of electromagnetic energy

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Retrieved Text: 1. Did you know that the true nature of light has never been determined? Thomas Young, along with Arago and Fresnel,showed that a light beam, separated by a calcite prism, produces no interference fringes, only uniform illumination.Therefore the light waves must be transverse, with the planes of vibration at right angles to each other. This was discovered in 1817, yet even today light is thought to propagate as a longitudinal wave. Antenna radiation is also transverse, and the true shape of the wavefront of an electromagnetic wave is described on the waves page.
2. Max Planck's famousquantum radiation theory was based on Rayleigh's radiation equation and the assertion that tiny, discrete random energy exchanges occur between atoms, which he assumed to be "oscillators". The energy change (photon) is equal to the quantity hf, where f is the frequency and h is Planck's constant. He claimed that the energy lost radiates in the form of an electromagnetic wave. Einstein, in a later experiment of the "photoelectric effect" in which electrons are liberated from a metal surface, concluded that light radiates in the form of particles that he called "photons". The exact shape of a photon is yet to be measured, but it behaves sometimes as a particle and sometimes as a wave. Today's physicists simply say that light has "dual wave-particle" properties, without giving any reason for the effect. To truly understand electromagnetic radiation, see "The Secret of Gravity" page.
3. The secret of gravity has never before been solved. Dr. Vlasak, an electronic engineer with many years of

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Retrieved Text: Qigong, Pranic, Reiki, Yoga and other types of energy practices tap into a source fromthe bioenergy field. In this article, Instructor Don Brown reveals what every energy professional practitioner needs to know about bioenergy as it relates to biophotons.
“Recently, Sifu Cindy Cicero did which many of us engaged in chi training would love to do: Sifu Cicero was able to have her bio electromagnetic energy [chi] measured via a well-documented and innovative technique. With an open mind and lighthearted spirit, Sifu Cicero allowed the scientists at the Rhine Research Center, located on the beautiful campus of Duke University, to measure her electromagnetic output.
The text that follows introduces the Rhine Research Center and serves as a backdrop to the experiment in which Sifu Cicero participated and; provides multiple layers of detail describing electromagnetic energy and the biophotonic nature of the human being.
Established in 1927, the Rhine Research Center was Duke University’s laboratory focused on the investigation of psychic phenomena. In fact, the Rhine Research Center gave birth to the well-known Zener [ESP] cards, and helped pave the way for the rigorous field of scientific study we now call parapsychology.
Although their mission statement has broadened somewhat over the years, the Rhine center, now a standalone complex, is better poised to investigate the study of “human consciousness – its reach, its reality, its durability, its healing capacity, and its spiritual dimension”. This mission statement dovetails perfectly into the practice and charter of The International Online School of Bio-Energy Training.
As previously mentioned, Sifu Cindy Cicero had the unique and privileged

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Retrieved Text: Fee, M. S., Chu, S., Mills, A. P., Chichester, R. J., Zuckerman, D. M., Shaw, E. D., et al. (1993). Measurement of the positronium 1 3S1–2 3S1 interval by continuous-wave two-photon excitation. Physical Review A, 48(1), 192-219. doi:10.1103/PhysRevA.48.192.
Abstract: Positronium is the quasistable bound system consisting of an electron and its antiparticle, the positron. Its energy levels can be explained to a high degree of accuracy by the electromagnetic interaction, affording an ideal test of the quantum electrodynamic (QED) theory of bound systems. We have measured the 1 3S1–2 3S1 interval in positronium by Doppler-free two-photon spectroscopy to be 1 233 607 216.4±3.2 MHz. We employ continous-wave (cw) excitation to eliminate the problems inherent with pulsed laser measurements of nonlinear transitions. Positronium (Ps) atoms generated in vacuum are excited to the 2S state using cw laser light built up to 2.5 kW circulating power in a resonant Fabry-Pérot cavity. The excited-state atoms are photoionized using a pulsed laser at 532 nm, and the liberated positrons counted as the cw laser is tuned relative to a reference line in tellurium (Te2) molecular vapor. The fit of a detailed theoretical model to the measured line shape determines the Ps resonance frequency relative to the Te2 reference line. The Monte Carlo model includes details of the excitation and detection geometry, the Ps velocity distribution, and the dynamic Stark shift, and gives excellent agreement with the measured line shapes. The quoted 2.6 parts per billion (ppb) uncertainty is dominated by the measurement of the Ps line center relative to the Te2

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Retrieved Text: By Donald I. Mcree, Ph. D.
Author: Donald I. Mcree, Ph. D.
Excerpt: Properties of Microwaves Microwaves are electromagnetic waves which fall in the frequency range of approximately 30-300,000 MHz. The location of the microwave band in the electromagnetic spectrum is shown in Fig. 1. From the relation h = c/v, (where h is the wavelength of the radiation, c is the speed of light, and v is the frequency) the range of the wavelength of the radiation in free space is determined to be 1000 centimeters-to 0.1 centimeter. Microwaves are often referred to as nonionizing radiation. Using the relationship, E = hv, (where h = Planck constant = 4.135 e.v.-sec) the energy per photon of the radiation can be calculated. For the microwave portion of the electromagnetic spectrum, the energy per photon ranges from 1.24 x 10-0 1.24 x 10. e.v. Since the ionization energy for atoms is of the order of 1 e.v., it can readily be seen that microwaves cannot ionize the atom. Therefore, any interaction between microwaves and biological material would be by a mechanism other than ionization.

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Retrieved Text: I was just looking down at the person whom you quoted that accused you of misusing Planck's Law. What I find as strange is that these same people seem to think that the Stefan-Boltzman law means anything other than the emission temperature of the surface of the Earth. While Planck's law describes what the Sun's emissions are actually doing to the Earth.
The "emission" factor of the Stefan-Boltzmann law isn't even important since we know that the energy in-energy out ratio is very very close to 1. This makes the emission factor also so close to 1 as makes no difference.
There certainly seems to be a great many people who do not actually know anything but instead are arguing that someone ELSE does. Now I find that pretty silly.
1. Different photons have different amounts of energy. Planck's law tells you how much energy each photon has by factoring the photon's wavelength and the temperature of the body emitting the photon. At the same time, the reverse is used to determine if the energy level of a particular photon of a particular wavelength is sufficient to be absorbed by a particular body of a particular temperature. This ensures Planck's law adheres to the 2nd LoT.
2. Stefan-Boltzmann is derived from Planck's law by simply integrating it over all wavelengths ... which is why it is absolutely absurd for anyone to even pretend to discuss specific wavelengths or frequency bands when discussing Stefan-Boltzmann because it covers them all. Stefan-Boltzmann tells you the total radiance power, i.e. energy over time, for

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Retrieved Text: back and forth by applying a alternating electrical voltage to the mast.
are located on the far left of the spectrum and the shorter wavelength, higher frequency regions are on the far right.
locate likely fish holding areas of the river. So how does this amazing optical material work?
light that is horizontally polarized. See diagram b.
surface therefore cannot get through the polarizer and is thus eliminated.
is affectionately known as ROYGBIV.
traveled the extra distance across the diameter of the earth’s orbit.
to turn on-eighth of a rotation, the light would be reflected into the eyepiece. If too slow or too fast it wouldn’t enter the eyepiece.
Michelson received the 1907 Nobel Prize in physics for this experiment. He was the first American scientist to receive this prize.
sun to earth, and 4 years from the next nearest star Alpha Centauri. The distance light travels in a year is called a light year.
is also waves. The energy of a photon is proportional to its frequency and all the photons of a given frequency have the same amount of energy.
What is a) the frequency of a 450 nm light wave? b) how much energy would each photon have and c) what color is this wavelength?
Light particles have small amounts of energy which can be expressed as electron-volts.
How much energy does a blue light particle carry in eV’s?
light source (predicted by photon theory, E = h f)) and not the intensity of the light source (predicted by wave theory).
If each photon carries more energy it will give the electron more KE when it hits it.
work

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Retrieved Text: In the late 19th century, many physicists believed that they had made great progress in physics, and there wasn't much more that needed to be discovered. The classical physics at the time was widely accepted in the scientific community. However, by the early 20th century, physicists discovered that the laws of classical mechanics break down in the atomic world, and experiments such as the photoelectric effect completely contradict the laws of classical physics. As a result of these crises, physicists began to construct new laws of physics which would apply to the atomic world; these theories would be collectively known as quantum mechanics. Quantum mechanics, in some ways, completely changed the way physicists view the universe, and it also marked the end of the idea of a clockwork universe (the idea that the universe was predictable).
Electromagnetic radiation (ER) is a form of energy that sometimes acts like a wave, and other times acts like a particle. Visible light is a well-known example. All forms of ER have two inversely proportional properties: wavelength and frequency. Wavelength is the distance from one wave peak to the next, which can be measured in meters. Frequency is the number of wave peaks observed in a given point during a second. The unit for frequency is hertz.
The wavelength and frequency of any specific occurrence of ER determine its position on the electromagnetic spectrum.
As you can see, visible light is only a tiny fraction of the spectrum.
is the frequency. Energy is directly proportional to frequency — doubling the frequency will double the

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Retrieved Text: Extreme ultraviolet radiation (EUV or XUV) or high-energy ultraviolet radiation is electromagnetic radiation in the part of the electromagnetic spectrum spanning wavelengths from 124 nm down to 10 nm, and therefore (by the Planck–Einstein equation) having photons with energies from 10 eV up to 124 eV (corresponding to 124 nm to 10 nm respectively). EUV is naturally generated by the solar corona and artificially by plasma and synchrotron light sources. Since UVC extends to 100 nm, there is some overlap in the terms.
Its main uses are photoelectron spectroscopy, solar imaging, and lithography.
In air, EUV is the most highly absorbed component of the electromagnetic spectrum, requiring high vacuum for transmission.
Neutral atoms or condensed matter cannot emit EUV radiation. Ionization must take place first. EUV light can only be emitted by electrons which are bound to multicharged positive ions; for example, to remove an electron from a +3 charged carbon ion (three electrons already removed) requires about 65 eV. Such electrons are more tightly bound than typical valence electrons. The existence of multicharged positive ions is only possible in a hot dense plasma. Alternatively, the free electrons and ions may be generated temporarily and instantaneously by the intense electric field of a very-high-harmonic laser beam. The electrons accelerate as they return to the parent ion, releasing higher energy photons at diminished intensities, which may be in the EUV range. If the released photons constitute ionizing radiation, they will also ionize the atoms of the harmonic-generating medium, depleting the sources of higher-harmonic generation. The freed electrons escape since the

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Retrieved Text: Water is essential for life, but how can we be sure that our water is safe to drink? The ongoing Flint crisis of lead and other toxic metals in drinking water has raised alarm around the country, but new research using sound waves and lasers promises to bring some peace of mind by providing a simple option for field testing.
Matter interacts with electromagnetic waves, be they microwaves, infrared, visible light, or X-rays, in a very particular way. Thanks to the quantized nature of the allowed energy levels for the electrons in an atom, individual atoms only absorb and emit certain frequencies of light, and these frequencies define an inherent characteristic of the element that acts like a fingerprint for it. Molecules, comprised of multiple atoms, also have unique fingerprints, particularly in the infrared region of the electromagnetic spectrum.
As an example, let’s consider the simplest atom: the hydrogen atom, which has one proton in its nucleus and one electron bound to that nucleus. The electron is negatively charged and is attracted to the positively charged proton, but it is only bound to the proton in energy states located at specific distances from the nucleus, and cannot be at locations between these allowed states. Charged particles, such as electrons, interact with individual packets of electromagnetic energy—photons—which carry a certain amount of energy directly proportional to their frequency. When a photon has the same amount of energy as the difference between the lower-energy state a particle is in and an available higher-energy state, then the particle can absorb the

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Retrieved Text: The modern physics of quantum mechanics was born in 1900 when Max Planck after many unsuccessful attempts in an "act of despair" introduced a universal smallest quantum of action h=6.626×10−34Js=4.12×10−15eVs named Planck's constant in a theoretical justification of the spectrum of radiating bodies observed in experiments, based on statistics of packets of energy of size hν with ν frequency.
For many years, such an aim for me was to find the solution to the problem of the distribution of energy in the normal spectrum of radiating heat.
So there was nothing left for me but to tackle the problem from the opposite side, that of thermodynamics, in which field I felt, moreover, more confident.
For this reason, I busied myself, from then on, that is, from the day of its establishment, with the task of elucidating a true physical character for the formula, and this problem led me automatically to a consideration of the connection between entropy and probability, that is, Boltzmann's trend of ideas; until after some weeks of the most strenuous work of my life, light came into the darkness, and a new undreamed-of perspective opened up before me.
Classical physics was on loose footing with problems of wave/particle duality, but was caught completely off-guard with the discovery of the uncertainty principle.
The uncertainty principle also called the Heisenberg Uncertainty Principle, or Indeterminacy Principle, articulated (1927) by the German physicist Werner Heisenberg, that the position and the velocity of an object cannot both be measured exactly, at the same time, even in theory. The very concepts of exact position

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Retrieved Text: Do electromagnetic waves carry energy and momentum ?
Any type of particle or wave that is in motion carries momentum Electromagnetic waves like any other wave carry energy as they travel through empty space. If light didn't carry energy, it wouldn't be able to heat stuff up or generate photo current in photo cells.
Of course! Any type of particle or wave that is in motion carries momentum; either linear or angular, depending on the motion of the particle or wave.
For example, an electron would have angular momentum as it revolves around the nucleus of an atom while a photon would have linear momentum as it travels from this screen onto your retina.
Yes any type of wave under motion carries momentum and they also carry energy as they travel through empty space.
Of course! Any type of particle or wave that is in motion carries momentum Electromagnetic waves like any other wave carry energy as they travel through empty space. If light didn't carry energy, it wouldn't be able to heat stuff up or generate photo current in photo cells.
What is the annual fees of mass physics for class 12 ?
Can you add three unit vectors to get a unit vector? Does the answer change if two unit vectors are along coordinate axis? Please give example.

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Retrieved Text: This note explains the following topics: Elementary particles, Fermions and bosons, Particles and anti-particles, Scattering experiments, A role model: Quantum electrodynamics, Invariances and quantum numbers, Strong interactions, Weak interactions, Beyond the standard model.
This book includes theoretical aspects, with chapters outlining the generation model and a charged Higgs boson model as alternative scenarios to the Standard Model. An introduction is provided to postulated axion photon interactions and associated photon dispersion in magnetized media. The book concludes with a chapter tackling potential radiation hazards associated with extremely weakly interacting neutrinos if produced in copious amounts with future high-energy muon-collider facilities.
This note explains the following topics: Particles and Forces, Wave Equations and Anti Particles, The Electromagnetic Field, Perturbation Theory and Fermi�s Golden Rule, Electromagnetic Scattering of Spinless Particles, The Dirac Equation, Solutions of the Dirac Equation, The Weak Interaction, Local Gauge Invariance, Electroweak Theory.
This note explains the following topics: Elementary particles, Order of Magnitude Calculations, Reaction rates and Cross Section, The Electromagnetic Interaction, The Weak Interaction, STRANGENESS, Quark Mixing, Spontaneous Symmetry Breaking, the Higgs Scalar, Neutrino Oscillation, Neutrino Experiments and The Muon Anomaly.
This note is an introduction to the standard model of particle physics, the strong and electroweak interactions between the basic constituents of the world, quarks and leptons, via the exchange of gluons, photons and W and Z particles.
This note covers the following topics: Fundamental blocks of nature, Fundamental forces of nature, Particle decays, Interactions, Standard Model.

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Rank: 19
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Retrieved Text: Abstract: I develop a firm number for the local wavelength of the photon, show how it is created by the spin of the photon, and how this local spin is stretched by the linear motion into the wavelength we see and measure. I prove that the transform from the local wavelength to the measured wavelength is c2, showing why this term is found in the famous equation E = mc2.
In previous papers I have shown that photons have a number of stacked spins, explaining the mysteries of superposition and so on. But here I will look at the linear motion of photons. I will study how the measured wavelength is caused by the wavelength of the spins, and how different colors are created.
Before we get into that, I would like to give credit to Descartes, who knew that color was caused by photon spins in the early 1600's. I believe he made this proposal in Dioptrique, around 1638. This was before Newton's corpuscles, so the fact that Descartes was able to intuit an answer so close to correct at that time is extremely laudable. If I remember correctly, Descartes got the energies reversed from red to blue, but connecting color to spin was a masterstroke in itself. We will see that color is due to the size of the photon, which is more a matter of radius than spin velocity, but the two are inextricably linked. It is spin collisions that cause the spin radius, so we would obviously have no spin radius without spin. Since

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Rank: 20
Score: 56.030396
Retrieved Text: Planck’s constant is a number, it describes the size of the energy packets that are contained within light. These packets of energy are called photons. Planck’s constant is given the symbol h and the value of h is equal to 6.63 x 10-34⁻³⁴ J\se.
While Planck’s constant can now be found in many equations, the equation that defines Planck’s constant is called the Planck-Einstein relation. Max Planck theorized that energy was transferred in chunks is known as quanta, equal to hυ. The variable h is a constant equal to 6.63 x 10-34⁻³⁴ J\sec based on International system of units and the variable υ represents the frequency in Hz. This equation allows us to calculate the energy of photons, given their frequency.
H = Plank’s Constant = 6.63 x 10-34⁻³⁴ J\sec = 4.136 x 10⁻¹⁵ eV.
If the wavelength is known, we can calculate the energy by using the wave equation to calculate the frequency and then apply Planck’s equation to find the energy.
Planck’s law: It states that electromagnetic radiation from heated bodies is not emitted as a continuous flow but is made up of discrete units or quanta of energy, the size of which involve a fundamental physical constant.
Problem: A Green light has a wavelength of 500nm. Determine the energy for the Green light in Joules?
∴ Frequency (υ) = 0.6 x 10⁻³/ sec.
∴ E = 3.98 x 10⁻³⁸ J/ Photon.

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Retrieved Text: Throughout our history, many of our greatest scientific progresses have come from what are called, thought-experiments. Now, I, being extremely thoughtful like all the time, participate in a lot of thought experiments that may or may not have bearing on the world at all, but it's really fun to think about the world differently than what we perceive it to be. So, i think I should partake in a thought experiment with all of you guys, just see what happens.
Okay, a photon is a particle of light that is derived off of a reaction from an atom. This can be many things, but for this case say the Sun makes a photon. This photon moves in a predictable wave that travels at a high speed in a straight line until pushed or pulled by a force or reflected off of an opaque surface. Say this photon does not get reflected and it goes out into the universe forever and ever, unstopped.
3. the proton collapses on itself causing a giant reaction, possibly making more protons in a chain reaction, sparking the question, where did the protons come from?
if light stopped moving, would it esist?
do you keep meaning to say photon and not proton?
If I understand entrophy correctly, and I don't claim to, then the photon would not surive the excelleration process. Thus it would be completely obliterated and it's energy nullified.
As I understand it we are talking about a proton, and flat out, if no other force acts on that proton it will continue on forever and

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Retrieved Text: Which makes more sense: that photons [and other quantum objects] are neither waves nor particles or that they both waves and particles?
I found the following statement in 'The Feynmann Lectures in Physics', Volume 1, page 2-7: '...things which we used to consider as waves also behave like particles, and particles behave like waves; in fact, everything behaves the same way. There is no distinction between a particle and a wave. So, quantum mechanics unifies the idea of the field and its waves, and the particles, all into one.' Feynmann goes on to explain that the frequency of the field (e.g., light; PZ) and the ability of the equipment we use to measure the frequency of the field determine whether the field looks to us like a particle or a wave.
Answered by: Philip Zell, Ph.D. Physics, ACT, Inc.
where 'E' stands for energy, 'h' stands for planks contant which is equal to ~6.63608 * 10-34 joules/sec, 'v' stands for frequency of wave, and 'n' represents a positive integer.
Physicists interpreted the Planks statement as the 'quantum theory' which states that the energy packets are of fixed amount i.e. quantised.
Later in 1905, Einstein presented his 'photon theory' carrying the Plank's idea of packeted energy. Einstein proposed that the radiation is in fact particulate. Einstein further presented the properties of 'blackbody radiation' and 'photoelectric effect' which proved that electromagnetic radiation which is 'wavelike'(shows properties of refraction and defraction) also behaves as 'particlelike'.
here 'h' represents the plank's contant, 'm' represents the mass of the particle, and 'v' represents the velocity of the

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Retrieved Text: The wave theory of light, which Maxwell’s equations captured so well, became the dominant light theory in the 1800s (surpassing Newton’s corpuscular theory, which had failed in a number of situations). The first major challenge to the theory came in explaining thermal radiation, which is the type of electromagnetic radiation emitted by objects because of their temperature.
An apparatus can be set up to detect the radiation from an object maintained at temperature T1. (Since a warm body gives off radiation in all directions, some sort of shielding must be put in place so the radiation being examined is in a narrow beam.) Placing a dispersive medium (i.e. a prism) between the body and the detector, the wavelengths (λ) of the radiation disperse at an angle (θ). The detector, since it’s not a geometric point, measures a range delta-theta which corresponds to a range delta-λ, though in an ideal set-up this range is relatively small.
The experiment outlined above detects dI, and therefore R(λ) can be determined for any desired wavelength.
The total intensity radiated over all wavelengths (i.e. the area under the R(λ) curve) increases as the temperature increases.
The value of the wavelength λmax at which the radiancy reaches its maximum decreases as the temperature increases.
The above description involved a bit of cheating. Light is reflected off objects, so the experiment described runs into the problem of what is actually being tested. To simplify the situation, scientists looked at a blackbody, which is to say an object that does not reflect any light.
Consider a metal box with a

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Retrieved Text: The most important part of an LED is the semi-conductor chip located in the center of the light source. The chip has two regions separated by a junction. The p region is dominated by positive electric charges and the n region is dominated by negative electric charges. The junction acts as a barrier to the flow of electrons between the p and the n regions. When sufficient voltage is applied to the semi-conductor chip, the electrons are able to cross the junction into the p region.
Each time an electron recombines with a positive charge, electric potential energy is converted into electromagnetic energy. For each recombination of a negative and a positive charge, a quantum of electromagnetic energy is emitted in the form of a photon of light. This photon has a frequency determined by the characteristics of the semiconductor material (usually a combination of the chemical elements gallium, arsenic, and phosphorus). LEDs that emit different colors are made of different semiconductor materials. Said simply, LEDs are tiny “bulbs” fit into an electrical circuit. However, unlike ordinary incandescent bulbs, they don’t have a filament. LEDs are illuminated solely by the movement of electrons in a semiconductor material, making them energy efficient and extremely resilient over long periods of time.
LEDs don’t have a filament to burn out or break; therefore, they last much longer than conventional bulbs. Given that a very small semiconductor chip runs an LED, they are very durable and tend to last many thousands of hours. Moreover, LEDs are “instant on,” much like halogen lamps,

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Retrieved Text: If I asked you to picture a photon, an electromagnetic wave, I’d expect the image that popped into your head to look something like the one below, with the characteristic intertwined sine curves of the electric and magnetic field vectors.
This model of electromagnetic radiation dates back to the work of James Clerk Maxwell, whose differential equations laid the groundwork for the pre-Einsteinian understanding of electricity and magnetism, and to this day, this is still how most students first learn to think about the quantum of light—as a plane-polarized wave, composed of perpendicular 2D components.
Pictured this way, however, the photon behaves unlike any familiar 3D system, with its components shrinking out of existence before popping back in, upside-down. As for analogies, waves on the surface of a pond fall short by a full dimension, leaving the student wondering which way is “up”, and what provides the restoring force equivalent to gravity. Once a student understands the derivative relationship between electricity and magnetism—that one is induced by a change in the other—the nature of light starts to make more sense mathematically, but this doesn’t make it any more intuitively palatable, and accepting the peculiar undulations of the sine wave as a real, physical thing can be a difficult stumbling block for people to surmount. But there’s an easier, more fundamental way to think of photons—it’s surprising at first, but ultimately a great relief to learn that the plane-polarized electromagnetic wave pictured above is not one photon, but two! In truth, neither part of the photon ever vanishes, or

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Retrieved Text: Photon emission processes have corresponding absorption processes. We will mainly consider X-ray absorption.
Take an astronomical source at distance L from the observer.
The fraction of volume, dV, which h is blocked by the presence of element Z can also be thought of as the probability that a photon from the sourceis absorbed in volume dV.
Integrating over length from source.
Including all elements in the line of sight:.
Where nH is the interstellar hydrogen number density, and NH is the number of H – atoms per m2. Column density is measured from the 21 cm atomic hydrogen line but there is a factor of 2 uncertainty due to e.g. wide beams. Also the contribution to the column from molecular hydrogen is unknown since it is much harder to measure; it is believed to follow the same distribution of atomic hydrogen.
These derivations assume that the ratio of nZ to nH is constant along the path, while nH varies with distance from the observer.
Photoionization leads to recombination of the removed electron, thus photoionization removes X-ray photons – also extreme UV photons – and dominates in these bands.
The two forms of electron scattering, Thomson scattering and Compton scattering, remove photons from the line of sight. In Thomson scattering, the photon energy is much lower than the rest mass of the electron and is just deflected, while in Compton scattering, the photon effectively transfers some of its energy to the electron, thus light is absorbed.
At very high energies, photons can collide with ambient photons and form an electron-positron pair, i.e. photon energy is lost

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Retrieved Text: measuring it, and using it.
we creatures made of matter need methods of interacting with light.
but until now, we really haven't considered how.
Light production falls into two major categories: incandescence and luminescence.
Incandescence is how filament light bulbs produce light.
emitting more and more light as the temperature increases.
created by the intense vibrations of atoms and electrons at high temperatures.
the oscillation of atoms in objects creates light waves.
be wrapped up in a neat little bundle we call a photon.
which are sometimes called cold body radiation.
electron orbits move in orbits around the nucleus.
it emits or absorbs a photon of specific energy to do this.
There are many subcategories of luminescent processes.
which we can't see into visible light.
and triboluminescence produces light when we chew on hard candies like lifesavers.
let's make sure we can measure its properties.
When we want to take a measurement of light, what are we measuring?
at just under three times 10 to the eight meters per second.
the frequency, or the energy that the photon packets carry.
A typical red laser emits a beam of photons with a wavelength of 650 nanometers.
or even in terms of the photon energy, 1.9 electron volts.
one of many will come across in this course.
single electron moving across an electric potential difference of 1 volt.
1.6 times 10 to the minus 19 Joules.
The naming and labeling of light can be confusing.
and frequency can all be considered as equivalent ways to describe light.
characterized by its frequency, say 102.9 megahertz.
between 400 and 700 nanometers.
that allow you to determine the other quantities.
the speed of light c. Let's double check the values

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Rank: 28
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Retrieved Text: A stationary atom sees the laser neither red- nor blue-​shifted and does not absorb the photon.
An atom moving away from the laser sees it red-​shifted and does not absorb the photon.
An atom moving towards the laser sees it blue-​shifted and absorbs the photon, slowing the atom.
The photon excites the atom, moving an electron to a higher quantum state.
The atom re-emits a photon. As its direction is random, there is no net change in momentum over many atoms.
Doppler cooling is a mechanism that can be used to trap and slow the motion of atoms to cool a substance. The term is sometimes used synonymously with laser cooling, though laser cooling includes other techniques.
Doppler cooling was simultaneously proposed by two groups in 1975, the first being David J. Wineland and Hans Georg Dehmelt and the second being Theodor W. Hänsch and Arthur Leonard Schawlow. It was first demonstrated by Wineland, Drullinger, and Walls in 1978 and shortly afterwards by Neuhauser, Hohenstatt, Toschek and Dehmelt. One conceptually simple form of Doppler cooling is referred to as optical molasses, since the dissipative optical force resembles the viscous drag on a body moving through molasses. Steven Chu, Claude Cohen-Tannoudji and William D. Phillips were awarded the 1997 Nobel Prize in Physics for their work in laser cooling and atom trapping.
Doppler cooling involves light whose frequency is tuned slightly below an electronic transition in an atom. Because the light is detuned to the "red" (i.e. at lower frequency) of the transition, the atoms will absorb more photons if they move towards the

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Rank: 29
Score: 53.63282
Retrieved Text: Intended principally for students in engineering and the physical sciences as a continuation of PHYSICS 152L. Topics include: mechanics from a microscopic perspective, the atomic nature of matter, energy, energy quantization, entropy, the kinetic theory of gases, the efficiency of engines, electromagnetic radiation, the photon nature of light, physical optics and interference, waves and particles, applications of wave mechanics. Not open to students having credit for PHYSICS 142L or 162L. Prerequisites: PHYSICS 152L and MATH 212 or the equivalents. One course.

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Input Text: Read the passage below and choose the right answer to the following question (choices are increases or decreases. ):

As the distance between the objects increases the magnetic force of attraction decreases.


Lisa is hitting a tennis ball against the wall. As the tennis ball bounces towards the wall and away from her, the magnetic force of attraction between the wall and the ball increases or decreases.?

Target Text: increases

#### Retrieved Documents ####

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Score: 72.08593
Retrieved Text: So, rather than dreading the thought of hitting against the wall – human or otherwise – you can actually use the wall to not only improve your game and hone your strokes, but also to improve your conditioning and your ability to outlast those ‘human walls.’ With the proper motivation, attitude and training, you can make this unbeatable foe a wonderful tennis conditioning buddy. Here’s how I train my tennis fitness training clients using the wall.
Of course, first things first! Always start with a proper warm-up (e.g. dynamic warm-up and a few easy strokes against the wall to warm-up). Now you’re ready to PLAY!
Start by playing out a tennis point against the wall. Simulate a 20 – 30 second point by trying to keep a single ball in play for that entire time (hitting forehands and backhands). Keep a few extra tennis balls in your pocket so that if you cannot keep the single ball in play for the designated time, you can take one out of your pocket and continue with minimal delay. After hitting for the designated time, take a short break – simulating the time between points (e.g. 20 seconds or so), then begin again. Continue this process for several points, alternating your hitting time from between 15-45 seconds, and your ‘rest’ time between points to anywhere from 5-20 seconds. By using this type of ‘interval’ tennis conditioning session, you would begin to notice improved tennis-specific cardiovascular conditioning and be better prepared to meet, and beat, those human-wall opponents that seem to give

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Retrieved Text: Inspect the activity area and eliminate potential hazards. Check that the activity surface provides safe traction. Identify a line that is a safe distance from the wall and that the ball must cross to be played. Players are not to attempt playing any ball in the area between the line and the wall. Provide a safe distance between activities.
Each pair finds a space against a wall and marks out their court using a pylon for each of the back corners and a pylon beside the wall for each of the front corners. Participants divide their court into two sides by putting one pylon in the middle of the square between the back pylons and another pylon beside the wall between the front pylons.
Participants use their hands as a paddle to hit the ball so that it hits the wall and bounces into their opponent’s area. Participants try to hit the ball so it is challenging for their opponent to return.
The opponent tries to return the ball to the other side of the court before the second bounce.
A point is scored by a participant if their opponent is unable to return the ball before the second bounce, or if the ball does not land within the boundaries.
The leader asks open-ended questions to help participants refine their movement strategies and tactical solutions during the activity. Examples: Describe how you decide where to send the ball against the wall in order to make it a challenge for your opponent to return the ball to you. What does your body

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Score: 60.025932
Retrieved Text: We have put together a list of words that are similar to BACKBOARD.
1 A board for the back; a board placed at the back or serving as the back of something.
2 A board used in a lathe to sustain the pillars supporting the puppet-bar.
3 In English [Yorkshire] coal-mining, a thirl or cross-hole communicating with the return air-course.
4 In leather manufacturing, to board on the flesh side instead of on the grain side as in regular boarding.
5 The flat vertical surface to which the basket is attached.
6 A flat vertical wall with the image of a tennis net drawn or painted on it. Designed to practice hitting against such that the ball bounces back.

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Retrieved Text: If you are looking for an interesting activity to help your child improve his or her motor skills, get physically fit and have fun all at the same time, why not try out some components of the Fun Tennis Challenge?
Taking on a game-based approach, the Fun Tennis Challenge emphasizes on modified tennis drills to improve an individual’s Fundamental Motor Skills (FMS), and is suitable for young children aged between six to 11 years old.
The Fun Tennis Challenge helps in the development of the key elements required in tennis - hand-eye coordination, agility, balance, flexibility, speed, and strength. Therefore, it serves as a base for a beginner to pick up the sport with ease and is also used by recreational tennis players to refine their tennis strokes.
The aim of the Swamp Crossing drill is to get to the finish line by stepping only on the markers, which are spaced out in zones of 2m or 1.5m widths. Developing balance and flexibility is essential for tennis, as opponents will attempt to place the ball beyond a player’s reach.
Facing a wall, players simply have to throw and catch the ball as many times as possible within a minute, without letting the ball fall to the ground. The ball catching drill improves hand-eye coordination and focus, both important traits in tennis, as players must return the ball over the net before it bounces out of their court.
Players have to balance a ball on their racquet face, while winding around the cone set-up in a zig-zag fashion. The swift and sharp

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Score: 54.611534
Retrieved Text: Tennis Player Metal Wall Art is made of flat iron, bent and welded together by hand to create this unique female tennis player hitting the ball on her two hand backhand stroke. This wall decor has powder coating finish for indoor or outdoor use. So, it’s handcrafted for durability and long lasting decorative. It’s an excellent gift item for tennis players and fans. A perfect wall hanging to decorate their bedroom, sports room and man cave. When hung properly, it will produced a 3D effect cause by the shadow behind it.

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Retrieved Text: Your best practice partner ever - It never misses and hits it just where you like it!!!
To operate the ball machine a key and a bag of tennis balls are to be picked up at the front desk. You will need to leave an ID as collateral.
Reservations may be made in half hour increments from 8am - 8pm any day of the week. You may call the front desk up until 24 hours in advance 415-383-3483 to reserve a half hour on the ball machine.
A maximum of 4 players may use the ball machine or be on the ball machine court at one time. Non playing people must be seated on the bench for safety reasons.
Please read all instructions located on the control panel prior to using the ball machine. They are very specific and will enhance your ball machine experience.
Non-members may not use the ball machine unless accompanied and signed in by a member.
All members and players are urged to display a reasonable and cooperative behavior relative to the use of the ball machine. Members must use caution in using the machine. Members should report any malfunctions to the office immediately. If it begins to rain, stop immediately, pick up the balls and return them to the front desk. Wet balls ruin the machine and are useless once they are wet.
On the ball machine court we also have a back board to hit against. It is placed against the fence slightly in an angle so you need to place yourself in such a way that

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Retrieved Text: A tennis rally occurs when players hit the ball multiple times, usually after it bounces, while a volley is a ball hit out of the air before it lands. Players rally as part of a warmup, practice or drill session or during points when playing a match. Players generally rally from the baseline, and hit volleys when they are near the net. Rallying using different drills can improve your footwork, speed, cardio stamina and muscular endurance, and burn calories.
Rallies are stroke exchanges during which tennis players begin to return their partner’s or opponent’s shots after the serve has landed. Your ball must cross the net on a fly after you hit it, meaning the ball can’t touch the ground on your side of the net after you hit it. The rules of tennis require able-bodied players to hit the ball on a fly or after only one bounce, while wheelchair players may hit the ball after two bounces. Players usually rally from the baseline, using forehands and backhands.
Volleys are shots players hit out of the air that are not overheads or serves. Volleys are hit from head height or below, while overheads and serves are balls hit out of the air well above the head. Players normally hit volleys from the midcourt as they are approaching the net, or while they are standing near the net. The ball must cross the net without touching the ground to be good. Your racket can cross the net after you hit the ball, but not touch the net, and

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Rank: 7
Score: 52.440567
Retrieved Text: Tennis (occasionally called "lawn tennis" to distinguish it from royal tennis, an obscure indoor game) is a racquet sport played between either two players (singles) or two teams of two players (doubles). Tennis is played on a 78' x 27' (78' x 36' for doubles) court, which is divided in the middle by a net, such as that each side measures 39' in length.
Players attempt to hit a tennis ball with a tennis racquet such that it bounces in the opposition's side of the court and the opposition is unable to return it. A legal return is made by hitting the ball over the net, after not more than one bounce on one's side of the court. Each point is started by a player who initiates play by "serving" the ball into a designated area on the other side of the court. Tennis is an Olympic sport which is played in many countries around the world.
In most tournaments, if the game score in a set reaches 6-6, a series of points called a tie-breaker takes place. The first side to win 7 points, with at least 2 more points than the other side, wins the tie-breaker. The score of the set is recorded as 7-6.
A tennis player usually has several types of swinging shots at his or her disposal: the forehand, backhand, volley, overhand smash and slice shot. When a player serves the ball to the other player, at the beginning of each point, he or she most commonly employs the overhand smash method, or the

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Score: 52.366173
Retrieved Text: Our trip to Epps Sporting Goods would affect my life even today. Dad took me to buy my first tennis racket. I was about twelve years old and I had decided to learn to play tennis because my older brother played tennis and I wanted to be like him.
Dad checked out the cheap tennis rackets and found one that would fit into his budget. He didn’t want to buy an expensive racket because he didn’t know if my desire to play tennis was just a passing fancy. When we arrived home, Dad gave me my first and only tennis lesson. He took me out in the backyard. Then, he handed me a tennis ball and told me to keep hitting the tennis ball up in the air. This would get me use to hitting the ball as well as keeping my eye on the ball. I continued to do this every day. I began to imagine myself becoming the next Rod Laver.
By the time, I was in eighth grade, I would take my tennis racket to Ford Park and hit the tennis ball off the tennis court wall. The problem was that I would often hit the ball over the wall, which meant I spent more time retrieving my ball than hitting it. Eventually, I could hit the ball with some regularity. Now I was ready to hit with anybody who was willing to hit with a young person who had a great desire to play tennis, but not much ability.
One man, who took a special

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Score: 51.78859
Retrieved Text: Squash is a racquet sport played on an enclosed four-walled court. The ball can be bounced off any wall within the marked lines; every shot must come off the front wall before hitting the ground. The object of the game is to win points by ensuring that your opponent is unable to return your shot before the ball bounces twice.
It is normally played by two players, although doubles squash is becoming increasingly popular.
Squash, or squash racquets as it was known in its early days, was invented at Harrow School, England, around 1830. The first purpose-built squash courts were built at Harrow in the 1860s.
The game remained the preserve of schools and universities until the early part of the 20th century. The United States became the first nation to form a dedicated association and codify its game in 1907.
In the same year, the (British) Tennis & Rackets Association formed a squash rackets sub-committee and, in 1928, the (British) Squash Rackets Association took over.
Only when commercial operators began building public courts from the 1950s did the game start to boom in popularity, with participation peaking around the early 1980s.
Until then, the game was divided between amateur players and professional players, who were often coaches employed by exclusive clubs.
Today, squash is played in 153 countries, of which 124 are members of the World Squash Federation, with 50,000 courts now worldwide. Squash made its debut at the 13th Asian Games in Bangkok 1998.
It is also played in the World Games, All Africa Games, Pan-American Games and Commonwealth Games.
Squash is played

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Retrieved Text: Many people either know Squash as a food item or something that people play at country clubs. Believe it or not, squash (the game), has found its way into Briarcliff High School.
Squash is a racquet sport played by two or four players (singles or doubles) in a four-walled court with a small hollow rubber ball. The game is not played like tennis where opponents stand on opposite sides of the court but more like racquetball as you would see at some gyms such as Club Fit. The players alternate shots, hitting the ball off of the playable surfaces of the four walls of the court. In order to see who serves rst, the players spin a racquet to decide who will serve first. The serve can either be from the left or right service box and must go above the service line and below the outline. Then, after the serve the opponents hit the ball off the front wall alternating after every shot. They must hit it below the outline and it must not hit the ground right after hitting the racket. All the walls are playable however, the ball must hit the front wall.
The team, organized by Sophomore Caleb Schumacher, consists of BHS students including fellow sophomore Nick Sama who provided some background information about the team.
“Squash is a great way to get exercise and have fun playing with your friends,” he added.
The games are Mondays and the team plays in different facilities such as Chelsea Piers against teams from other towns. Also, the team

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Score: 50.577705
Retrieved Text: The Japanese really do seem to invent a lot of sports, especially for the disabled. Not long ago, we told you about Doglegs, a wrestling sport for the handicapped. Now, we’re going to introduce you to Blind Tennis, which is of course, tennis played by the blind.
The creation of the sport is largely credited to Miyoshi Takei, who in spite of his blindness, started to play tennis as a kid with the encouragement of his high school teacher. His only aim at the time was to hit a ball that was flying through the air as hard as he could, even though he couldn’t see it. After several trials, he finally invented a special kind of tennis ball that is spongy and light in weight. The ball rattles, so that blind players can track its movement with their ears. Miyoshi’s endeavors met with success and the first national blind tennis championships were held in Japan in the year 1990. Today, hundreds of Japanese players take part every year and a few from other countries too, such as China, Korea, Taiwan, Britain and the United States.
Interestingly, blind tennis is played on a badminton court with string taped to the lines so players can feel the boundaries. Junior-sized rackets are used to hit the ball. Players who are deemed legally blind wear eye masks to level the field. They are expected to hit the ball after it bounces two to three times, depending on the level of their visual impairment. Sadly, Miyoshi is no longer alive to see

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Score: 50.461163
Retrieved Text: Tennis is one of the most popular sports in the world. It is played either as a single person or double with a partner against two others. The sport consists of a strung oval racket, a hollow rubber ball covered in felt and a net. The goal is to hit the ball over the net to the other team in a way that they are unable to play it back. Tennis is played recreationally by millions all over the world. At VinylDisorder.com, we specialize in providing our customers with a huge selection of options with just about any design. Our tennis d�cor is a popular choice in both weather resistant car vinyl and removable wall vinyl.

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Score: 50.333084
Retrieved Text: A high-paced, very high-density tournament quality ball developed specifically for high-octane Mini Tennis play, such as touchtennis, the Attack! is designed for longer rallies and more exciting tennis on a smaller court.
Not to be confused with a children's development ball; the Attack! bounces fast and high.
Popular choice for university tennis clubs, adult Mini Tennis groups, and touchtennis.

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Rank: 14
Score: 50.010883
Retrieved Text: Scoring is as in lawn tennis. To win a game a player needs to win four points and, usually (but not if playing off a handicap adjustment), to be at least two points ahead of his opponent. The first player to win six games wins the set (usually – but sometimes sets are played as first to 8 or 9 games) but it is not necessary to be ahead by two games; the eleventh game is decisive (or the 15th or 17th).
It is the score of the player who won the last point that is called first. (This is different to lawn tennis).
Service is only from one end of the court.
For the service to be correct: The ball must touch the half of the side penthouse at the receiver’s end; the ball may also touch the side penthouse at the server’s end and/or the side wall. The first bounce of the ball must be on or beyond the service line at the hazard end (the receiver’s end). The server must stand further from the net than the second gallery line. The ball must go over the net but it can first strike the wall or the side penthouse at the striker’s end.
The ball is out if it strikes the side walls above the marked limits or hits one of the rafters or lights.
A ball entering the dedans, the grille, or the winning gallery wins a stroke for the striker.
A ball entering any other opening at the end opposite the striker, or bouncing twice on the floor

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Rank: 15
Score: 49.85327
Retrieved Text: The thimbles should be spaced out that ยางปิงปอง donic requires players to build paper skyscrapers. I want to put the rubber from the broken paddle little of quarters, but much more kid-friendly and on a larger scale. Kneeling lower as the slinky is tossed up can give pence pasta, be sure to purchase larger pasta. You may also select ready-made rackets and to grip the cups and keep them from falling out of your hands. However, you can’t hit very hard with tensor rubber, as if you and employees through luxury table tennis equipment. In addition to the rubber layer, some paddles also have textures known as pimples, dimples so keep those feet moving quickly. Exposure to excess moisture and high or low temperatures (3 on the bottom, 2 in the middle and 1 at the top). Look for places where the texturing is thinned review and see the game being played. Please try a new search or the Picardy region, where the Cornilleau family originates.
It will help you to keep the paddle in excellent cleaner are out there? Dexterity, speed, and skill are all required in this fun, family-friendly challenge that things to consider is the colon of the paddles. In the ยางปิงปอง highly technical world of table tennis equipment, Butterfly strives to give our customers as the surface of the rubber of your paddle. The all-round player or players with shorter strokes must go fishing, but not in the traditional way! This Blows is exciting and fun thick, sturdy handle to give your stroke

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Rank: 16
Score: 49.789845
Retrieved Text: Create a bouncing ball that bounces in a believable, realistic way. The action should be smooth and flowing. This is a 4-stage exercise - do as much as you have time for.
Animate a ball bouncing on a looping cycle.
Adjust the timing in the graph editor to give the ball different qualities. Say, a rubber ball, a tennis ball and a lead cannon ball.
Add a translation so the ball bounces forwards and gradually comes to rest.
(If you have time) put the ball in a simple environment, say on a ping pong table, or have it bounce down some steps.
You can also import free sets and props from turbosquid.
Check YouTube for video reference of balls bouncing.
Watch a ball bouncing yourself - study the motion. Note how different balls with different properties bounce, such as a lead ball or a rubber ball.
You can either create a ball yourself using create/polygon primitives/sphere.
Also see our blog post about the ball rigs here.
It will take roughly 2-3 hours to watch all the videos this week. You should watch them in the order shown.
This week's handout is a thumbnail sketch of a ball bouncing.
Import one of the bouncing ball rigs (see above) from highEnd3D.com or create a polygon primitive.
Start off by getting the ball to bounce up and down.
Then, once you have done this, copy and paste the curves so that it bounces several times.
Now add a forward translation in the z axis so that the ball bounces along in a direction.
Adjust the bounce so that the ball bounces slightly less, and lower,

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Rank: 17
Score: 49.688473
Retrieved Text: Is Plantar Fasciitis Causing You Pain?
Massage therapy can help with the pain associated with plantar fasciitis! Massage therapist can help release the tension in the plantar fascia as well as the leg muscles from the calves to the glutes, along with stretching the calf, heel and foot.
Stretching the calves regularly can help in the healing process to keep the gastrocnemius and soleus muscles flexible. You can do this by doing a slight lunge and leaning towards a wall, or by dropping your heels while standing on a stair or curb. You can also use a towel or belt to stretch when you get up and before you go to bed.
Self massage to the plantar fascia can help alleviate pain as well, however you do not want to do this during the acute phase (when the pain is very high) as it will be very uncomfortable. You can use a can of soup, a tennis ball, or a golf ball to roll the bottom of the foot. if you have a desk job put a golf ball under your desk and take your shoes off, keep the plantar fascia loose while you work away! Another great relief is an iced water bottle, ice helps reduce pain and can provide relief during acute phases. Doing these stretches and tips to help with pain twice a day can help improve the pain you feel from plantar fasciitis.
Foam rolling is another fantastic self care tool you can do at home! It will help release tension in the leg muscles! Using

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Rank: 18
Score: 49.51607
Retrieved Text: Wheelchair tennis is regulated by the same rules as able-bodied tennis through the International Tennis Federation except wheelchair tennis players are allowed two bounces of the ball. The player must return the ball before it hits the ground a third time. The wheelchair is part of the body and all rules that apply to a player's body also apply to a player's wheelchair.
Originating in the USA in 1976, tennis is the most rapidly growing wheelchair sport in the world. Today the International Wheelchair Tennis Federation has 48 member nations and has been a Paralympic sport since 1992.
To be eligible to play wheelchair tennis a player must be medically diagnosed as having a mobility related disability that requires the use of a wheelchair.
It's easy! Just call a friend, pick up a racquet and some balls and head down to your local park. Or just contact Wheelchair Sports NB Tennis representative for information on beginner programs.
Anybody with a permanent mobility related physical disability can enter a sanctioned tournament.
What is unique about wheelchair tennis?
The beauty of wheelchair tennis is that you can play with your able bodied friends and family as well as other wheelchair players.
The wheelchair player is allowed two bounces and the able bodied player is allowed one bounce.

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Rank: 19
Score: 49.491432
Retrieved Text: Why does it hurt more when you fall down on pavement then when you fall on the grass? The materials that make up grass and pavement are different which makes objects hitting the two surfaces behave differently.
When an object is moving (like you!) it has energy. When it hits the ground some or all of this energy is absorbed by the ground. The grass and the soil underneath it feel softer because they absorb more energy than pavement.
In this experiment, you will test the amount of energy absorbed by different types of materials by dropping balls and water balloons.
Make sure no one is going to get hit before you throw a ball or water balloon.
First you are going to use a tennis ball to test how much energy is absorbed by pavement and grass. Find some pavement, maybe in your driveway or on a sidewalk. Hold the tennis ball one foot above the pavement, and hold the ruler up as shown in the picture. Release the ball and watch to see how high it bounces after it hits the ground. Make sure the zero end of the ruler is on the ground, and measure in inches how high the ball bounces. Try it again and count how many times the ball bounces before it comes to rest. Make sure you are not throwing the ball down; just release it and let it fall. Record your data.
Next, move to an area with grass, dirt, or bark. Repeat the above experiment, recording how high the first bounce is

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Rank: 20
Score: 49.215157
Retrieved Text: Yonex Poly Tour Strike is the latest poly string coming out of the Japanese company. Yonex describes the string as, “For competitive players who rapidly fire attacking shots at fast swing speeds; minimal performance decline even after competitive play.” So let’s see how Yonex Poly Tour Strike played for me!
I absolutely love to string tennis racquets, I personally find it very calming and I think there’s a certain art to restringing a tennis racquet. However, there are times that I come across a challenging tennis string to install; Yonex Poly Tour Strike was not one of those. In fact, this tennis string was very easy to install. Weaving crosses was a breeze, the coating made it very easy to run the strings against each other (potential snap-back greatness?).
I strung Yonex Poly Tour Strike at 46lbs (20.8kg) in my Yonex VCORE Duel G 97 310 thinking that would be a good middle ground for my normal tension. When I pulled it off my machine and gave it a few “bounces off the pad of my hand” it sounded nice and felt good. I was very excited to get this string out on court for a playtest.
*Side note: The coloring of the string, while not black or silver but more of a dark slate grey, is unique. It’s shiny, almost looks black at certain angles but not when up close. Looks pretty fresh.
Like I do with all my reviews and all my hitting sessions, I do a little mini-tennis to warm up. I do this to find my

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Rank: 21
Score: 49.213932
Retrieved Text: Squash Tips: THE BASICS YOU NEED TO KNOW TO PLAY SQUASH!
Picture a tennis court , you have your side of the court, the net, and your opponent's side of the court.
The same is for the squash court: the lowest line is called the ''TIN'' which is the same as the tennis's net. If the ball Hits it or goes lower, the ball is down.
The highest line it's the upper limit for the ball, this means that if the ball touch the line or goes above it it's out.
The line in the middle is the service line, you need to throw the ball over this one when you serve.
Since the serve must be a fair shot,when you're serving you have to follow this 3 rules.
You can use the side walls to get the ball to hit the Front wall. This means that after you have hit the ball, it has to bounce onto the front wall, before bouncing on the ground.
The Match is divided in games, every game is won by the first player that scores 11 points, generally you can play a match where the first player to win 2 games (it's called 2/3) or the first to win 3 games (3 out of 5 games) wins the match.
For you to score a point your opponent must throw the ball down or out or the ball must be not-up when your opponent has to it it.
Not-up means that the ball bounces twice on the floor before the opponent hits it.
Follow this 2 simple tips in order

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Rank: 22
Score: 49.145996
Retrieved Text: Speaking on Sky Sport the former world No. 25 Filippo Volandri commented on the upcoming Indian Wells final between Roger Federer and Dominic Thiem. The Italian said the Austrian can be very competitive against the Swiss. "It's dry, there is no humidity, the the ball bounces a lot, and Thiem makes it bounce so much on the backhand side but mostly on serve.
Against Milos Raonic, he served like Milos usually does, he almost hit 90 percent first serve in and his kick serve bounced a lot." On Thiem's progresses, Volandri added: "Last year Thiem struggled, he did also this year but week by week he improved and he played a great tennis.
He was also lucky because Gael Monfils withdrew from their quarter-final match. I thought the Frenchman would reach the final. But against Raonic, Thiem played a really good match, he knows how you can do it because he beat Federer on clay and also on grass, which makes you think a little bit.
So for me the match will be balanced." On Thiem's tactics against Federer, Volandri concluded: "Thiem will have to hit a lot of first serves in, and hit great passings. He was perfectly balanced against Raonic, hitting being far away from the baseline as well.
Federer will not make Thiem hit too much from the baseline. We will see a lot of chip and charge, with Roger hitting inside the baseline and he will be very fast." Federer is coming into the final being fresh as Rafael Nadal withdrew from their semifinal clash due

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Rank: 23
Score: 49.08591
Retrieved Text: One of the best tennis coaches I have ever known and learned from was Coach Jim Leighton of Wake Forest University and the Old Town Club in Winston Salem, N.C. In the early days, as legend has it, on any given Sunday you could find Dennis Van Der Meer or Vic Braden sitting in the shop discussing tennis technique and strategies with Coach Leighton. I do not know if this is true or not but he was one heck of a coach.
When Coach Leighton referred to strategy he believed that hitting the ball crosscourt was the only direction for a player to go most of the time. He felt there were very few instances that a player should hit the ball down the line. Learn those few instances where you need to go down the line with your shot and the rest of the time you can hit the ball crosscourt–do this and you will win a lot!
There are four major reasons for a player to think in terms of hitting the ball crosscourt. First, the geometry of the tennis court dictates that we hit the ball crosscourt. Since we play on a rectangle, the court is longer from one diagonal to the other by several feet. Second, the net is higher when attempting to hit the ball down the line. The net is lower in the middle when going crosscourt. Third, when hitting the ball crosscourt the ball is moving in a direction away from your opponent and the court becomes wider for them. Have

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Rank: 24
Score: 49.016487
Retrieved Text: What makes Maillith tennis practise walls special?
This has been unique for 40 years: with SMASH-BACK tennis walls made of polymer concrete, the unique curve geometry means you can train almost as if you were training with a real opponent.
We have developed the unique shape of our tennis practise walls in collaboration with tennis professionals. The result is the ball bouncing realistically - similar to the return from an opponent.
Our SMASH-BACK tennis practise walls train an excellent rhythm feeling as well as stroke timing. Many good tennis players have played on our tennis walls. Control, swing, reaction, footwork, stroke - everything is trained. For tennis clubs, who really want to promote their players, tennis walls are essential.
Maillith tennis walls are modular in structure. A tennis wall consists of individual elements and the elements are set up side by side.
For the construction of a SMASH-BACK tennis wall, a concrete foundation must be poured first. The galvanised steel supports are then mounted on this. Finally, the tennis wall elements made of polymer concrete panels are screwed to the steel supports and to each other.
The length of the tennis wall can be set individually. A common length is 6 m. Some customers also order so many elements that the tennis wall covers the entire playing field.
A tennis court (including double field) is about 11 metres wide. For a tennis wall with court width, either 11 elements of type I would be required or 7 elements of type II.
As an option, the tennis walls are available with a (galvanised) ball grill

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Rank: 25
Score: 48.963623
Retrieved Text: First, you have to get all the materials. Then, you have to put black marks evenly on a ping pong ball in order to see the rotation of the ball. Secondly, you must set up a high speed camera and capture the ball after it is struck. Once you have done this continue to capture the hits until you get the one you want. While doing this, duct tape the wii remote to your arm, so you can use it as an acceleramtor.
We will be testing a flat serve, a topspin serve, and a topspin forehand with the ping pong paddle and ball, testing the acceleration and speed of the wrist, hand motion. We will also calculate the speed of the ping-pong ball and it's spin, pending the camera can measure spin.
Why is Spin Important in Table Tennis?
It is probably easiest to understand how important spin is by first imagining what table tennis would be like if there was no such thing as spin. If you could not spin the ball in table tennis, what would be different?
First of all, you would be limited in how hard you could hit the ball. A table tennis table is 9 feet or 2.74 meters long. A top player can hit a ball off the bat at around 175km/hour (although it will slow down a little due to air resistance).
The ball could only be hit at full speed and power if the ball was high enough to draw a virtually straight line between the ball and a point on

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Rank: 26
Score: 48.895782
Retrieved Text: Our guests from Cyprus and Israel after an adrenalin rush playing on Padel Club courts.
Xtend Carbon fiber is characterized by using tapes instead of carbon threads. These tapes are biaxially interwoven. Thanks to this you get more resistance, more rigidity and more important, less weight. This new compound is 20-30% lighter than the common carbon fiber.
Vibradrive is a mounting system in which a highly elastic rubber piece is sandwiched dividing the handle in half. This piece absorbs most of the vibrations in the game, especially on off-center hits.
Nerve system is based on the creation of channels on the frame side, with the aim of increasing the rigidity while reducing the weight. We get more control in volleys and in general in powerful strokes.
Padel Club Riga is officially open for anyone who wants to play! Now in summer season we call it as soft opening as there are still a lot of jobs to. But we are ready to supply you with a best service also now when it’s too hot or in rainy days or when you are in sporty mood. Welcome! Make it more attractive to get to know padel sport- we offer 1st try for free. Here we warmly recommend to use professional trainer to understand technique and rules of the game. Equipment such as rackets and balls we give for free as well. Book your time here!
The best padel in the world stopped off in Barcelona to stage a great show. The centre court was set up on an impressive stage: the Real

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Rank: 27
Score: 48.714035
Retrieved Text: Stand facing a wall (or partner) from 5 feet away, holding a medicine ball at chest height. Throw the ball at the wall (or partner) 3 to 5 feet to your left and at eye level. As the ball bounces off the wall, shuffle sideways and catch it in the air or on a hop. Repeat in opposite direction.

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Rank: 28
Score: 48.659977
Retrieved Text: Table tennis is fun game. The game is fast paced especially for intermediate and expert levels. The sport originated in England and was a form of entertainment for the upper class during the late 1800s.
It was derived from the lawn tennis sport and was really supposed to imitate outdoor tennis in an indoor setting. Nowadays, people who want to take part in the sport have a range of equipment at their disposal.
To play table tennis, you first need a table of regulation size.
After the table, you will require a table tennis net. You can find this in any sports shop. And just like lawn tennis, you are not supposed to allow the ball get caught by the web. Other equipment that you will need includes good excellent table tennis ball and a pair of paddles. The paddles are the ones that you use to strike the balls back and forth between the players.
When you and your spouse are all geared up, you’re ready to play table tennis. The beginning of the game commences after the first ball is served. A coin toss can be used to ascertain which one should function first. The player who serves the ball have to let it bounce once on their side of the table then should bounce at least once on the opponent’s side.
When the opponent is able to get the function, he or she wants to return the ball to the other side before the ball bounces on her or his side another time. However, once the ball got

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Rank: 29
Score: 48.52878
Retrieved Text: Leopard Paws are a variation on our original Hitting Hands, which secure the hand with a velcro strap. Leopard Paws secure the hand by holding it inside its elasticated cover. So it couldn't be easier.
As a teaching product, Paws are excellent for large classes - so easy to put on, and there are plenty of pair games and exercises they can be used for.
Slip a hand inside the elasticated cover, and it's held against the Paw hitting board with no need to grip. And because there isn't a handle distancing the hitting surface from the hand, it's far easier for children to coordinate eye and hand, and connect hand and ball.
So how do you teach with them?
Try using them first of all with balloons, or Balloon Balls. See how many times children can tap the balloon up into the air, or volley to each other. Balloon Balls are more robust and great for hitting against a wall, or down against the floor.
Paws are 'unhanded', in that they'll fit both left and right hand. Training both sides of the body is a good thing for all sports, so swap them over and have a go with the 'wrong' hand. Then put a Paw on each hand, and volley with both.
Maybe bring in a net system and teach hitting over a net. Zsig's Early Years Mini Net System for young children works very well, with variable height Multisport Nets giving you tennis height and volleyball height for older kids. But you can always stretch some of our Race

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======= Instance Index 2552 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are increases or decreases. ):

As the distance between the objects increases the magnetic force of attraction decreases.


Lisa is hitting a tennis ball against the wall. As the tennis ball bounces away from the wall and towards her, the magnetic force of attraction between the wall and the ball increases or decreases.?

Target Text: decreases.

#### Retrieved Documents ####

Rank: 0
Score: 72.08593
Retrieved Text: So, rather than dreading the thought of hitting against the wall – human or otherwise – you can actually use the wall to not only improve your game and hone your strokes, but also to improve your conditioning and your ability to outlast those ‘human walls.’ With the proper motivation, attitude and training, you can make this unbeatable foe a wonderful tennis conditioning buddy. Here’s how I train my tennis fitness training clients using the wall.
Of course, first things first! Always start with a proper warm-up (e.g. dynamic warm-up and a few easy strokes against the wall to warm-up). Now you’re ready to PLAY!
Start by playing out a tennis point against the wall. Simulate a 20 – 30 second point by trying to keep a single ball in play for that entire time (hitting forehands and backhands). Keep a few extra tennis balls in your pocket so that if you cannot keep the single ball in play for the designated time, you can take one out of your pocket and continue with minimal delay. After hitting for the designated time, take a short break – simulating the time between points (e.g. 20 seconds or so), then begin again. Continue this process for several points, alternating your hitting time from between 15-45 seconds, and your ‘rest’ time between points to anywhere from 5-20 seconds. By using this type of ‘interval’ tennis conditioning session, you would begin to notice improved tennis-specific cardiovascular conditioning and be better prepared to meet, and beat, those human-wall opponents that seem to give

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Rank: 1
Score: 63.218555
Retrieved Text: Inspect the activity area and eliminate potential hazards. Check that the activity surface provides safe traction. Identify a line that is a safe distance from the wall and that the ball must cross to be played. Players are not to attempt playing any ball in the area between the line and the wall. Provide a safe distance between activities.
Each pair finds a space against a wall and marks out their court using a pylon for each of the back corners and a pylon beside the wall for each of the front corners. Participants divide their court into two sides by putting one pylon in the middle of the square between the back pylons and another pylon beside the wall between the front pylons.
Participants use their hands as a paddle to hit the ball so that it hits the wall and bounces into their opponent’s area. Participants try to hit the ball so it is challenging for their opponent to return.
The opponent tries to return the ball to the other side of the court before the second bounce.
A point is scored by a participant if their opponent is unable to return the ball before the second bounce, or if the ball does not land within the boundaries.
The leader asks open-ended questions to help participants refine their movement strategies and tactical solutions during the activity. Examples: Describe how you decide where to send the ball against the wall in order to make it a challenge for your opponent to return the ball to you. What does your body

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Rank: 2
Score: 60.025932
Retrieved Text: We have put together a list of words that are similar to BACKBOARD.
1 A board for the back; a board placed at the back or serving as the back of something.
2 A board used in a lathe to sustain the pillars supporting the puppet-bar.
3 In English [Yorkshire] coal-mining, a thirl or cross-hole communicating with the return air-course.
4 In leather manufacturing, to board on the flesh side instead of on the grain side as in regular boarding.
5 The flat vertical surface to which the basket is attached.
6 A flat vertical wall with the image of a tennis net drawn or painted on it. Designed to practice hitting against such that the ball bounces back.

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Rank: 3
Score: 55.467934
Retrieved Text: If you are looking for an interesting activity to help your child improve his or her motor skills, get physically fit and have fun all at the same time, why not try out some components of the Fun Tennis Challenge?
Taking on a game-based approach, the Fun Tennis Challenge emphasizes on modified tennis drills to improve an individual’s Fundamental Motor Skills (FMS), and is suitable for young children aged between six to 11 years old.
The Fun Tennis Challenge helps in the development of the key elements required in tennis - hand-eye coordination, agility, balance, flexibility, speed, and strength. Therefore, it serves as a base for a beginner to pick up the sport with ease and is also used by recreational tennis players to refine their tennis strokes.
The aim of the Swamp Crossing drill is to get to the finish line by stepping only on the markers, which are spaced out in zones of 2m or 1.5m widths. Developing balance and flexibility is essential for tennis, as opponents will attempt to place the ball beyond a player’s reach.
Facing a wall, players simply have to throw and catch the ball as many times as possible within a minute, without letting the ball fall to the ground. The ball catching drill improves hand-eye coordination and focus, both important traits in tennis, as players must return the ball over the net before it bounces out of their court.
Players have to balance a ball on their racquet face, while winding around the cone set-up in a zig-zag fashion. The swift and sharp

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Rank: 4
Score: 54.611534
Retrieved Text: Tennis Player Metal Wall Art is made of flat iron, bent and welded together by hand to create this unique female tennis player hitting the ball on her two hand backhand stroke. This wall decor has powder coating finish for indoor or outdoor use. So, it’s handcrafted for durability and long lasting decorative. It’s an excellent gift item for tennis players and fans. A perfect wall hanging to decorate their bedroom, sports room and man cave. When hung properly, it will produced a 3D effect cause by the shadow behind it.

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Rank: 5
Score: 54.202316
Retrieved Text: Your best practice partner ever - It never misses and hits it just where you like it!!!
To operate the ball machine a key and a bag of tennis balls are to be picked up at the front desk. You will need to leave an ID as collateral.
Reservations may be made in half hour increments from 8am - 8pm any day of the week. You may call the front desk up until 24 hours in advance 415-383-3483 to reserve a half hour on the ball machine.
A maximum of 4 players may use the ball machine or be on the ball machine court at one time. Non playing people must be seated on the bench for safety reasons.
Please read all instructions located on the control panel prior to using the ball machine. They are very specific and will enhance your ball machine experience.
Non-members may not use the ball machine unless accompanied and signed in by a member.
All members and players are urged to display a reasonable and cooperative behavior relative to the use of the ball machine. Members must use caution in using the machine. Members should report any malfunctions to the office immediately. If it begins to rain, stop immediately, pick up the balls and return them to the front desk. Wet balls ruin the machine and are useless once they are wet.
On the ball machine court we also have a back board to hit against. It is placed against the fence slightly in an angle so you need to place yourself in such a way that

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Rank: 6
Score: 53.067547
Retrieved Text: A tennis rally occurs when players hit the ball multiple times, usually after it bounces, while a volley is a ball hit out of the air before it lands. Players rally as part of a warmup, practice or drill session or during points when playing a match. Players generally rally from the baseline, and hit volleys when they are near the net. Rallying using different drills can improve your footwork, speed, cardio stamina and muscular endurance, and burn calories.
Rallies are stroke exchanges during which tennis players begin to return their partner’s or opponent’s shots after the serve has landed. Your ball must cross the net on a fly after you hit it, meaning the ball can’t touch the ground on your side of the net after you hit it. The rules of tennis require able-bodied players to hit the ball on a fly or after only one bounce, while wheelchair players may hit the ball after two bounces. Players usually rally from the baseline, using forehands and backhands.
Volleys are shots players hit out of the air that are not overheads or serves. Volleys are hit from head height or below, while overheads and serves are balls hit out of the air well above the head. Players normally hit volleys from the midcourt as they are approaching the net, or while they are standing near the net. The ball must cross the net without touching the ground to be good. Your racket can cross the net after you hit the ball, but not touch the net, and

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Rank: 7
Score: 52.440567
Retrieved Text: Tennis (occasionally called "lawn tennis" to distinguish it from royal tennis, an obscure indoor game) is a racquet sport played between either two players (singles) or two teams of two players (doubles). Tennis is played on a 78' x 27' (78' x 36' for doubles) court, which is divided in the middle by a net, such as that each side measures 39' in length.
Players attempt to hit a tennis ball with a tennis racquet such that it bounces in the opposition's side of the court and the opposition is unable to return it. A legal return is made by hitting the ball over the net, after not more than one bounce on one's side of the court. Each point is started by a player who initiates play by "serving" the ball into a designated area on the other side of the court. Tennis is an Olympic sport which is played in many countries around the world.
In most tournaments, if the game score in a set reaches 6-6, a series of points called a tie-breaker takes place. The first side to win 7 points, with at least 2 more points than the other side, wins the tie-breaker. The score of the set is recorded as 7-6.
A tennis player usually has several types of swinging shots at his or her disposal: the forehand, backhand, volley, overhand smash and slice shot. When a player serves the ball to the other player, at the beginning of each point, he or she most commonly employs the overhand smash method, or the

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Rank: 8
Score: 52.366173
Retrieved Text: Our trip to Epps Sporting Goods would affect my life even today. Dad took me to buy my first tennis racket. I was about twelve years old and I had decided to learn to play tennis because my older brother played tennis and I wanted to be like him.
Dad checked out the cheap tennis rackets and found one that would fit into his budget. He didn’t want to buy an expensive racket because he didn’t know if my desire to play tennis was just a passing fancy. When we arrived home, Dad gave me my first and only tennis lesson. He took me out in the backyard. Then, he handed me a tennis ball and told me to keep hitting the tennis ball up in the air. This would get me use to hitting the ball as well as keeping my eye on the ball. I continued to do this every day. I began to imagine myself becoming the next Rod Laver.
By the time, I was in eighth grade, I would take my tennis racket to Ford Park and hit the tennis ball off the tennis court wall. The problem was that I would often hit the ball over the wall, which meant I spent more time retrieving my ball than hitting it. Eventually, I could hit the ball with some regularity. Now I was ready to hit with anybody who was willing to hit with a young person who had a great desire to play tennis, but not much ability.
One man, who took a special

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Score: 51.78859
Retrieved Text: Squash is a racquet sport played on an enclosed four-walled court. The ball can be bounced off any wall within the marked lines; every shot must come off the front wall before hitting the ground. The object of the game is to win points by ensuring that your opponent is unable to return your shot before the ball bounces twice.
It is normally played by two players, although doubles squash is becoming increasingly popular.
Squash, or squash racquets as it was known in its early days, was invented at Harrow School, England, around 1830. The first purpose-built squash courts were built at Harrow in the 1860s.
The game remained the preserve of schools and universities until the early part of the 20th century. The United States became the first nation to form a dedicated association and codify its game in 1907.
In the same year, the (British) Tennis & Rackets Association formed a squash rackets sub-committee and, in 1928, the (British) Squash Rackets Association took over.
Only when commercial operators began building public courts from the 1950s did the game start to boom in popularity, with participation peaking around the early 1980s.
Until then, the game was divided between amateur players and professional players, who were often coaches employed by exclusive clubs.
Today, squash is played in 153 countries, of which 124 are members of the World Squash Federation, with 50,000 courts now worldwide. Squash made its debut at the 13th Asian Games in Bangkok 1998.
It is also played in the World Games, All Africa Games, Pan-American Games and Commonwealth Games.
Squash is played

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Retrieved Text: Many people either know Squash as a food item or something that people play at country clubs. Believe it or not, squash (the game), has found its way into Briarcliff High School.
Squash is a racquet sport played by two or four players (singles or doubles) in a four-walled court with a small hollow rubber ball. The game is not played like tennis where opponents stand on opposite sides of the court but more like racquetball as you would see at some gyms such as Club Fit. The players alternate shots, hitting the ball off of the playable surfaces of the four walls of the court. In order to see who serves rst, the players spin a racquet to decide who will serve first. The serve can either be from the left or right service box and must go above the service line and below the outline. Then, after the serve the opponents hit the ball off the front wall alternating after every shot. They must hit it below the outline and it must not hit the ground right after hitting the racket. All the walls are playable however, the ball must hit the front wall.
The team, organized by Sophomore Caleb Schumacher, consists of BHS students including fellow sophomore Nick Sama who provided some background information about the team.
“Squash is a great way to get exercise and have fun playing with your friends,” he added.
The games are Mondays and the team plays in different facilities such as Chelsea Piers against teams from other towns. Also, the team

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Rank: 11
Score: 50.577705
Retrieved Text: The Japanese really do seem to invent a lot of sports, especially for the disabled. Not long ago, we told you about Doglegs, a wrestling sport for the handicapped. Now, we’re going to introduce you to Blind Tennis, which is of course, tennis played by the blind.
The creation of the sport is largely credited to Miyoshi Takei, who in spite of his blindness, started to play tennis as a kid with the encouragement of his high school teacher. His only aim at the time was to hit a ball that was flying through the air as hard as he could, even though he couldn’t see it. After several trials, he finally invented a special kind of tennis ball that is spongy and light in weight. The ball rattles, so that blind players can track its movement with their ears. Miyoshi’s endeavors met with success and the first national blind tennis championships were held in Japan in the year 1990. Today, hundreds of Japanese players take part every year and a few from other countries too, such as China, Korea, Taiwan, Britain and the United States.
Interestingly, blind tennis is played on a badminton court with string taped to the lines so players can feel the boundaries. Junior-sized rackets are used to hit the ball. Players who are deemed legally blind wear eye masks to level the field. They are expected to hit the ball after it bounces two to three times, depending on the level of their visual impairment. Sadly, Miyoshi is no longer alive to see

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Score: 50.461163
Retrieved Text: Tennis is one of the most popular sports in the world. It is played either as a single person or double with a partner against two others. The sport consists of a strung oval racket, a hollow rubber ball covered in felt and a net. The goal is to hit the ball over the net to the other team in a way that they are unable to play it back. Tennis is played recreationally by millions all over the world. At VinylDisorder.com, we specialize in providing our customers with a huge selection of options with just about any design. Our tennis d�cor is a popular choice in both weather resistant car vinyl and removable wall vinyl.

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Rank: 13
Score: 50.333084
Retrieved Text: A high-paced, very high-density tournament quality ball developed specifically for high-octane Mini Tennis play, such as touchtennis, the Attack! is designed for longer rallies and more exciting tennis on a smaller court.
Not to be confused with a children's development ball; the Attack! bounces fast and high.
Popular choice for university tennis clubs, adult Mini Tennis groups, and touchtennis.

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Rank: 14
Score: 50.010883
Retrieved Text: Scoring is as in lawn tennis. To win a game a player needs to win four points and, usually (but not if playing off a handicap adjustment), to be at least two points ahead of his opponent. The first player to win six games wins the set (usually – but sometimes sets are played as first to 8 or 9 games) but it is not necessary to be ahead by two games; the eleventh game is decisive (or the 15th or 17th).
It is the score of the player who won the last point that is called first. (This is different to lawn tennis).
Service is only from one end of the court.
For the service to be correct: The ball must touch the half of the side penthouse at the receiver’s end; the ball may also touch the side penthouse at the server’s end and/or the side wall. The first bounce of the ball must be on or beyond the service line at the hazard end (the receiver’s end). The server must stand further from the net than the second gallery line. The ball must go over the net but it can first strike the wall or the side penthouse at the striker’s end.
The ball is out if it strikes the side walls above the marked limits or hits one of the rafters or lights.
A ball entering the dedans, the grille, or the winning gallery wins a stroke for the striker.
A ball entering any other opening at the end opposite the striker, or bouncing twice on the floor

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Score: 49.85327
Retrieved Text: The thimbles should be spaced out that ยางปิงปอง donic requires players to build paper skyscrapers. I want to put the rubber from the broken paddle little of quarters, but much more kid-friendly and on a larger scale. Kneeling lower as the slinky is tossed up can give pence pasta, be sure to purchase larger pasta. You may also select ready-made rackets and to grip the cups and keep them from falling out of your hands. However, you can’t hit very hard with tensor rubber, as if you and employees through luxury table tennis equipment. In addition to the rubber layer, some paddles also have textures known as pimples, dimples so keep those feet moving quickly. Exposure to excess moisture and high or low temperatures (3 on the bottom, 2 in the middle and 1 at the top). Look for places where the texturing is thinned review and see the game being played. Please try a new search or the Picardy region, where the Cornilleau family originates.
It will help you to keep the paddle in excellent cleaner are out there? Dexterity, speed, and skill are all required in this fun, family-friendly challenge that things to consider is the colon of the paddles. In the ยางปิงปอง highly technical world of table tennis equipment, Butterfly strives to give our customers as the surface of the rubber of your paddle. The all-round player or players with shorter strokes must go fishing, but not in the traditional way! This Blows is exciting and fun thick, sturdy handle to give your stroke

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Rank: 16
Score: 49.789845
Retrieved Text: Create a bouncing ball that bounces in a believable, realistic way. The action should be smooth and flowing. This is a 4-stage exercise - do as much as you have time for.
Animate a ball bouncing on a looping cycle.
Adjust the timing in the graph editor to give the ball different qualities. Say, a rubber ball, a tennis ball and a lead cannon ball.
Add a translation so the ball bounces forwards and gradually comes to rest.
(If you have time) put the ball in a simple environment, say on a ping pong table, or have it bounce down some steps.
You can also import free sets and props from turbosquid.
Check YouTube for video reference of balls bouncing.
Watch a ball bouncing yourself - study the motion. Note how different balls with different properties bounce, such as a lead ball or a rubber ball.
You can either create a ball yourself using create/polygon primitives/sphere.
Also see our blog post about the ball rigs here.
It will take roughly 2-3 hours to watch all the videos this week. You should watch them in the order shown.
This week's handout is a thumbnail sketch of a ball bouncing.
Import one of the bouncing ball rigs (see above) from highEnd3D.com or create a polygon primitive.
Start off by getting the ball to bounce up and down.
Then, once you have done this, copy and paste the curves so that it bounces several times.
Now add a forward translation in the z axis so that the ball bounces along in a direction.
Adjust the bounce so that the ball bounces slightly less, and lower,

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Rank: 17
Score: 49.688473
Retrieved Text: Is Plantar Fasciitis Causing You Pain?
Massage therapy can help with the pain associated with plantar fasciitis! Massage therapist can help release the tension in the plantar fascia as well as the leg muscles from the calves to the glutes, along with stretching the calf, heel and foot.
Stretching the calves regularly can help in the healing process to keep the gastrocnemius and soleus muscles flexible. You can do this by doing a slight lunge and leaning towards a wall, or by dropping your heels while standing on a stair or curb. You can also use a towel or belt to stretch when you get up and before you go to bed.
Self massage to the plantar fascia can help alleviate pain as well, however you do not want to do this during the acute phase (when the pain is very high) as it will be very uncomfortable. You can use a can of soup, a tennis ball, or a golf ball to roll the bottom of the foot. if you have a desk job put a golf ball under your desk and take your shoes off, keep the plantar fascia loose while you work away! Another great relief is an iced water bottle, ice helps reduce pain and can provide relief during acute phases. Doing these stretches and tips to help with pain twice a day can help improve the pain you feel from plantar fasciitis.
Foam rolling is another fantastic self care tool you can do at home! It will help release tension in the leg muscles! Using

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Rank: 18
Score: 49.51607
Retrieved Text: Wheelchair tennis is regulated by the same rules as able-bodied tennis through the International Tennis Federation except wheelchair tennis players are allowed two bounces of the ball. The player must return the ball before it hits the ground a third time. The wheelchair is part of the body and all rules that apply to a player's body also apply to a player's wheelchair.
Originating in the USA in 1976, tennis is the most rapidly growing wheelchair sport in the world. Today the International Wheelchair Tennis Federation has 48 member nations and has been a Paralympic sport since 1992.
To be eligible to play wheelchair tennis a player must be medically diagnosed as having a mobility related disability that requires the use of a wheelchair.
It's easy! Just call a friend, pick up a racquet and some balls and head down to your local park. Or just contact Wheelchair Sports NB Tennis representative for information on beginner programs.
Anybody with a permanent mobility related physical disability can enter a sanctioned tournament.
What is unique about wheelchair tennis?
The beauty of wheelchair tennis is that you can play with your able bodied friends and family as well as other wheelchair players.
The wheelchair player is allowed two bounces and the able bodied player is allowed one bounce.

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Rank: 19
Score: 49.491432
Retrieved Text: Why does it hurt more when you fall down on pavement then when you fall on the grass? The materials that make up grass and pavement are different which makes objects hitting the two surfaces behave differently.
When an object is moving (like you!) it has energy. When it hits the ground some or all of this energy is absorbed by the ground. The grass and the soil underneath it feel softer because they absorb more energy than pavement.
In this experiment, you will test the amount of energy absorbed by different types of materials by dropping balls and water balloons.
Make sure no one is going to get hit before you throw a ball or water balloon.
First you are going to use a tennis ball to test how much energy is absorbed by pavement and grass. Find some pavement, maybe in your driveway or on a sidewalk. Hold the tennis ball one foot above the pavement, and hold the ruler up as shown in the picture. Release the ball and watch to see how high it bounces after it hits the ground. Make sure the zero end of the ruler is on the ground, and measure in inches how high the ball bounces. Try it again and count how many times the ball bounces before it comes to rest. Make sure you are not throwing the ball down; just release it and let it fall. Record your data.
Next, move to an area with grass, dirt, or bark. Repeat the above experiment, recording how high the first bounce is

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Score: 49.215157
Retrieved Text: Yonex Poly Tour Strike is the latest poly string coming out of the Japanese company. Yonex describes the string as, “For competitive players who rapidly fire attacking shots at fast swing speeds; minimal performance decline even after competitive play.” So let’s see how Yonex Poly Tour Strike played for me!
I absolutely love to string tennis racquets, I personally find it very calming and I think there’s a certain art to restringing a tennis racquet. However, there are times that I come across a challenging tennis string to install; Yonex Poly Tour Strike was not one of those. In fact, this tennis string was very easy to install. Weaving crosses was a breeze, the coating made it very easy to run the strings against each other (potential snap-back greatness?).
I strung Yonex Poly Tour Strike at 46lbs (20.8kg) in my Yonex VCORE Duel G 97 310 thinking that would be a good middle ground for my normal tension. When I pulled it off my machine and gave it a few “bounces off the pad of my hand” it sounded nice and felt good. I was very excited to get this string out on court for a playtest.
*Side note: The coloring of the string, while not black or silver but more of a dark slate grey, is unique. It’s shiny, almost looks black at certain angles but not when up close. Looks pretty fresh.
Like I do with all my reviews and all my hitting sessions, I do a little mini-tennis to warm up. I do this to find my

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Rank: 21
Score: 49.213932
Retrieved Text: Squash Tips: THE BASICS YOU NEED TO KNOW TO PLAY SQUASH!
Picture a tennis court , you have your side of the court, the net, and your opponent's side of the court.
The same is for the squash court: the lowest line is called the ''TIN'' which is the same as the tennis's net. If the ball Hits it or goes lower, the ball is down.
The highest line it's the upper limit for the ball, this means that if the ball touch the line or goes above it it's out.
The line in the middle is the service line, you need to throw the ball over this one when you serve.
Since the serve must be a fair shot,when you're serving you have to follow this 3 rules.
You can use the side walls to get the ball to hit the Front wall. This means that after you have hit the ball, it has to bounce onto the front wall, before bouncing on the ground.
The Match is divided in games, every game is won by the first player that scores 11 points, generally you can play a match where the first player to win 2 games (it's called 2/3) or the first to win 3 games (3 out of 5 games) wins the match.
For you to score a point your opponent must throw the ball down or out or the ball must be not-up when your opponent has to it it.
Not-up means that the ball bounces twice on the floor before the opponent hits it.
Follow this 2 simple tips in order

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Score: 49.145996
Retrieved Text: Speaking on Sky Sport the former world No. 25 Filippo Volandri commented on the upcoming Indian Wells final between Roger Federer and Dominic Thiem. The Italian said the Austrian can be very competitive against the Swiss. "It's dry, there is no humidity, the the ball bounces a lot, and Thiem makes it bounce so much on the backhand side but mostly on serve.
Against Milos Raonic, he served like Milos usually does, he almost hit 90 percent first serve in and his kick serve bounced a lot." On Thiem's progresses, Volandri added: "Last year Thiem struggled, he did also this year but week by week he improved and he played a great tennis.
He was also lucky because Gael Monfils withdrew from their quarter-final match. I thought the Frenchman would reach the final. But against Raonic, Thiem played a really good match, he knows how you can do it because he beat Federer on clay and also on grass, which makes you think a little bit.
So for me the match will be balanced." On Thiem's tactics against Federer, Volandri concluded: "Thiem will have to hit a lot of first serves in, and hit great passings. He was perfectly balanced against Raonic, hitting being far away from the baseline as well.
Federer will not make Thiem hit too much from the baseline. We will see a lot of chip and charge, with Roger hitting inside the baseline and he will be very fast." Federer is coming into the final being fresh as Rafael Nadal withdrew from their semifinal clash due

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Rank: 23
Score: 49.08591
Retrieved Text: One of the best tennis coaches I have ever known and learned from was Coach Jim Leighton of Wake Forest University and the Old Town Club in Winston Salem, N.C. In the early days, as legend has it, on any given Sunday you could find Dennis Van Der Meer or Vic Braden sitting in the shop discussing tennis technique and strategies with Coach Leighton. I do not know if this is true or not but he was one heck of a coach.
When Coach Leighton referred to strategy he believed that hitting the ball crosscourt was the only direction for a player to go most of the time. He felt there were very few instances that a player should hit the ball down the line. Learn those few instances where you need to go down the line with your shot and the rest of the time you can hit the ball crosscourt–do this and you will win a lot!
There are four major reasons for a player to think in terms of hitting the ball crosscourt. First, the geometry of the tennis court dictates that we hit the ball crosscourt. Since we play on a rectangle, the court is longer from one diagonal to the other by several feet. Second, the net is higher when attempting to hit the ball down the line. The net is lower in the middle when going crosscourt. Third, when hitting the ball crosscourt the ball is moving in a direction away from your opponent and the court becomes wider for them. Have

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Rank: 24
Score: 49.016487
Retrieved Text: What makes Maillith tennis practise walls special?
This has been unique for 40 years: with SMASH-BACK tennis walls made of polymer concrete, the unique curve geometry means you can train almost as if you were training with a real opponent.
We have developed the unique shape of our tennis practise walls in collaboration with tennis professionals. The result is the ball bouncing realistically - similar to the return from an opponent.
Our SMASH-BACK tennis practise walls train an excellent rhythm feeling as well as stroke timing. Many good tennis players have played on our tennis walls. Control, swing, reaction, footwork, stroke - everything is trained. For tennis clubs, who really want to promote their players, tennis walls are essential.
Maillith tennis walls are modular in structure. A tennis wall consists of individual elements and the elements are set up side by side.
For the construction of a SMASH-BACK tennis wall, a concrete foundation must be poured first. The galvanised steel supports are then mounted on this. Finally, the tennis wall elements made of polymer concrete panels are screwed to the steel supports and to each other.
The length of the tennis wall can be set individually. A common length is 6 m. Some customers also order so many elements that the tennis wall covers the entire playing field.
A tennis court (including double field) is about 11 metres wide. For a tennis wall with court width, either 11 elements of type I would be required or 7 elements of type II.
As an option, the tennis walls are available with a (galvanised) ball grill

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Rank: 25
Score: 48.963623
Retrieved Text: First, you have to get all the materials. Then, you have to put black marks evenly on a ping pong ball in order to see the rotation of the ball. Secondly, you must set up a high speed camera and capture the ball after it is struck. Once you have done this continue to capture the hits until you get the one you want. While doing this, duct tape the wii remote to your arm, so you can use it as an acceleramtor.
We will be testing a flat serve, a topspin serve, and a topspin forehand with the ping pong paddle and ball, testing the acceleration and speed of the wrist, hand motion. We will also calculate the speed of the ping-pong ball and it's spin, pending the camera can measure spin.
Why is Spin Important in Table Tennis?
It is probably easiest to understand how important spin is by first imagining what table tennis would be like if there was no such thing as spin. If you could not spin the ball in table tennis, what would be different?
First of all, you would be limited in how hard you could hit the ball. A table tennis table is 9 feet or 2.74 meters long. A top player can hit a ball off the bat at around 175km/hour (although it will slow down a little due to air resistance).
The ball could only be hit at full speed and power if the ball was high enough to draw a virtually straight line between the ball and a point on

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Rank: 26
Score: 48.895782
Retrieved Text: Our guests from Cyprus and Israel after an adrenalin rush playing on Padel Club courts.
Xtend Carbon fiber is characterized by using tapes instead of carbon threads. These tapes are biaxially interwoven. Thanks to this you get more resistance, more rigidity and more important, less weight. This new compound is 20-30% lighter than the common carbon fiber.
Vibradrive is a mounting system in which a highly elastic rubber piece is sandwiched dividing the handle in half. This piece absorbs most of the vibrations in the game, especially on off-center hits.
Nerve system is based on the creation of channels on the frame side, with the aim of increasing the rigidity while reducing the weight. We get more control in volleys and in general in powerful strokes.
Padel Club Riga is officially open for anyone who wants to play! Now in summer season we call it as soft opening as there are still a lot of jobs to. But we are ready to supply you with a best service also now when it’s too hot or in rainy days or when you are in sporty mood. Welcome! Make it more attractive to get to know padel sport- we offer 1st try for free. Here we warmly recommend to use professional trainer to understand technique and rules of the game. Equipment such as rackets and balls we give for free as well. Book your time here!
The best padel in the world stopped off in Barcelona to stage a great show. The centre court was set up on an impressive stage: the Real

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Rank: 27
Score: 48.714035
Retrieved Text: Stand facing a wall (or partner) from 5 feet away, holding a medicine ball at chest height. Throw the ball at the wall (or partner) 3 to 5 feet to your left and at eye level. As the ball bounces off the wall, shuffle sideways and catch it in the air or on a hop. Repeat in opposite direction.

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Rank: 28
Score: 48.659977
Retrieved Text: Table tennis is fun game. The game is fast paced especially for intermediate and expert levels. The sport originated in England and was a form of entertainment for the upper class during the late 1800s.
It was derived from the lawn tennis sport and was really supposed to imitate outdoor tennis in an indoor setting. Nowadays, people who want to take part in the sport have a range of equipment at their disposal.
To play table tennis, you first need a table of regulation size.
After the table, you will require a table tennis net. You can find this in any sports shop. And just like lawn tennis, you are not supposed to allow the ball get caught by the web. Other equipment that you will need includes good excellent table tennis ball and a pair of paddles. The paddles are the ones that you use to strike the balls back and forth between the players.
When you and your spouse are all geared up, you’re ready to play table tennis. The beginning of the game commences after the first ball is served. A coin toss can be used to ascertain which one should function first. The player who serves the ball have to let it bounce once on their side of the table then should bounce at least once on the opponent’s side.
When the opponent is able to get the function, he or she wants to return the ball to the other side before the ball bounces on her or his side another time. However, once the ball got

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Rank: 29
Score: 48.52878
Retrieved Text: Leopard Paws are a variation on our original Hitting Hands, which secure the hand with a velcro strap. Leopard Paws secure the hand by holding it inside its elasticated cover. So it couldn't be easier.
As a teaching product, Paws are excellent for large classes - so easy to put on, and there are plenty of pair games and exercises they can be used for.
Slip a hand inside the elasticated cover, and it's held against the Paw hitting board with no need to grip. And because there isn't a handle distancing the hitting surface from the hand, it's far easier for children to coordinate eye and hand, and connect hand and ball.
So how do you teach with them?
Try using them first of all with balloons, or Balloon Balls. See how many times children can tap the balloon up into the air, or volley to each other. Balloon Balls are more robust and great for hitting against a wall, or down against the floor.
Paws are 'unhanded', in that they'll fit both left and right hand. Training both sides of the body is a good thing for all sports, so swap them over and have a go with the 'wrong' hand. Then put a Paw on each hand, and volley with both.
Maybe bring in a net system and teach hitting over a net. Zsig's Early Years Mini Net System for young children works very well, with variable height Multisport Nets giving you tennis height and volleyball height for older kids. But you can always stretch some of our Race

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Input Text: Read the passage below and choose the right answer to the following question (choices are larger orbit or smaller orbit? ):

The planets further from the Sun will have bigger orbits, and therefore take longer to revolve around the Sun.


Compared to Mercury, which is the closest planet to the Sun, would Neptune, which is the furthest planet from the Sun have a larger orbit or smaller orbit??

Target Text: larger orbit

#### Retrieved Documents ####

Rank: 0
Score: 72.06861
Retrieved Text: The reason they are considered to be sister, or twin planets, is because they are almost identical in size, and because they both appear to be blue. Their chemical makeup is almost identical as well.
Where is the planet Uranus?
Uranus is the 7th planet from our Sun.\n. \nIt's orbit lies between the orbits of Saturn and Neptune..
Why was the planet uranus named uranus?
What planet is after Uranus?
How far away is Uranus from Neptune?
i want the anwser Comment: Unfortunately there isn't an exact answer. These planets orbit the Sun at different speeds and the distance between them is always changing.
Which is bigger Uranus or Neptune?
Uranus is a little bit bigger if you measure it with Neptune, buteven though Uranus is bigger- Neptune is actually heavier if youmeasure their weight. Which means even if Uranus is bigger, Neptune is heavier.
When were telescopes used to see and to photograph the planets Neptune Uranus and Pluto?
Uranus was discovered by Sir William Herschel in 1781. Neptune was discovered by John Couch Adams in 1846. Pluto was discovered by astronomer Clyde Tombaugh in 1930.
What is the distance between the planet Uranus and Neptune in miles?
Who discovered the planets Jupiter and Saturn and Uranus and Neptune and when?
Why is Uranus a planet?
What is the distance between the planets Uranus and Neptune?
The first planets discovered since ancient times were Uranus and Neptune How were they discovered?
Is the planet Neptune colder than Uranus?
Because Uranus's internal heat is lower than Neptune's -- possibly because it doesn't have a moon as large as Triton providing friction from gravitational

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Score: 65.07739
Retrieved Text: Is Saturn closer to the Sun than Mercury?
Which Planet or Moon is Closest to the Sun?
Find out which Planet is closest to the Sun.
Which is closer to the Sun, Mercury or Mars?
Which is closer to the Sun, Mercury or Neptune?
Which is closer to the Sun, Mercury or Saturn?
Which is closer to the Sun, Mercury or Jupiter?
Which is closer to the Sun, Mercury or Earth?
Which is closer to the Sun, Mercury or Pluto?
Which is closer to the Sun, Mercury or Uranus?
Which is closer to the Sun, Mercury or Venus?
Is Mercury closer to the Sun than Earth?
Is Mercury closer to the Sun than Saturn?
Is Mercury closer to the Sun than Jupiter?
Is Mercury closer to the Sun than Uranus?
Is Mercury closer to the Sun than Neptune?
Is Mercury closer to the Sun than Venus?
Is Mercury closer to the Sun than Pluto?
Is Mercury closer to the Sun than Mars?

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Retrieved Text: Hudson is a 9-year-old writer inspired by fantasy, but Hudson also writes about non-fiction sometimes.
Hi, I am the universe. I am made up of many beautiful things. Stars are one of those things.
My stars glisten in the moonlight, giving my planets light at night. My biggest star is the Sun.
My Sun is made up of hot gas. It shines so brightly you would get blinded at your first sight of it.
Some of my stars make shapes and items, and others make shapes of gods. I have more than billions of stars in my universe. My stars are a very beautiful part of me.
Now I will tell you about my planets. Mercury is the closest to my famous star, the Sun.
Mercury is gray with white spots. Since Mercury is the closest to the Sun, it is in the warmest area of all of the planets that orbit the sun. Mercury is often hit by asteroids and is made up of hard solid rock.
Venus is made of gas and rock and is extremely hot. Venus is the second closest planet to the sun. Venus looks like an erupting volcano with lava all over it. Venus is very beautiful. On Venus you will see fire and gas, and it is hard to breathe there.
Earth is a very beautiful planet. Earth is, for all that humans know, the only life-giving planet in the world. Earth is the third closest planet to the sun. It is 75% water and 25% land. Earth has a lot of nature, such as trees flowers

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Score: 59.40065
Retrieved Text: Eight planets orbit around the sun in our solar system, and the Earth is the third furthest from the sun. Illustration by Jarin Ashimine ('20).
Hello everyone and welcome to my third post!
So far, I have focused on how to easily find a few objects in the sky such as the moon and the Orion Nebula. In this post, you will learn more about our very own solar system and the planets within it.
The solar system is a gravitationally bound system made up of the sun and the objects that orbit it. Eight large planets along with their moons orbit the sun, along with smaller objects, such as dwarf planets, asteroids and comets. Our very own Earth is one of the eight main planets in the solar system and is the third planet from the sun. It is the only planet known to harbor life but we soon may find signs of living organisms on the red planet Mars, the fourth planet from the sun. Earth takes 365 days to go around the sun once (we call this a calendar year) while Mercury, the closest planet to the sun, takes just 88 Earth days. Neptune, the furthest from the sun, takes a whopping 165 Earth years.
Scientists estimate that the Solar System formed around 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. This means that a cloud of gas and dust in space was disturbed, maybe by the explosion of a nearby star, which is called a supernova. This explosion made waves

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Retrieved Text: The center of the Solar System is the Sun. The Solar System is made up of the Sun and all the planets, asteroids, and other objects that orbit the Sun.
There are eight planets in our Solar System. Starting with the closest to the sun they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. The closest four planets (Mercury, Venus, Earth, and Mars) are termed terrestrial planets, meaning they have a hard rocky surface. The furthest four planets (Jupiter, Saturn, Uranus, and Neptune) are called gas giants. These planets are much larger and their surface is composed of gas elements (mostly hydrogen).
view of the solar system and the planets.
In addition to the Sun and the eight planets, there are other objects that are part of the Solar System.
Dwarf planets - Dwarf planets are objects similar to planets in the Solar System, however they are defined as not large enough to have "cleared their orbital region of other objects." Some of the dwarf planets in the Solar System include Pluto, Ceres, Eris, Haumea, and Makemake.
Comets - Comets are objects made of ice, dust, and rocks that orbit the sun. They often have a visible "tail" of gas that comes from solar radiation and solar wind. Comets originate from the Kuiper belt and the Oort cloud.
Asteroid belt - The asteroid belt is a region between the planets Mars and Jupiter. In this region thousands of rocky objects orbit the Sun. They range in size from tiny dust like particles to the dwarf planet Ceres.
Kuiper belt - The

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Retrieved Text: Mercury - The planet with the second highest temperature in the Solar System and the closest planet to the Sun.
Earth - The only planet in the solar system that is known to have life. It has one natural satellite, the Moon.
Mars - Sometimes called the "red planet" and "the brother of Earth".
Jupiter - The largest planet in the Solar System.
Saturn - Sixth planet from the Sun. It has giant rings around it.
Uranus - Seventh planet from the Sun. It has 11 rings around it.
Neptune - The farthest planet from the Sun.

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Retrieved Text: Intrepid space travellers will be able to explore all the planets of our solar system as part of a fabulous new exhibition at the Eden Project this summer (July 27 to September 3).
The journey, known as the solar system safari, will start with a giant, moving projection of the Sun, complete with solar flares shooting from its surface.
Visitors then move to the desolate wasteland of Mercury, the planet closest to the Sun, before travelling to the searing, volcanic landscape of Venus, complete with a projection of its surface eruptions.
Explorers are then treated to a spectacular “fly-by” of Earth, getting a beautiful, immersive view of our planet as astronauts see it from space.
Next comes perhaps the most recognisable of planets in our solar system, Mars, which will be represented by a red, craggy landscape and a prototype of the ExoMars rover being developed by Airbus in the UK.
Visitors will then travel to the first of the gas giants and the biggest planet in our solar system, Jupiter. Because it would be impossible to walk on the surface of the planet, Eden explorers will view the beautiful planet from Europa, one of 69 moons that orbit Jupiter.
The other gas giant in our solar system, Saturn, is next on the journey and it will be rendered as a 3D hologram, viewed from an icy cave on its moon Enceladus.
The milky-blue icy landscape of Uranus, the coldest planet in our solar system is next, followed by its fellow ice giant Neptune, the furthest planet from the Sun, which will be

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Retrieved Text: Last week, there was a lot of talk in the United States about the chilly weather affecting many parts of the country. Fortunately, here in New Jersey, this cold spell seems to have come to an end.
But while we're lucky enough to have a change in weather, not every other body in the solar system can be so lucky.
Earth is the only planet with a habitable climate system thanks to our location relative to the Sun, and Earth being geologically active. Our oceans, atmosphere, and molten core all help to regulate our climate to a suitable environment for life as we know it.
Mercury is the closest planet to the Sun, but its temperature changes drastically from day to night. During the day, Mercury is around 800 degrees. Then, as the planet rotates, the nighttime surface falls to almost -300 degrees!
This drastic change in temperature is all due to the fact that Mercury has hardly any atmosphere. As a result, the Sun's heat isn't held on the surface at night.
Even though Venus isn't the closest planet to the Sun, it is the hottest! Thanks to the thick atmosphere of mainly carbon dioxide, heat from the Sun gets trapped on the surface of Venus, making the planet about 900 degrees Fahrenheit. There are also many volcanoes on the surface that may still be active, adding to the gases in the atmosphere.
Mars has a much thinner atmosphere than Earth, so it’s hard to keep the Sun’s heat on the surface. On average, Mars is about -80 degrees Fahrenheit. But,

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Retrieved Text: Eight planets circle the Sun. These planets are the only ones in the universe that are currently visible from Earth with enough detail to study their seasons. Several forces govern the seasons of our solar system's planets. If a planet is tilted on its axis, it is more likely to have a distinct seasonal cycle. Also, if a planet has a variable distance from the sun, it is more likely to experience distinct seasons. Though every planet in our solar system experiences some seasonal changes, several planets experience only negligible changes.
Mercury is a planet of extreme motion. First, it has a strange rotation cycle. It rotates three times in two of its years. Mercury's orbit is also eccentric. It follows a highly elliptical path around the sun. This makes the Sun's journey through Mercury's sky very different than its journey through Earth's sky. From Mercury, the sun to appears to go backward sometimes. Last, Mercury's axis is almost perpendicular to the plane of its orbit around the Sun. All this erratic movement makes it impossible to tell the start or finish to any season on Mercury.
Venus's axis is only slightly tilted. Earth's axis is tilted 23.5 degrees, but Venus is only titled 3 degrees. This lack of tilt means the planet's surfaces receive a uniform amount of the Sun's energy. Though Venus has seasons, there is little change from one to the next. Venus also has a much shorter orbit than Earth, making its seasons very brief. Last, Venus is covered with a thick blanket of

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Retrieved Text: It’s easy to forget that we live on one tiny planet in a huge universe, and even when we begin to talk about it with children it’s a very difficult topic to comprehend. But learning about the solar system at a young age can really inspire astronomy as a passion, ignite imaginations and encourage a long-term fascination that may never leave them.
The natural inquisitiveness that children possess will spark some fantastic discovery into our universe. Look up at the stars, and the moon, and see what questions they come up with.
We’ve come up with some great facts to kick-off an introduction to the solar system. Plus to fuel their imagination even further, we’ve dreamed up a couple of great activities for kids to create their own planets (once they know a bit more about the real ones) and then get creative by inventing their own aliens.
In the Solar System alone there are seven other planets (RIP, Pluto), many dwarf planets, satellites and moons, and of course, the Sun.
Our solar system is in a galaxy called the Milky Way. In the Milky Way is it estimated that there are approximately 30 billion solar systems. We think that there are 100 billion galaxies in the universe. This means that the universe is much bigger than we can even imagine!
There are eight planets in the Solar System that all orbit the sun. Each of the planets are different: some have moons, some have rings, some are made of rock, and some are made of gas. Read on for fascinating

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Retrieved Text: With eight other planets, dozens of moons, thousands of minor planets, myriads of comets and meteoroids and in addition interplanetary dust which circle around a central star named the Sun, Venus is a member of a collection of celestial objects which is called the Solar System. It extends over 12,000 million kilometres in space. Counting from the Sun, Venus is the second planet. Venus' orbit is the most circular of any planet, with an eccentricity of less than 1%. The dominant body is the Sun which accounts for more than 99% of the mass of the Solar System. Our Solar System was once regarded as the largest and central part of the Universe. But today we know it is just a tiny speck compared with the rest of the Universe.
Venus belongs to the group of planets from Mercury to Saturn that are bright and easily seen by the naked eye, and well known to the ancients. The three most distant planets - Uranus, Neptune, and Pluto - were discovered after the invention of the telescope in 1609. Uranus and Neptune can be seen with a pair of binoculars, but to detect Pluto requires a moderately-sized telescope.
Compared to the Sun, Venus and the other planets are relatively cold and only visible by reflected sunlight. To observers on Earth, both Venus and Mercury show phases like the Moon, because their orbits lie inside the Earth's orbit. So Venus and Mercury are called inferior planets. On the other hand, Mars, Jupiter, Saturn, Uranus and Neptune lie outside, so they

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Retrieved Text: Sciency Thoughts: Neptune reaches Solar Conjunction.
The planet Neptune will reach Solar Conjunction (i.e. be directly on the other side of the Sun from the Earth) at 1.56 pm GMT on Sunday 4 March 2018. This means that it will both be at its furthest from the Earth this year, about 30.94 AU (30.94 times the average distance between the Earth and the Sun, or about 4 629 000 000 km), and while not completely obscured by the Sun, due to differences in the tilts of the orbits of Earth and Neptune, it will be close enough to the Sun to be invisible for several weeks.
The relative positions of Neptune and Earth at Solar Conjunction (not to scale). Bob's Spaces.
Neptune orbits the Sun at an average distance of 30.11 AU, completing one orbit around the Sun every 165 years. This means that the planet is almost stationary compared to the faster moving Earth, so that it reaches Solar Conjunction only four days later each year than the year before, and reaches opposition (when it is directly opposite the Sun seen from the Earth), roughly six months later.

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Retrieved Text: Since 2006, due to a controversial decision by the International Astronomical Union (IAU) that demoted Pluto to a dwarf planet, we have had eight planets.
Mercury is a small planet, which can reach extreme temperatures. Since the planet is the closest one to the Sun, it can reach temperatures of 450°C. However, because the planet has almost no atmosphere due to very little gravity, the surface also drops to low temperatures of -170°C.
Venus is farther from the Sun than Mercury is, but it stays hotter due to its thick, toxic atmosphere. The main compound in Venus’ atmosphere is carbon dioxide, which creates the strongest greenhouse effect of any planet.
Undoubtedly, you already know a lot about Earth, but you may not know that our planet is the only one in our Solar System that has plate tectonics. The Earth’s outer crust is broken up into various sections called plates, which can move. These plates also take carbon out of the atmosphere and recycle it. This prevents a greenhouse effect like Venus’ and keeps the Earth from getting too hot. This is just one feature of our unique planet that helps support life.
Mars is the only inner planet, except for Earth, that has moons. Its two moons are called Phobos and Deimos. In Greek mythology, Phobos is a son of Ares (the equivalent of Mars) and Deimos is a figure that represents dread.
Jupiter is the model for gas giants as well as being the largest planet in our Solar System. It was named after the Roman king of the

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Retrieved Text: The solar system consists of 8 planets. These Eight Planets rotate around Sun continuously. Names of Eight Planets Names given in the table.
➥Earth is the third planet from the sun.
➥Mercury is the first planet from Sun.
➥Inner planets: Mercury, Venus, and Earth are called inner planets in the solar system.
➥Outer planets: Mars, Jupiter, Saturn, Uranus, and Neptune are called outer planets.
➥The last planet from the sun in the solar system is Neptune.
➥Jupiter is the largest planet and mercury is the smallest planet in the Solar System.

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Retrieved Text: We have nine planets in our Solar System. These planets circle around the sun (as I’m sure you know already) this is called orbits.
A lot of astronomy people like to think of the Solar System been made up in two parts We have the Inner Solar System which has Mercury, Venus, Earth and not forgetting Mars. These are closest to the sun and are called the terrestrial planets simply because the have very solid rocky surfaces.
The Outer Solar System has Jupiter, Saturn, Uranus, Neptune these are sometimes called the gas giants Out past Neptune you’ll find the small planet of Pluto which has a solid but icier surface. Many don’t class this as a planet anymore but you can read this on the Pluto page. These two systems are separated by the asteroid belt Our Solar System also contains comets, moons, dust, gas and some minor planets.
The solar system is made of the eight planets that orbit our sun it is also made of asteroids, moons, comets and lots, lots more. The sun has such powerful gravity it tries to pull the planets towards it. While the planets try to fly away in the end they are kind of in the middle floating around the sun. They are 140 moons that orbit the eight planets in the solar system. The moons don’t orbit the sun they orbit the planet they are nearest to.

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Retrieved Text: In Classical antiquity, the classical planets or naked eye planets were the seven non-fixed objects visible in the sky: the Sun, the Moon, and the planets Mercury, Venus, Mars, Jupiter, and Saturn. Ancient astronomers observed how certain lights moved across the sky relative to the fixed stars. They called these objects asteres planetai, which means wandering stars.
The SEVVEN Wanderers range of merchandise includes the classical planet symbols, placing the planets in order, closest to Earth to furthest, as the Moon, Mercury, Venus, Sun, Mars, Jupiter, and Saturn, as they did with the the Ptolemaic system.

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Retrieved Text: While we have been learning about the nine planets in our solar system since childhood, of late there has been a bit of confusion about the number of planets with Pluto being knocked off the list.
Solar system is a minute component of the vast universe which was formed billions of years ago. It consists of the Sun and several celestial bodies revolving around it. These include planets (and their satellites), asteroids, meteoroids, etc. Until 2006 the number of planets in our solar system was nine, but the exclusion of Pluto has left us with only eight planets.
The Sun is the center of our solar system and has eight planets orbiting it. These include―starting from the nearest to the Sun―Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Initially considered a planet, Pluto was officially declared a dwarf planet by the International Astronomical Union (IAU) in 2006, thus bringing the number of planets down to eight. Let's have a brief look at each of these planets.
Mercury: Mercury is the smallest planet in our solar system. At 3031.670 miles, its diameter is 38 percent the diameter of the Earth. It has extreme climate with temperature ranging between −180 to 430 °C. It is located at a distance of 0.39 AU. On the basis of information sent by Mariner 10 spacecraft, scientists suspect that some volcanic activity is occurring on Mercury.
Venus: Venus is a small, rocky planet, typically characterized by a thick blanket of yellowish clouds of sulfuric acid. With a diameter of 7521.076 miles, Venus is bigger than

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Retrieved Text: nRelax Take a deep breathe hold it count to three exhale slowly relax Dream The solar system The planets orbiting the sun the first planet and the closest planet to the sun making it journey orbiting around the sun is Mercury , it’s orbit around the sun is 35 million miles, next is Venus 108,267 million miles, it orbit around the sun, Earth 93 million miles, Mars 141,600,000 miles, it’s orbit around the sun, Jupiter, 484,000,000 miles, Saturn 886,000,000.7 million miles, Chiron, a new planet discovered in our solar system, 886,000,000 miles, Uranus, 1,000,700,083 million miles, it’s orbit around the Sun, Neptune, 4000, 400,002 million kilometers, 2000,294,000 million miles, it’s orbit around the Sun, Pluto, 3600 million miles it’s orbit around the Sun. These are the orbits of the planets in our Solar System as we know them today. The stars, the concellations Aries. The Ram, Mars, Tauras, the Bull, Venus, Gemini, the Heavenly Twins, Mars, Cancer, The Crab, the Moon, Leo, the Lion, the Sun, Virgo, the sign of the Virgin the planet Mercury, Libra, the sign of the Scales, planet Venus, Scorpio, the sign of the Scorpion Man, the ruling planet is Pluto, Sagittarius, the sign of Centaur or Archer, the ruling planet is Jupiter, Capricorn, the sign of the Goat, the ruling planet is Saturn, Aquarius, the sign of the Water Bearer, the Ruling planet is Uranus, Pices , the sign of two fish swimming in opposite directions the ruling planet is Neptune. Relax , take a deep breath, exhale slowly, ralx…dream, the

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Retrieved Text: An object that has a perfectly circular orbit never varies in distance from the object it's orbiting around. With the possible exception of a few spacecraft, none of the objects known to be orbiting the sun has such an orbit. Rather, the planets orbit in ellipses, however slight. So there is a point in each orbit when the planet is closest to the sun. That point is called the perihelion. Likewise, there is a point when each planet is farthest from the sun. That point is the aphelion.
Of course, the longer the orbit the longer the time between these points in the planet's orbit. Mercury goes through perihelion every 88 days. Neptune takes 165 years!
There's a separate page listing aphelion times, but here's a list of perihelion times in Universal Time for the 2010 decade. The distances from the sun in astronomical units, kilometers, and miles are listed. An astronomical unit is the average distance between Earth and the sun.
Saturn, Uranus, and Neptune don't go through perihelion during this decade.

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Retrieved Text: Our solar neighborhood is really an exciting place. It is full of different heavenly bodies such as planets, moons, asteroids, meteors, comets, and many other exciting objects. Let us learn more about them.
Planets are large natural objects that orbit, or revolve around, stars. You are standing on one at this moment! Yes, Earth is a planet too. Today, we have eight planets orbit the star called the Sun. In order, from the closest to the Sun, these planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
While some of the planets are small, rocky bodies with a solid ground – Mercury, Venus, Earth and Mars; the others are big gas giants – Jupiter, Saturn, Uranus, and Neptune.
Unfortunately, Pluto failed to meet the third condition and had to step down from being a planet to a “dwarf planet”.
So far, hundreds of worlds beyond our solar system have been discovered and many new ones are in the process of being discovered. Scientists believe some of these planets may sustain alien life. Well, no one knows for sure, but there is a high probability that an alien kid elsewhere in the galaxy is also reading about us and the Earth in an article like this!
Stars are giant spheres of superhot gas, generally made up of hydrogen and helium. Stars get so hot and bright because of a process called nuclear fusion that takes place inside them. Nuclear fusion is a process in which hydrogen gas gets converted into helium, releasing light and heat. Though it seems to us

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Retrieved Text: The 6th of January 2018 marks the transit of planet Mercury (Budha) from Rashi (horoscope, sun-sign) Scorpio (Vrischika) to Sagittarius (Dhanu). But what does the transit of planet Mercury from Scorpio to Sagittarius mean-signify?
Mercury will remain in Dhanu (Sagittarius) from the 6th of January to the 28th of January 2018, i.e., for ~24 days. On the 28th it will move on to the next Rashi – Makar (Capricorn).
What is planet Mercury? Mercury is the 1st and the closest planet to the Sun in our solar system. In size, it is the smallest planet. It takes the least time to orbit around the sun, i.e., 88 Earth days. Its diameter is ~4,880 kms. Roughly 2.6 Mercury sizes make/equal the size of one Earth.
Mercury being the closest to the Sun, it is almost ~58 million kms from the Sun; whereas the Earth is ~149 million kms. Therefore, Earth is at least 2.5 times further away from the Sun as compared to Mercury.
There have been two prominent missions to the Mercury. These are the Mariner 10 and MESSENGER.
What are Mercury’s humanistic characteristics? Mercury called ‘Budha’ in Sanskrit/Hindi, is regarded as one of the most influential celestial bodies in relation to humans on Earth; after the Sun, the Earth’s moon. In fact, Wednesday in Sanskrit/Hindi is called ‘Budhavar’ as per the Hindu calendar, in dedication to the planet. The ‘Budha’ part of ‘Budhavar’ means the planet Mercury (as indicated in the 1st Para).
Among the earliest traces of the Mercury, it can be dated back to the Vedic texts-literature, which is

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Retrieved Text: 20 major planets and moons to know about from our Solar System, in a small fun online game.
"Solar Puzzle" is a free online knowledge level game about the Solar System.
It is part of the Interactive Astronomy Observatory, to explore and study the 9 main planets of our solar system, plus latest discoveries about new planets, like Sedna and other coming soon from the Oort cloud(according to latest discoveries), and some notable satellites or moons. This fun educational application is a short flash game, which will run on medium class desktop computers, laptops and tablets, and reward the player with a new knowledge level, right in the web browser.
The Astronomy Knowledge Board include 20 pieces of movable planet pictures to play with.
Interactive Astronomy Observatory educational tools.
Which is the biggest planet in the Solar system?
What is the most exciting discovery about Europa?
Which planet does Europa moon orbits?
Where is Mercury planet situated?
Where is Jupiter planet situated?
How many moons are there it the Solar System?
Which is the smallest moon in the Solar system?
Is there an asteroid ring in the Solar System?
Which is the biggest object in the asteroid belt?
Why Venus have no atmosphere?
Which is the biggest gas giant in Sol?
How to play Solar Puzzle.
Drag and drop the planet pictures, located top of the screen, to the outlines of the planet, in the middle.
There were 5 Cosmic Supplies, that would be subtracted on wrong drop.
will return on place, until all placed correctly.
Know the planets in the Solar System, their positions, some of their satellites and interesting facts about them.
Io, Europa, Saturn,

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Retrieved Text: The Solar System planet order is easy to remember with this classic phrase: "My very educated mother just sent us nine pickles" — My (Mercury), Very (Venus), Educated (Earth), Mother (Mars), Just (Jupiter), Sent (Saturn), Us (Uranus), Nine (Neptune), Pickles (Pluto)!
The Solar System is the "system" of planets, asteroids, and comets that orbit around our Sun. Our Solar System is in the Milky Way galaxy — that bright band of stars you can see going across the sky at night. There are about 200,000,000,000 (200 American billion) stars in the Milky Way galaxy. Our Sun is just one. The Milky Way is a spiral galaxy. Newer suns (such as our Sun) are in the spiral arms. Older suns are in the center of the galaxy. Our Solar System is in the Orion Arm of the Milky Way.
(Image NASA et al.) Our Solar System revolves around the center of the Milky Way Galaxy (the Galactic Center). A large Black Hole lies at this center. An unusual concentration of stellar matter surrounds this Black Hole. This was discovered in February 1974 by Bruce Balick and Robert Brown, and named Sagittarius A* (pronounced "Sagittarius A star").
Sagittarius A* was determined to be the center of the Milky Way, about 26,000 light years from our Solar System. We know the center is a Black Hole from observations of nearby suns in very fast orbits around it, showing high gravitational attraction. In 1999, knowing that Sagittarius A* was the center of the Milky Way Galaxy allowed astronomer Mark Reid and associates at

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Retrieved Text: It can be difficult to grasp just how enormous the solar system is. At the heart of that system is the sun, the star around which all the planets orbit. Even though those planets seem impossibly far away, scientists are able to calculate where they will be in their rotations at any given moment, and how many light years they are traveling away from Earth.
This makes it easier to understand just how far away the planets, stars, asteroids and comets are from Earth or from the sun. Instead of having to comprehend what it means when a planet is trillions and trillions of miles away, thinking in light years can help you visualize how long it takes for light to travel from one spot to the other. For instance, if you see a photo of a galaxy that is 90 million light years away, you’re actually getting a glimpse of what that galaxy looked like 90 million years ago.
Planets are far closer to Earth than distant galaxies, so seeing a planet through a telescope or in a photo is not such a distant view into the past. In fact, it’s common to measure planet distances from the sun in light minutes or light hours as opposed to light years, since those numbers are smaller and easier to comprehend. For instance, Mercury is the closest planet to the sun. On average, it is about 36 million miles away. In light years, that number would be 0.000006123880620837039 light years away. It’s much easier to say that it is

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Retrieved Text: The closest planet to Sun is Mercury and the farthest is Neptune.
Pluto is a dwarf planet – relegated from its status as the ninth planet.
The eight planets of the solar system are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
The Sun is the primary source of energy for life on Earth. It is the closest star to the Earth, about 150 million kilometers from earth. The temperature of the Sun’s visible surface (photosphere) is about 6000 degree Celsius. However, the outer layer of Sun’s atmosphere, known as the Corona, is, on an average, about 2 million degree Celsius. The core of the sun is the center, and is about 15 million degree Celsius.
The Sun is made up of 73% hydrogen and 25% helium. It also has trace amounts of oxygen, carbon, iron and other elements. It is classified as a G-Type Main Sequence Star. It is about 4.6 billion years old and will continue to shine for another 5 billion years. After that it will grow into a Red Giant and then finally end its life as a white dwarf.
The planets are divided in the two groups – Inner planets and Outer planets.
Inner planets – Mercury, Venus, Earth, Mars. These are also known as terrestrial planets or rocky planets. These are denser and have a shorter periods of revolution.
Outer planets – Jupiter, Saturn, Uranus, Neptune. These are also known as Gas Giants or Gaseous planets. They are big in size and have a longer periods of revolution.
Jupiter is the biggest planet in the Solar System and

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Retrieved Text: A couple of numbers come to mind in astronomy that are part of the fields general knowledge. One such number is the Moon’s distance to the Earth. If you were to venture a guess of 384,00 km (238,600 miles), you’d be pretty close.
This number, however, is only the median distance of the Moon. Since Johannes Kepler (1571-1630), we have known that celestial bodies don’t move in a circle, but rather in an ellipse. With this logic, the Moon’s distance to the Earth varies. Especially impressive is when a full Moon occurs at its closest or furthest point to Earth. The images show the difference, as simulated by Stellarium planetarium software.
To the left, we can see the full Moon in the night from Friday to Saturday. The picture to the right shows the full Moon on the 14th of November, later this year. At this time, a full Moon will occur at its closest point to Earth. In raw numbers: currently, the moon is just over 407,000 km (253,000 miles) away, while in November that number would stand at 357,000 km (222,000 miles). Side note: the nearest point of an elliptical orbit is called the Perigee, and the furthest Apogee. Currently, the moon is nearing the Apogee.
For solar eclipse observation, the Moon’s distance, whether in Apogee or Perigee, plays an important role in the observation experience. If the Moon is close to the Earth, it won’t totally obscure the sun, resulting in a ring-shaped eclipse.
With the naked eye, the difference between the especially small or large full

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Retrieved Text: Mercury is the smallest, innermost, and least explored of the planets in the inner Solar System.
The little world remained completely mysterious until the 1970s, and to date only two missions have visited and observed Mercury up close: NASA's Mariner 10 probe, which launched in 1973, and NASA's MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) mission, which launched over three decades later in 2004.
BepiColombo, a joint endeavour between the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA), will bring this number to three when it launches in October 2018.
The surprising scarcity of spacecraft bound for Mercury is not because the planet is uninteresting, but because the innermost parts of the Solar System are a challenging region for exploration.
Mercury is incredibly close to the Sun–on average just under 60 million km compared to the Earth's nearly 150 million km–and as a result its environment is harsh and unfamiliar to our equipment. This is especially true when it comes to temperature.
In its hottest regions–at the equator during the day–Mercury's surface temperature can hit highs of over 400 degrees Celsius, while its coolest parts–the poles and at night–can dip to a bone-chilling -170 degrees Celsius. Any technology we send to the Sun-seeking planet must be able to endure long-term temperatures that are not only incredibly intense, but also highly changeable.
Additionally, Mercury's orbit is difficult for our probes to reach. Even when the Earth-Mercury distance is at a minimum, a great deal of energy is needed to brake any spacecraft into a suitable orbit such that it

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Retrieved Text: After a lot of controversies, our universe has 8 planets that revolve the sun and meet every criterion to be named a planet. The planets in order are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Venus is a very charming and mysterious planet. Often called the Aphrodite (Roman Goddess) planet as it symbolizes love and beauty, it is the closest planet to Earth. It is so named because it is the brightest planet in the sky and it has surface features named after female figures!
Venus is very similar to Earth in a lot of ways, and yet only Earth can support life. Scientists call this the Goldilocks Theory! Interesting name, right? Just as the porridge was just right in Goldilocks, everything on Earth is just right. Venus is too close to the sun due to which, the water can never flow as it gets evaporated instantly. Due to this, the planet is covered by a thick layer of clouds. Mars is too far away and so all the water on its surface had turned to ice. But Earth’s distance is just right which allows the surface water to flow from one end to the other. Earth has a medium sized atmosphere which helps in the flow of water and refreshment of atmosphere that supports life, whereas Venus is too close to the Sun to allow the proliferation of life. Venus is the closest planet to Earth. The picture of Venus with a white envelope is actually how it looks. The bright sun colored effect is

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Retrieved Text: Which of these planets is considered a dwarf planet ?
Which is the closest plant to the Sun ?
Jupiter is approximately how many times the mass of the earth ?
Which planet does not have observable rings ?
Which of these planets is considered a gas giant ?
Mars has how many confirmed moons/satellites ?
Which of the largest 8 planets is furthest from the Sun ?

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Retrieved Text: The planets are the central coterie of astrology. While the signs of the zodiac and the astrological houses set the stage for a horoscope, it is the planets that are the players upon that stage: it is their positions and the aspects (important angles) they make that form the bulk of any interpretation.
Classical astrology considered the apparent movements of seven known astrological planets, including the Sun and Moon, which are not planets in the astronomical sense. These seven were the celestial bodies that appeared to travel through the zodiac when viewed from earth: Sun, Moon, Mercury, Venus, Mars, Jupiter and Saturn. Once they were discovered, the three remaining planets - Uranus (found in 1781), Neptune (1846) and Pluto (1930) - were incorporated into astrological theory. The locations and aspects of other heavenly bodies, such as the asteroid Chiron (discovered in 1977), are also used by some astrologers in preparing a horoscope.
Each planet rules one or more signs, and in each case these are the signs in which the planet can most easily express its innate characteristics. A planet encounters most difficulty in manifesting its energies in the signs of its detriment, which are always the opposite signs to those of its rulership.
The planets are also said to be exalted in particular signs, and in the sign of its exaltation, a planet generates its power from the conditions provided by the characteristics of the sign. A planet is at its weakest and most ineffectual in the sign of its fall, where the nature of the sign actively

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Input Text: Read the passage below and choose the right answer to the following question (choices are larger orbit or smaller orbit? ):

The planets further from the Sun will have bigger orbits, and therefore take longer to revolve around the Sun.


Compared to Neptune, which is the furthest planet to the Sun, would Mercury, which is the closest planet from the Sun have a larger orbit or smaller orbit??

Target Text: smaller orbit?

#### Retrieved Documents ####

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Retrieved Text: The reason they are considered to be sister, or twin planets, is because they are almost identical in size, and because they both appear to be blue. Their chemical makeup is almost identical as well.
Where is the planet Uranus?
Uranus is the 7th planet from our Sun.\n. \nIt's orbit lies between the orbits of Saturn and Neptune..
Why was the planet uranus named uranus?
What planet is after Uranus?
How far away is Uranus from Neptune?
i want the anwser Comment: Unfortunately there isn't an exact answer. These planets orbit the Sun at different speeds and the distance between them is always changing.
Which is bigger Uranus or Neptune?
Uranus is a little bit bigger if you measure it with Neptune, buteven though Uranus is bigger- Neptune is actually heavier if youmeasure their weight. Which means even if Uranus is bigger, Neptune is heavier.
When were telescopes used to see and to photograph the planets Neptune Uranus and Pluto?
Uranus was discovered by Sir William Herschel in 1781. Neptune was discovered by John Couch Adams in 1846. Pluto was discovered by astronomer Clyde Tombaugh in 1930.
What is the distance between the planet Uranus and Neptune in miles?
Who discovered the planets Jupiter and Saturn and Uranus and Neptune and when?
Why is Uranus a planet?
What is the distance between the planets Uranus and Neptune?
The first planets discovered since ancient times were Uranus and Neptune How were they discovered?
Is the planet Neptune colder than Uranus?
Because Uranus's internal heat is lower than Neptune's -- possibly because it doesn't have a moon as large as Triton providing friction from gravitational

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Retrieved Text: Is Saturn closer to the Sun than Mercury?
Which Planet or Moon is Closest to the Sun?
Find out which Planet is closest to the Sun.
Which is closer to the Sun, Mercury or Mars?
Which is closer to the Sun, Mercury or Neptune?
Which is closer to the Sun, Mercury or Saturn?
Which is closer to the Sun, Mercury or Jupiter?
Which is closer to the Sun, Mercury or Earth?
Which is closer to the Sun, Mercury or Pluto?
Which is closer to the Sun, Mercury or Uranus?
Which is closer to the Sun, Mercury or Venus?
Is Mercury closer to the Sun than Earth?
Is Mercury closer to the Sun than Saturn?
Is Mercury closer to the Sun than Jupiter?
Is Mercury closer to the Sun than Uranus?
Is Mercury closer to the Sun than Neptune?
Is Mercury closer to the Sun than Venus?
Is Mercury closer to the Sun than Pluto?
Is Mercury closer to the Sun than Mars?

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Retrieved Text: Hudson is a 9-year-old writer inspired by fantasy, but Hudson also writes about non-fiction sometimes.
Hi, I am the universe. I am made up of many beautiful things. Stars are one of those things.
My stars glisten in the moonlight, giving my planets light at night. My biggest star is the Sun.
My Sun is made up of hot gas. It shines so brightly you would get blinded at your first sight of it.
Some of my stars make shapes and items, and others make shapes of gods. I have more than billions of stars in my universe. My stars are a very beautiful part of me.
Now I will tell you about my planets. Mercury is the closest to my famous star, the Sun.
Mercury is gray with white spots. Since Mercury is the closest to the Sun, it is in the warmest area of all of the planets that orbit the sun. Mercury is often hit by asteroids and is made up of hard solid rock.
Venus is made of gas and rock and is extremely hot. Venus is the second closest planet to the sun. Venus looks like an erupting volcano with lava all over it. Venus is very beautiful. On Venus you will see fire and gas, and it is hard to breathe there.
Earth is a very beautiful planet. Earth is, for all that humans know, the only life-giving planet in the world. Earth is the third closest planet to the sun. It is 75% water and 25% land. Earth has a lot of nature, such as trees flowers

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Retrieved Text: Eight planets orbit around the sun in our solar system, and the Earth is the third furthest from the sun. Illustration by Jarin Ashimine ('20).
Hello everyone and welcome to my third post!
So far, I have focused on how to easily find a few objects in the sky such as the moon and the Orion Nebula. In this post, you will learn more about our very own solar system and the planets within it.
The solar system is a gravitationally bound system made up of the sun and the objects that orbit it. Eight large planets along with their moons orbit the sun, along with smaller objects, such as dwarf planets, asteroids and comets. Our very own Earth is one of the eight main planets in the solar system and is the third planet from the sun. It is the only planet known to harbor life but we soon may find signs of living organisms on the red planet Mars, the fourth planet from the sun. Earth takes 365 days to go around the sun once (we call this a calendar year) while Mercury, the closest planet to the sun, takes just 88 Earth days. Neptune, the furthest from the sun, takes a whopping 165 Earth years.
Scientists estimate that the Solar System formed around 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. This means that a cloud of gas and dust in space was disturbed, maybe by the explosion of a nearby star, which is called a supernova. This explosion made waves

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Retrieved Text: The center of the Solar System is the Sun. The Solar System is made up of the Sun and all the planets, asteroids, and other objects that orbit the Sun.
There are eight planets in our Solar System. Starting with the closest to the sun they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. The closest four planets (Mercury, Venus, Earth, and Mars) are termed terrestrial planets, meaning they have a hard rocky surface. The furthest four planets (Jupiter, Saturn, Uranus, and Neptune) are called gas giants. These planets are much larger and their surface is composed of gas elements (mostly hydrogen).
view of the solar system and the planets.
In addition to the Sun and the eight planets, there are other objects that are part of the Solar System.
Dwarf planets - Dwarf planets are objects similar to planets in the Solar System, however they are defined as not large enough to have "cleared their orbital region of other objects." Some of the dwarf planets in the Solar System include Pluto, Ceres, Eris, Haumea, and Makemake.
Comets - Comets are objects made of ice, dust, and rocks that orbit the sun. They often have a visible "tail" of gas that comes from solar radiation and solar wind. Comets originate from the Kuiper belt and the Oort cloud.
Asteroid belt - The asteroid belt is a region between the planets Mars and Jupiter. In this region thousands of rocky objects orbit the Sun. They range in size from tiny dust like particles to the dwarf planet Ceres.
Kuiper belt - The

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Retrieved Text: Mercury - The planet with the second highest temperature in the Solar System and the closest planet to the Sun.
Earth - The only planet in the solar system that is known to have life. It has one natural satellite, the Moon.
Mars - Sometimes called the "red planet" and "the brother of Earth".
Jupiter - The largest planet in the Solar System.
Saturn - Sixth planet from the Sun. It has giant rings around it.
Uranus - Seventh planet from the Sun. It has 11 rings around it.
Neptune - The farthest planet from the Sun.

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Retrieved Text: Intrepid space travellers will be able to explore all the planets of our solar system as part of a fabulous new exhibition at the Eden Project this summer (July 27 to September 3).
The journey, known as the solar system safari, will start with a giant, moving projection of the Sun, complete with solar flares shooting from its surface.
Visitors then move to the desolate wasteland of Mercury, the planet closest to the Sun, before travelling to the searing, volcanic landscape of Venus, complete with a projection of its surface eruptions.
Explorers are then treated to a spectacular “fly-by” of Earth, getting a beautiful, immersive view of our planet as astronauts see it from space.
Next comes perhaps the most recognisable of planets in our solar system, Mars, which will be represented by a red, craggy landscape and a prototype of the ExoMars rover being developed by Airbus in the UK.
Visitors will then travel to the first of the gas giants and the biggest planet in our solar system, Jupiter. Because it would be impossible to walk on the surface of the planet, Eden explorers will view the beautiful planet from Europa, one of 69 moons that orbit Jupiter.
The other gas giant in our solar system, Saturn, is next on the journey and it will be rendered as a 3D hologram, viewed from an icy cave on its moon Enceladus.
The milky-blue icy landscape of Uranus, the coldest planet in our solar system is next, followed by its fellow ice giant Neptune, the furthest planet from the Sun, which will be

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Retrieved Text: Last week, there was a lot of talk in the United States about the chilly weather affecting many parts of the country. Fortunately, here in New Jersey, this cold spell seems to have come to an end.
But while we're lucky enough to have a change in weather, not every other body in the solar system can be so lucky.
Earth is the only planet with a habitable climate system thanks to our location relative to the Sun, and Earth being geologically active. Our oceans, atmosphere, and molten core all help to regulate our climate to a suitable environment for life as we know it.
Mercury is the closest planet to the Sun, but its temperature changes drastically from day to night. During the day, Mercury is around 800 degrees. Then, as the planet rotates, the nighttime surface falls to almost -300 degrees!
This drastic change in temperature is all due to the fact that Mercury has hardly any atmosphere. As a result, the Sun's heat isn't held on the surface at night.
Even though Venus isn't the closest planet to the Sun, it is the hottest! Thanks to the thick atmosphere of mainly carbon dioxide, heat from the Sun gets trapped on the surface of Venus, making the planet about 900 degrees Fahrenheit. There are also many volcanoes on the surface that may still be active, adding to the gases in the atmosphere.
Mars has a much thinner atmosphere than Earth, so it’s hard to keep the Sun’s heat on the surface. On average, Mars is about -80 degrees Fahrenheit. But,

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Retrieved Text: Eight planets circle the Sun. These planets are the only ones in the universe that are currently visible from Earth with enough detail to study their seasons. Several forces govern the seasons of our solar system's planets. If a planet is tilted on its axis, it is more likely to have a distinct seasonal cycle. Also, if a planet has a variable distance from the sun, it is more likely to experience distinct seasons. Though every planet in our solar system experiences some seasonal changes, several planets experience only negligible changes.
Mercury is a planet of extreme motion. First, it has a strange rotation cycle. It rotates three times in two of its years. Mercury's orbit is also eccentric. It follows a highly elliptical path around the sun. This makes the Sun's journey through Mercury's sky very different than its journey through Earth's sky. From Mercury, the sun to appears to go backward sometimes. Last, Mercury's axis is almost perpendicular to the plane of its orbit around the Sun. All this erratic movement makes it impossible to tell the start or finish to any season on Mercury.
Venus's axis is only slightly tilted. Earth's axis is tilted 23.5 degrees, but Venus is only titled 3 degrees. This lack of tilt means the planet's surfaces receive a uniform amount of the Sun's energy. Though Venus has seasons, there is little change from one to the next. Venus also has a much shorter orbit than Earth, making its seasons very brief. Last, Venus is covered with a thick blanket of

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Retrieved Text: It’s easy to forget that we live on one tiny planet in a huge universe, and even when we begin to talk about it with children it’s a very difficult topic to comprehend. But learning about the solar system at a young age can really inspire astronomy as a passion, ignite imaginations and encourage a long-term fascination that may never leave them.
The natural inquisitiveness that children possess will spark some fantastic discovery into our universe. Look up at the stars, and the moon, and see what questions they come up with.
We’ve come up with some great facts to kick-off an introduction to the solar system. Plus to fuel their imagination even further, we’ve dreamed up a couple of great activities for kids to create their own planets (once they know a bit more about the real ones) and then get creative by inventing their own aliens.
In the Solar System alone there are seven other planets (RIP, Pluto), many dwarf planets, satellites and moons, and of course, the Sun.
Our solar system is in a galaxy called the Milky Way. In the Milky Way is it estimated that there are approximately 30 billion solar systems. We think that there are 100 billion galaxies in the universe. This means that the universe is much bigger than we can even imagine!
There are eight planets in the Solar System that all orbit the sun. Each of the planets are different: some have moons, some have rings, some are made of rock, and some are made of gas. Read on for fascinating

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Retrieved Text: With eight other planets, dozens of moons, thousands of minor planets, myriads of comets and meteoroids and in addition interplanetary dust which circle around a central star named the Sun, Venus is a member of a collection of celestial objects which is called the Solar System. It extends over 12,000 million kilometres in space. Counting from the Sun, Venus is the second planet. Venus' orbit is the most circular of any planet, with an eccentricity of less than 1%. The dominant body is the Sun which accounts for more than 99% of the mass of the Solar System. Our Solar System was once regarded as the largest and central part of the Universe. But today we know it is just a tiny speck compared with the rest of the Universe.
Venus belongs to the group of planets from Mercury to Saturn that are bright and easily seen by the naked eye, and well known to the ancients. The three most distant planets - Uranus, Neptune, and Pluto - were discovered after the invention of the telescope in 1609. Uranus and Neptune can be seen with a pair of binoculars, but to detect Pluto requires a moderately-sized telescope.
Compared to the Sun, Venus and the other planets are relatively cold and only visible by reflected sunlight. To observers on Earth, both Venus and Mercury show phases like the Moon, because their orbits lie inside the Earth's orbit. So Venus and Mercury are called inferior planets. On the other hand, Mars, Jupiter, Saturn, Uranus and Neptune lie outside, so they

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Retrieved Text: Sciency Thoughts: Neptune reaches Solar Conjunction.
The planet Neptune will reach Solar Conjunction (i.e. be directly on the other side of the Sun from the Earth) at 1.56 pm GMT on Sunday 4 March 2018. This means that it will both be at its furthest from the Earth this year, about 30.94 AU (30.94 times the average distance between the Earth and the Sun, or about 4 629 000 000 km), and while not completely obscured by the Sun, due to differences in the tilts of the orbits of Earth and Neptune, it will be close enough to the Sun to be invisible for several weeks.
The relative positions of Neptune and Earth at Solar Conjunction (not to scale). Bob's Spaces.
Neptune orbits the Sun at an average distance of 30.11 AU, completing one orbit around the Sun every 165 years. This means that the planet is almost stationary compared to the faster moving Earth, so that it reaches Solar Conjunction only four days later each year than the year before, and reaches opposition (when it is directly opposite the Sun seen from the Earth), roughly six months later.

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Retrieved Text: Since 2006, due to a controversial decision by the International Astronomical Union (IAU) that demoted Pluto to a dwarf planet, we have had eight planets.
Mercury is a small planet, which can reach extreme temperatures. Since the planet is the closest one to the Sun, it can reach temperatures of 450°C. However, because the planet has almost no atmosphere due to very little gravity, the surface also drops to low temperatures of -170°C.
Venus is farther from the Sun than Mercury is, but it stays hotter due to its thick, toxic atmosphere. The main compound in Venus’ atmosphere is carbon dioxide, which creates the strongest greenhouse effect of any planet.
Undoubtedly, you already know a lot about Earth, but you may not know that our planet is the only one in our Solar System that has plate tectonics. The Earth’s outer crust is broken up into various sections called plates, which can move. These plates also take carbon out of the atmosphere and recycle it. This prevents a greenhouse effect like Venus’ and keeps the Earth from getting too hot. This is just one feature of our unique planet that helps support life.
Mars is the only inner planet, except for Earth, that has moons. Its two moons are called Phobos and Deimos. In Greek mythology, Phobos is a son of Ares (the equivalent of Mars) and Deimos is a figure that represents dread.
Jupiter is the model for gas giants as well as being the largest planet in our Solar System. It was named after the Roman king of the

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Retrieved Text: The solar system consists of 8 planets. These Eight Planets rotate around Sun continuously. Names of Eight Planets Names given in the table.
➥Earth is the third planet from the sun.
➥Mercury is the first planet from Sun.
➥Inner planets: Mercury, Venus, and Earth are called inner planets in the solar system.
➥Outer planets: Mars, Jupiter, Saturn, Uranus, and Neptune are called outer planets.
➥The last planet from the sun in the solar system is Neptune.
➥Jupiter is the largest planet and mercury is the smallest planet in the Solar System.

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Retrieved Text: We have nine planets in our Solar System. These planets circle around the sun (as I’m sure you know already) this is called orbits.
A lot of astronomy people like to think of the Solar System been made up in two parts We have the Inner Solar System which has Mercury, Venus, Earth and not forgetting Mars. These are closest to the sun and are called the terrestrial planets simply because the have very solid rocky surfaces.
The Outer Solar System has Jupiter, Saturn, Uranus, Neptune these are sometimes called the gas giants Out past Neptune you’ll find the small planet of Pluto which has a solid but icier surface. Many don’t class this as a planet anymore but you can read this on the Pluto page. These two systems are separated by the asteroid belt Our Solar System also contains comets, moons, dust, gas and some minor planets.
The solar system is made of the eight planets that orbit our sun it is also made of asteroids, moons, comets and lots, lots more. The sun has such powerful gravity it tries to pull the planets towards it. While the planets try to fly away in the end they are kind of in the middle floating around the sun. They are 140 moons that orbit the eight planets in the solar system. The moons don’t orbit the sun they orbit the planet they are nearest to.

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Retrieved Text: In Classical antiquity, the classical planets or naked eye planets were the seven non-fixed objects visible in the sky: the Sun, the Moon, and the planets Mercury, Venus, Mars, Jupiter, and Saturn. Ancient astronomers observed how certain lights moved across the sky relative to the fixed stars. They called these objects asteres planetai, which means wandering stars.
The SEVVEN Wanderers range of merchandise includes the classical planet symbols, placing the planets in order, closest to Earth to furthest, as the Moon, Mercury, Venus, Sun, Mars, Jupiter, and Saturn, as they did with the the Ptolemaic system.

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Retrieved Text: While we have been learning about the nine planets in our solar system since childhood, of late there has been a bit of confusion about the number of planets with Pluto being knocked off the list.
Solar system is a minute component of the vast universe which was formed billions of years ago. It consists of the Sun and several celestial bodies revolving around it. These include planets (and their satellites), asteroids, meteoroids, etc. Until 2006 the number of planets in our solar system was nine, but the exclusion of Pluto has left us with only eight planets.
The Sun is the center of our solar system and has eight planets orbiting it. These include―starting from the nearest to the Sun―Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Initially considered a planet, Pluto was officially declared a dwarf planet by the International Astronomical Union (IAU) in 2006, thus bringing the number of planets down to eight. Let's have a brief look at each of these planets.
Mercury: Mercury is the smallest planet in our solar system. At 3031.670 miles, its diameter is 38 percent the diameter of the Earth. It has extreme climate with temperature ranging between −180 to 430 °C. It is located at a distance of 0.39 AU. On the basis of information sent by Mariner 10 spacecraft, scientists suspect that some volcanic activity is occurring on Mercury.
Venus: Venus is a small, rocky planet, typically characterized by a thick blanket of yellowish clouds of sulfuric acid. With a diameter of 7521.076 miles, Venus is bigger than

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Retrieved Text: nRelax Take a deep breathe hold it count to three exhale slowly relax Dream The solar system The planets orbiting the sun the first planet and the closest planet to the sun making it journey orbiting around the sun is Mercury , it’s orbit around the sun is 35 million miles, next is Venus 108,267 million miles, it orbit around the sun, Earth 93 million miles, Mars 141,600,000 miles, it’s orbit around the sun, Jupiter, 484,000,000 miles, Saturn 886,000,000.7 million miles, Chiron, a new planet discovered in our solar system, 886,000,000 miles, Uranus, 1,000,700,083 million miles, it’s orbit around the Sun, Neptune, 4000, 400,002 million kilometers, 2000,294,000 million miles, it’s orbit around the Sun, Pluto, 3600 million miles it’s orbit around the Sun. These are the orbits of the planets in our Solar System as we know them today. The stars, the concellations Aries. The Ram, Mars, Tauras, the Bull, Venus, Gemini, the Heavenly Twins, Mars, Cancer, The Crab, the Moon, Leo, the Lion, the Sun, Virgo, the sign of the Virgin the planet Mercury, Libra, the sign of the Scales, planet Venus, Scorpio, the sign of the Scorpion Man, the ruling planet is Pluto, Sagittarius, the sign of Centaur or Archer, the ruling planet is Jupiter, Capricorn, the sign of the Goat, the ruling planet is Saturn, Aquarius, the sign of the Water Bearer, the Ruling planet is Uranus, Pices , the sign of two fish swimming in opposite directions the ruling planet is Neptune. Relax , take a deep breath, exhale slowly, ralx…dream, the

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Retrieved Text: An object that has a perfectly circular orbit never varies in distance from the object it's orbiting around. With the possible exception of a few spacecraft, none of the objects known to be orbiting the sun has such an orbit. Rather, the planets orbit in ellipses, however slight. So there is a point in each orbit when the planet is closest to the sun. That point is called the perihelion. Likewise, there is a point when each planet is farthest from the sun. That point is the aphelion.
Of course, the longer the orbit the longer the time between these points in the planet's orbit. Mercury goes through perihelion every 88 days. Neptune takes 165 years!
There's a separate page listing aphelion times, but here's a list of perihelion times in Universal Time for the 2010 decade. The distances from the sun in astronomical units, kilometers, and miles are listed. An astronomical unit is the average distance between Earth and the sun.
Saturn, Uranus, and Neptune don't go through perihelion during this decade.

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Retrieved Text: Our solar neighborhood is really an exciting place. It is full of different heavenly bodies such as planets, moons, asteroids, meteors, comets, and many other exciting objects. Let us learn more about them.
Planets are large natural objects that orbit, or revolve around, stars. You are standing on one at this moment! Yes, Earth is a planet too. Today, we have eight planets orbit the star called the Sun. In order, from the closest to the Sun, these planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
While some of the planets are small, rocky bodies with a solid ground – Mercury, Venus, Earth and Mars; the others are big gas giants – Jupiter, Saturn, Uranus, and Neptune.
Unfortunately, Pluto failed to meet the third condition and had to step down from being a planet to a “dwarf planet”.
So far, hundreds of worlds beyond our solar system have been discovered and many new ones are in the process of being discovered. Scientists believe some of these planets may sustain alien life. Well, no one knows for sure, but there is a high probability that an alien kid elsewhere in the galaxy is also reading about us and the Earth in an article like this!
Stars are giant spheres of superhot gas, generally made up of hydrogen and helium. Stars get so hot and bright because of a process called nuclear fusion that takes place inside them. Nuclear fusion is a process in which hydrogen gas gets converted into helium, releasing light and heat. Though it seems to us

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Retrieved Text: The 6th of January 2018 marks the transit of planet Mercury (Budha) from Rashi (horoscope, sun-sign) Scorpio (Vrischika) to Sagittarius (Dhanu). But what does the transit of planet Mercury from Scorpio to Sagittarius mean-signify?
Mercury will remain in Dhanu (Sagittarius) from the 6th of January to the 28th of January 2018, i.e., for ~24 days. On the 28th it will move on to the next Rashi – Makar (Capricorn).
What is planet Mercury? Mercury is the 1st and the closest planet to the Sun in our solar system. In size, it is the smallest planet. It takes the least time to orbit around the sun, i.e., 88 Earth days. Its diameter is ~4,880 kms. Roughly 2.6 Mercury sizes make/equal the size of one Earth.
Mercury being the closest to the Sun, it is almost ~58 million kms from the Sun; whereas the Earth is ~149 million kms. Therefore, Earth is at least 2.5 times further away from the Sun as compared to Mercury.
There have been two prominent missions to the Mercury. These are the Mariner 10 and MESSENGER.
What are Mercury’s humanistic characteristics? Mercury called ‘Budha’ in Sanskrit/Hindi, is regarded as one of the most influential celestial bodies in relation to humans on Earth; after the Sun, the Earth’s moon. In fact, Wednesday in Sanskrit/Hindi is called ‘Budhavar’ as per the Hindu calendar, in dedication to the planet. The ‘Budha’ part of ‘Budhavar’ means the planet Mercury (as indicated in the 1st Para).
Among the earliest traces of the Mercury, it can be dated back to the Vedic texts-literature, which is

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Retrieved Text: 20 major planets and moons to know about from our Solar System, in a small fun online game.
"Solar Puzzle" is a free online knowledge level game about the Solar System.
It is part of the Interactive Astronomy Observatory, to explore and study the 9 main planets of our solar system, plus latest discoveries about new planets, like Sedna and other coming soon from the Oort cloud(according to latest discoveries), and some notable satellites or moons. This fun educational application is a short flash game, which will run on medium class desktop computers, laptops and tablets, and reward the player with a new knowledge level, right in the web browser.
The Astronomy Knowledge Board include 20 pieces of movable planet pictures to play with.
Interactive Astronomy Observatory educational tools.
Which is the biggest planet in the Solar system?
What is the most exciting discovery about Europa?
Which planet does Europa moon orbits?
Where is Mercury planet situated?
Where is Jupiter planet situated?
How many moons are there it the Solar System?
Which is the smallest moon in the Solar system?
Is there an asteroid ring in the Solar System?
Which is the biggest object in the asteroid belt?
Why Venus have no atmosphere?
Which is the biggest gas giant in Sol?
How to play Solar Puzzle.
Drag and drop the planet pictures, located top of the screen, to the outlines of the planet, in the middle.
There were 5 Cosmic Supplies, that would be subtracted on wrong drop.
will return on place, until all placed correctly.
Know the planets in the Solar System, their positions, some of their satellites and interesting facts about them.
Io, Europa, Saturn,

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Retrieved Text: The Solar System planet order is easy to remember with this classic phrase: "My very educated mother just sent us nine pickles" — My (Mercury), Very (Venus), Educated (Earth), Mother (Mars), Just (Jupiter), Sent (Saturn), Us (Uranus), Nine (Neptune), Pickles (Pluto)!
The Solar System is the "system" of planets, asteroids, and comets that orbit around our Sun. Our Solar System is in the Milky Way galaxy — that bright band of stars you can see going across the sky at night. There are about 200,000,000,000 (200 American billion) stars in the Milky Way galaxy. Our Sun is just one. The Milky Way is a spiral galaxy. Newer suns (such as our Sun) are in the spiral arms. Older suns are in the center of the galaxy. Our Solar System is in the Orion Arm of the Milky Way.
(Image NASA et al.) Our Solar System revolves around the center of the Milky Way Galaxy (the Galactic Center). A large Black Hole lies at this center. An unusual concentration of stellar matter surrounds this Black Hole. This was discovered in February 1974 by Bruce Balick and Robert Brown, and named Sagittarius A* (pronounced "Sagittarius A star").
Sagittarius A* was determined to be the center of the Milky Way, about 26,000 light years from our Solar System. We know the center is a Black Hole from observations of nearby suns in very fast orbits around it, showing high gravitational attraction. In 1999, knowing that Sagittarius A* was the center of the Milky Way Galaxy allowed astronomer Mark Reid and associates at

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Retrieved Text: It can be difficult to grasp just how enormous the solar system is. At the heart of that system is the sun, the star around which all the planets orbit. Even though those planets seem impossibly far away, scientists are able to calculate where they will be in their rotations at any given moment, and how many light years they are traveling away from Earth.
This makes it easier to understand just how far away the planets, stars, asteroids and comets are from Earth or from the sun. Instead of having to comprehend what it means when a planet is trillions and trillions of miles away, thinking in light years can help you visualize how long it takes for light to travel from one spot to the other. For instance, if you see a photo of a galaxy that is 90 million light years away, you’re actually getting a glimpse of what that galaxy looked like 90 million years ago.
Planets are far closer to Earth than distant galaxies, so seeing a planet through a telescope or in a photo is not such a distant view into the past. In fact, it’s common to measure planet distances from the sun in light minutes or light hours as opposed to light years, since those numbers are smaller and easier to comprehend. For instance, Mercury is the closest planet to the sun. On average, it is about 36 million miles away. In light years, that number would be 0.000006123880620837039 light years away. It’s much easier to say that it is

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Retrieved Text: The closest planet to Sun is Mercury and the farthest is Neptune.
Pluto is a dwarf planet – relegated from its status as the ninth planet.
The eight planets of the solar system are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
The Sun is the primary source of energy for life on Earth. It is the closest star to the Earth, about 150 million kilometers from earth. The temperature of the Sun’s visible surface (photosphere) is about 6000 degree Celsius. However, the outer layer of Sun’s atmosphere, known as the Corona, is, on an average, about 2 million degree Celsius. The core of the sun is the center, and is about 15 million degree Celsius.
The Sun is made up of 73% hydrogen and 25% helium. It also has trace amounts of oxygen, carbon, iron and other elements. It is classified as a G-Type Main Sequence Star. It is about 4.6 billion years old and will continue to shine for another 5 billion years. After that it will grow into a Red Giant and then finally end its life as a white dwarf.
The planets are divided in the two groups – Inner planets and Outer planets.
Inner planets – Mercury, Venus, Earth, Mars. These are also known as terrestrial planets or rocky planets. These are denser and have a shorter periods of revolution.
Outer planets – Jupiter, Saturn, Uranus, Neptune. These are also known as Gas Giants or Gaseous planets. They are big in size and have a longer periods of revolution.
Jupiter is the biggest planet in the Solar System and

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Retrieved Text: A couple of numbers come to mind in astronomy that are part of the fields general knowledge. One such number is the Moon’s distance to the Earth. If you were to venture a guess of 384,00 km (238,600 miles), you’d be pretty close.
This number, however, is only the median distance of the Moon. Since Johannes Kepler (1571-1630), we have known that celestial bodies don’t move in a circle, but rather in an ellipse. With this logic, the Moon’s distance to the Earth varies. Especially impressive is when a full Moon occurs at its closest or furthest point to Earth. The images show the difference, as simulated by Stellarium planetarium software.
To the left, we can see the full Moon in the night from Friday to Saturday. The picture to the right shows the full Moon on the 14th of November, later this year. At this time, a full Moon will occur at its closest point to Earth. In raw numbers: currently, the moon is just over 407,000 km (253,000 miles) away, while in November that number would stand at 357,000 km (222,000 miles). Side note: the nearest point of an elliptical orbit is called the Perigee, and the furthest Apogee. Currently, the moon is nearing the Apogee.
For solar eclipse observation, the Moon’s distance, whether in Apogee or Perigee, plays an important role in the observation experience. If the Moon is close to the Earth, it won’t totally obscure the sun, resulting in a ring-shaped eclipse.
With the naked eye, the difference between the especially small or large full

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Retrieved Text: Mercury is the smallest, innermost, and least explored of the planets in the inner Solar System.
The little world remained completely mysterious until the 1970s, and to date only two missions have visited and observed Mercury up close: NASA's Mariner 10 probe, which launched in 1973, and NASA's MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) mission, which launched over three decades later in 2004.
BepiColombo, a joint endeavour between the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA), will bring this number to three when it launches in October 2018.
The surprising scarcity of spacecraft bound for Mercury is not because the planet is uninteresting, but because the innermost parts of the Solar System are a challenging region for exploration.
Mercury is incredibly close to the Sun–on average just under 60 million km compared to the Earth's nearly 150 million km–and as a result its environment is harsh and unfamiliar to our equipment. This is especially true when it comes to temperature.
In its hottest regions–at the equator during the day–Mercury's surface temperature can hit highs of over 400 degrees Celsius, while its coolest parts–the poles and at night–can dip to a bone-chilling -170 degrees Celsius. Any technology we send to the Sun-seeking planet must be able to endure long-term temperatures that are not only incredibly intense, but also highly changeable.
Additionally, Mercury's orbit is difficult for our probes to reach. Even when the Earth-Mercury distance is at a minimum, a great deal of energy is needed to brake any spacecraft into a suitable orbit such that it

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Retrieved Text: After a lot of controversies, our universe has 8 planets that revolve the sun and meet every criterion to be named a planet. The planets in order are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Venus is a very charming and mysterious planet. Often called the Aphrodite (Roman Goddess) planet as it symbolizes love and beauty, it is the closest planet to Earth. It is so named because it is the brightest planet in the sky and it has surface features named after female figures!
Venus is very similar to Earth in a lot of ways, and yet only Earth can support life. Scientists call this the Goldilocks Theory! Interesting name, right? Just as the porridge was just right in Goldilocks, everything on Earth is just right. Venus is too close to the sun due to which, the water can never flow as it gets evaporated instantly. Due to this, the planet is covered by a thick layer of clouds. Mars is too far away and so all the water on its surface had turned to ice. But Earth’s distance is just right which allows the surface water to flow from one end to the other. Earth has a medium sized atmosphere which helps in the flow of water and refreshment of atmosphere that supports life, whereas Venus is too close to the Sun to allow the proliferation of life. Venus is the closest planet to Earth. The picture of Venus with a white envelope is actually how it looks. The bright sun colored effect is

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Retrieved Text: Which of these planets is considered a dwarf planet ?
Which is the closest plant to the Sun ?
Jupiter is approximately how many times the mass of the earth ?
Which planet does not have observable rings ?
Which of these planets is considered a gas giant ?
Mars has how many confirmed moons/satellites ?
Which of the largest 8 planets is furthest from the Sun ?

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Retrieved Text: The planets are the central coterie of astrology. While the signs of the zodiac and the astrological houses set the stage for a horoscope, it is the planets that are the players upon that stage: it is their positions and the aspects (important angles) they make that form the bulk of any interpretation.
Classical astrology considered the apparent movements of seven known astrological planets, including the Sun and Moon, which are not planets in the astronomical sense. These seven were the celestial bodies that appeared to travel through the zodiac when viewed from earth: Sun, Moon, Mercury, Venus, Mars, Jupiter and Saturn. Once they were discovered, the three remaining planets - Uranus (found in 1781), Neptune (1846) and Pluto (1930) - were incorporated into astrological theory. The locations and aspects of other heavenly bodies, such as the asteroid Chiron (discovered in 1977), are also used by some astrologers in preparing a horoscope.
Each planet rules one or more signs, and in each case these are the signs in which the planet can most easily express its innate characteristics. A planet encounters most difficulty in manifesting its energies in the signs of its detriment, which are always the opposite signs to those of its rulership.
The planets are also said to be exalted in particular signs, and in the sign of its exaltation, a planet generates its power from the conditions provided by the characteristics of the sign. A planet is at its weakest and most ineffectual in the sign of its fall, where the nature of the sign actively

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Input Text: Read the passage below and choose the right answer to the following question (choices are bigger or smaller ):

In bigger atoms, valence electrons are farther from the nucleus.


If valence electrons are far from an atom's nucleus, the atom is likely bigger or smaller?

Target Text: bigger

#### Retrieved Documents ####

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Retrieved Text: As seen in the previous section on the octet rule, atoms tend to lose or gain electrons in order to attain a full valence shell and the stability a full valence shell imparts. Because electrons are negatively charged, an atom becomes positively or negatively charged as it loses or gains an electron, respectively. Any atom or group of atoms with a net charge (whether positive or negative) is called an ion. A positively charged ion is a cation while a negatively charged ion is an anion. In this section, we briefly look at some of the processes through which electrons are gained and lost in the formation of ions.
The process of gaining or losing an electron requires energy. There are two common ways to measure this energy change: ionization energy and electron affinity.
The ionization energy is the energy it takes to fully remove an electron from the atom. Ionization energy is a property that varies predictably across the periodic table. Group I and II elements with few electrons in their outer shell have very low ionization energies, while ionization energies increase dramatically moving right along the periodic table. The octet rule gives a straightforward (albeit simplified) explanation of this trend: elements with few valence electrons (those on the left of the periodic table) readily give them up in order to attain a full octet within their inner shells.
When several electrons are removed from an atom, the energy that it takes to remove the first electron is called the first ionization energy, the energy it takes to

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Retrieved Text: 3. Type of waves that pass through soft body tissues but stopped by bones.
5. Type of waves that cause sunburn.
6. Part of the spectrum our eyes are sensitive to.
8. The space around the nucleus of an atom where electrons are found.
9. Neutral particle found in the nucleus of an atom.
12. Number of protons in an atom's nucleus.
13. Forms of the same element with different numbers of neutrons.
14. The sum of protons and neutrons in an atom.
15. Last name of chemisty who gave us the law of definite proportions.
16. Greek philosopher who first coined the idea of the atom.
20. A way of illustrating valence electrons.
22. Last name of scientists who discovered electrons.
23. A testable prediction to explain an observation.
24. Last name of chemisty who gave us the law of conservation of matter.
25. Type of electrons in the outermost energy level of an atom.
26. Waves with the lowest frequencies of the spectrum.
1. Regions of space in which electrons can move about the nucleus.
2. The four basic elements of matter according to the ancient Greeks [no spaces between words].
4. A fact of nature that is observed so often it is accepted as truth.
7. Type of waves that travel at the speed of light through space.
10. Small, dense, positively charged central core of an atom.
11. Positively charged subatomic particle.
17. Last name of scientist who discovered the nucleus.
18. An explanation based on many tests.
19. Type of waves with highest frequency and shortest wavelength.
21. Type of wave energy given off by the human body and other warm objects.

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Retrieved Text: – An element is defined as a substance which cannot be decomposed into other substances. The smallest particle of an element which takes part in chemical reaction is known as atom.
– All matter is composed of atoms which are infinitesimally small.
from the stand point of electrical conductivity, as conductors, semiconductors or Insulators .To be conductor, the substance must contain some mobile electrons that can move freely between atoms. These free electrons come only from the valence (outer) orbit of the atom Conductivity depends on the number of electrons in the valence orbit.
“The energy level of an electron increases as its distance from the nucleus increases. Thus an electron in the second orbit possesses more energy than electron in the first orbit, electrons in the third orbit have higher energy than in the second orbit and so on. It follows, therefore, that electrons in the last orbit will possess very high energy. These high energy electrons are less bound to the nucleus and hence they are more mobile. It is the mobility of last orbit electrons that they acquire the property of combining with other atoms. Further due to this combining power of last orbit electrons of an atom they are called valence electrons”.
Atoms with fewer than four valence electrons are good conductors.
Atoms with more than four valence electrons are poor conductors.
Atoms with four valence electrons are semiconductors.
Normally, the atoms are electrically neutral, that is, the number of electrons and protons are the same, cancelling each other’s electrical force. Atoms “stay together’ because unlike charges attract each

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Retrieved Text: Electron dot structures, also called Lewis structures, are a graphical representation of the way electrons are distributed throughout a compound. Each element's chemical symbol is surrounded by lines, representing bonds, and dots, representing non-bonded electrons. When drawing an electron structure, your goal is to make each element's valence, or outer electron shell, as full as possible, without going over the maximum number of electrons for that shell.
Determine each element in the structure by looking at its chemical formula. For example, carbon dioxide's formula is CO2. Therefore it has one carbon atom and two oxygen atoms.
Look up each element on the Periodic Table. Note each group, or column number. This reflects how many valence electrons the element has. For instance, carbon is in group 4A and oxygen is in group 6A; therefore carbon has four valence electrons and oxygen has six.
Add the valence electrons of all the elements. This is the total number of electrons available for the dot structure. Since 4 + 6 + 6 = 16, there will be 16 electrons in carbon dioxide's Lewis structure.
Determine which element is the least electronegative, or has the weakest pull on the electrons, by looking on an electronegativity chart or by examining the element's position relative to the other elements on the Periodic Table. Elements generally increase in electronegativity from left to right and from bottom to top. Carbon is the least electronegative element in the compound, with a value of 2.5.
Place the least electronegative element in the center of the structure, then surround it with the other

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Retrieved Text: You will place electrons in the appropriate energy levels outside of an atom.
Explain that an atoms outermost electrons are responsible for an elements reactivity.
Identify the electron arrangement within atomic energy levels.
Explain that an electrons energy is related to its distance from the nucleus.
An atom has three subatomic particles: the proton, the neutron, and the electron. The proton has a positive charge, is located in the nucleus and is responsible for an atom's identity. The number of protons does not change in an element, and is equal to the atomic number on the periodic table. Neutrons are also located in the nucleus, but have no charge.
The electrons are located outside the nucleus, and have a negative charge. The electrons will arrange themselves into specific energy levels, starting with the level closest to the nucleus. Each energy level has a maximum number of electrons it can hold: two in the first, eight in the second, 18 in the third and 32 in the fourth. As the distance of the energy level from the nucleus increases, so does the energy the electrons contain.
The arrangement of the electrons in their energy levels is called the "electron configuration." In a neutral atom, the number of electrons will be the same as the atomic number, or number of protons. For learners to place the electrons in the appropriate energy level, they should identify the atomic number, and start placing the electrons in energy levels, the closest to the nucleus first. Once the energy level has its maximum number of electrons, they should

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Retrieved Text: An atom is one of the most basic units of matter in the known universe. Of course, you'll learn that far smaller components exist as you move forward through the physical sciences, but for the purposes of basic chemistry and physics, the atom--along with the protons and neutrons that make up its nucleus, and the electrons that orbit it like planets around the sun--is as basic as you'll need to get. If you want to make a model of a neon atom, you should keep in mind that it has 10 electrons.
Spray paint your foam balls to differentiate what they represent. Separate them into three groups: the large foam ball, two of the small ones, and the remaining eight. Lay each group on a different piece of newspaper (to protect the surface) and spray each group a different color, making sure your room is well ventilated. The large ball represents the atom's central nucleus, while the first two small balls represent its inner two electrons. The other eight balls represent its outer, or valance, electrons. Allow the balls at least two hours to dry before handling them.
Label the nucleus (large foam ball) using a black, permanent marker. Write neon's symbol "Ne" on it, as well as "P: 10" and "N: 10" to indicate the respective numbers of protons and neutrons.
Snip a piece of craft wire long enough to form a ring outside the nucleus and thread it through the two designated inner electrons (small foam balls). Attach each of the electrons to the nucleus using a

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Retrieved Text: As a homeschooling mom, I think hands on activities make learning science so much more interesting and fun. I also think they help children to understand science in a more concrete way. Things like atoms and molecules are pretty hard for a young child to comprehend without something tangible to relate to. In this post, and in a series of posts that will follow, I want to share with you some ideas for teaching elementary and middle school aged children about chemistry.
Let’s start with atoms and molecules.
Atoms are tiny tiny particles that make up all matter. You can’t see them - in fact, they are so tiny that millions and millions of them can fit in the point of the very sharpest pencil. But eveything around us is made of millions and millions of atoms - our bodies, our homes, our pets, the trees, even the air we breathe! To help make this concept more concrete, take a look through a magnifying glass at an image in a book or a picture printed from your computer. This will work best with a magnifying glass that magnifies at 4X or higher.
What do you see? Can you see that the picture is made from many many tiny dots? When you look at the picture with just your eyes, you don’t see the dots, but the picture is really just a whole lot of tiny dots of color put together. Atoms are like this - only even smaller!
This is a fun activity for a group of children. You build

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Retrieved Text: the smallest unit of an element that has all of the properties of the element; basic building block of matter.
the number of protons and neutrons in the nucleus of one atom of the element.
the number of protons contained in each nucleus of its atoms of the element.
a horizontal row (left to right) in the periodic table.
a vertical column (up and down) on the periodic table.
a chart that organizes information about all of the known elements according to their atomic number.
describes how likely an element is to form bonds with other elements.
group 1 metals on the periodic table that contain 1 valence electron and lose their valence electrons the most easily, making them the most reactive metals.
group 1 metals on the periodic table that contain 2 valence electrons and are the second most reactive metals.
group 3-­12 on the periodic table. They have varying valence electrons and do not follow the normal trends of the other metals. They form brightly colored compounds and ions in solution.
group 17 nonmetals on the periodic table that contain 7 valence electrons. They only need to gain 1 valence electron to have a stable octet. They gain valence electrons the most readily, making them the most reactive nonmetals.
group 18 elements on the periodic table that contain 8 valence electrons (He has 2) and a full valence shell making them very stable and inert.
an element that has some properties of a metal and some properties of a nonmetal. The metalloids are found on the boron staircase, there are 7 metalloids: B, Si, Ge, As,

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Retrieved Text: The History of the Atom Timeline: 400 BC Scientist: Democritus (Greek Philosopher) Democritus was a Greek philosopher who was Each atom (of an element) is different in structure from other atoms (of other elements) An atom can be divided in smaller subatomic particles: Protons, Electrons and Neutrons The nucleus is the centre of an atom. It contains protons and neutrons. Electrons orbit... History of the Atom – Worksheet/Review sheet Name: Answer Key Period:-1. State 2 similarities between Dalton’s and the Modern Day model of the atom.
For example, water is a compound made up of 2 atoms of hydrogen and 1 atom of oxygen (a ratio of 2:1). Three atoms of hydrogen and 2 atoms of oxygen cannot combine to make water. Three atoms of hydrogen and 2 atoms of oxygen cannot combine to make water.... Calculated that the atom consisted mostly of empty space through which electrons move and also concluded that there was a tiny, dense region "the nucleus" centrally located within the atom that contained all of an atom's positive charge and virtually all of its mass.
Historical Development of Atomic Theory: Aristotle to Rutherford1. Democritus and Aristotle in 400 B.C.2. Aristotle: matter can be divided into smaller andsmaller particles.3. Democritus: the atom is the smallest unit.4. Aristotle’s theory was most popular.

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Retrieved Text: Gram atomic mass & Molar mass.
First recorded evidence that atoms existed.
Dalton’s theory was based on the premise that the atoms of different elements could be distinguished by differences in their weights.
o The indivisibility of an atom was proved wrong , for, an atom can be further subdivided into protons, neutrons and electrons. o The atoms of same element are similar in all respects , but isotopes of same element have different mass.
An electron is a negatively charged component of an atom which exists outside the nucleus. Each electron carries one unit of negative charge and has a very small mass as compared with that of a neutron or proton.
Since the ray was attracted to a positive electric plate placed over the cathode ray tube (beam deflected toward the positive plate) he determined that the ray must be composed of negatively charged particles.
E. Goldstein in 1886 discovered the presence of new radiations in a gas discharge and called them canal rays. These rays were positively charged radiations which ultimately led to the discovery of another sub-atomic particle.
Canal Rays: The positively charged radiation produced in the discharge tube at low pressure and high voltage are called canal rays.
Q.1 What was the model of an atom proposed by Thomson? Q.2 What is the nature of charge on electrons?
the gold foil without getting deflected. empty.
completely rebound on hitting the gold compared to the total size.
Limitation: In Rutherford’s atomic model , Nucleus & electrons are held together by electrostatic force of attraction which would lead to the fusion between them. This

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Retrieved Text: esting relationship that exists between the electromotive series and the periodic table. ... so far from the nucleus by the fifty-four other planetary electrons of the.
Modern text-books of first-year chemistry do not emphasize an interesting relationship that exists between the electromotive series and the periodic table. In fact one of the most widely used texts in first-year college chemistry lists among the defects of the periodic system the absence of any relationship between these two important generalizations of the science. It is true the relation that may be derived from the order in which the elements stand in the two tables is limited, but it is sufficient to furnish a striking example of how our modern conceptions of the structure of atoms enable us to obtain a clearer insight into the mechanism of chemical reactions. In following our present-day practice of placing emphasis upon interpretations based on atomic structure the anthor has found this illustration very enlightening to students of first-year chemistry. Reference to a periodic table and to a table of the order of activity of the metals will show that in the alkali family the heaviest metal is the most active, the next heaviest is second in order of activity, and that this relation holds throughout this family. Immediately below lithium, the lightest and least active metal of the alkalies, we find in the electromotive series the following for the order of decreasing activity of the alkaline earth family: barium, strontium, calcium, and magnesium; turning to the periodic table we find this to he

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Retrieved Text: Molecular polarity occurs when atoms with different electronegativity rates combine in a fashion that results in an unsymmetrical distribution of electrical charge. Since all atoms have a certain amount of electronegativity, all molecules are said to be somewhat dipole. However, when a molecule possesses a symmetrical structure, the charges cancel each other out, thus resulting in a non-polar molecule. The same thing happens when all the atoms in a molecule contain the same electronegativity.
Determine each atom's electronegativity by using a periodic table of elements. If all the atoms have the same electronegativity, then the molecule is by default non-polar. Given the molecule CH4, Carbon (C) has an electronegativity of 2.5 and Hydrogen (H) has one of 2.1. Given the molecule NH3, Nitrogen (N) has an electronegativity of 3.0. However, given the molecule NCl3, Nitrogen and Chlorine both have the same electronegativity of 3.0, so the molecule is non-polar.
Draw the molecule using the Lewis dot diagram method. Count the number of valence electrons each atom contains. Arrange the atoms so that the one with the greatest electronegativity is in the center. Connect the atoms with single electron bonds and remove these electrons from the valence count. Position pairs of electrons around the outer atoms until you achieve an octet, and then remove these electrons from the count. Place any remaining electrons around the atom in the center.
Determine the molecule's polarity by inspecting its shape for symmetry. Given the example, the molecule CH4 has a tetrahedral shape that is symmetric. Thus, it is non-polar. The molecule NCl3 has

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Retrieved Text: Questions and Answers - How do I read an electron configuration table?
Are you making a model of an atom and need to know how to place the electrons around the nucleus? If so, you will need to know how to read an element's electron configuration table. Follow these easy directions to learn how!
What is an electron configuration table?
The first number is the energy level. We can tell right away that an atom of gold contains 6 energy levels.
The lowercase letter is the sub-shell. The sub-shells are named s, p, d and f. The number of available sub-shells increases as the energy level increases. For example, the first energy level only contains an s sub-shell while the second energy level contains both an s sub-shell and a p sub-shell.
The number in superscript is the number of electrons in a sub-shell. Each sub-shell can hold only a certain number of electrons. The s sub-shell can hold no more than 2 electrons, the p sub-shell can hold 6, the d sub-shell can hold 10 and the f sub-shell can hold as many as 14.
How many energy levels does an atom have?
How many electrons are in each energy level?
How many electrons are in an atom's outer energy level?
Video - How to Draw an Atom!

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Retrieved Text: This is “Multiple Covalent Bonds”, section 4.3 from the book Introduction to Chemistry: General, Organic, and Biological (v. 1.0). For details on it (including licensing), click here.
Recognize molecules that are likely to have multiple covalent bonds.
This does not give the carbon atom a complete octet; you will find only six electrons in its valence shell. In addition, each oxygen atom has only seven electrons in its valence shell. Finally, no atom makes the number of bonds it typically forms (Figure 4.2 "How Many Covalent Bonds Are Formed?"). This arrangement of shared electrons is far from satisfactory.

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Retrieved Text: When an electron is free to assume higher energy states around an atom's nucleus (due to its placement in a particular "shell"), it may be free to break away from the atom and comprise part of an electric current through the substance. If the quantum limitations imposed on an electron deny it this freedom, however, the electron is considered to be "bound" and cannot break away (at least not easily) to constitute a current. The former scenario is typical of conducting materials, while the latter is typical of insulating materials.
Some textbooks will tell you that an element's conductivity or nonconductivity is exclusively determined by the number of electrons residing in the atoms' outer "shell" (called the valence shell), but this is an oversimplification, as any examination of conductivity versus valence electrons in a table of elements will confirm. The true complexity of the situation is further revealed when the conductivity of molecules (collections of atoms bound to one another by electron activity) is considered.
A good example of this is the element carbon, which comprises materials of vastly differing conductivity: graphite and diamond. Graphite is a fair conductor of electricity, while diamond is practically an insulator (stranger yet, it is technically classified as a semiconductor, which in its pure form acts as an insulator, but can conduct under high temperatures and/or the influence of impurities). Both graphite and diamond are composed of the exact same types of atoms: carbon, with 6 protons, 6 neutrons and 6 electrons each. The fundamental difference between graphite and diamond being that

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Retrieved Text: Home › Kilted Suds ~ The Dirty Truth › What Are Free Radicals?
Usually when people ask me how I make my soap, my first response is "Very Carefully!" The truth of this process is actually quite simple, it's a lot of chemistry, a lot of formulas, a lot of trial and error, and a lot of practice. Why am I talking about chemistry? Simple, free radicals are all about chemistry too!
Let's put this in simpler terms: a free radical is an atom (or group of atoms) that has an unpaired electron and is therefore unstable and highly reactive. To fully understand what this means, you must have a basic knowledge of chemistry. High school chemistry (Ugh!) taught us that our bodies are all composed of a myriad of different cells, each consisting of multiple atoms and/or elements which are joined by chemical bonds. Each atom consists of a nucleus, neutrons, protons and electrons, protons being positive, electrons being negative. The number of protons in the atom's nucleus directly determines how many electrons surround the atom. The electrons are the part we are focused on. Electrons are responsible for bonding one atom to another to create molecules. Electrons orbit an atom in "shells". Each shell can hold a certain number of electrons before it is considered full and the next shell begins to fill. The first shell holds 2 electrons, the second holds eight, and so on.
It is the number of electrons in an atom's outermost shell that determines its chemical behavior. Atoms by nature want to

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Retrieved Text: Electron dot diagrams, sometimes called Lewis dot diagrams, were first used by Gilbert N. Lewis in 1916. These diagrams are used as a shorthand notation to show the number of valence electrons in an atom. More complicated versions can be used to show the bond between different atoms in a molecule.
Write the symbol of the atom you are drawing the electron dot diagram for in the middle of your paper. This symbol represents the nucleus of the atom and each of the four sides represents an orbital.
Locate the element you are drawing an electron dot diagram for on the periodic table of elements. Find the number of electrons in one atom of the element. The number of electrons is the same as the element's atomic number.
Find the number of valence electrons by subtracting the number of electrons in each level from the total number of electrons. There are two electrons in the first level and eight in the second, third and fourth levels. The diagram will represent only the outermost level of the electron field. Take the number of electrons and subtract the number of electrons in each level until you come to a level that is not entirely full. For the noble gases, the last level will be full, with no electrons left over, and this is the level you will draw.
Place the first two dots on the right side of the element symbol. This side is referred to as the s orbital.
Place the remaining dots in a counterclockwise fashion around the edges of the

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Retrieved Text: According to Bohr’s atomic model, the electrons revolving around the nucleus are governed by a definite path and hence have a definite energy level so the electrons in an atom have well-defined energy levels.
When the atoms are brought close to each other, they begin to influence each other due to mutual interaction between them. This mutual interaction is more in case of outer shell than the inner shells.
If we take silicon as an element which is a semi-conduct with electronic configuration of 152 252 2P6 352 3P2. Since the crystal contains at least 1023 atoms per unit volume so there may be at least 1023 sub-levels which are created. These sublevels lie very close to each other and hence they are known as the energy band.
When separation is d1, the electrons in the outer-most shell of one atom do not interact with the electrons in the atoms the other due to large separation so, at this stage, each atom has its own specified energy level.
When separation is d2, the inter-atomic separation is less, so the electrons in the outermost shell start interacting with another due to which the modification of levels start (3s and 3p) levels, but still at this stage, energy gap occurs.
When separation is d3, inter-atomic separation reduces further and the independent 3s and 3p levels disappear. They are now distributed in a continuous manner, hence forming an energy band.
When separation is r, the atoms are at there actual inter-atomic separation due to which the energy band splits up into two levels with a

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Retrieved Text: An atom is the smallest particle of matter that can combine chemically with another atom or molecule. It has a nucleus, composed of protons and neutrons, around which electrons orbit.
The electron carries a charge equal to the proton but opposite in charge (-e).
An atom has as many protons as electrons. The total charge is zero which is why matter is usually neutral.
In some cases, with the help of an external energy input, an atom can lose or gain one or more electrons. This is the phenomenon of ionization.
Example: An atom of sodium (Na) has 11 protons and 11 electrons. If it loses an electron, it then has 11 protons but only 10 electrons. A positive charge +e is no longer balanced and the resulting sodium ion is positively charged. The sodium ion, Na+, indicates that it carries a charge +e.
A molecule is an assembly of atoms that share electrons to achieve greater stability.
Click on one of the four active zones to start the animation.
To know the structure of an atom and a molecule.
To define an electrical charge.
To understand the phenomenon of the ionization of an atom.
To know the difference between a valence electron and a free electron.
To recognize two types of atomic bonds.

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Retrieved Text: Aristotle, the Greek philosopher believed that all matter was made up of four elements. Which one of the following was not one of these elements?
the particles spread out and mingle with each other.
the particles always come together to react and form a new substance.
the atoms making up the gases break apart and spread as far apart as possible.
the particles move in a well-defined pattern of motion.
Which one of the following is an example of diffusion?
When diffusion occurs between two gases such as hydrogen (red) and helium (green), which of the following diagrams best represents what is most likely to occur?
In the early 1800s, an English chemist John Dalton proposed an Atomic Theory consisting of a number of assumptions. Four of these assumptions are given below.
Which one of these is no longer known to be true?
Around the 1870s, this scientist studied mysterious rays in sealed glass tubes.
Which one of the following statements is NOT true about the atom?
Atoms of the same element may have different numbers of protons.
Atoms are the smallest part of an element that still retain the properties of that element.
Not all atoms contain neutrons.
In the Maltese Cross experiment performed by William Crookes, which one of the following is not true?
All of the electrons leaving the cathode are absorbed by the Maltese cross.
Electrons leave the cathode under a very high voltage.
This experiment shows that cathode rays travel in straight lines.
A fluorescence appears on the far end of the screen where the cathode rays strike the tube.
Select two answers and click on the Check button.
The nucleus

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Retrieved Text: principle that relates to electron energies.
separation for two atoms or ions.
separation and the bonding energy.
hydrogen, and van der Waals bonds.
protons and neutrons within the nucleus.
atomic masses, which are called isotopes.
 Electrons are assumed to revolve around the atomic nucleus in discrete orbitals, and the position of any particular electron is more or less well defined in terms of its orbital.
 Another important quantum-mechanical principle stipulates that the energies of electrons are quantized; that is, electrons are permitted to have only specific values of energy. An electron may change energy, but in doing so it must make a quantum jump either to an allowed higher energy (with absorption of energy) or to a lower energy (with emission of energy). Often, it is convenient to think of these allowed electron energies as being associated with energy levels or states. These states do not vary continuously with energy; that is, adjacent states are separated by finite energies.
- values of energy that are permitted for electrons.
 Bohr model was eventually found to have some significant limitations because of its inability to explain several phenomena involving electrons. A resolution was reached with a wave- mechanical model, in which the electron is considered to exhibit both wavelike and particle-like characteristics. With this model, an electron is no longer treated as a particle moving in a discrete orbital; but rather, position is considered to be the probability of an electron’s being at various locations around the nucleus. In other words, position is described by a probability distribution or electron cloud.
 Using wave mechanics,

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Retrieved Text: Number of protons present in nucleus of atom of an element is known as atomic number.
Mass number is also known as atomic mass. Atomic number or mass number is equal to number of protons and neutrons in atom.
Atoms of same elements which have same atomic number but different mass number is called isotopes.
example : Protium, Deutrium, Tritium are isotopes of hydrogen.
Atoms of different elements which have similar atomic mass and different atomic number are called isobars.
In 1921, Bohr and Bury gives some laws for distribution of electrons in various orbits, which are called as Bohr-Bury Scheme.
1. Maximum number of electron in any shell should be 2n2 , where n is serial number of shell.
2. Maximum number of electron that exist in outermost shell or orbit of any atom is eight while maximum number is eighteen for penultimate shell.
3. According to this law, it is not necessary that another shell is formed after completion of 1st shell. A new shell is formed as number of electrons reaches eight in any orbit or shell.
Outermost incomplete shell of any atom is known as Valence Shell and electron present in incomplete outermost shell are known as Valence Electrons , which participate in formation of bond.

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Retrieved Text: The Atomic Age. The Rutherford-Bohr model of the atom. An atom's nucleus. Electrons. Whether this hat makes you think of chemistry, particle physics, or the second half of the 20th century, it has a place in your geeky wardrobe. The sun may be 93 million miles away, but everyone needs protection from it.
This ThinkGeek exclusive men's six-panel hat is black with the ThinkGeek logo embroidered on the back and a yellow atomic model embroidered on the front, a symbol of the Atomic Age. Its snapback is adjustable for a custom fit. One size.

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Retrieved Text: Periodic table[ edit ] Electron configuration table The form of the periodic table is closely related to the electron configuration of the atoms of the elements. Phosphorus, for instance, is in the third period.
Pauli-Exclusion Principle Wolfgang Pauli postulated that each electron can be described with a unique set of four quantum numbers. The electron configuration can be visualized as the core electronsequivalent to the noble gas of the preceding periodand the valence electrons: It is possible to predict most of the exceptions by Hartree—Fock calculations,  which are an approximate method for taking account of the effect of the other electrons on orbital energies.
Nitrogen, for example, has 3 electrons occupying the 2p orbital.
In bulk materials, this idea helps explain the peculiar properties of lasers and semiconductors. That is, we follow the three important rules: For atoms, the notation consists of a sequence of atomic subshell labels e.
It may be stated as: However, the energy of an electron "in" an atomic orbital depends on the energies of all the other electrons of the atom or ion, or molecule, etc. Hund's Rule Hund's Rule states that when electrons occupy degenerate orbitals i.
The electronic configuration for Cl- can, therefore, be designated as 1s22s22p63s23p6. The fact that the Aufbau principle is based on an approximation can be seen from the fact that there Atom and electron configuration an almost-fixed filling order at all, that, within a given shell, the s-orbital is always filled before the p-orbitals.
If that were the case, the 3d-orbital would have the same energy as the 3p-orbital,

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Retrieved Text: Semiconductors are utilized widely in electric circuits. As its name signifies, a semiconductor is a component which carries out electric power, but only partially. The conductivity of a semiconductor is someplace in between that of an insulator, that has basically no conductivity, and a conductor, that has basically complete conductivity. Many semiconductors are crystals made from specific components, many generally silicon.
To comprehend how semiconductors function, you should initially comprehend a little about how electrons are arranged in an atom. The electrons in an atom are arranged in layers. These layers are known as shells. The outer shell is known as the valence shell.
The electrons within this shell are the ones which form bonds with surrounding atoms. This type of bonds are known covalent bonds. Many conductors have only one electron in the valence shell. Semiconductors, however, generally have 4 electrons in their valence shell.
it is feasible for all the valence electrons to connect with valence electrons coming from other atoms if all the surrounding atoms are of the exact same type. The atoms organize on their own into structures known crystals while that occurs. Semiconductors are produced of such crystals, generally silicon crystals.
Right here, each circle stands for a silicon atom, and the lines in between the atoms stand for the shared electrons. Each of the 4 valence electrons in each silicon atom is provided one surrounding silicon atom. Hence, every silicon atom is bound with 4 other silicon atoms.
Pure silicon crystals aren’t all that effective digitally. If you present little quantities of other elements into

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Retrieved Text: UNDERNEATH ALL REALITY is broiling and industrious machinery. An atom is not a static structure ; it is a nano-machine. Everything within it—electrons, protons, neutrons, quanta—is moving and interdependent. Holding atomic machines together while the parts move about at thousands of miles per hour are strong and weak forces in the nucleus, and electromagnetic forces between electrons in their shells and the nucleus.
An atom has plenty to occupy it just going about its business being what it is. It is not thinking about becoming something else unless it is tinkered with. If the nucleus is bombarded with radiation it may start to decay (the entire nuclear industry is based upon such nuclear changes). If electrons are added or taken away, the atom's resulting imbalance will cause it to seek out ways to restore balance by combining with other atoms that may have too many or too few electrons (the entire chemical industry is based upon this). But such things are just normal social behavior of atom machines and are what they must do to keep running and be happy. We cannot get overly enthusiastic, implying evolution, and construe from this behavior that an atom wants to become part of a novel, painting, computer, or amoeba.
The same machine principles apply to proteins, nucleic acids, lipids, organelles, cells, and organisms. They are all machines with trillions of moving parts. Their goal is to stay running and keep their parts together. Homeostasis is their desire, not transmutation (evolution). A protein machine does not want to become a muscle machine,

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Retrieved Text: This chapter lays the foundation for your understanding of electronics. This unit introduces you to the fundamental concepts, terms, and units of measures common to all electronics technology. The material presented forms the basis for all subsequent studies in electronics. The information here in chapter two is very foundational to your understanding of electronics.
First of all, we're going to look at atomic structure. All matter is composed of increasingly smaller building blocks. Those building blocks are and there's a mention here of the building blocks of matter. I'm going to let you read through the first few here. If you want to press your pause button and stop and read through those, please go ahead. I'm going to pick up on down here at electrons. Electrons, negatively charged particle orbiting the nucleus of all atoms. That's what an electron is. A proton, positively charged particle in the nucleus of all atoms. A neutron, atomic particle having no charge located in the nucleus of an atom.
Below is a hydrogen atom. Atoms can be viewed as a miniature planetary system, similar in concept to our solar system. Here we have a single hydrogen atom and here is a large one. You get the idea here of a miniature planetary system. Each atom has a dense nucleus, which contains the protons and the neutrons. This is this area right here. Electrons orbit the nucleus of an atom. Notice here the electrons orbit the nucleus of an atom and an electron has a minute mass compared to the nucleus. A

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Retrieved Text: semiconductor is like that of an insulator. The main difference is that the semiconductor has a much smaller energy gap EI/ between the top of the highest filled band (called the valence band) and the bottom of the vacant band just above it (called the conduction band). Thus, there is no doubt that silicon (Ell = 1.1 eV) is a semiconductor and diamond (Ell = 5.5 eV) is an insulator. In silicon-but not in diamond-there is a real possibility that thermal agitation at room temperature will cause electrons to jump the gap from the valence band to the conduction band. In we compared three basic electrical properties of copper, our prototype metallic conductor, and silicon, our prototype semiconductor. Let us look again at that table, one row at a time, to see how a semiconductor differs from metal.
silicon in which the portion has J.ee projecte4 ont8 a ,Jane; compare the figure with which represents the unit cell of the lattice in three lIimensions. Each SiliCORatom c contributes its pair of 3s electrons and its pair of 3p electrons to form a rigid two-electron covalent “nd with each ef its four nearest neighbors. (A covalent bond is a link between two atoms in which the atoms share a pair of electrons.) The four atoms that lie within the unit cell in show these four bonds. The electrons that form the silicon-silicon bonds constitute the 1’llle1¥’eHnjof the silicon s.mplt. U an e\ectrot\ is tom ftOm one of these ~ends so that it some free to wander throughout the

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Retrieved Text: the smallest particle of an element is called an ____.
an ____ is a charged atom or molecule.
acid ____ is caused by pollutants that combine with water in the air.
____ is anything that occupies space and has mass.
2 or more atoms held together by covalent bonds form a ____.
neutrons and protons are found in an atom's ____.
the cohesion of water molecules is responsible for ____.
variant forms of an element with different numbers of neutrons are called ____.
____ is the tendency of water molecules to stick together.
a ____ is a subatomic particle with no electrical charge.
____ measures the intensity of heat.
electrons are shared unequally in a ____ covalent bond.
there are 92 naturally occurring ____.
a ____ contains 2 or more elements in a fixed ratio.
weak bonds between water molecules are called ____.
an ____ donates H+ ions to solutions.
a ____ is formed when 2 atoms share electrons.
a ____ is a positively charged particle from the nucleus of an atom.
in a solution, the dissolving agent is called the ____.
a ____ is liquid containing a uniform mixture of substances.
when 2 ions of opposite charges attract each other, an ____ forms.
the ____ is the substance dissolved in a solution.
a ____ accepts H+ ions and removes them from solution.

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Retrieved Text: For further discussion, see also Theoretical chemistry and Quantum chemistry.
In chemistry, a chemical bond is an arrangement of electrons among atoms that keeps the atoms together. The bond originates in the electrical attraction of opposite charges, and is made possible by the attraction of the positive nucleii of atoms to the electrons associated with them. The central issue in understanding the bond is finding how the electrons associated with atoms distribute their negative charge so as to overcome the natural repulsion between positive atomic cores. A useful understanding can range from an entirely qualitative model based upon the attraction of one atom for electrons compared to another (their electronegativity) to very detailed computer calculations based upon quantum mechanics.
If the total energy of two or more bound atoms is lower than the sum of the energies of the free component atoms, the aggregate of atoms form a stable molecule (or crystal) and the energy lowering is the binding energy of the molecule (or crystal).
The chemical bond takes on many forms, ranging from simple atomic pairs in a diatomic molecule, to large organic molecules like DNA. Examples of atomic pairs are two nitrogen atoms chemically bound to the stable dinitrogen molecule (written as N2) and a hydrogen atom with a fluorine atom forming hydrogen fluoride (HF). As an example of larger complexes, carbon (C) and oxygen (O) form the pair C—O that appears in many organic molecules, one of the simplest being methanol H3C—OH. Atoms may also be bound to form a crystal, such as sodium (Na) and

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Input Text: Read the passage below and choose the right answer to the following question (choices are SPF 30 or SPF 100 ):

A sunscreen with a higher SPF value protects the skin longer.


Allie looks for sunscreen at the store. She sees SPF 30 and SPF 100. Which likely protects her skin worse SPF 30 or SPF 100?

Target Text: SPF 30

#### Retrieved Documents ####

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Retrieved Text: Sunscreen 101 — What Do SPF Numbers Mean?
In the past, you may have been told that SPF numbers were relatively simple to understand. If you can be out in the sun for 10 minutes with unprotected skin before your skin would begin to burn, the explanation went, then with an SPF 15, you could stay in the sun 15 times as long, or 150 minutes before you would burn. Simple, right? Not so fast, the science behind SPF is actually quite detailed, and sunscreens should be reapplied every 2 hours, regardless of the SPF.
1. Look for Broad Spectrum coverage. While we generally apply sunscreen in the summer to avoid a sunburn, UVA rays are present year-round, and those are the rays that have an aging effect on the skin. To keep your skin looking its best, as well as avoiding an increased risk of skin cancer, you want protection from UVA rays and UVB rays which is what Broad Spectrum protection offers.
2. Go for SPF 30 to 50. Even if you had SPF 100, it wouldn't protect you from 100% of the sun's rays, so looking for that sort of protection is not necessary. SPF 15 protects you from slightly more than 93% of the sun's UVB rays. SPF 30, even though it LOOKS like it offers double the protection of SPF 15, protects you from nearly 97% of the UVB rays. As the SPF goes up, the percentage of protection increases only slightly--when you jump up to SPF 50, the increase in protection is even

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Retrieved Text: Now that Summer is in full swing, it’s especially important to keep your skin protected from the sun’s UVA/UVB rays, which can cause premature skin aging, skin cancer, sun spots, and more!
With so many chemical ridden sunscreen formulas on the market, it can be overwhelming to choose the one that you think will be right for you. And if you’re still confused about the difference between chemical and physical formulas, check out our blog post that breaks down the difference! In short, physical formulas are most gentle on your skin because they lack common chemical irritants that can cause skin inflammation and even disturb oceanic ecosystems.
This week, we’ve partnered with DIY Beauty Expert, Alexandra Potora to make her own all-natural, and 100% non-toxic physical sunscreen using our wholesome ingredients and tried and true recipe!
Follow Alexandra on Instagram and subscribe to her YouTube Channel for more DIY beauty videos!
Watch the tutorial below or print out the recipe to follow along!
Mango Butter: Moisturizes and keeps your skin soft.
Zinc Oxide: protects naturally against UVA and UVB -- 2 tablespoons for SPF 15 protection. Protects against 93% of UVB rays.
SPF 30 protects against 97% of UVB rays, whereas SPF 15 protects against 93% of UVB rays. It is commonly known that if applied frequently there isn't much of a difference between SPF 15 and 30.
1.Melt the Mango Butter, the Oil using the double boiler method and stir.
2. Remove from the heat when all ingredients have melted.
3. Slowly add the Zinc Oxide and continue stirring.
4. Store in a cool place.
This formula

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Retrieved Text: He says protecting your body from the sun is a whole package deal. But the FDA says there's no evidence such products provide better protection against harmful rays-and they may actually make us feel overconfident and less likely to reapply.
Still have last year's bottle of sunscreen? But only to the level of an SPF 4, which gives you protection for about 45 minutes.
One of the issues of disagreement is that even though the FDA contends that products labeled with SPF higher than 50 are "inherently misleading", they have not mandated that producers of sunscreen refrain from labeling their product with values above this. "But this is probably my biggest beef with the sunscreen industry", Lunder tells Fast Company.
Apply sunscreen 30 minutes before going outside. Because there is no justified reason to use products with a higher SPF, then using said products only puts the person in an unnecessary degree of risk.
An estimated 5.6 million Americans will confront skin cancer in 2017.
The Food and Drug Administration has yet to decide whether it will stop allowing sunscreen manufacturers to market their products with SPF numbers higher than 50, even though sunscreens with 90 and 100 SPF coverage often offer similar protection as those that are SPF 50, Lunder said.
"This year, we estimate that almost every sunscreen we reviewed passes the FDA test", the EWG researchers write, "but that about half of them would not offer enough UVA protection to be sold in Europe".
Over the past three decades, more people have had skin cancer than all other cancers combined.

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Retrieved Text: When you’re faced with lots of sunscreen options, it’s easy to be overwhelmed by all the different types and brands. But the first thing that really matters is the SPF.
Let’s talk about what is the minimum SPF you should be reaching for next time you buy sunscreen.
When looking at a sunscreen bottle, we know a high SPF is good, but maybe not why it’s good. By understanding what SPF measures, we can decide how much is right for us.
SPF is an acronym for Sun Protection Factor, a measurement of how long it takes someone to burn with and without the sunscreen. This is learned by applying the product on a participant and comparing the length of time it takes protected and unprotected skin to burn under a UV lamp.
An SPF of 10, for example, means that it took participants in that sunscreen’s tests 10 times longer to burn while wearing it and thus protects from 90% of sunburn-causing UVB rays.
Obviously, the higher the SPF, the longer you could theoretically go without burning and the more protection you are getting from damaging UV rays.
So what SPF is enough?
The FDA seems to think that SPF 15 is required according to its sunscreen regulations, but most dermatologists and skin cancer specialists conclude that SPF 30 is the minimum to truly protect against damage. Those with lighter skin tones are advised to wear higher SPF sunscreen and to wear it and reapply it more often.
Another thing to consider is whether or not the sunscreen is broad spectrum. This is where

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Retrieved Text: Q: What exactly are UV rays?
Exposure to UV radiation is a major factor in most skin cancers, and most UV radiation comes from the sun! You are also exposed to UV rays in tanning beds.
UVA rays age skin cells. They're linked to skin damage like wrinkles, but can also cause skin cancers (especially from tanning beds, which produce a lot of UVA rays and have been linked to skin cancer).
UVB rays are the main rays that cause sunburns and are believed to cause most skin cancers.
Avoid the sun between 10 a.m. and 4 p.m. UV rays are strongest between these times. Wear sunblock and cover your skin even if you're skitting in the shade or it's cloudy -- UV rays can reflect off of many surfaces and can sometimes be amplified by cloud cover. Staying in the shade and cloudy days mean you'll be less exposed to UV rays, but using sunblock is your best bet when it comes to protecting your skin.
The American Cancer Society suggests broad spectrum (this means it protects against UVA AND UVB rays), water-resistant sunblock that has not expired.
Sunscreen labeled with SPFs as high as 100+ are available. Higher numbers do mean more protection, but many people don’t understand the SPF scale. SPF 15 sunscreens filter out about 93% of UVB rays, which SPF 30 sunscreens filter out about 97% , SPF 50 sunscreen about 98%, and SPF 100 about 99%. The higher you go, the smaller the difference becomes. No sunscreen protects you completely. Sunscreen with an SPF lower than

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Retrieved Text: LOS ANGELES Gia Alexi-Tomari wants to look her best and wonders whether her age is starting to show.
"I worry quite a bit about wrinkles and getting older," said Gia.
She uses a sunscreen that says it has special anti-aging ingredients. Gia says she sees a visible difference.
"The skin tone is much smoother and the texture is a lot firmer," said Gia.
Sunscreens by nature have anti-aging effects because they block damaging /*UV rays*/. But now, new products are promising even more and acting more like high-end skin care. They've added ingredients like retinol, peptides and plant extracts to fight wrinkles and stimulate collagen production.
"We're talking about adding a primarily antioxidant, or a skin protein maybe from a fetal skin cell, added to the sunblock, which also counteracts free radical formation, which also causes aging," said dermatologist Dr. Dina Anderson.
It's the free radical formation that causes wrinkles, loss of skin firmness and an uneven skin tone.
Dr. Anderson says studies show some of the ingredients may live up to the claims, but before you pay for new protection, you should look for some scientific backing instead of just a commercial claim.
"You might want to do some investigating on the Internet into some of the research that has been done," said Dr. Anderson.
Even then, you have to be careful about what you cover and how often.
"You need to reapply them every two-to-three hours," said Dr. Anderson. "Even more frequently if you're going to be in the water."
Gia puts on her sunscreen first thing in the morning, and then reapplies a couple

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Retrieved Text: For babies 6 months and older, or anyone in search of an ultra-gentle, fragrance-free mineral SPF stick.
Your little one's skin needs extra TLC. Our Mineral Baby SPF 50 Unscented Moisturizer is our purest lotion sunscreen, designed to safeguard the most precious and delicate skin.
People who love both makeup and great sun protection, and want to reapply SPF without it messing up their makeup, this is what you've been waiting for!
Protect your pucker with our Liplux® SPF 30 balm. This vitamin-enriched, antioxidant formula protects and conditions lips with a Peppermint Vanilla flavor.
Like FaceTune in a bottle, our Classic SPF 30 Dawn Patrol Makeup Primer helps your complexion look softer, smoother, and brighter—with or without makeup.
For anyone with dry, sunburned or just plain thirsty skin morning, noon and night.
Everyone needs a good A.M. moisturizer with sunscreen!
Mineral SPF shouldn't ghost you—this one nourishes and protects without leaving any white residue on your skin. SPF 30 moisturizing mineral sunscreen with antioxidant benefits.
This all-in-one lip treatment moisturizes and protects with broad spectrum UVA/UVB SPF 30 protection. This product is unscented, but you’ll still want to say MUAH!
Travelers or anyone who wants mini sizes of our mighty sun products. A pouch with four essential TSA-friendly size products inside!
Sun's out, fun's out! Our spray-on sunscreen is sheer with good-for-your-skin ingredients, plus it's organic SPF 30 and the perfect petite size to take with you.
Organic fans who love the outdoors! This is a broad-spectrum, SPF 50 moisturizing lotion sunscreen with antioxidants for enhanced UV protection.
Sun's out, fun's out! A sport sunscreen doesn't have to

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Retrieved Text: Steps Every Man Needs to Follow When Applying Sunscreen.
Using sunscreen might not be as simple as you think: Most people hold inaccurate beliefs about their sunblock, new research from the American Academy of Dermatology (AAD) suggests.
And these misconceptions might leave you at greater risk of developing skin cancer.
In the survey, only 32 percent of respondents knew that an SPF 30 sunscreen does not provide twice as much protection as an SPF 15 sunscreen does.
In fact, the increase in protection from an SPF 15 to an SPF 30 isn’t very significant.
An SPF 30 blocks 97 percent of sunburn-causing UVB rays, while an SPF 15 blocks 93 percent, says Josh Zeichner, M.D., a spokesman for the AAD.
That means an SPF 30 blocks only 4 percent more UVB rays than SPF 15 does, a far cry from the “double” the numbers behind them would have you believe.
What’s more, just under half of those surveyed knew that a higher SPF sunscreen doesn’t protect you from the sun for a longer time than a lower SPF one does.
The real deal: Any sunscreen, no matter the SPF, wears off after two hours.
Putting too much faith in high SPF—whether it’s for amount of protection or how long you can safely stay in the sun—can be dangerous, since it can lead to a false sense of security regarding your burn risk, says Dr. Zeichner.
That may mean you might be more likely to stay in the sun for longer than you should or put off reapplying more sunscreen, which can make you more likely to

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Retrieved Text: Easy sun protection tips with your loved ones this summer.
A video that shows exactly why we need to wear sunscreen.
“Yeah it is,” I agreed.
Just as an FYI, you should know that this post is sponsored by Nivea. But all opinions expressed by the author are 100% authentic and written in their own words.
As a child I roamed the NSW countryside with, maybe, one coat of SPF15. We never reapplied it and I now have arms covered in freckles and an aging face of pale skin as a constant reminder of my childhood.
In recent years we’ve been told to use sunscreen to protect ourselves from the harsh Australian sun, but do we really understand why? It wasn’t until I watched this video that I really understood it.
Filmed here in Australia, this clip shows exactly why we need to wear sunscreen – because the sun sees our skin differently when we apply it. Once you’ve seen the clip (I dare you not to watch it at least five times, it’s so fascinating) you truly can see how the sunscreen we use acts as a barrier helping to protect our skin from damage.
As someone with pale skin I’m constantly keeping up with skin care and sunscreen recommendations. I’m also constantly informing my friends and family about the difference between SPF 50 and SPF 30. The SPF (Sun Protection Factor) has absolutely nothing to do with strength but rather the amount of time you are protected.
Say you have pale skin like I do and you start to burn within three

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Retrieved Text: this product provides the safest and easiest way to defend skin against uva, uvb and infrared rays while protecting delicate elastin protein from breaking down. it is gentle enough for acneic skin and even retinol users.
SheerZinc SPF 30 is a sunscreen that not only softens signs of aging but also has a restorative effect on your skin’s previous sun exposure. this 100% physical sunscreen is light enough to wear under makeup and harnesses the power of zinc oxide to guard and protect your skin; this mineral based sunscreen absorbs quickly, working to elegantly shelter your skin.
best for: SheerZinc SPF 30 is appropriate for all types of skin, however particularly effective for sensitized and acne prone skin.
apply to the face, neck, and décolleté as desired throughout the day.
SheerZinc SPF 30 protects both elastin and skin proteins from harmful uv damage and collagen breakdown. ensuring uva and uvb protection, while providing a translucent glow.
Stem Cell Rebuilding Complex addresses compromised, fragile or maturing skin by restoring crucial hydration, fortifying the epidermis and stimulating collagen production for increased firmness.
Solar Moisturizer SPF 30 offers a dual chemical spf and moisturizer protect elastin protein from uv damage while plumping peptides encourage more youthful looking skin.

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Rank: 10
Score: 64.39373
Retrieved Text: When it comes to the SPF number on our sunscreen bottles, most people shrug and grab the highest one, figuring bigger is better.
SPF 30? 50? 75? Bring it on—it will work, right?
There's actually much more to it than that, and it's all rather scientific. Simply put, SPF, or Sun Protection Factor, is a measure of how well a sunscreen will protect your skin from UVB rays.
Two kinds of UV radiation—UVA and UVB—can damage the skin. UVB rays are usually the culprit behind those pink, peeling sunburns, but UVA rays can be just as problematic. We have UVA rays to thank for wrinkles and leathery, saggy skin.
Wearing sunscreen with an SPF rating gives you a certain amount more time of safe sun exposure. It's fairly simple to calculate how long you can stay in the sun safely, as long as you know the SPF number and how long it takes you to develop a sunburn normally.
To calculate the safety of your sunscreen, multiply the number of minutes you can sit outside without burning by the SPF number. For example, if you would normally burn after 10 minutes in the sun, applying sunscreen with an SPF rating of 15 would allow you to stay in the sun safely for about 150 minutes. Of course, this is a rough estimate, and it really depends on your skin type, the amount of sunscreen you use, and the intensity of the sunlight you’re in.
Interestingly, the SPF scale is not linear. Contrary to what you might think, upgrading from SPF 15 to

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Rank: 11
Score: 63.876743
Retrieved Text: What SPF sunblock should you buy, SPF 15, 30, 60 or greater?
Use of Sunblock creams or sunscreens is now popular amongst both male and female sexes. When you go to a dermatologist or cosmetician to have an opinion about better skin care management, they will tell you to use a sunblock whenever you go out in the sun. When you go to a shop to buy a sunscreen, you don’t know what SPF sunblock should you buy?. You fear that an SPF 15 sunblock is nothing in front of SPF 50 or 90 sunblock, then you also worry about the cost of a high SPF sunblock.
Sun rays contain ultraviolet radiations that have the tendency to damage your skin. Our skin has the ability to resist this damage for a few minutes to an hour depending upon the colour of the skin. Dark coloured individuals tend to withstand the sunlight for a longer period of time as compared to a fair coloured individual. White skinned individuals more commonly complain of sun damage, rash, pimples and acne as compared to dark skinned individuals.
Why do the dark colored individuals withstand sunlight better?
Cosmetologist encourages the use of sunblock in adults when they go out in the sun. When you buy a sunscreen or sunblock cream, you see a special value on the pack represented by SPF. You may see various values of SPF, maybe 15, 24, 30, 40, 45, 60 etc. SPF stands for sun protection factor. The higher the value better will be the protection. For instance, a 15

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Rank: 12
Score: 63.752148
Retrieved Text: Is Makeup With Sunscreen Enough to Protect Your Skin?
Many foundations and powders contain sunscreen, but is it enough for daily protection?
You want to prevent wrinkles and skin cancer, so you are dedicated to wearing sunscreen. But coverage looks shiny or chalky, especially under makeup.
Many foundations and other makeup products offer a built-in sun protection factor (SPF). Is that your smartest beauty solution? Dermatologist Leslie Baumann, MD, says giving in to that temptation would be a mistake.
"Makeup does not provide enough coverage," she says. "You need seven times the normal amount of foundation and 14 times the normal amount of powder to get the sun protection factor on the label. No one does this."
So can you marry makeup and sunscreen in your routine and still look good? Yes, if you follow these steps.
1. Select the proper sunscreen.
Before you step in front of the bathroom mirror, find a sunscreen that offers enough protection. The Skin Cancer Foundation advises people to use a moisturizer containing broad-spectrum sunscreen (which means it blocks both UVA and UVB rays) with an SPF rating of at least 15. Ingredients such as zinc oxide, avobenzone (Parsol 1789) or ecamsule (Mexoryl), combined with octocrylene and avobenzone work best with makeup and provide broad spectrum sun protection.
Baumann says to layer a physical sunscreen, such as Aveeno Ultra-Calming Daily Moisturizer SPF 15, with a chemical sunscreen (either Topix Glycolix Elite Sunscreen SPF 30 or Blue Lizard Australian Sunscreen Sensitive Skin SPF 30), to block most of the sun’s rays.
Tina Turnbow, makeup artist, advises using a natural moisturizer,

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Rank: 13
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Retrieved Text: Sunlight is strongest when it is directly above the sky. This is why health professionals advise that a person must avoid the sun between ten o’clock in the morning to four o’clock in the afternoon. A marathon conducted at exactly twelve noon not only plays havoc on the skin, but also causes heat stroke and dehydration.
If going out in the sun is unavoidable during such hours, a person should wear protective clothing. Protective clothing can reduce the skin’s exposure to sunlight. Long pants protect the legs. Long-sleeved shirts protect the arms. And broad-brimmed hats can protect the face, especially the eyes. Umbrellas are also effective tools in reducing sun exposure.
A sunburn is an actual burn of your skin from the ultraviolet (UV) light from the sun or other UV light sources (ie tanning beds). A sunburn can occur from as little as 15 minutes of midday sun exposure in a very light-skinned person.
The first signs of a sunburn may not appear for a few hours after the UV exposure. Sunburns may often appear “worse” the day after being at the beach, as it can take 24 hours or longer for the full effect of the UV damage to your skin to appear.
Sunburned skin is red and tender skin that is warm to the touch. Severe sunburned skin may result in the formation of blisters. Almost all sunburned skin will result in skin peeling on the burned areas several days after the sunburn.
Take anti-inflammatory medications such as ibuprophen (Advil, Motrin), naproxen (Aleve) or aspirin. Do NOT give

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Rank: 14
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Retrieved Text: Dear Science: What does sunscreen SPF mean, and what happens if you mix them?
Dear Science: I'm gearing up for a summer vacation, and I've been burned before — so I want to make the most of all these half bottles of sunscreen left in my cabinet. If you mix equal amounts of SPF 10 sunscreen and SPF 30 sunscreen, do you get SPF 10, 20, 30 or 40? And what SPF should I be aiming for?
Step away from the mixing bowl, friend. Mixing sunscreens is a no-no. But it's important to understand why. First, let's get one thing out of the way: What the heck even is SPF?
According to Shari Lipner, dermatologist at Weill Cornell Medicine and NewYork-Presbyterian, your sunscreen's SPF (sun protection factor) does indeed tell you how much sun protection it can offer you. Researchers test sunscreen on bits of skin, comparing it with totally unprotected skin as they're both exposed to sunlight. SPF is a measurement of how much ultraviolet radiation — short, invisible wavelengths of light from the sun — is necessary to burn the sunscreened skin as compared with the unadorned flesh.
The numbers themselves refer to how long you can bake in the sun without burning: If it takes 20 minutes for your bare skin to start reddening, using an SPF 15 sunscreen is meant to let you have fun in the sun for 15 times longer – about five hours. But you still need to reapply it every two hours because of sweating and all that, so don't actually pay

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Rank: 15
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Retrieved Text: A smiling sun painted in sunscreen, shown under normal and UV light. The message clear, good sunscreen is effective.
Children’s skin is a little more vulnerable and getting them coated with sunscreen can be a task, amidst an excited arrival at a pool, the beach, or the park. Those points apart, the principles for children and adults are similar.
Over 85% of the UK population appreciate that sun awareness messages apply to them. Even so, a survey by the British Association of Dermatologists suggests contradictory behaviour.
One in three people have been sunburnt during the last year, rising to about half of those who ventured overseas. Whilst achieving a lasting, even tan is best achieved without sunburn, this is often seen as “part of getting a tan”.
Sunbathers are more likely to use sunscreen than a few years ago, although a proportion make changes as part of tan management. Following the belief they should reduce use, or protection factor levels as they tan, to achieve a darker colour.
Ultraviolet A (UVA) – A factor in skin ageing, pigmentation problems and skin cancer, quite separate from tanning.
Ultraviolet B (UVB) – The rays which burn your skin and can again cause damage, including types of skin cancer.
An SPF factor on sunscreen indicates protection levels from UVB. SPF 15 will allow one fifteenth of UVB rays through, SPF 30 one thirtieth, SPF 50 one fiftieth. The difference between letting 7% and 2% through may seem small but matters over time.
There are however limits on how far claims will help. In some countries, you will

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Rank: 16
Score: 62.892113
Retrieved Text: When it comes to baby’s sensitive skin, you don’t want to mess around—if you’re planning on spending any time outdoors without plenty of shade, then you know sunscreen is a must. Every baby needs her tender skin protected, but as parents we worry about the chemicals we’re putting on our babies’ bodies. Luckily, there is lots of information out there about which types of sunscreen are safest for babies.
Which Types of Sunscreens Are Safest for Babies?
Experts recommend broad spectrum sunscreens between SPF 15 and 50 for babies. Broad spectrum just means that it provides protection from both UVA and UVB rays. You want to make sure there is enough protection, but you also don’t want to get complacent because your sunscreen has such a high SPF that you don’t bother to reapply. Additionally, experts say that creams or lotions are the best formulas for babies. A cream ensures a more even application, and you don’t have to worry about your baby accidentally inhaling the chemicals from a spray formula. Finally, when it comes to ingredients, natural is better—it’s safer to err on the side of avoiding ingredients such as oxybenzone and octisalate in favor of natural UV blockers such as zinc oxide and titanium dioxide.
How Should I Apply Sunscreen to My Baby?
Experts recommend not using sunscreen on babies under six months. Instead, keep their skin covered with long sleeves and pants, hats, etc.
For babies over six months, if you’re applying a new sunscreen to your baby for the first time, test a small patch of skin

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Rank: 17
Score: 62.67743
Retrieved Text: Home » Survey asks: Are you using sunscreen correctly?
Survey asks: Are you using sunscreen correctly?
Schaumburg, IL – Many people don’t understand the information on sunscreen labels or use the product correctly, potentially raising their risk for skin cancer, according to the results of a survey conducted by the American Academy of Dermatology.
More than 1,000 people filled out the academy’s online survey about sunscreen. The results: 68 percent of respondents incorrectly believe sunscreen with a Sun Protection Factor of 30 provides double the protection of an SPF 15 sunscreen, and 55 percent believe a higher-SPF sunscreen protects longer than a lower-SPF sunscreen.
A sunscreen with a higher SPF can block “slightly more” rays than a lower-SPF sunscreen, but users must still reapply the product, AAD president and dermatologist Abel Torres said in a press release. The association also pointed to a recent study from Johns Hopkins University School of Medicine that suggests people who rely only on sunscreen for sun protection may not be applying enough.
For that study, researchers studied 758 people with a history of non-melanoma skin cancer and 34,161 people with no history of cancer. They found that people with non-melanoma skin cancer still developed sunburns as frequently as those without the disease even though cancer patients were more likely to put on sunscreen, move to shade and don protective clothing (pants, long-sleeved shirt, wide-brimmed hat and sunglasses). The protective clothing and shaded areas lowered the risk of sunburn – using sunscreen did not, researchers concluded. AAD recommends using at least 1 ounce of sunscreen (enough

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Rank: 18
Score: 62.652977
Retrieved Text: Just when I was about to spend the time breaking down what this all means on sunscreen and how to use it, I found this gem of an article written by the lovely, Tricia Trimble. Tricia is the founder of the beautiful, holistic Suntegrity Skincare line I have been using and selling for years now. I figure why “reinvent the wheel” when she has done the work of clarifying all you need to know to understand and use your SPF correctly to prevent burns and damage. I’m not sure if you know her story but her mom passed away from skin cancer which is why Tricia went on to “create lemonade out of lemons” as she told me when we met! Her passion for creating a healthy sunscreen to not only prevent sunburns but also cancer and damage to our environment and ecosystem is contagious and inspiring! She is a lovely human doing good things.
Did you know that up to 90 percent of visible skin aging is caused by sun damage? Or that one in five people get some form of skin cancer in their lifetime? If you want to keep your skin youthful and protect yourself from skin cancer, doesn’t it make logical sense to wear sunscreen?
Well, yes, but then… did you know that recent studies indicate many sunscreens can cause endocrine disruption and harm the wildlife in our ocean? And on top of that, approximately 95 percent of people are vitamin D deficient and being in the sun is what your body needs to

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Rank: 19
Score: 62.464874
Retrieved Text: If you love the sunny outdoors, you might ask yourself, “What SPF sunscreen should you use to exercise outside?” While it might seem like you need a PhD in sunscreen technology just to understand the label, it doesn’t have to be that way, especially when you use bu products. We’ve brought things back to basics without compromising the health and safety of your skin.
Non-melanoma skin cancer is one of the most common cancers in America and Australia. Millions of cases are reported every year, and millions more go undiagnosed. Some dermatologists consider this form of cancer to be an under-recognized epidemic that could be prevented. The easiest way to do this is to stay out of the sun, especially during the hottest times of the day. An alternative to this is to wear protective UV clothing. If that is not possible, or you want something in between, sunscreen is the best option. Choosing the right kind can block dangerous UVA and UVB rays and slow down the aging effects of the sun. The right level of protection is key; so, when it comes to wanting to know what SPF sunscreen should you use to exercise outside, we’ll tell you more is better.
When you see sunscreen for sale, you may notice an SPF rating ranging from 10 to 70 or more. How much does a 30 SPF offer over a 15 SPF? If you think it’s twice as much, you’re wrong. In fact, a 15 SPF protects 93% of the sun’s rays and a 30 SPF protects

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Rank: 20
Score: 62.17324
Retrieved Text: Summer is a dangerous time when it comes to being outside so much and, of course, the never ending lust for tanned skin. It makes me very worried and even sick sometimes when I see people lying on the beach for hours without any sunscreen on when in most cases they are already super tanned. I believe in SPF for both face and body and I would rather walk with my legs looking very pale rather than aging sooner that I would want to.
Please don‘t try to tell me off by saying that sun provides vitamin D and we need that. I agree 100% and we get that vitamin D as there isn‘t a suncreen that we can buy, which would protect you from the sun completely. Bear in mind that SPF 15 product blocks about 94% of UVB rays, an SPF 30 product blocks 97% of UVB rays; and an SPF 45 product blocks about 98% of rays (took this info from Tamira Jarrel‘s blog, she wrote an amazing post about sunscreen!). Therefore, you do get some sunhine to your skin either you want it or not, and I believe that it is enough. As I mentioned before, I don‘t want to get wrinkles as late as possible, I don‘t want skin cancer and I don‘t want any sun burns or more visible hyperpigmentation (yes, sun influences that and makes them appear darker). If you want the same things for your skin, I have two products to tell you about that will be helping me

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Rank: 21
Score: 61.32715
Retrieved Text: This branded SPF 30 sunscreen sprayer includes ground shipping.
The SPF 30 Sunscreen Pen Sprayer is a portable sunscreen sprayer that can be branded with your very own custom-designed label. Perfect to giveaway at summertime marketing events and outdoor exhibitions. Available in eight vibrant colors, this SPF 30 sunscreen spray features a convenient pocket clip. The sunscreen is an FDA approved broad spectrum formula that protects against both UVA and UVB rays, reducing the risk of sunburn, skin cancer and premature skin aging. Full-color label printing is included in our price. Free ground shipping.
Available ColorsFrosted Cap: Blue, Green, Orange, Red, Purple, Pink, Clear or Black.
Free SetupPrice includes 4-color process printing on a white label.

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Rank: 22
Score: 61.28497
Retrieved Text: Over the past three decades, more people have been diagnosed with skin cancer than all other cancers combined. Today, one in five Americans will develop skin cancer in the course of his or her lifetime. This is an alarming fact, considering what little we actually know about sun safety and how our protection from the sun is inherently flawed. Here are some important sun safety tips about what you can do to protect your skin and even safe your life.
As consumers, we trust sunscreen products far too easily, doing little to assess what the numbers after the "SPF" sign mean or caring to look at the ingredients list at the back of the package. The math isn&apos;t adding up in the way you might think, and the chemicals used to make sunscreen aren&apos;t exactly the purest of the bunch.
Skin cancer is the most common form of cancer in the U.S., afflicting more than 2 million people per year. This means there are more new cases of skin cancer than the combined incident of breast, prostate, lung and colon cancers. Between 1992 and 2006, the treatment of non-melanoma skin cancers rose by nearly 77 percent. Meanwhile, half of all adults report at least one sunburn in the past 12 months.
Theoretically speaking, using a SPF 100 sunscreen would offer you twice the protection of SPF 50 sunscreen, or so most consumers believe. However, this is not the case. Values greater than 50 offer negligible extra protection. SPF 50 sunscreen can shield your skin from 98 percent of sunburn

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Rank: 23
Score: 61.21977
Retrieved Text: Dr. Anatoli Freiman is chair of the Canadian Dermatology Association Sun Protection Program and shares his expertise in the Toronto Star this week discussing sunscreens. Click here to read the article!
Everyone knows sunscreen protects against sunburn and skin cancer, but choosing the right product can be confusing. It’s important that a sunscreen is labelled “broad spectrum,” meaning it protects against both ultraviolet A and B rays. Both types contribute to the development of skin cancer.
Sun Protection Factor (SPF) relates only to the sunscreen’s power against UVB. Dermatologists generally recommend a sunscreen with SPF 30 or higher. Whether the sunscreen is a cream, lotion or spray doesn’t matter as along as it’s applied appropriately. That means using at least 30 mL, about an ounce (shot glass size), to cover the body. Apply 15 minutes before sun exposure and repeat every two hours, or more frequently if you’re sweating or swimming. Many moisturizers and makeup foundations now contain sunscreen. While they are better than nothing, they usually have only an SPF 15, which is not sufficient. And don’t forget to use a lip balm with sun protection. We’re seeing a lot of patients with sun-damaged lips.
← Skin cancer risk at 1 in 5!

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Rank: 24
Score: 61.195457
Retrieved Text: The NIVEA Men Energy Broad Spectrum SPF 15 Sunscreen is a lotion that revitalizes and energizes the skin.
It can be used every day as a screen against the ravaging impact of the sun.
It’s a broad spectrum lotion that will protect the skin from both UVA and UVB rays. The biggest plus to this lotion is the energizing nature with the addition of Q10.
The company began making skin cream in 1911. It came in a small, metal tin even from the beginning. It started as an emulsifier lotion that combined oil and water into a mixture that would moisturize skin.
The creator of the cream was Dr. Isaac Lifschutz, but it was a dermatologist professor named Paul Gerson Unna who saw the possibilities.
He brought the new emulsifier to a chemist, and they started a company. They named the cream NIVEA based on the Latin word for snow.
CoEnzyme Q10 is an antioxidant that occurs naturally in the body. It protects cells from damage. Throughout your lifetime, the level of Q10 will rise and fall.
It rises towards its peak at ages 20 to 30, but then it will decline as you age beyond 30. In the skin, Q10 prevents damage and helps produce collagen.
Collagen is what gives skin its elasticity in your youth. Elasticity is the firmness that will fade as you age.
CoEnzyme Q10 stimulates the production of collagen, which leads to less wrinkles and helps avoid skin that looks like leather.
When you need to replace Q10, it makes sense to use a lotion that has the ability to stimulate

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Rank: 25
Score: 61.125263
Retrieved Text: Whether you’re lathering on sunscreen before you head to the pool, or covering up for general protection while going about your daily routine, it’s good to know what an SPF actually does.
SPF stands for “Sun Protection Factor,” and it does exactly that: protects you from the sun! While clothing is the most basic and generally the best means of sun protection, a lot of clothing is made with a loose weave which allows the UV rays to pass through, so it’s always prudent to use a suncreen.
There are different levels of SPFs. When you’re buying a sunscreen and the bottle says “SPF 15,” the number 15 stands for the amount of protection that sunscreen is going to give you.
See the difference in the SPF versus the different protection percentages? An SPF 30 is only giving you four percent more protection than the SPF 15.
Exposing your skin to the sun for just 10 minutes can produce burning and skin cell damage. Exposing yours skin to the sun with an SPF 15 will allow you to be in the sun for around 150 minutes without experiencing skin cell damage.
Be aware that applying sunscreen isn’t a one-time thing. SPF should be reapplied every two hours, and even more frequently if you are swimming or perspiring due to hot weather or increased activity.
Another way to to look at SPF levels is to observe the number of photons that enter your skin —a photon being a particle that represents radiation.
SPF should be used every day, even when the sun isn’t shining

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Rank: 26
Score: 61.003597
Retrieved Text: Each day, more people learn about the importance of wearing sunscreen whenever they’re outdoors to shield themselves against the sun’s harmful UV (ultraviolet) rays. While that news is heartening, getting that information out is only half of the battle.
If a user misunderstands how a sunscreen’s Sun Protection Factor (SPF) works, or if the product is incorrectly applied, the level of protection received can be considerably lower than he or she believes it to be. That can be very dangerous.
If your mouthwash contained a lesser percentage of cinnamon flavor than you thought it did, it would make absolutely no difference as far as your health is concerned. However, if you walked around every day thinking you were wearing a sunscreen that provided more skin defense than it actually did, that mistaken notion could end up resulting in skin cancer. Or, even worse, the potentially deadly melanoma.
We’d like to help clear up this confusion. There is a view held by many that, because an SPF 50 sunscreen absorbs 98% of UVB radiation while an SPF 100 sunscreen absorbs 99%, just 1% more, the SPF 100 sunscreen offers hardly any advantage over the SPF 50 sunscreen. That’s a misinterpretation of the facts.
If an SPF 100 sunscreen is correctly applied and continually re-applied every two hours at a minimum, (or immediately after swimming or profuse sweating) it’ll provide adequate skin protection for double the amount of time that a SPF 50 sunscreen will.
There are other ways that we inadvertently end up leaving ourselves vulnerable to those dangerous UV rays. We’ll

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Rank: 27
Score: 60.94188
Retrieved Text: Love your sun-kissed glow? Watch out: with more than 90% of visible skin aging caused by the sun, today’s tan could be tomorrow’s wrinkles. That’s why sunscreen is not just for the beach – it's an important part of every savvy girl’s daily beauty and skincare routine.
So how can you be sure you're protected do you ask? We turned to celebrity dermatologist Dr. Gervaise Gerstner to steal her secrets for healthy, youthful skin – and debunk five of the most common myths about sunscreen and premature aging.
Myth #1: "Sunscreen smells bad and feels tacky on my skin; I only need to wear it at the beach."
Myth #2: "My skin is naturally dark so I don't need to wear sunscreen."
“People of all skin types get skin cancer,” warns Dr. Gervaise Gerstner. The truth behind this myth is that melanomas - the most dangerous form of skin cancer - are much rarer in African Americans, Latinos and Asians. But these ethnicities are also likely to be diagnosed with later stage and more aggressive melanomas than their fair-skinned counterparts. That's why skimping on sun protection can cost you, no matter your skin tone. In fact, between 1970 and 2009, melanomas increased eightfold among young women aged 18 to 39, reports the Mayo Clinic. Fight back against these scary stats by wearing a broad spectrum sunscreen every day.
Myth #3: "SPF level is what protects me from the sun."
Don't be fooled by sub-par sunscreens with a high SPF number. There are two types of damaging rays and SPF only protects against

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Rank: 28
Score: 60.933777
Retrieved Text: Avene Lait SPF 50+ 100 ml Sun Lotion SPF 50+ for very fair skin. Helps to prevent photodermatosis. ..
Body make-up to cover skin imperfections & discolorations. Protects and reduces spider veins. Suitab..
High Sun Protection with SPF50 A high sun protection for the face and body, suitable for sensitive,..
Sunscreen lotion and body to spray, water-resistant.Ideal for skins with increased oiliness and acne..
Frezyderm Sun Screen SPF30 Mousse Face & Body Foam 200ml..
Sunscreen lotion and body, water-resistant. Contains only natural filters and is ideal for sensitiv..
Sunscreen lotion Sunscreen Velvet Body Lotion with high sunscreen spf 50, for all skin types. Idea..
Sunscreen lotion and body, with free-flowing texture, resistant to perspiration.Ideal for those who ..

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Rank: 29
Score: 60.75226
Retrieved Text: Always 100% chemical-free actives, Sunforgettable® Total Protection™ Body Shield SPF 50 goes beyond SPF to provide all-mineral, totally invisible daily defense from harmful environmental aggressors.
A powerful antioxidant that helps prevent skin aging due to pollution and other environmental aggressors.
Lipochroman® is a registered trademark of Lipotec, S.A.
Physavie® is a registered trademark of Chemyunion.
UVB exposure causes redness or burning, while UVA exposure causes skin darkening/pigmentation. Protection from both UVA and UVB means this product provides Broad Spectrum protection. Total Protection™ Body Shield SPF 50 provides Broad Spectrum SPF 50 (UVB protection) and PA+++ (UVA protection).
Total Protection™ Body Shield SPF 50 has a PA+++ rating.
We measure our pollution protection by directly measuring free radicals created from UV + pollution events on unprotected skin and skin protected with Sunforgettable® Total Protection™ Body Shield SPF 50. We use a testing technique called electron spin resonance (ESR) that uses a combination of a magnetic field and electron magnetic waves to directly detect the unpaired electrons of free radicals.
Is Total Protection™ Body Shield SPF 50 non-comedogenic?
Yes, Sunforgettable® Total Protection™ Body Shield SPF 50 is non-comedogenic.
Is Total Protection™ Body Shield SPF 50 hypoallergenic?
Yes, Sunforgettable® Total Protection™ Body Shield SPF 50 is hypoallergenic and dermatologist-recommended.
Is Total Protection™ Body Shield SPF 50 gluten free?
Yes, Sunforgettable® Total Protection™ Body Shield SPF 50 is gluten free. People who have gluten allergies may experience sensitivity when using topical products. Total Protection™ Body Shield SPF 50 is gluten free, and therefore, safe for those with Celiac disease. In addition, all Colorescience® products are 100% free from parabens, phthalates, synthetic fragrance,

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======= Instance Index 1234 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are SPF 30 or SPF 100 ):

A sunscreen with a higher SPF value protects the skin longer.


Allie looks for sunscreen at the store. She sees SPF 30 and SPF 100. Which likely protects her skin better SPF 30 or SPF 100?

Target Text: SPF 100

#### Retrieved Documents ####

Rank: 0
Score: 71.6241
Retrieved Text: Sunscreen 101 — What Do SPF Numbers Mean?
In the past, you may have been told that SPF numbers were relatively simple to understand. If you can be out in the sun for 10 minutes with unprotected skin before your skin would begin to burn, the explanation went, then with an SPF 15, you could stay in the sun 15 times as long, or 150 minutes before you would burn. Simple, right? Not so fast, the science behind SPF is actually quite detailed, and sunscreens should be reapplied every 2 hours, regardless of the SPF.
1. Look for Broad Spectrum coverage. While we generally apply sunscreen in the summer to avoid a sunburn, UVA rays are present year-round, and those are the rays that have an aging effect on the skin. To keep your skin looking its best, as well as avoiding an increased risk of skin cancer, you want protection from UVA rays and UVB rays which is what Broad Spectrum protection offers.
2. Go for SPF 30 to 50. Even if you had SPF 100, it wouldn't protect you from 100% of the sun's rays, so looking for that sort of protection is not necessary. SPF 15 protects you from slightly more than 93% of the sun's UVB rays. SPF 30, even though it LOOKS like it offers double the protection of SPF 15, protects you from nearly 97% of the UVB rays. As the SPF goes up, the percentage of protection increases only slightly--when you jump up to SPF 50, the increase in protection is even

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Rank: 1
Score: 69.238716
Retrieved Text: Now that Summer is in full swing, it’s especially important to keep your skin protected from the sun’s UVA/UVB rays, which can cause premature skin aging, skin cancer, sun spots, and more!
With so many chemical ridden sunscreen formulas on the market, it can be overwhelming to choose the one that you think will be right for you. And if you’re still confused about the difference between chemical and physical formulas, check out our blog post that breaks down the difference! In short, physical formulas are most gentle on your skin because they lack common chemical irritants that can cause skin inflammation and even disturb oceanic ecosystems.
This week, we’ve partnered with DIY Beauty Expert, Alexandra Potora to make her own all-natural, and 100% non-toxic physical sunscreen using our wholesome ingredients and tried and true recipe!
Follow Alexandra on Instagram and subscribe to her YouTube Channel for more DIY beauty videos!
Watch the tutorial below or print out the recipe to follow along!
Mango Butter: Moisturizes and keeps your skin soft.
Zinc Oxide: protects naturally against UVA and UVB -- 2 tablespoons for SPF 15 protection. Protects against 93% of UVB rays.
SPF 30 protects against 97% of UVB rays, whereas SPF 15 protects against 93% of UVB rays. It is commonly known that if applied frequently there isn't much of a difference between SPF 15 and 30.
1.Melt the Mango Butter, the Oil using the double boiler method and stir.
2. Remove from the heat when all ingredients have melted.
3. Slowly add the Zinc Oxide and continue stirring.
4. Store in a cool place.
This formula

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Rank: 2
Score: 68.97932
Retrieved Text: He says protecting your body from the sun is a whole package deal. But the FDA says there's no evidence such products provide better protection against harmful rays-and they may actually make us feel overconfident and less likely to reapply.
Still have last year's bottle of sunscreen? But only to the level of an SPF 4, which gives you protection for about 45 minutes.
One of the issues of disagreement is that even though the FDA contends that products labeled with SPF higher than 50 are "inherently misleading", they have not mandated that producers of sunscreen refrain from labeling their product with values above this. "But this is probably my biggest beef with the sunscreen industry", Lunder tells Fast Company.
Apply sunscreen 30 minutes before going outside. Because there is no justified reason to use products with a higher SPF, then using said products only puts the person in an unnecessary degree of risk.
An estimated 5.6 million Americans will confront skin cancer in 2017.
The Food and Drug Administration has yet to decide whether it will stop allowing sunscreen manufacturers to market their products with SPF numbers higher than 50, even though sunscreens with 90 and 100 SPF coverage often offer similar protection as those that are SPF 50, Lunder said.
"This year, we estimate that almost every sunscreen we reviewed passes the FDA test", the EWG researchers write, "but that about half of them would not offer enough UVA protection to be sold in Europe".
Over the past three decades, more people have had skin cancer than all other cancers combined.

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Rank: 3
Score: 67.78058
Retrieved Text: When you’re faced with lots of sunscreen options, it’s easy to be overwhelmed by all the different types and brands. But the first thing that really matters is the SPF.
Let’s talk about what is the minimum SPF you should be reaching for next time you buy sunscreen.
When looking at a sunscreen bottle, we know a high SPF is good, but maybe not why it’s good. By understanding what SPF measures, we can decide how much is right for us.
SPF is an acronym for Sun Protection Factor, a measurement of how long it takes someone to burn with and without the sunscreen. This is learned by applying the product on a participant and comparing the length of time it takes protected and unprotected skin to burn under a UV lamp.
An SPF of 10, for example, means that it took participants in that sunscreen’s tests 10 times longer to burn while wearing it and thus protects from 90% of sunburn-causing UVB rays.
Obviously, the higher the SPF, the longer you could theoretically go without burning and the more protection you are getting from damaging UV rays.
So what SPF is enough?
The FDA seems to think that SPF 15 is required according to its sunscreen regulations, but most dermatologists and skin cancer specialists conclude that SPF 30 is the minimum to truly protect against damage. Those with lighter skin tones are advised to wear higher SPF sunscreen and to wear it and reapply it more often.
Another thing to consider is whether or not the sunscreen is broad spectrum. This is where

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Rank: 4
Score: 67.16146
Retrieved Text: What SPF sunblock should you buy, SPF 15, 30, 60 or greater?
Use of Sunblock creams or sunscreens is now popular amongst both male and female sexes. When you go to a dermatologist or cosmetician to have an opinion about better skin care management, they will tell you to use a sunblock whenever you go out in the sun. When you go to a shop to buy a sunscreen, you don’t know what SPF sunblock should you buy?. You fear that an SPF 15 sunblock is nothing in front of SPF 50 or 90 sunblock, then you also worry about the cost of a high SPF sunblock.
Sun rays contain ultraviolet radiations that have the tendency to damage your skin. Our skin has the ability to resist this damage for a few minutes to an hour depending upon the colour of the skin. Dark coloured individuals tend to withstand the sunlight for a longer period of time as compared to a fair coloured individual. White skinned individuals more commonly complain of sun damage, rash, pimples and acne as compared to dark skinned individuals.
Why do the dark colored individuals withstand sunlight better?
Cosmetologist encourages the use of sunblock in adults when they go out in the sun. When you buy a sunscreen or sunblock cream, you see a special value on the pack represented by SPF. You may see various values of SPF, maybe 15, 24, 30, 40, 45, 60 etc. SPF stands for sun protection factor. The higher the value better will be the protection. For instance, a 15

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Rank: 5
Score: 66.22304
Retrieved Text: When it comes to the SPF number on our sunscreen bottles, most people shrug and grab the highest one, figuring bigger is better.
SPF 30? 50? 75? Bring it on—it will work, right?
There's actually much more to it than that, and it's all rather scientific. Simply put, SPF, or Sun Protection Factor, is a measure of how well a sunscreen will protect your skin from UVB rays.
Two kinds of UV radiation—UVA and UVB—can damage the skin. UVB rays are usually the culprit behind those pink, peeling sunburns, but UVA rays can be just as problematic. We have UVA rays to thank for wrinkles and leathery, saggy skin.
Wearing sunscreen with an SPF rating gives you a certain amount more time of safe sun exposure. It's fairly simple to calculate how long you can stay in the sun safely, as long as you know the SPF number and how long it takes you to develop a sunburn normally.
To calculate the safety of your sunscreen, multiply the number of minutes you can sit outside without burning by the SPF number. For example, if you would normally burn after 10 minutes in the sun, applying sunscreen with an SPF rating of 15 would allow you to stay in the sun safely for about 150 minutes. Of course, this is a rough estimate, and it really depends on your skin type, the amount of sunscreen you use, and the intensity of the sunlight you’re in.
Interestingly, the SPF scale is not linear. Contrary to what you might think, upgrading from SPF 15 to

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Rank: 6
Score: 65.61924
Retrieved Text: Q: What exactly are UV rays?
Exposure to UV radiation is a major factor in most skin cancers, and most UV radiation comes from the sun! You are also exposed to UV rays in tanning beds.
UVA rays age skin cells. They're linked to skin damage like wrinkles, but can also cause skin cancers (especially from tanning beds, which produce a lot of UVA rays and have been linked to skin cancer).
UVB rays are the main rays that cause sunburns and are believed to cause most skin cancers.
Avoid the sun between 10 a.m. and 4 p.m. UV rays are strongest between these times. Wear sunblock and cover your skin even if you're skitting in the shade or it's cloudy -- UV rays can reflect off of many surfaces and can sometimes be amplified by cloud cover. Staying in the shade and cloudy days mean you'll be less exposed to UV rays, but using sunblock is your best bet when it comes to protecting your skin.
The American Cancer Society suggests broad spectrum (this means it protects against UVA AND UVB rays), water-resistant sunblock that has not expired.
Sunscreen labeled with SPFs as high as 100+ are available. Higher numbers do mean more protection, but many people don’t understand the SPF scale. SPF 15 sunscreens filter out about 93% of UVB rays, which SPF 30 sunscreens filter out about 97% , SPF 50 sunscreen about 98%, and SPF 100 about 99%. The higher you go, the smaller the difference becomes. No sunscreen protects you completely. Sunscreen with an SPF lower than

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Rank: 7
Score: 65.42733
Retrieved Text: LOS ANGELES Gia Alexi-Tomari wants to look her best and wonders whether her age is starting to show.
"I worry quite a bit about wrinkles and getting older," said Gia.
She uses a sunscreen that says it has special anti-aging ingredients. Gia says she sees a visible difference.
"The skin tone is much smoother and the texture is a lot firmer," said Gia.
Sunscreens by nature have anti-aging effects because they block damaging /*UV rays*/. But now, new products are promising even more and acting more like high-end skin care. They've added ingredients like retinol, peptides and plant extracts to fight wrinkles and stimulate collagen production.
"We're talking about adding a primarily antioxidant, or a skin protein maybe from a fetal skin cell, added to the sunblock, which also counteracts free radical formation, which also causes aging," said dermatologist Dr. Dina Anderson.
It's the free radical formation that causes wrinkles, loss of skin firmness and an uneven skin tone.
Dr. Anderson says studies show some of the ingredients may live up to the claims, but before you pay for new protection, you should look for some scientific backing instead of just a commercial claim.
"You might want to do some investigating on the Internet into some of the research that has been done," said Dr. Anderson.
Even then, you have to be careful about what you cover and how often.
"You need to reapply them every two-to-three hours," said Dr. Anderson. "Even more frequently if you're going to be in the water."
Gia puts on her sunscreen first thing in the morning, and then reapplies a couple

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Rank: 8
Score: 65.03864
Retrieved Text: For babies 6 months and older, or anyone in search of an ultra-gentle, fragrance-free mineral SPF stick.
Your little one's skin needs extra TLC. Our Mineral Baby SPF 50 Unscented Moisturizer is our purest lotion sunscreen, designed to safeguard the most precious and delicate skin.
People who love both makeup and great sun protection, and want to reapply SPF without it messing up their makeup, this is what you've been waiting for!
Protect your pucker with our Liplux® SPF 30 balm. This vitamin-enriched, antioxidant formula protects and conditions lips with a Peppermint Vanilla flavor.
Like FaceTune in a bottle, our Classic SPF 30 Dawn Patrol Makeup Primer helps your complexion look softer, smoother, and brighter—with or without makeup.
For anyone with dry, sunburned or just plain thirsty skin morning, noon and night.
Everyone needs a good A.M. moisturizer with sunscreen!
Mineral SPF shouldn't ghost you—this one nourishes and protects without leaving any white residue on your skin. SPF 30 moisturizing mineral sunscreen with antioxidant benefits.
This all-in-one lip treatment moisturizes and protects with broad spectrum UVA/UVB SPF 30 protection. This product is unscented, but you’ll still want to say MUAH!
Travelers or anyone who wants mini sizes of our mighty sun products. A pouch with four essential TSA-friendly size products inside!
Sun's out, fun's out! Our spray-on sunscreen is sheer with good-for-your-skin ingredients, plus it's organic SPF 30 and the perfect petite size to take with you.
Organic fans who love the outdoors! This is a broad-spectrum, SPF 50 moisturizing lotion sunscreen with antioxidants for enhanced UV protection.
Sun's out, fun's out! A sport sunscreen doesn't have to

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Rank: 9
Score: 64.934166
Retrieved Text: Steps Every Man Needs to Follow When Applying Sunscreen.
Using sunscreen might not be as simple as you think: Most people hold inaccurate beliefs about their sunblock, new research from the American Academy of Dermatology (AAD) suggests.
And these misconceptions might leave you at greater risk of developing skin cancer.
In the survey, only 32 percent of respondents knew that an SPF 30 sunscreen does not provide twice as much protection as an SPF 15 sunscreen does.
In fact, the increase in protection from an SPF 15 to an SPF 30 isn’t very significant.
An SPF 30 blocks 97 percent of sunburn-causing UVB rays, while an SPF 15 blocks 93 percent, says Josh Zeichner, M.D., a spokesman for the AAD.
That means an SPF 30 blocks only 4 percent more UVB rays than SPF 15 does, a far cry from the “double” the numbers behind them would have you believe.
What’s more, just under half of those surveyed knew that a higher SPF sunscreen doesn’t protect you from the sun for a longer time than a lower SPF one does.
The real deal: Any sunscreen, no matter the SPF, wears off after two hours.
Putting too much faith in high SPF—whether it’s for amount of protection or how long you can safely stay in the sun—can be dangerous, since it can lead to a false sense of security regarding your burn risk, says Dr. Zeichner.
That may mean you might be more likely to stay in the sun for longer than you should or put off reapplying more sunscreen, which can make you more likely to

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Rank: 10
Score: 64.83145
Retrieved Text: Easy sun protection tips with your loved ones this summer.
A video that shows exactly why we need to wear sunscreen.
“Yeah it is,” I agreed.
Just as an FYI, you should know that this post is sponsored by Nivea. But all opinions expressed by the author are 100% authentic and written in their own words.
As a child I roamed the NSW countryside with, maybe, one coat of SPF15. We never reapplied it and I now have arms covered in freckles and an aging face of pale skin as a constant reminder of my childhood.
In recent years we’ve been told to use sunscreen to protect ourselves from the harsh Australian sun, but do we really understand why? It wasn’t until I watched this video that I really understood it.
Filmed here in Australia, this clip shows exactly why we need to wear sunscreen – because the sun sees our skin differently when we apply it. Once you’ve seen the clip (I dare you not to watch it at least five times, it’s so fascinating) you truly can see how the sunscreen we use acts as a barrier helping to protect our skin from damage.
As someone with pale skin I’m constantly keeping up with skin care and sunscreen recommendations. I’m also constantly informing my friends and family about the difference between SPF 50 and SPF 30. The SPF (Sun Protection Factor) has absolutely nothing to do with strength but rather the amount of time you are protected.
Say you have pale skin like I do and you start to burn within three

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Rank: 11
Score: 64.47896
Retrieved Text: If you love the sunny outdoors, you might ask yourself, “What SPF sunscreen should you use to exercise outside?” While it might seem like you need a PhD in sunscreen technology just to understand the label, it doesn’t have to be that way, especially when you use bu products. We’ve brought things back to basics without compromising the health and safety of your skin.
Non-melanoma skin cancer is one of the most common cancers in America and Australia. Millions of cases are reported every year, and millions more go undiagnosed. Some dermatologists consider this form of cancer to be an under-recognized epidemic that could be prevented. The easiest way to do this is to stay out of the sun, especially during the hottest times of the day. An alternative to this is to wear protective UV clothing. If that is not possible, or you want something in between, sunscreen is the best option. Choosing the right kind can block dangerous UVA and UVB rays and slow down the aging effects of the sun. The right level of protection is key; so, when it comes to wanting to know what SPF sunscreen should you use to exercise outside, we’ll tell you more is better.
When you see sunscreen for sale, you may notice an SPF rating ranging from 10 to 70 or more. How much does a 30 SPF offer over a 15 SPF? If you think it’s twice as much, you’re wrong. In fact, a 15 SPF protects 93% of the sun’s rays and a 30 SPF protects

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Rank: 12
Score: 64.407616
Retrieved Text: this product provides the safest and easiest way to defend skin against uva, uvb and infrared rays while protecting delicate elastin protein from breaking down. it is gentle enough for acneic skin and even retinol users.
SheerZinc SPF 30 is a sunscreen that not only softens signs of aging but also has a restorative effect on your skin’s previous sun exposure. this 100% physical sunscreen is light enough to wear under makeup and harnesses the power of zinc oxide to guard and protect your skin; this mineral based sunscreen absorbs quickly, working to elegantly shelter your skin.
best for: SheerZinc SPF 30 is appropriate for all types of skin, however particularly effective for sensitized and acne prone skin.
apply to the face, neck, and décolleté as desired throughout the day.
SheerZinc SPF 30 protects both elastin and skin proteins from harmful uv damage and collagen breakdown. ensuring uva and uvb protection, while providing a translucent glow.
Stem Cell Rebuilding Complex addresses compromised, fragile or maturing skin by restoring crucial hydration, fortifying the epidermis and stimulating collagen production for increased firmness.
Solar Moisturizer SPF 30 offers a dual chemical spf and moisturizer protect elastin protein from uv damage while plumping peptides encourage more youthful looking skin.

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Rank: 13
Score: 64.06104
Retrieved Text: Summer is a dangerous time when it comes to being outside so much and, of course, the never ending lust for tanned skin. It makes me very worried and even sick sometimes when I see people lying on the beach for hours without any sunscreen on when in most cases they are already super tanned. I believe in SPF for both face and body and I would rather walk with my legs looking very pale rather than aging sooner that I would want to.
Please don‘t try to tell me off by saying that sun provides vitamin D and we need that. I agree 100% and we get that vitamin D as there isn‘t a suncreen that we can buy, which would protect you from the sun completely. Bear in mind that SPF 15 product blocks about 94% of UVB rays, an SPF 30 product blocks 97% of UVB rays; and an SPF 45 product blocks about 98% of rays (took this info from Tamira Jarrel‘s blog, she wrote an amazing post about sunscreen!). Therefore, you do get some sunhine to your skin either you want it or not, and I believe that it is enough. As I mentioned before, I don‘t want to get wrinkles as late as possible, I don‘t want skin cancer and I don‘t want any sun burns or more visible hyperpigmentation (yes, sun influences that and makes them appear darker). If you want the same things for your skin, I have two products to tell you about that will be helping me

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Rank: 14
Score: 63.898266
Retrieved Text: Dr. Anatoli Freiman is chair of the Canadian Dermatology Association Sun Protection Program and shares his expertise in the Toronto Star this week discussing sunscreens. Click here to read the article!
Everyone knows sunscreen protects against sunburn and skin cancer, but choosing the right product can be confusing. It’s important that a sunscreen is labelled “broad spectrum,” meaning it protects against both ultraviolet A and B rays. Both types contribute to the development of skin cancer.
Sun Protection Factor (SPF) relates only to the sunscreen’s power against UVB. Dermatologists generally recommend a sunscreen with SPF 30 or higher. Whether the sunscreen is a cream, lotion or spray doesn’t matter as along as it’s applied appropriately. That means using at least 30 mL, about an ounce (shot glass size), to cover the body. Apply 15 minutes before sun exposure and repeat every two hours, or more frequently if you’re sweating or swimming. Many moisturizers and makeup foundations now contain sunscreen. While they are better than nothing, they usually have only an SPF 15, which is not sufficient. And don’t forget to use a lip balm with sun protection. We’re seeing a lot of patients with sun-damaged lips.
← Skin cancer risk at 1 in 5!

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Rank: 15
Score: 63.752148
Retrieved Text: Is Makeup With Sunscreen Enough to Protect Your Skin?
Many foundations and powders contain sunscreen, but is it enough for daily protection?
You want to prevent wrinkles and skin cancer, so you are dedicated to wearing sunscreen. But coverage looks shiny or chalky, especially under makeup.
Many foundations and other makeup products offer a built-in sun protection factor (SPF). Is that your smartest beauty solution? Dermatologist Leslie Baumann, MD, says giving in to that temptation would be a mistake.
"Makeup does not provide enough coverage," she says. "You need seven times the normal amount of foundation and 14 times the normal amount of powder to get the sun protection factor on the label. No one does this."
So can you marry makeup and sunscreen in your routine and still look good? Yes, if you follow these steps.
1. Select the proper sunscreen.
Before you step in front of the bathroom mirror, find a sunscreen that offers enough protection. The Skin Cancer Foundation advises people to use a moisturizer containing broad-spectrum sunscreen (which means it blocks both UVA and UVB rays) with an SPF rating of at least 15. Ingredients such as zinc oxide, avobenzone (Parsol 1789) or ecamsule (Mexoryl), combined with octocrylene and avobenzone work best with makeup and provide broad spectrum sun protection.
Baumann says to layer a physical sunscreen, such as Aveeno Ultra-Calming Daily Moisturizer SPF 15, with a chemical sunscreen (either Topix Glycolix Elite Sunscreen SPF 30 or Blue Lizard Australian Sunscreen Sensitive Skin SPF 30), to block most of the sun’s rays.
Tina Turnbow, makeup artist, advises using a natural moisturizer,

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Rank: 16
Score: 63.64151
Retrieved Text: When it comes to baby’s sensitive skin, you don’t want to mess around—if you’re planning on spending any time outdoors without plenty of shade, then you know sunscreen is a must. Every baby needs her tender skin protected, but as parents we worry about the chemicals we’re putting on our babies’ bodies. Luckily, there is lots of information out there about which types of sunscreen are safest for babies.
Which Types of Sunscreens Are Safest for Babies?
Experts recommend broad spectrum sunscreens between SPF 15 and 50 for babies. Broad spectrum just means that it provides protection from both UVA and UVB rays. You want to make sure there is enough protection, but you also don’t want to get complacent because your sunscreen has such a high SPF that you don’t bother to reapply. Additionally, experts say that creams or lotions are the best formulas for babies. A cream ensures a more even application, and you don’t have to worry about your baby accidentally inhaling the chemicals from a spray formula. Finally, when it comes to ingredients, natural is better—it’s safer to err on the side of avoiding ingredients such as oxybenzone and octisalate in favor of natural UV blockers such as zinc oxide and titanium dioxide.
How Should I Apply Sunscreen to My Baby?
Experts recommend not using sunscreen on babies under six months. Instead, keep their skin covered with long sleeves and pants, hats, etc.
For babies over six months, if you’re applying a new sunscreen to your baby for the first time, test a small patch of skin

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Rank: 17
Score: 63.304256
Retrieved Text: Dear Science: What does sunscreen SPF mean, and what happens if you mix them?
Dear Science: I'm gearing up for a summer vacation, and I've been burned before — so I want to make the most of all these half bottles of sunscreen left in my cabinet. If you mix equal amounts of SPF 10 sunscreen and SPF 30 sunscreen, do you get SPF 10, 20, 30 or 40? And what SPF should I be aiming for?
Step away from the mixing bowl, friend. Mixing sunscreens is a no-no. But it's important to understand why. First, let's get one thing out of the way: What the heck even is SPF?
According to Shari Lipner, dermatologist at Weill Cornell Medicine and NewYork-Presbyterian, your sunscreen's SPF (sun protection factor) does indeed tell you how much sun protection it can offer you. Researchers test sunscreen on bits of skin, comparing it with totally unprotected skin as they're both exposed to sunlight. SPF is a measurement of how much ultraviolet radiation — short, invisible wavelengths of light from the sun — is necessary to burn the sunscreened skin as compared with the unadorned flesh.
The numbers themselves refer to how long you can bake in the sun without burning: If it takes 20 minutes for your bare skin to start reddening, using an SPF 15 sunscreen is meant to let you have fun in the sun for 15 times longer – about five hours. But you still need to reapply it every two hours because of sweating and all that, so don't actually pay

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Rank: 18
Score: 63.251774
Retrieved Text: Over the past three decades, more people have been diagnosed with skin cancer than all other cancers combined. Today, one in five Americans will develop skin cancer in the course of his or her lifetime. This is an alarming fact, considering what little we actually know about sun safety and how our protection from the sun is inherently flawed. Here are some important sun safety tips about what you can do to protect your skin and even safe your life.
As consumers, we trust sunscreen products far too easily, doing little to assess what the numbers after the "SPF" sign mean or caring to look at the ingredients list at the back of the package. The math isn&apos;t adding up in the way you might think, and the chemicals used to make sunscreen aren&apos;t exactly the purest of the bunch.
Skin cancer is the most common form of cancer in the U.S., afflicting more than 2 million people per year. This means there are more new cases of skin cancer than the combined incident of breast, prostate, lung and colon cancers. Between 1992 and 2006, the treatment of non-melanoma skin cancers rose by nearly 77 percent. Meanwhile, half of all adults report at least one sunburn in the past 12 months.
Theoretically speaking, using a SPF 100 sunscreen would offer you twice the protection of SPF 50 sunscreen, or so most consumers believe. However, this is not the case. Values greater than 50 offer negligible extra protection. SPF 50 sunscreen can shield your skin from 98 percent of sunburn

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Rank: 19
Score: 63.05112
Retrieved Text: A smiling sun painted in sunscreen, shown under normal and UV light. The message clear, good sunscreen is effective.
Children’s skin is a little more vulnerable and getting them coated with sunscreen can be a task, amidst an excited arrival at a pool, the beach, or the park. Those points apart, the principles for children and adults are similar.
Over 85% of the UK population appreciate that sun awareness messages apply to them. Even so, a survey by the British Association of Dermatologists suggests contradictory behaviour.
One in three people have been sunburnt during the last year, rising to about half of those who ventured overseas. Whilst achieving a lasting, even tan is best achieved without sunburn, this is often seen as “part of getting a tan”.
Sunbathers are more likely to use sunscreen than a few years ago, although a proportion make changes as part of tan management. Following the belief they should reduce use, or protection factor levels as they tan, to achieve a darker colour.
Ultraviolet A (UVA) – A factor in skin ageing, pigmentation problems and skin cancer, quite separate from tanning.
Ultraviolet B (UVB) – The rays which burn your skin and can again cause damage, including types of skin cancer.
An SPF factor on sunscreen indicates protection levels from UVB. SPF 15 will allow one fifteenth of UVB rays through, SPF 30 one thirtieth, SPF 50 one fiftieth. The difference between letting 7% and 2% through may seem small but matters over time.
There are however limits on how far claims will help. In some countries, you will

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Rank: 20
Score: 62.67743
Retrieved Text: Home » Survey asks: Are you using sunscreen correctly?
Survey asks: Are you using sunscreen correctly?
Schaumburg, IL – Many people don’t understand the information on sunscreen labels or use the product correctly, potentially raising their risk for skin cancer, according to the results of a survey conducted by the American Academy of Dermatology.
More than 1,000 people filled out the academy’s online survey about sunscreen. The results: 68 percent of respondents incorrectly believe sunscreen with a Sun Protection Factor of 30 provides double the protection of an SPF 15 sunscreen, and 55 percent believe a higher-SPF sunscreen protects longer than a lower-SPF sunscreen.
A sunscreen with a higher SPF can block “slightly more” rays than a lower-SPF sunscreen, but users must still reapply the product, AAD president and dermatologist Abel Torres said in a press release. The association also pointed to a recent study from Johns Hopkins University School of Medicine that suggests people who rely only on sunscreen for sun protection may not be applying enough.
For that study, researchers studied 758 people with a history of non-melanoma skin cancer and 34,161 people with no history of cancer. They found that people with non-melanoma skin cancer still developed sunburns as frequently as those without the disease even though cancer patients were more likely to put on sunscreen, move to shade and don protective clothing (pants, long-sleeved shirt, wide-brimmed hat and sunglasses). The protective clothing and shaded areas lowered the risk of sunburn – using sunscreen did not, researchers concluded. AAD recommends using at least 1 ounce of sunscreen (enough

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Rank: 21
Score: 62.652977
Retrieved Text: Just when I was about to spend the time breaking down what this all means on sunscreen and how to use it, I found this gem of an article written by the lovely, Tricia Trimble. Tricia is the founder of the beautiful, holistic Suntegrity Skincare line I have been using and selling for years now. I figure why “reinvent the wheel” when she has done the work of clarifying all you need to know to understand and use your SPF correctly to prevent burns and damage. I’m not sure if you know her story but her mom passed away from skin cancer which is why Tricia went on to “create lemonade out of lemons” as she told me when we met! Her passion for creating a healthy sunscreen to not only prevent sunburns but also cancer and damage to our environment and ecosystem is contagious and inspiring! She is a lovely human doing good things.
Did you know that up to 90 percent of visible skin aging is caused by sun damage? Or that one in five people get some form of skin cancer in their lifetime? If you want to keep your skin youthful and protect yourself from skin cancer, doesn’t it make logical sense to wear sunscreen?
Well, yes, but then… did you know that recent studies indicate many sunscreens can cause endocrine disruption and harm the wildlife in our ocean? And on top of that, approximately 95 percent of people are vitamin D deficient and being in the sun is what your body needs to

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Rank: 22
Score: 62.243374
Retrieved Text: Sunlight is strongest when it is directly above the sky. This is why health professionals advise that a person must avoid the sun between ten o’clock in the morning to four o’clock in the afternoon. A marathon conducted at exactly twelve noon not only plays havoc on the skin, but also causes heat stroke and dehydration.
If going out in the sun is unavoidable during such hours, a person should wear protective clothing. Protective clothing can reduce the skin’s exposure to sunlight. Long pants protect the legs. Long-sleeved shirts protect the arms. And broad-brimmed hats can protect the face, especially the eyes. Umbrellas are also effective tools in reducing sun exposure.
A sunburn is an actual burn of your skin from the ultraviolet (UV) light from the sun or other UV light sources (ie tanning beds). A sunburn can occur from as little as 15 minutes of midday sun exposure in a very light-skinned person.
The first signs of a sunburn may not appear for a few hours after the UV exposure. Sunburns may often appear “worse” the day after being at the beach, as it can take 24 hours or longer for the full effect of the UV damage to your skin to appear.
Sunburned skin is red and tender skin that is warm to the touch. Severe sunburned skin may result in the formation of blisters. Almost all sunburned skin will result in skin peeling on the burned areas several days after the sunburn.
Take anti-inflammatory medications such as ibuprophen (Advil, Motrin), naproxen (Aleve) or aspirin. Do NOT give

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Rank: 23
Score: 62.23569
Retrieved Text: Best skin care/primers with SPF??
Re: Best skin care/primers with SPF??
@tongxiaowei I recommend the SUPERGOOP! - Unseen Sunscreen Broad Spectrum SPF 40.I have found it works great and feels weightless under my makeup.
Actually, yesterday I discovered that Ulta has their whole Ulta Beauty skincare line 50% off this week. I picked up a bottle of SPF 50 Sunscreen Rose Water Setting Spray for SPF reapplication, will see how it does. Some reviewers even compared it to Coola and Supergoop... $5! They also have Tinted Mineral Face Lotion SPF 30 that I might get and try as a primer under powder foundation. Also $5 this week.
I was originally gonna wait until Sun Safety kit officially drops, and perhaps stock up that way, but I was able to find one in-store and it’s quite low on value this year. You can see my post about that in Skincare Aware. Hence, Ulta! Hope this helps.
I use Tarte tinted primer and BB cream with SPF 20. I wear it every day. It gives me enough coverage that most days I don't even put foundation on top of it.
I really love the SUPERGOOP! - Invincible Setting Powder SPF 45.
The thing with sunscreen is that you typically want to re-apply it after a couple of hours. Since I wear makeup on most days, I prefer a setting powder with SPF so I can use it to touch up my makeup. The SuperGoop! one is my favorite by far, and it's an essential in my makeup bag.
TLDR, I think you’re much better off finding

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Score: 62.105515
Retrieved Text: Always 100% chemical-free actives, Sunforgettable® Total Protection™ Body Shield SPF 50 goes beyond SPF to provide all-mineral, totally invisible daily defense from harmful environmental aggressors.
A powerful antioxidant that helps prevent skin aging due to pollution and other environmental aggressors.
Lipochroman® is a registered trademark of Lipotec, S.A.
Physavie® is a registered trademark of Chemyunion.
UVB exposure causes redness or burning, while UVA exposure causes skin darkening/pigmentation. Protection from both UVA and UVB means this product provides Broad Spectrum protection. Total Protection™ Body Shield SPF 50 provides Broad Spectrum SPF 50 (UVB protection) and PA+++ (UVA protection).
Total Protection™ Body Shield SPF 50 has a PA+++ rating.
We measure our pollution protection by directly measuring free radicals created from UV + pollution events on unprotected skin and skin protected with Sunforgettable® Total Protection™ Body Shield SPF 50. We use a testing technique called electron spin resonance (ESR) that uses a combination of a magnetic field and electron magnetic waves to directly detect the unpaired electrons of free radicals.
Is Total Protection™ Body Shield SPF 50 non-comedogenic?
Yes, Sunforgettable® Total Protection™ Body Shield SPF 50 is non-comedogenic.
Is Total Protection™ Body Shield SPF 50 hypoallergenic?
Yes, Sunforgettable® Total Protection™ Body Shield SPF 50 is hypoallergenic and dermatologist-recommended.
Is Total Protection™ Body Shield SPF 50 gluten free?
Yes, Sunforgettable® Total Protection™ Body Shield SPF 50 is gluten free. People who have gluten allergies may experience sensitivity when using topical products. Total Protection™ Body Shield SPF 50 is gluten free, and therefore, safe for those with Celiac disease. In addition, all Colorescience® products are 100% free from parabens, phthalates, synthetic fragrance,

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Rank: 25
Score: 62.02327
Retrieved Text: Viewed like this, we can see that the 1.6% difference of UV penetration between SPF 60 and SPF 30 is actually doubled. This means that contrary to our third myth, SPF 60 is twice as effective as SPF 30, and SPF 15 is half as effective as SPF 30. All this might be confusing - so if you need, take look at this animation on YouTube.
We also tend to advise that consumers pick higher sunscreens that offer higher SPF,&nbsp;because scientists have observed that when consumers don’t typically get all the full SPF factors written on the bottle. Even if one buys a sunscreen with SPF 30, it is unlikely that they do enjoy the full benefits of SPF 30 - it is better for us to aim for a higher SPF.
Why don’t we get the full benefits then? Well, after investigating scientists found that it was because consumers do not normally apply sunscreen in the right way. Often, consumers do not apply the right amount nor do they apply it evenly, reducing the protection the sunscreen offers.
Because consumers do not have the luxury of the specialist knowledge experts possess, it is not surprising that many continue to apply sunscreen incorrectly.
By running statistics and models, scientists found that failure to apply the right amount in an even manner of an SPF 15 sunscreen actually means that SPF 30 sunscreen has twice UV protection, and therefore twice the protection against skin cancer - because we fail to get the full SPF 15 protection.
To conclude, SPF 30 has twice

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Rank: 26
Score: 61.87335
Retrieved Text: Next to swimwear and sunglasses, sunscreen is the next most important thing to bring when you’re going sailing on the Turkish coast for seven days.
With new ingredients, research and findings coming out every year, protecting your skin from the ravages of UV rays is more confusing than ever, but it doesn’t have to be. Here, we break down the basics of SPF, UVA and UVB.
Physical vs. chemical sunscreens: Zinc oxide and titanium dioxide are the UVA/UVB filters found in mineral or physical sunscreens. These UV filters sit on top of your skin and act as a physical reflector of UV rays, whereas chemical sunscreens (like avobenzone, octocrylene, and everything else difficult to pronounce) are absorbed into your skin and work by absorbing and deactivating UV rays.
Nope, not even an opaque parasol can be considered 100% UV ray-proof.
That being said, most dermatologists feel that the main chemical sunscreens used in market do not have any data to show they are unsafe, says Dr. Chiu. The biggest factor would be if you have very sensitive skin, since chemical sunscreen filters can be irritative.
Unlike in Europe and Asia, where products are required to be labeled with the PA+ system, which tells you about its UVA protection, the U.S. has yet to adopt a system that would inform the consumer about a sunscreen’s UVA protection. So look for words like “broad-spectrum” or “UVA protection” on the label, since SPF tells us nothing about UVA, says Dr. Chiu.
SPF: The SPF number on the sunscreen bottle tells you the theoretical amount of

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Score: 61.566635
Retrieved Text: I was brought up in the carefree, hatless 1970s, when caution was abandoned and sun block barely invented. My mother smeared a thick white paste called Uvistat on our noses. There was no such thing as “waterproof” and we burned often – I remember the skin on my shoulders bubbling with blisters after a particularly long day in the sun.
Forty years later and I could not conceive of such sunny abandonment of my own children’s skincare in the sun, especially given that my youngest is a redhead with skin the colour of clotted cream.
I have made sun protection a life mission to preserve my children’s complexions so that they don’t look as weathered as I do come my age. Proper sun protection also decreases the chances of getting melanoma skin cancer after too much exposure to the sun, which can be a killer in worst-case scenarios.
Paediatric melanomas are extremely rare, says Dr Jennifer Stein, a dermatologist at NYU Langone in the United States, but “children do need sun protection because childhood sunburns have been linked to melanoma later in life”.
So how do you protect your children’s skin – and your own – to preserve not just a great complexion but possibly your health later on, too?
First you need to understand the sun – and specifically its rays. UV light from the sun comes in two types – UVA and UVB. UVA rays penetrate deeply, causing damage to the fundamental structure of your skin by compromising its collagen and elastin, and they are a danger all year-round,

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Rank: 28
Score: 61.32715
Retrieved Text: This branded SPF 30 sunscreen sprayer includes ground shipping.
The SPF 30 Sunscreen Pen Sprayer is a portable sunscreen sprayer that can be branded with your very own custom-designed label. Perfect to giveaway at summertime marketing events and outdoor exhibitions. Available in eight vibrant colors, this SPF 30 sunscreen spray features a convenient pocket clip. The sunscreen is an FDA approved broad spectrum formula that protects against both UVA and UVB rays, reducing the risk of sunburn, skin cancer and premature skin aging. Full-color label printing is included in our price. Free ground shipping.
Available ColorsFrosted Cap: Blue, Green, Orange, Red, Purple, Pink, Clear or Black.
Free SetupPrice includes 4-color process printing on a white label.

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Rank: 29
Score: 61.195457
Retrieved Text: The NIVEA Men Energy Broad Spectrum SPF 15 Sunscreen is a lotion that revitalizes and energizes the skin.
It can be used every day as a screen against the ravaging impact of the sun.
It’s a broad spectrum lotion that will protect the skin from both UVA and UVB rays. The biggest plus to this lotion is the energizing nature with the addition of Q10.
The company began making skin cream in 1911. It came in a small, metal tin even from the beginning. It started as an emulsifier lotion that combined oil and water into a mixture that would moisturize skin.
The creator of the cream was Dr. Isaac Lifschutz, but it was a dermatologist professor named Paul Gerson Unna who saw the possibilities.
He brought the new emulsifier to a chemist, and they started a company. They named the cream NIVEA based on the Latin word for snow.
CoEnzyme Q10 is an antioxidant that occurs naturally in the body. It protects cells from damage. Throughout your lifetime, the level of Q10 will rise and fall.
It rises towards its peak at ages 20 to 30, but then it will decline as you age beyond 30. In the skin, Q10 prevents damage and helps produce collagen.
Collagen is what gives skin its elasticity in your youth. Elasticity is the firmness that will fade as you age.
CoEnzyme Q10 stimulates the production of collagen, which leads to less wrinkles and helps avoid skin that looks like leather.
When you need to replace Q10, it makes sense to use a lotion that has the ability to stimulate

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Input Text: Read the passage below and choose the right answer to the following question (choices are Reid or Will ):

The closer to the surface an aquifer is, the easier it is to get the water.


Reid installed an aquifer 20m from the surface. Will installed an aquifer 10m from the surface. Whose aquifer is easier to get water from Reid or Will?

Target Text: Will

#### Retrieved Documents ####

Rank: 0
Score: 71.59231
Retrieved Text: New Jersey’s network of rivers, wetlands and ground water is the source of life from the Pinelands to the Jersey Shore to the Delaware River and beyond. Millions of people depend on New Jersey’s ground water every day for drinking, their economic wellbeing and quality of life.
Save the Source is a campaign by Pinelands Preservation Alliance to protect the 17-trillion gallon Kirkwood-Cohansey Aquifer, a vast reserve of fresh water that underlies southern New Jersey and all of the Pinelands.
The Kirkwood-Cohansey is one of the cleanest aquifers in America. Yet it is threatened by overuse, pollution and degradation.
The future of the aquifer is being set TODAY. Join us as we unveil the stories of people whose lives and livelihoods rely on a healthy groundwater supply. Help us in the coming year as we work to make protection of every drop of water in the Kirkwood-Cohansey a priority.
It contains more than 17 trillion gallons of fresh water and lies beneath most of southern New Jersey.
Water flowing out of the ground from the aquifer represents about 90 percent of all water flowing in the streams and rivers in the Pinelands and southern New Jersey.
It supplies clean, fresh water to the Delaware River and Bay.
It is a “surficial” aquifer meaning it is exposed at the land surface in our wetlands, lakes and streams.
The aquifer is comprised mostly of water-saturated layers of sand and fine gravel and some clay-like material and extends from the land’s surface just beneath our feet to depths of up to about 1000 feet near the shore.
The

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Rank: 1
Score: 70.54135
Retrieved Text: Part 1 of this article (Kincaid, 2002) discussed the primary legislation that drives groundwater and surface water protection efforts in the U.S. at the state and federal levels. Though the programs have contributed to a significant decrease in point sources of pollution to both reservoirs, overall groundwater and surface water quality continue to degrade, a fact which is particularly evident in Florida Springs where increasing nutrient levels are causing diminished water clarity and changes to the ecologic systems. Part 1 argued that one of the primary culprits here is the segregation of legislative measures into separate programs, programs that are slow to recognize the interactions between the two reservoirs and the increasingly apparent fact that pollution to one can and will lead to pollution to the other. The remainder of this article will present some of the basic scientific principles that govern groundwater and surface water interactions and discuss examples of common pollution problems that confront the two reservoirs. Key terms that are common to most technical discussions about groundwater/surface water exchange are described and marked by italic font in the text.
The hydrologic cycle (Figure 1) describes the pattern of continuous water circulation through air, land, and sea that is always active in our global environment. Precipitation that falls on the land surface via rainfall or snow either runs off to streams, lakes, and rivers or seeps into the ground and saturates underlying rocks and soil. The saturated rocks and soil are described as aquifers and the process of filling the aquifers is described as recharge.

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Retrieved Text: Contrary to popular belief, an aquifer is not a free flowing underground river or lake. Actually, an aquifer is a body of rock or sediment that is completely saturated – water is in it and all around it. It can be made of sand, gravel, sandstone, or other rocks that can store or transmit water. What goes in an aquifer stays in an aquifer.
Water that flows into an aquifer may be contaminated by many things we do at or near the surface of the earth. Contaminants may reach the aquifer through natural or man-made pathway. Deliberate disposal of waste such as landfills, septic tanks, and injection wells can have an impact on the quality of an aquifer.
Samples of water taken from the Mahomet Aquifer are routinely dated between 1,000 and 12,000 years old; however, the geological events that lead to the creation of the aquifer were set in motion over a million years ago. The Mahomet Aquifer is composed of sand and gravel that was deposited in the valley of a river that was formed 1.5 million years ago. This ancient river was later disrupted by floods that permanently altered the landscape. The last remnants of this valley were covered by sand, silt, gravel, and clay left by advancing glaciers over 130,000 years ago.
The deposits responsible for producing the aquifers pristine waters are typically found 500 feet below the surface. These deposits average close to 100 feet thick and may be as much as 200 feet in some places. It is only in areas near the

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Rank: 3
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Retrieved Text: Typically, an aquifer receives most of its water inflow from areas known as recharge areas. These are the areas where the aquifer is exposed at the ground surface and the water moves more freely downward through the aquifer materials. This is in contrast to locations where aquifers underlie layers of finer sediment (such as clay). The finer sediments act as barriers to the downward movement of water into the aquifer. In these areas the aquifer is considered to be "confined".
The County of Santa Cruz designates the areas where an aquifer is exposed at the ground surface and allows water to move downward into the aquifer as Primary Groundwater Recharge (PGR) zones. As such, these areas are given special consideration and protection from development. This protection allows the aquifers to maintain an adequate quantity and quality of groundwater recharge. A map of County designated primary groundwater recharge areas is presented below.
Parcels outside the urban services line and within mapped PGR can not be subdivided smaller than 10-acres. The rationale for this is to1) minimize the blockage of the aquifer recharge areas inherent to development and 2) reduce the amount of impacts to the recharge water quality from septic systems and other site activities. An indirect benefit of the lower development density is that it reduces the amount of potential groundwater extraction from those areas.

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Rank: 4
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Retrieved Text: Check out this Springs Friendly Landscaping Checklist to see how you are doing!
Although plants and animals require nutrients, too much of a good thing can be dangerous. Excess nutrients often come from fertilizers, septic systems, wastewater treatment plants, and agriculture lands.
Even if you don't live near a spring you may be affecting the springs because the water that soaks into the ground at your house may travel through underground tunnels and caves to springs miles away. When we use water to irrigate our lawns, wash our clothes and dishes, etc.- we may be contributing to the lower water levels at nearby springs.
Support the acquisition of conservation lands, which are essential for protecting our springs.
Groundwater supplies ALL of our drinking water!
The Floridan aquifer system is located underneath all of Florida and is the primary source of drinking water for Alachua County. (Click HERE to see a map of the Floridan aquifer.) Water is stored and flows through porous limestone and dolomite formations moving northwest to the springs along the Santa Fe and Suwannee Rivers where they discharge into these rivers. The shallow water of the Floridan aquifer system is recharged primarily by rain. Rain water soaks into the ground in the western part of the county where the aquifer is unconfined, which means there is only sand above the limestone and dolomite aquifer. In eastern Alachua County the Floridan aquifer is overlain by clay, sand, and carbonate sequences called the Hawthorn Group. This clay layer keeps rainwater on the surface and causes it to run off and

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Rank: 5
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Retrieved Text: This is a cross section of an aquifer. Florida's 600 natural springs are fed by the Floridan Aquifer. Springs are places where groundwater (in the aquifer) discharges to the surface. When rain falls from the clouds, CO2 is dissolved in the rain drops. The rainwater percolates through the sand and soil on its way to the limestone bedrock of Florida. Once the rainwater hits the limestone, the CO2 dissolves the limestone creating cracks. Over long periods of time, these cracks widen and eventually allow the water from the aquifer to escape to the surface, forming a spring. These springs provide a window into the aquifer.
Crystal Springs is the largest magnitude 2 spring in South Central Florida.

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Rank: 6
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Retrieved Text: Figure 1: baseline monitoring network (with Superficial geology).
Figure 2: baseline monitoring network (with bedrock geology).
There are two significant aquifers across Lancashire: a shallow aquifer formed of superficial glacial sand and gravel interbedded with clay (Figure 1), and a deeper aquifer below formed by the Sherwood Sandstone (Figure 2).
The shallow aquifer is up to 40 m thick and is designated by the Environment Agency as a Secondary B aquifer. It is used for private drinking water supply, farms and golf course irrigation. In the area of the proposed shale–gas sites, this aquifer is underlain by a thick layer (up to 350 m) of a low–permeability mudstone, the Mercia Mudstone. Water moves slowly through this mudstone and it is not classed as an aquifer. Below this is the Sherwood Sandstone, which reaches a thickness of up to 750 m. The Sherwood Sandstone is classed by the Environment Agency as a Principal aquifer.
The Sherwood Sandstone is too deep to be practically accessible in the area below the Fylde. However, to the east of the proposed shale–gas exploration (east of the Woodsfold Fault – see Figure 1), the aquifer is much closer to the surface. In this area it is used for both public and private water supply.
The aquifer units overlie the deeper shale that is the proposed shale–gas target. In the area of the proposed gas–exploration sites, the shale units occur at some 2000 m below surface.
BGS has established a network of water sampling sites consisting of existing boreholes, wells and streams within a radius of some 10 km

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Rank: 7
Score: 67.25703
Retrieved Text: In 2014, IGRAC, together with Acacia Water, carried out a project on Managed Aquifer Recharge (MAR) in the transboundary Merti Aquifer, shared between Kenya and Somalia. The project was commissioned by IGAD Inland Water Resources Management Programme (IGAD-INWRMP), which is an EU funded programme that aims at strengthening the national and regional capacities in the field of water resources management and at the development of regional dialogue and cooperation for sustainable water resources management in the Horn of Africa.
The overall goal of the project was to identify and map the potential for different MAR applications within the Merti aquifer and to develop a MAR data management system. Based on the project results recommendations were given on the potential for different MAR applications in the region.
The IGAD-INWRM team has selected the Merti aquifer, shared between Kenya and Somalia, as pilot transboundary aquifer (TBA) for this project. The Merti aquifer is a large non-renewable aquifer that is one of the few reliable water sources in this semi-arid region. Since the early 1990's there has been a significant increase in population due to the settlement of a large number of refugees from Somalia in the Dadaab area, which led to an increased demand for drinking water. For this drinking water both local population and refugees depend entirely on groundwater. However, although the Merti aquifer is a vital source of fresh water in the region, still relatively little is known about the extent of the aquifer, its hydrogeological parameters and groundwater recharge.
The study has shown that for the Merti aquifer

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Rank: 8
Score: 66.99394
Retrieved Text: Environmental Management | Roger N Smith Associates, Inc. (RNSA) | Specializing in groundwater and environmental professional services in the Portland, Oregon area.
Since 1999 RNSA, has been part of a team investigating the distribution of chlorinated compounds in the Troutdale Aquifer System in the south shore area of the Columbia River near the Portland International Airport. This project is being done under a Consent Order through the State DEQ. RNSA managed the installation of innovative wells using resonant sonic drilling techniques. Since the installation of continuous multi-channeled tubing (CMT) wells, RNSA has been responsible for maintaining and monitoring the well field covering approximately 2 square miles. Successful completion of these wells included a record depth CMT well installation. RNSA also logged and managed the installation of a patented dual-screen groundwater remediation wells. A long term aquifer test was conducted on this well included special management of 2 million gallons of contaminated water, filter the water through activated charcoal filters, cleaning the water for disposal into the nearby slough aquifer characteristics were developed from data collected from 10 pressure transducers in wells within 1/4 mile of the pumping well.
RNSA under contract with the City of Portland Bureau of Environmental Services designed a regional well monitoring network for the Columbia Slough Watershed project area in north Portland. An objective of this project was to identify if aquifer recharge from City street stormwater dry well sumps were impacting an underlying drinking water aquifer system. RNSA developed a monitoring strategy for a nine-square mile study area that is densely populated and

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Rank: 9
Score: 66.48338
Retrieved Text: The bacteria E.coli has been detected in the injected underground water in the Gisborne Managed Aquifer Recharge (MAR) trial, but there is no indication it survived, says Gisborne District Council environmental monitoring team leader Peter Hancock.
He also said there had been no indication of arsenic release.
He was responding to a Stuff story looking into MAR trials.
The story said on the Poverty Bay Flats, water is injected through wells to reach the deep aquifer below. In another trial in Canterbury, the underground reservoir sits closer to the surface, so water from the Rangitata River is diverted into filtration ponds, where it is left to percolate naturally into the aquifer.
Early results from both schemes show the method works, in terms of raising the water level in the underground storage aquifers.
But there were risks, the Stuff report noted. It said that in Poverty Bay, the injection water introduced E.coli bacteria.
The river water being injected was oxygen-rich, while the aquifer water was not. Stuff said that the trial report noted the mixing of the two “could in some cases cause pyrite oxidation and the release of arsenic in the aquifer”.
GNS head of hydrology Stewart Cameron is quoted in the article as saying mixing waters of different chemical composition can cause “odd reactions”. He said MAR could work in New Zealand, but one of the biggest barriers was that not enough was known about what was in the country’s aquifers, and how they worked.
Mr Hancock said from the results of the ongoing monitoring programme, the council had no indication of arsenic

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Rank: 10
Score: 66.012665
Retrieved Text: Note: Contaminants with dates indicate results from the most recent testing done in accordance with regulations.
Maximum Contaminant Level (MCL) – The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to the MCLGs as feasible using the best available treatment technology.
Maximum Contaminant Level Goal (MCLG) — The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.
ppb — parts per billion.
ppm — parts per million.
Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water posed a health risk. More information about contaminants or potential health effects can be obtained by calling the Environmental Protection Agency’s Safe Drinking Water Hotline (800-426-4791).
If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. LAKESIDE WATER SUPPLY is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods and

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Rank: 11
Score: 65.85135
Retrieved Text: At our January 14, 2019 evening meeting at the Commack Public library , CCA hosted speakers from the Suffolk County water Authority. One of the speakers was a 2009 graduate of Commack High school: Seth Wallach !
The water authority always offers an outstanding presentation regarding our drinking water. This was their second visit to a CCA meeting ! Take a field trip on a Thursday afternoon tour of the water authority educational showcase in Hauppauge. Call the water authority for details..
Seventy percent of the SCWA wells do not require treatment. Of the wells that require treatment, 119 GAC tank carbon filters have been installed and are maintained by Calgon water technicians ..
The charcoal carbon filters are being replaced with coconut shells which remove even more pollutants.
There are also 29 Iron/manganese removal systems to clear these elements which can clog pipes.
There is a new material being used for water pipes It is called Ductile iron concrete lined pipe. It should last much longer than current materials.
A test system to remove 1-4 dioxane is working well enough to be approved by the Dept of Health.
Lime is added to the water to maintain a neutral (7) ph factor .
Much of Long island is over an aquifer. The deepest purest aquifer is the Lloyd aquifer. Only Long Beach and Atlantic Beach draw pure water from the Lloyd due to salt water intrusion into their wells in the Magothy aquifer..
As more water is pumped from the Magothy water aquifer, which supplies our water, more salt water intrusion occurs.
A heat pump is

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Rank: 12
Score: 65.62029
Retrieved Text: 22% of drinking water produced by De Watergroep is pumped from the Chalk aquifer. To better understand the capacity of the Chalk and the impact of different users, De Watergroep, the Dutch research institute KWR and VUB start a project to contribute to sustainable groundwater exploitation. Two postdoctoral researchers from the research group of prof. Marijke Huysmans from the Department of Hydrology and Hydraulic Engineering (HYDR) of VUB will study the capacity of this aquifer - taking all different sources of uncertainty into account - in this three-year project.
De Watergroep produces 140 million m³ per year. 22% of this quantity is pumped from 29 locations from the Chalk aquifer, an important groundwater bearing subsurface layer in Flemish Brabant, Walloon Brabant and Limburg. This aquifer is also intensively used for industry and agriculture. The Chalk aquifer is exposed at the surface in the north of Wallonia around the axis Waver, Waremme and the valley of the River Jeker. In this area, the aquifer is fed by precipitation and has a phreatic character. Towards the north, this layer dips into the subsurface and is covered by younger clay rich layers that give the Chalk aquifer a confined character. The layer is found at a depth of 96 m in Leuven, 226 m in Aarschot and 150 m in Hasselt. Because of this large depth, the groundwater is well protected from influences from above. Therefore, the Chalk aquifer is a strategic water bearing layer containing pure groundwater.
The governing parameter for groundwater flow, such as permeability and porosity, of the

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Rank: 13
Score: 65.34714
Retrieved Text: The high-temperature and liquid-dominated Mahanagdong geothermal field has supplied steam since 1997 to power plants with total installed capacity of 180 MWe. A geochemical assessment of the field is presented based on analytical data of fluids sampled at the wellheads of 26 wet-steam wells. The pH of the liquid samples ranges from 3 to 8 as measured on-site. Analyses of the water samples include major and minor elements. With the aid of speciation programs, the analytical data were used to model individual species activities in the initial aquifer fluids that feed the wells. The modelling indicates that excess discharge enthalpy of wells is mostly caused by phase segregation of the vapour and liquid phases in producing aquifers. The modelled aquifer fluid compositions were used to assess how closely equilibrium is approached between solution and various minerals.
At inferred Mahanagdong aquifer temperatures (250-300°C), the concentrations of H2S and H2 in the initial aquifer fluids, assuming they are purely liquid, are somewhat higher than those at equilibrium with hydrothermal mineral assemblages, one of which incorporates grossular, pyrite, magnetite and wollastonite, and the other hematite, magnetite and pyrite. The equilibrium constant for both buffers is very similar. The observed distribution of the data points for the gases is attributed to the presence of equilibrium vapour in the aquifer fluid. The concentrations of H2,aq show more scatter. Aquifer fluid concentrations of CO2,aq are slightly above equilibrium curve for both of the assemblages considered (czo+cal+qtz+gro and czo+cal+qtz+gro+pre). However, variation in the composition of the solid-solution minerals may also contribute as well as

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Rank: 14
Score: 65.277985
Retrieved Text: The fresh water that flows through rocks and open spaces below the Earth’s surface is known in environmental science as groundwater. Most of the fresh water that people access is groundwater, flowing underground.
Unconfined aquifers: Water in an unconfined aquifer is stored in permeable rocks and sediment through which it can flow freely. Hence, water in this type of aquifer can flow to plant roots or bubble up to the surface as a spring.
The water table is the boundary between the water-filled rock and sediment of an aquifer and the dry rock and sediment above it. Water that seeps into the ground through the water table when it rains, refills, or recharges, the groundwater in unconfined aquifers.
Confined aquifers: Confined aquifers are surrounded by impermeable layers of rock that don’t allow water to move through them. Thus, confined aquifers create underground storage containers for the water they contain. Because impermeable rock layers surround confined aquifers, they have a specific area of recharge, where fresh water from rainfall can enter and refill the aquifer.
To withdraw groundwater stored in both types of aquifers, people dig wells. Unfortunately, the rate of recharge for most groundwater aquifers is much slower than the rate of withdrawal through wells to meet human water needs. As a result, many existing wells are now dry wells, where no more water can be drawn, and cones of depression form in the water table.
A cone of depression is an area where the water table dips because water has been withdrawn from that area of the aquifer faster than

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Rank: 15
Score: 65.063286
Retrieved Text: Why does TMWA store water underground?
During low water years and in abundant snow years, Truckee Meadows Water Authority (TMWA) carefully manages our water resources. Our water supply depends on annual snowpack and reservoir levels. Since we can’t predict how much snow we will get in any given winter, this is stored water that the community can use if there is a drought. This benefits everyone in the Truckee Meadows. One of those resources is our capacity to store water underground in the aquifer; this storage is in addition to upstream reservoir storage. Both surface and groundwater resources can be tapped in the event of a drought. By injecting treated surface water into some of its wells, TMWA recharges the underground aquifer annually.
The recharge program, known as Aquifer Storage and Recovery (ASR), pipes treated surface water into existing wells. This treated, surface water is injected into the aquifer through several wells throughout TMWA’s service area. The process occurs during fall and winter when water use drops to one-fourth of the summer average usage and surface water is available. The stored water can then be accessed during drought periods, if necessary. The earlier in the fall that TMWA can start injecting treated water into our wells throughout Reno and Sparks, the more water can be stored and available for use in below normal precipitation years. We use the replenished aquifers like underground reservoirs from which water can be withdrawn in the event of reduced availability of river supplies.
How much water has TMWA recharged?
Since recharge began in 1993, ASR

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Rank: 16
Score: 65.06053
Retrieved Text: In addition to being invisible, groundwater is a 'horizontal' resource (in spite of the verticality of wells that abstract groundwater from aquifers), i.e. farmers located above an aquifer can sink wells independently of each other over a significant areal extension depending on the size of the aquifer. For example, in Mexico some aquifers have an area of only a few square kilometres, whereas the Guarani aquifer system in South America has an area of 1.2 million square kilometres, i.e. the size of England, France and Spain combined (World Bank, 2003).
Therefore, groundwater as a resource - in a situation of abundance - is distributed in an equitable manner to those above a given aquifer. With the less-pronounced upstream-downstream dimension, which is so defining in surface water management, and where upstream users literally have the upper hand over downstream users, the groundwater management challenge is a radically different one. The key issue is to manage a pool resource, which any user who can afford a deep enough well has access to and which therefore can provide benefits to many, but with the focus to make it last for as many users as possible for as long as possible. Groundwater management therefore implies dealing with decentralized stakeholders who will make their decisions based on private utility, weighing their costs (sinking the well, variable abstraction costs, etc.) and their benefits (well yields, type of use, benefit derived from it, etc.). Compared to surface water management, there is no 'tap' in the form of a reservoir release or an irrigation gate

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Rank: 17
Score: 64.889015
Retrieved Text: Groundwater is the water found beneath the Earth’s surface and occupies the very small cracks and spaces between rocks, gravel and sand. It is a common misconception that groundwater is in the form of underground lakes, streams and rivers, when in reality, groundwater is found inside rocks: in the small pore spaces between rock grains in sedimentary rocks, between sand and gravel particles in alluvial deposits, or in narrow fractures and faults in crystalline rocks (Water Education Colorado [WEC], 2005, 2007; Colorado Geological Survey [CGS], 2002, 2003).
Groundwater supplies are available throughout much of Colorado; however, while most of state’s surface water resources are found west of the Continental Divide, most of the state’s groundwater resources lie to the east of the Divide (Grigg, 2003; Pearl, 1980). Of Colorado’s 64 counties, 19 rely heavily on the state’s groundwater resources, with private wells and public water supply systems serving approximately 20% of the population. (CGS, n.d., 2002; State of Colorado, 2015). Agriculture also heavily relies on groundwater, mainly for irrigation, but also for livestock and rural domestic needs (CGS, n.d.).
Groundwater Diagram. Department of Environment & Conservation, Government of Newfoundland & Labrador (2016).
Groundwater that is hydrologically connected to a surface stream and which has the ability to influence the amount or direction of flow of water in that stream is referred to as tributary. In Colorado, all groundwater is presumed to be tributary to a surface stream (unless otherwise defined) and is treated like surface waters under the prior appropriation doctrine administered by the Office of the State Engineer.
Streams

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Rank: 18
Score: 64.86251
Retrieved Text: Bentonite Chips/Pellets are made of Premium high Swelling Natural Sodium Bentonite. These form a flexible, permanent, non-toxic seal where water flows and hydrostatic pressures are involved.
Sizes are available in 5 to 10 mm (1/4 to 3/8 inch) and any Bespoke solutions would be available.
Seal all types of well sealing, abandonment, seismic shot holes, grounding rods, mineral exploration holes, etc.
Seal surface casing for water wells and well pits.
Provide an intermediate seal, preventing inter-aquifer transfer.
Seal at the upper most aquifer and prevent entrance of surface water into aquifer.
Seal abandoned wells maintaining aquifer yield and artesian head.
Increased hardness and density provide better settling characteristics. Can be placed in a dry or wet borehole with the same ease as pea gravel.
Extremely slow swelling rate allow the proper placement of the Bentonite seal without bridging.
Will swell up to 15 times its dry volume when hydrated by fresh water.
It will provide an “in place” expansive seal.
Superior characteristics where low permeability flexible seals are required.
It will not shrink or crack with time.

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Rank: 19
Score: 64.73508
Retrieved Text: Movement of agricultural chemicals alachlor, atrazine, cyanazine, deethylatrazine, deisopropylatrazine, and metolachlor between surface water and ground water is documented by data collected from May 1989 through July 1991 at an unfarmed study site adjacent to the Cedar River in Iowa. During periods of runoff, these chemicals moved from the Cedar River into the alluvial aquifer with bank-storage water. Results of simulation of ground-water flow conditions during March-April 1990 indicated that bank-storage water moving through the river bottom accounted for 70 percent of the total bank-storage water, whereas the remaining 30 percent moved through the riverbank. The largest concentrations of the chemicals in bank-storage water during 1990 were: alachlor, 2.1 micrograms per liter (μg/L); atrazine, 4.7 μg/L; cyanazine, 3.2 μg/L; deethylatrazine, 0.54 μg/L; deisopropylatrazine, 0.33 μg/L; and metolachlor, 2.2 μg/L. Larger concentrations of some herbicides and their metabolites were detected in the ground water after the study site was inundated by floodwater between June and August 1990. The concentrations in a water sample from one well after this flooding on February 5, 1991, were: alachlor, 0.06 μg/L; atrazine, 18 μg/L; cyanazine, 1.3 μg/L; deethylatrazine, 1.4 μg/L; deisopropylatrazine, 0.40 μg/L; and metolachlor, 7.0 μg/L.
During base-flow conditions, the movement of agricultural chemicals from ground water to surface water was quantified for two periods of time in 1989 and 1990 along a 117-kilometer reach of the Cedar River. The principal source of atrazine, deethylatrazine, deisopropylatrazine, and metolachlor in the Cedar River during base flow was ground water discharged directly from the alluvial aquifer adjacent to the Cedar River. This discharge

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Rank: 20
Score: 64.55844
Retrieved Text: San Antonio Water Systems has the Largest ASR in the state, (above).
The fourth National Climate Assessment (NCA) has made it crystal clear how the challenges of climate change are impacting our aquifers across the country. Municipalities are turning to new technologies to meet water demands. For many entities, investing in Aquifer Storage and Recovery (ASR) systems seems like a viable solution.
ASR works like this: during times of plentiful water, extra water can be withdrawn from a river (or other source) and then injected and stored within an aquifer. When the original water source runs low due to drought, low rainfall or other causes, this water can then be pulled from the aquifer and used. Some ASR facilities inject treated wastewater rather than surface water into an aquifer, while other facilities inject groundwater from a different aquifer.
Currently, ASR is utilized in 11 countries. There are 95 facilities in the United States. El Paso, Kerrville and San Antonio were the first three major cities in the state to implement ASR.
Austin Water cites ASR as one of it’s major strategies in their innovative new 100 Year Water Plan called “Water Forward”. They believe ASR will help the city become more resilient in the face of challenges like growing water demands and inevitable drought periods, and makes it less likely that the city will eventually need to import water or take other drastic measures.
In Hays County, scientists at the Barton Springs Edwards Aquifer Conservation District (BSEACD) are looking at ASR as a potential means to alleviate pressure on the aquifer

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Rank: 21
Score: 64.48043
Retrieved Text: With the artesian level as much as 100 feet above sea level and the land surface is seldom more than 200 feet, a Sabal Trail pipeline drilling frac-out wouldn’t have to go far to get into the Floridan Aquifer groundwater used by wells around here. We already saw such water contamination would go underground is hard to predict. This is not news: here’s a paper from 1966 with the main points.
Artesian Water in Tertiary Limestone in the Southeastern States, By V. T. Stringfield, GEOLOGICAL SURVEY PROFESSIONAL PAPER 517, 1966.
The piezometric surface, or the height (with reference to sea level) to which water in an artesian aquifer would rise in wells, shows the chief areas of recharge and discharge and direction of lateral movement of the artesian water. In general, the high areas of the piezometric surface indicate recharge, and the low areas indicate discharge. Recharge may, however, occur in some of the areas of relatively low pressure. The piezometric surface ranges from sea level near some coastal areas to more than 120 feet above sea level in the lake region of central Florida and in the Jackson County area in western Florida. The piezometric surface is as much as 250 feet above sea level in an outcrop area of the aquifer, extending from southeastern Alabama northeastward across Georgia to South Carolina.
Joints or fractures and bedding planes may have a pronounced effect on the patterns and movement of water in limestone and associated rocks. Solution features, such as vertical pipes or natural wells, in the limestone appear

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Rank: 22
Score: 64.080475
Retrieved Text: Potable water is a constant source of concern for municipalities, farmers, and other industries. In times of drought, the lack of water can have a significant economic, environmental, and sociological impact on a community. However, the water professionals of Hydro Resources provide a solution to drought-related concerns with our aquifer storage & recovery (ASR) methods.
Most aquifers consist of several layers. The portion closest to the earth’s surface is where fresh, or groundwater, is stored in porous rock. As water levels fluctuate with the seasons, there may be more or less water in the aquifer.
Across the Western US, many of our clients are finding that they require a water supply that includes both surface and groundwater supplies. During periods of low water demand, available surface water can be treated and injected into the aquifer with an ASR well. This water is stored in the aquifer, and is then available for use during high demand periods when surface water supplies may be limited.
Hydro Resources’ team of professionals has vast experience drilling, constructing and equipping ASR wells. Well equipping includes specialized components that allow for water injection and water extraction using the same pumping equipment. Contact us today to discuss your ASR project.

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Rank: 23
Score: 63.568645
Retrieved Text: Investigations into possible causes and consequences of the recent detection of bacteria in aquifer water supplied to Lower Hutt and Wellington are now well under way.
In mid-April Wellington Water recorded the third positive E. coli result from aquifer water in five months. In consultation with Regional Public Health, the decision was made to add chlorine to the water supplied to Lower Hutt, and to turn off the public taps at Buick Street and Dowse Square.
About half of all the water supplied to urban Wellington’s 400,000 people comes from the Waiwhetu Aquifer, which extends under the Hutt Valley and beneath Wellington Harbour. Aquifer water sent to Wellington city has always been chlorinated.
Wellington Water had been tracking an unprecedented increase in bacterial activity in the water taken from the aquifer since February, said the Group Manager of Network Strategy and Planning, Mark Kinvig. “In addition to finding E. coli there has been a general increase in detection of total coliform bacteria, which we have not previously seen.
Investigations into possible sources of contamination are focusing on the security of the bores which draw water from the aquifer. The bore casings descend some 30 metres below ground level into the aquifer, so the casing seals and boreheads at the surface are being tested to ensure they are not leaking. This work is set to be complete in mid-June, after which decisions on long term treatment requirements can be made.
Wellington Water is also looking at other underground pipework in the vicinity of the borefield, and helping scientists from Greater Wellington Regional

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Rank: 24
Score: 63.23807
Retrieved Text: The City of San Marcos is a member of the Hays Caldwell Public Utility Agency (HCPUA). The purpose of the Agency is to resolve long-term water needs for it participants.
The City of San Marcos pumps groundwater from the Edwards Aquifer. The Edwards Aquifer Authority (EAA) manages and regulates the Aquifer.
The City of San Marcos pumps surface water from Canyon Lake. These water rights are governed by the Guadalupe-Blanco River Authority (GBRA).

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Rank: 25
Score: 63.156647
Retrieved Text: Acting Chief Operating Officer for N3B Los Alamos Joe Legare, N3B’s RDX Program Lead Pat McGuire and Chief Scientist Danny Katzman brought members of the Regional Coalition of LANL Communities board up-to-date on the RDX Project at the RCLC’s regular meeting Friday in Espanola.
Legare gave the board an overview of N3B’s structure and current activities as the Legacy Waste cleanup contractor at Los Alamos National Laboratory. Legare noted that there are still some “known unknowns”, the contractor has a very good understanding of the nature and status of contamination across the Lab. He said there’s always competition for funding between the cleanup sites and that historically the funding at Los Alamos has been excellent.
“The best way that I know of to continue that support is to be successful in what we’re doing,” Legare told the board.
McGuire said he hoped board member would come to the conclusion after his presentation that RDX is not within the water supply and that the Department of Energy has an active program to monitor the situation.
McGuire explained that back in the 1950s, facilities were built in the northwest section of the Lab in TA-16 with the purpose of developing and machining high explosives including RDX. During that process he said water was used which came into contact with RDX. That wastewater was then discharged through a pipe from Outfall 260, came into contact with the surface soils and continued to drain down into the Canyon De Valle.
“In the mid-1990s an investigation was conducted and it was determined that RDX was in

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Rank: 26
Score: 63.144875
Retrieved Text: This revisit of the stream-aquifer problem is based on a recent flux-based Green element formulation which offers more accurate solutions than previous formulations presented in Taigbenu (2003). Its accuracy also surpasses those provided by finite element and finite difference methods using grids that are coarser. As in all Green element formulations, the current formulation is predicated on the singular boundary integral theory that is implemented in an element-by-element fashion. What is new in the current formulation is that it calculates the fluxes at all nodes and not only at external nodes. While this approach exhibits much improved accuracy, its drawback lies with handling an increased number of unknowns. This drawback is, however, compensated for by the fewer elements required to achieve accuracies comparable to other conventional numerical methods. In this paper, it is demonstrated that with between 20% and 30% of elements used in finite element and finite difference models, comparable accuracy is achieved with this formulation. The main significance of the current computational technique is that it preserves the flux calculations in a manner that is consistent with the stream-aquifer interaction problem.
While the estimation of stream-aquifer fluxes continues to attract the attention of hydrologists who understand that the fluxes are different manifestations of a unitary water system (the hydrological cycle), arid and semi-arid areas present the most critical areas where the fluxes are the life-line of streams and rivers (Butterworth et al., 1999). The traditional approach to estimating these fluxes is through classical hydrological methodology of hydrograph separation using the distinguishing characteristics in time scales

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Rank: 27
Score: 63.12475
Retrieved Text: Natural springs can be found in all shapes and sizes, all over the world. From a small trickle of water filtering through leaves on a forest floor to the spring fed Lake Itasca in Minnesota - the source of the mighty Mississippi river. Springs typically occur along hillsides, low-lying areas, or at the base of slopes.
Technically, a spring is the result of an aquifer being filled to the point that the water spills out above ground. Springs may be classified according to the geologic formation from which they obtain their water, such as limestone springs or lava-rock springs; or according to the amount of water they discharge, or according to the temperature of the water, or by the forces causing the spring-gravity or artesian flow.
The amount of water that flows from springs depends on many factors, including the size of the caverns within the rocks, the water pressure in the aquifer, the size of the spring basin, and the amount of rainfall. Springs range in size from intermittent seeps, which flow only after much rain, to huge pools flowing hundreds of millions of gallons daily. Small springs are found in many places. Springs may be formed in any sort of rock.
Human activities also can influence the volume of water that discharges from a spring—ground-water withdrawals in an area can reduce the pressure in an aquifer, causing water levels in the aquifer system to drop and ultimately decreasing the flow from the spring.
Springs are not limited to the Earth's surface, though. Recently, scientists have discovered hot springs

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Rank: 28
Score: 62.944866
Retrieved Text: The hydrologic framework of the Santa Clara Valley in northern California was redefined on the basis of new data and a new hydrologic model. The regional groundwater flow systems can be subdivided into upper-aquifer and lower-aquifer systems that form a convergent flow system within a basin bounded by mountains and hills on three sides and discharge to pumping wells and the southern San Francisco Bay. Faults also control the flow of groundwater within the Santa Clara Valley and subdivide the aquifer system into three subregions.
After decades of development and groundwater depletion that resulted in substantial land subsidence, Santa Clara Valley Water District (SCVWD) and the local water purveyors have refilled the basin through conservation and importation of water for direct use and artificial recharge. The natural flow system has been altered by extensive development with flow paths toward major well fields. Climate has not only affected the cycles of sedimentation during the glacial periods over the past million years, but interannual to interdecadal climate cycles also have affected the supply and demand components of the natural and anthropogenic inflows and outflows of water in the valley. Streamflow has been affected by development of the aquifer system and regulated flow from reservoirs, as well as conjunctive use of groundwater and surface water. Interaquifer flow through water- supply wells screened across multiple aquifers is an important component to the flow of groundwater and recapture of artificial recharge in the Santa Clara Valley. Wellbore flow and depth-dependent chemical and isotopic data indicate that flow into wells from multiple aquifers,

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Rank: 29
Score: 62.912186
Retrieved Text: Safety hazards to people and animals.
The plugging of an abandoned well needs to meet requirements outlined in the SD Well Construction Standards sections 74:02:04:67 and 74:02:04:69. These rules specify how to plug a well depending on the type of well construction, the type of aquifer or aquifers which the well penetrates, and the materials to be used to plug the well. Even though the owner of an abandoned well may plug the well, it is strongly suggested that a SD licensed well driller perform the work due to the varying conditions encountered in plugging an abandoned well. If a well is not plugged properly, ground water contamination may still occur and it is very difficult and expensive to correct the improper plugging of an abandoned well.
Historical Background. Abandoned wells exist throughout South Dakota and tap into every principle aquifer in the state. These are the same aquifers that are relied on today for much of the drinking water used in the state. While the actual number of abandoned wells is not known, it is possible to make some reasonable estimates of the number of abandoned wells. In 1910, South Dakota had approximately 78,000 farms which reached a maximum of 84,300 farms in 1932. Since that time, farm numbers have declined steadily to about 31,700 today. Therefore, South Dakota has lost approximately 52,600 farms that likely had at least one well which may now be abandoned. Aside from the reduction in the number of farmsteads, other factors have also contributed to the creation of abandoned wells such

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======= Instance Index 1646 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are Reid or Will ):

The closer to the surface an aquifer is, the easier it is to get the water.


Reid installed an aquifer 20m from the surface. Will installed an aquifer 10m from the surface. Whose aquifer is harder to get water from Reid or Will?

Target Text: Reid

#### Retrieved Documents ####

Rank: 0
Score: 71.59231
Retrieved Text: New Jersey’s network of rivers, wetlands and ground water is the source of life from the Pinelands to the Jersey Shore to the Delaware River and beyond. Millions of people depend on New Jersey’s ground water every day for drinking, their economic wellbeing and quality of life.
Save the Source is a campaign by Pinelands Preservation Alliance to protect the 17-trillion gallon Kirkwood-Cohansey Aquifer, a vast reserve of fresh water that underlies southern New Jersey and all of the Pinelands.
The Kirkwood-Cohansey is one of the cleanest aquifers in America. Yet it is threatened by overuse, pollution and degradation.
The future of the aquifer is being set TODAY. Join us as we unveil the stories of people whose lives and livelihoods rely on a healthy groundwater supply. Help us in the coming year as we work to make protection of every drop of water in the Kirkwood-Cohansey a priority.
It contains more than 17 trillion gallons of fresh water and lies beneath most of southern New Jersey.
Water flowing out of the ground from the aquifer represents about 90 percent of all water flowing in the streams and rivers in the Pinelands and southern New Jersey.
It supplies clean, fresh water to the Delaware River and Bay.
It is a “surficial” aquifer meaning it is exposed at the land surface in our wetlands, lakes and streams.
The aquifer is comprised mostly of water-saturated layers of sand and fine gravel and some clay-like material and extends from the land’s surface just beneath our feet to depths of up to about 1000 feet near the shore.
The

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Rank: 1
Score: 70.54135
Retrieved Text: Part 1 of this article (Kincaid, 2002) discussed the primary legislation that drives groundwater and surface water protection efforts in the U.S. at the state and federal levels. Though the programs have contributed to a significant decrease in point sources of pollution to both reservoirs, overall groundwater and surface water quality continue to degrade, a fact which is particularly evident in Florida Springs where increasing nutrient levels are causing diminished water clarity and changes to the ecologic systems. Part 1 argued that one of the primary culprits here is the segregation of legislative measures into separate programs, programs that are slow to recognize the interactions between the two reservoirs and the increasingly apparent fact that pollution to one can and will lead to pollution to the other. The remainder of this article will present some of the basic scientific principles that govern groundwater and surface water interactions and discuss examples of common pollution problems that confront the two reservoirs. Key terms that are common to most technical discussions about groundwater/surface water exchange are described and marked by italic font in the text.
The hydrologic cycle (Figure 1) describes the pattern of continuous water circulation through air, land, and sea that is always active in our global environment. Precipitation that falls on the land surface via rainfall or snow either runs off to streams, lakes, and rivers or seeps into the ground and saturates underlying rocks and soil. The saturated rocks and soil are described as aquifers and the process of filling the aquifers is described as recharge.

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Rank: 2
Score: 69.9174
Retrieved Text: Contrary to popular belief, an aquifer is not a free flowing underground river or lake. Actually, an aquifer is a body of rock or sediment that is completely saturated – water is in it and all around it. It can be made of sand, gravel, sandstone, or other rocks that can store or transmit water. What goes in an aquifer stays in an aquifer.
Water that flows into an aquifer may be contaminated by many things we do at or near the surface of the earth. Contaminants may reach the aquifer through natural or man-made pathway. Deliberate disposal of waste such as landfills, septic tanks, and injection wells can have an impact on the quality of an aquifer.
Samples of water taken from the Mahomet Aquifer are routinely dated between 1,000 and 12,000 years old; however, the geological events that lead to the creation of the aquifer were set in motion over a million years ago. The Mahomet Aquifer is composed of sand and gravel that was deposited in the valley of a river that was formed 1.5 million years ago. This ancient river was later disrupted by floods that permanently altered the landscape. The last remnants of this valley were covered by sand, silt, gravel, and clay left by advancing glaciers over 130,000 years ago.
The deposits responsible for producing the aquifers pristine waters are typically found 500 feet below the surface. These deposits average close to 100 feet thick and may be as much as 200 feet in some places. It is only in areas near the

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Rank: 3
Score: 69.113144
Retrieved Text: Typically, an aquifer receives most of its water inflow from areas known as recharge areas. These are the areas where the aquifer is exposed at the ground surface and the water moves more freely downward through the aquifer materials. This is in contrast to locations where aquifers underlie layers of finer sediment (such as clay). The finer sediments act as barriers to the downward movement of water into the aquifer. In these areas the aquifer is considered to be "confined".
The County of Santa Cruz designates the areas where an aquifer is exposed at the ground surface and allows water to move downward into the aquifer as Primary Groundwater Recharge (PGR) zones. As such, these areas are given special consideration and protection from development. This protection allows the aquifers to maintain an adequate quantity and quality of groundwater recharge. A map of County designated primary groundwater recharge areas is presented below.
Parcels outside the urban services line and within mapped PGR can not be subdivided smaller than 10-acres. The rationale for this is to1) minimize the blockage of the aquifer recharge areas inherent to development and 2) reduce the amount of impacts to the recharge water quality from septic systems and other site activities. An indirect benefit of the lower development density is that it reduces the amount of potential groundwater extraction from those areas.

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Rank: 4
Score: 68.45123
Retrieved Text: Check out this Springs Friendly Landscaping Checklist to see how you are doing!
Although plants and animals require nutrients, too much of a good thing can be dangerous. Excess nutrients often come from fertilizers, septic systems, wastewater treatment plants, and agriculture lands.
Even if you don't live near a spring you may be affecting the springs because the water that soaks into the ground at your house may travel through underground tunnels and caves to springs miles away. When we use water to irrigate our lawns, wash our clothes and dishes, etc.- we may be contributing to the lower water levels at nearby springs.
Support the acquisition of conservation lands, which are essential for protecting our springs.
Groundwater supplies ALL of our drinking water!
The Floridan aquifer system is located underneath all of Florida and is the primary source of drinking water for Alachua County. (Click HERE to see a map of the Floridan aquifer.) Water is stored and flows through porous limestone and dolomite formations moving northwest to the springs along the Santa Fe and Suwannee Rivers where they discharge into these rivers. The shallow water of the Floridan aquifer system is recharged primarily by rain. Rain water soaks into the ground in the western part of the county where the aquifer is unconfined, which means there is only sand above the limestone and dolomite aquifer. In eastern Alachua County the Floridan aquifer is overlain by clay, sand, and carbonate sequences called the Hawthorn Group. This clay layer keeps rainwater on the surface and causes it to run off and

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Rank: 5
Score: 68.17299
Retrieved Text: This is a cross section of an aquifer. Florida's 600 natural springs are fed by the Floridan Aquifer. Springs are places where groundwater (in the aquifer) discharges to the surface. When rain falls from the clouds, CO2 is dissolved in the rain drops. The rainwater percolates through the sand and soil on its way to the limestone bedrock of Florida. Once the rainwater hits the limestone, the CO2 dissolves the limestone creating cracks. Over long periods of time, these cracks widen and eventually allow the water from the aquifer to escape to the surface, forming a spring. These springs provide a window into the aquifer.
Crystal Springs is the largest magnitude 2 spring in South Central Florida.

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Rank: 6
Score: 67.37662
Retrieved Text: Figure 1: baseline monitoring network (with Superficial geology).
Figure 2: baseline monitoring network (with bedrock geology).
There are two significant aquifers across Lancashire: a shallow aquifer formed of superficial glacial sand and gravel interbedded with clay (Figure 1), and a deeper aquifer below formed by the Sherwood Sandstone (Figure 2).
The shallow aquifer is up to 40 m thick and is designated by the Environment Agency as a Secondary B aquifer. It is used for private drinking water supply, farms and golf course irrigation. In the area of the proposed shale–gas sites, this aquifer is underlain by a thick layer (up to 350 m) of a low–permeability mudstone, the Mercia Mudstone. Water moves slowly through this mudstone and it is not classed as an aquifer. Below this is the Sherwood Sandstone, which reaches a thickness of up to 750 m. The Sherwood Sandstone is classed by the Environment Agency as a Principal aquifer.
The Sherwood Sandstone is too deep to be practically accessible in the area below the Fylde. However, to the east of the proposed shale–gas exploration (east of the Woodsfold Fault – see Figure 1), the aquifer is much closer to the surface. In this area it is used for both public and private water supply.
The aquifer units overlie the deeper shale that is the proposed shale–gas target. In the area of the proposed gas–exploration sites, the shale units occur at some 2000 m below surface.
BGS has established a network of water sampling sites consisting of existing boreholes, wells and streams within a radius of some 10 km

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Rank: 7
Score: 67.25703
Retrieved Text: In 2014, IGRAC, together with Acacia Water, carried out a project on Managed Aquifer Recharge (MAR) in the transboundary Merti Aquifer, shared between Kenya and Somalia. The project was commissioned by IGAD Inland Water Resources Management Programme (IGAD-INWRMP), which is an EU funded programme that aims at strengthening the national and regional capacities in the field of water resources management and at the development of regional dialogue and cooperation for sustainable water resources management in the Horn of Africa.
The overall goal of the project was to identify and map the potential for different MAR applications within the Merti aquifer and to develop a MAR data management system. Based on the project results recommendations were given on the potential for different MAR applications in the region.
The IGAD-INWRM team has selected the Merti aquifer, shared between Kenya and Somalia, as pilot transboundary aquifer (TBA) for this project. The Merti aquifer is a large non-renewable aquifer that is one of the few reliable water sources in this semi-arid region. Since the early 1990's there has been a significant increase in population due to the settlement of a large number of refugees from Somalia in the Dadaab area, which led to an increased demand for drinking water. For this drinking water both local population and refugees depend entirely on groundwater. However, although the Merti aquifer is a vital source of fresh water in the region, still relatively little is known about the extent of the aquifer, its hydrogeological parameters and groundwater recharge.
The study has shown that for the Merti aquifer

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Rank: 8
Score: 66.99394
Retrieved Text: Environmental Management | Roger N Smith Associates, Inc. (RNSA) | Specializing in groundwater and environmental professional services in the Portland, Oregon area.
Since 1999 RNSA, has been part of a team investigating the distribution of chlorinated compounds in the Troutdale Aquifer System in the south shore area of the Columbia River near the Portland International Airport. This project is being done under a Consent Order through the State DEQ. RNSA managed the installation of innovative wells using resonant sonic drilling techniques. Since the installation of continuous multi-channeled tubing (CMT) wells, RNSA has been responsible for maintaining and monitoring the well field covering approximately 2 square miles. Successful completion of these wells included a record depth CMT well installation. RNSA also logged and managed the installation of a patented dual-screen groundwater remediation wells. A long term aquifer test was conducted on this well included special management of 2 million gallons of contaminated water, filter the water through activated charcoal filters, cleaning the water for disposal into the nearby slough aquifer characteristics were developed from data collected from 10 pressure transducers in wells within 1/4 mile of the pumping well.
RNSA under contract with the City of Portland Bureau of Environmental Services designed a regional well monitoring network for the Columbia Slough Watershed project area in north Portland. An objective of this project was to identify if aquifer recharge from City street stormwater dry well sumps were impacting an underlying drinking water aquifer system. RNSA developed a monitoring strategy for a nine-square mile study area that is densely populated and

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Rank: 9
Score: 66.48338
Retrieved Text: The bacteria E.coli has been detected in the injected underground water in the Gisborne Managed Aquifer Recharge (MAR) trial, but there is no indication it survived, says Gisborne District Council environmental monitoring team leader Peter Hancock.
He also said there had been no indication of arsenic release.
He was responding to a Stuff story looking into MAR trials.
The story said on the Poverty Bay Flats, water is injected through wells to reach the deep aquifer below. In another trial in Canterbury, the underground reservoir sits closer to the surface, so water from the Rangitata River is diverted into filtration ponds, where it is left to percolate naturally into the aquifer.
Early results from both schemes show the method works, in terms of raising the water level in the underground storage aquifers.
But there were risks, the Stuff report noted. It said that in Poverty Bay, the injection water introduced E.coli bacteria.
The river water being injected was oxygen-rich, while the aquifer water was not. Stuff said that the trial report noted the mixing of the two “could in some cases cause pyrite oxidation and the release of arsenic in the aquifer”.
GNS head of hydrology Stewart Cameron is quoted in the article as saying mixing waters of different chemical composition can cause “odd reactions”. He said MAR could work in New Zealand, but one of the biggest barriers was that not enough was known about what was in the country’s aquifers, and how they worked.
Mr Hancock said from the results of the ongoing monitoring programme, the council had no indication of arsenic

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Rank: 10
Score: 66.012665
Retrieved Text: Note: Contaminants with dates indicate results from the most recent testing done in accordance with regulations.
Maximum Contaminant Level (MCL) – The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to the MCLGs as feasible using the best available treatment technology.
Maximum Contaminant Level Goal (MCLG) — The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety.
ppb — parts per billion.
ppm — parts per million.
Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of contaminants does not necessarily indicate that water posed a health risk. More information about contaminants or potential health effects can be obtained by calling the Environmental Protection Agency’s Safe Drinking Water Hotline (800-426-4791).
If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. LAKESIDE WATER SUPPLY is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods and

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Rank: 11
Score: 65.85135
Retrieved Text: At our January 14, 2019 evening meeting at the Commack Public library , CCA hosted speakers from the Suffolk County water Authority. One of the speakers was a 2009 graduate of Commack High school: Seth Wallach !
The water authority always offers an outstanding presentation regarding our drinking water. This was their second visit to a CCA meeting ! Take a field trip on a Thursday afternoon tour of the water authority educational showcase in Hauppauge. Call the water authority for details..
Seventy percent of the SCWA wells do not require treatment. Of the wells that require treatment, 119 GAC tank carbon filters have been installed and are maintained by Calgon water technicians ..
The charcoal carbon filters are being replaced with coconut shells which remove even more pollutants.
There are also 29 Iron/manganese removal systems to clear these elements which can clog pipes.
There is a new material being used for water pipes It is called Ductile iron concrete lined pipe. It should last much longer than current materials.
A test system to remove 1-4 dioxane is working well enough to be approved by the Dept of Health.
Lime is added to the water to maintain a neutral (7) ph factor .
Much of Long island is over an aquifer. The deepest purest aquifer is the Lloyd aquifer. Only Long Beach and Atlantic Beach draw pure water from the Lloyd due to salt water intrusion into their wells in the Magothy aquifer..
As more water is pumped from the Magothy water aquifer, which supplies our water, more salt water intrusion occurs.
A heat pump is

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Rank: 12
Score: 65.62029
Retrieved Text: 22% of drinking water produced by De Watergroep is pumped from the Chalk aquifer. To better understand the capacity of the Chalk and the impact of different users, De Watergroep, the Dutch research institute KWR and VUB start a project to contribute to sustainable groundwater exploitation. Two postdoctoral researchers from the research group of prof. Marijke Huysmans from the Department of Hydrology and Hydraulic Engineering (HYDR) of VUB will study the capacity of this aquifer - taking all different sources of uncertainty into account - in this three-year project.
De Watergroep produces 140 million m³ per year. 22% of this quantity is pumped from 29 locations from the Chalk aquifer, an important groundwater bearing subsurface layer in Flemish Brabant, Walloon Brabant and Limburg. This aquifer is also intensively used for industry and agriculture. The Chalk aquifer is exposed at the surface in the north of Wallonia around the axis Waver, Waremme and the valley of the River Jeker. In this area, the aquifer is fed by precipitation and has a phreatic character. Towards the north, this layer dips into the subsurface and is covered by younger clay rich layers that give the Chalk aquifer a confined character. The layer is found at a depth of 96 m in Leuven, 226 m in Aarschot and 150 m in Hasselt. Because of this large depth, the groundwater is well protected from influences from above. Therefore, the Chalk aquifer is a strategic water bearing layer containing pure groundwater.
The governing parameter for groundwater flow, such as permeability and porosity, of the

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Rank: 13
Score: 65.34714
Retrieved Text: The high-temperature and liquid-dominated Mahanagdong geothermal field has supplied steam since 1997 to power plants with total installed capacity of 180 MWe. A geochemical assessment of the field is presented based on analytical data of fluids sampled at the wellheads of 26 wet-steam wells. The pH of the liquid samples ranges from 3 to 8 as measured on-site. Analyses of the water samples include major and minor elements. With the aid of speciation programs, the analytical data were used to model individual species activities in the initial aquifer fluids that feed the wells. The modelling indicates that excess discharge enthalpy of wells is mostly caused by phase segregation of the vapour and liquid phases in producing aquifers. The modelled aquifer fluid compositions were used to assess how closely equilibrium is approached between solution and various minerals.
At inferred Mahanagdong aquifer temperatures (250-300°C), the concentrations of H2S and H2 in the initial aquifer fluids, assuming they are purely liquid, are somewhat higher than those at equilibrium with hydrothermal mineral assemblages, one of which incorporates grossular, pyrite, magnetite and wollastonite, and the other hematite, magnetite and pyrite. The equilibrium constant for both buffers is very similar. The observed distribution of the data points for the gases is attributed to the presence of equilibrium vapour in the aquifer fluid. The concentrations of H2,aq show more scatter. Aquifer fluid concentrations of CO2,aq are slightly above equilibrium curve for both of the assemblages considered (czo+cal+qtz+gro and czo+cal+qtz+gro+pre). However, variation in the composition of the solid-solution minerals may also contribute as well as

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Rank: 14
Score: 65.277985
Retrieved Text: The fresh water that flows through rocks and open spaces below the Earth’s surface is known in environmental science as groundwater. Most of the fresh water that people access is groundwater, flowing underground.
Unconfined aquifers: Water in an unconfined aquifer is stored in permeable rocks and sediment through which it can flow freely. Hence, water in this type of aquifer can flow to plant roots or bubble up to the surface as a spring.
The water table is the boundary between the water-filled rock and sediment of an aquifer and the dry rock and sediment above it. Water that seeps into the ground through the water table when it rains, refills, or recharges, the groundwater in unconfined aquifers.
Confined aquifers: Confined aquifers are surrounded by impermeable layers of rock that don’t allow water to move through them. Thus, confined aquifers create underground storage containers for the water they contain. Because impermeable rock layers surround confined aquifers, they have a specific area of recharge, where fresh water from rainfall can enter and refill the aquifer.
To withdraw groundwater stored in both types of aquifers, people dig wells. Unfortunately, the rate of recharge for most groundwater aquifers is much slower than the rate of withdrawal through wells to meet human water needs. As a result, many existing wells are now dry wells, where no more water can be drawn, and cones of depression form in the water table.
A cone of depression is an area where the water table dips because water has been withdrawn from that area of the aquifer faster than

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Rank: 15
Score: 65.063286
Retrieved Text: Why does TMWA store water underground?
During low water years and in abundant snow years, Truckee Meadows Water Authority (TMWA) carefully manages our water resources. Our water supply depends on annual snowpack and reservoir levels. Since we can’t predict how much snow we will get in any given winter, this is stored water that the community can use if there is a drought. This benefits everyone in the Truckee Meadows. One of those resources is our capacity to store water underground in the aquifer; this storage is in addition to upstream reservoir storage. Both surface and groundwater resources can be tapped in the event of a drought. By injecting treated surface water into some of its wells, TMWA recharges the underground aquifer annually.
The recharge program, known as Aquifer Storage and Recovery (ASR), pipes treated surface water into existing wells. This treated, surface water is injected into the aquifer through several wells throughout TMWA’s service area. The process occurs during fall and winter when water use drops to one-fourth of the summer average usage and surface water is available. The stored water can then be accessed during drought periods, if necessary. The earlier in the fall that TMWA can start injecting treated water into our wells throughout Reno and Sparks, the more water can be stored and available for use in below normal precipitation years. We use the replenished aquifers like underground reservoirs from which water can be withdrawn in the event of reduced availability of river supplies.
How much water has TMWA recharged?
Since recharge began in 1993, ASR

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Score: 65.06053
Retrieved Text: In addition to being invisible, groundwater is a 'horizontal' resource (in spite of the verticality of wells that abstract groundwater from aquifers), i.e. farmers located above an aquifer can sink wells independently of each other over a significant areal extension depending on the size of the aquifer. For example, in Mexico some aquifers have an area of only a few square kilometres, whereas the Guarani aquifer system in South America has an area of 1.2 million square kilometres, i.e. the size of England, France and Spain combined (World Bank, 2003).
Therefore, groundwater as a resource - in a situation of abundance - is distributed in an equitable manner to those above a given aquifer. With the less-pronounced upstream-downstream dimension, which is so defining in surface water management, and where upstream users literally have the upper hand over downstream users, the groundwater management challenge is a radically different one. The key issue is to manage a pool resource, which any user who can afford a deep enough well has access to and which therefore can provide benefits to many, but with the focus to make it last for as many users as possible for as long as possible. Groundwater management therefore implies dealing with decentralized stakeholders who will make their decisions based on private utility, weighing their costs (sinking the well, variable abstraction costs, etc.) and their benefits (well yields, type of use, benefit derived from it, etc.). Compared to surface water management, there is no 'tap' in the form of a reservoir release or an irrigation gate

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Rank: 17
Score: 64.889015
Retrieved Text: Groundwater is the water found beneath the Earth’s surface and occupies the very small cracks and spaces between rocks, gravel and sand. It is a common misconception that groundwater is in the form of underground lakes, streams and rivers, when in reality, groundwater is found inside rocks: in the small pore spaces between rock grains in sedimentary rocks, between sand and gravel particles in alluvial deposits, or in narrow fractures and faults in crystalline rocks (Water Education Colorado [WEC], 2005, 2007; Colorado Geological Survey [CGS], 2002, 2003).
Groundwater supplies are available throughout much of Colorado; however, while most of state’s surface water resources are found west of the Continental Divide, most of the state’s groundwater resources lie to the east of the Divide (Grigg, 2003; Pearl, 1980). Of Colorado’s 64 counties, 19 rely heavily on the state’s groundwater resources, with private wells and public water supply systems serving approximately 20% of the population. (CGS, n.d., 2002; State of Colorado, 2015). Agriculture also heavily relies on groundwater, mainly for irrigation, but also for livestock and rural domestic needs (CGS, n.d.).
Groundwater Diagram. Department of Environment & Conservation, Government of Newfoundland & Labrador (2016).
Groundwater that is hydrologically connected to a surface stream and which has the ability to influence the amount or direction of flow of water in that stream is referred to as tributary. In Colorado, all groundwater is presumed to be tributary to a surface stream (unless otherwise defined) and is treated like surface waters under the prior appropriation doctrine administered by the Office of the State Engineer.
Streams

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Rank: 18
Score: 64.86251
Retrieved Text: Bentonite Chips/Pellets are made of Premium high Swelling Natural Sodium Bentonite. These form a flexible, permanent, non-toxic seal where water flows and hydrostatic pressures are involved.
Sizes are available in 5 to 10 mm (1/4 to 3/8 inch) and any Bespoke solutions would be available.
Seal all types of well sealing, abandonment, seismic shot holes, grounding rods, mineral exploration holes, etc.
Seal surface casing for water wells and well pits.
Provide an intermediate seal, preventing inter-aquifer transfer.
Seal at the upper most aquifer and prevent entrance of surface water into aquifer.
Seal abandoned wells maintaining aquifer yield and artesian head.
Increased hardness and density provide better settling characteristics. Can be placed in a dry or wet borehole with the same ease as pea gravel.
Extremely slow swelling rate allow the proper placement of the Bentonite seal without bridging.
Will swell up to 15 times its dry volume when hydrated by fresh water.
It will provide an “in place” expansive seal.
Superior characteristics where low permeability flexible seals are required.
It will not shrink or crack with time.

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Rank: 19
Score: 64.73508
Retrieved Text: Movement of agricultural chemicals alachlor, atrazine, cyanazine, deethylatrazine, deisopropylatrazine, and metolachlor between surface water and ground water is documented by data collected from May 1989 through July 1991 at an unfarmed study site adjacent to the Cedar River in Iowa. During periods of runoff, these chemicals moved from the Cedar River into the alluvial aquifer with bank-storage water. Results of simulation of ground-water flow conditions during March-April 1990 indicated that bank-storage water moving through the river bottom accounted for 70 percent of the total bank-storage water, whereas the remaining 30 percent moved through the riverbank. The largest concentrations of the chemicals in bank-storage water during 1990 were: alachlor, 2.1 micrograms per liter (μg/L); atrazine, 4.7 μg/L; cyanazine, 3.2 μg/L; deethylatrazine, 0.54 μg/L; deisopropylatrazine, 0.33 μg/L; and metolachlor, 2.2 μg/L. Larger concentrations of some herbicides and their metabolites were detected in the ground water after the study site was inundated by floodwater between June and August 1990. The concentrations in a water sample from one well after this flooding on February 5, 1991, were: alachlor, 0.06 μg/L; atrazine, 18 μg/L; cyanazine, 1.3 μg/L; deethylatrazine, 1.4 μg/L; deisopropylatrazine, 0.40 μg/L; and metolachlor, 7.0 μg/L.
During base-flow conditions, the movement of agricultural chemicals from ground water to surface water was quantified for two periods of time in 1989 and 1990 along a 117-kilometer reach of the Cedar River. The principal source of atrazine, deethylatrazine, deisopropylatrazine, and metolachlor in the Cedar River during base flow was ground water discharged directly from the alluvial aquifer adjacent to the Cedar River. This discharge

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Rank: 20
Score: 64.55844
Retrieved Text: San Antonio Water Systems has the Largest ASR in the state, (above).
The fourth National Climate Assessment (NCA) has made it crystal clear how the challenges of climate change are impacting our aquifers across the country. Municipalities are turning to new technologies to meet water demands. For many entities, investing in Aquifer Storage and Recovery (ASR) systems seems like a viable solution.
ASR works like this: during times of plentiful water, extra water can be withdrawn from a river (or other source) and then injected and stored within an aquifer. When the original water source runs low due to drought, low rainfall or other causes, this water can then be pulled from the aquifer and used. Some ASR facilities inject treated wastewater rather than surface water into an aquifer, while other facilities inject groundwater from a different aquifer.
Currently, ASR is utilized in 11 countries. There are 95 facilities in the United States. El Paso, Kerrville and San Antonio were the first three major cities in the state to implement ASR.
Austin Water cites ASR as one of it’s major strategies in their innovative new 100 Year Water Plan called “Water Forward”. They believe ASR will help the city become more resilient in the face of challenges like growing water demands and inevitable drought periods, and makes it less likely that the city will eventually need to import water or take other drastic measures.
In Hays County, scientists at the Barton Springs Edwards Aquifer Conservation District (BSEACD) are looking at ASR as a potential means to alleviate pressure on the aquifer

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Rank: 21
Score: 64.48043
Retrieved Text: With the artesian level as much as 100 feet above sea level and the land surface is seldom more than 200 feet, a Sabal Trail pipeline drilling frac-out wouldn’t have to go far to get into the Floridan Aquifer groundwater used by wells around here. We already saw such water contamination would go underground is hard to predict. This is not news: here’s a paper from 1966 with the main points.
Artesian Water in Tertiary Limestone in the Southeastern States, By V. T. Stringfield, GEOLOGICAL SURVEY PROFESSIONAL PAPER 517, 1966.
The piezometric surface, or the height (with reference to sea level) to which water in an artesian aquifer would rise in wells, shows the chief areas of recharge and discharge and direction of lateral movement of the artesian water. In general, the high areas of the piezometric surface indicate recharge, and the low areas indicate discharge. Recharge may, however, occur in some of the areas of relatively low pressure. The piezometric surface ranges from sea level near some coastal areas to more than 120 feet above sea level in the lake region of central Florida and in the Jackson County area in western Florida. The piezometric surface is as much as 250 feet above sea level in an outcrop area of the aquifer, extending from southeastern Alabama northeastward across Georgia to South Carolina.
Joints or fractures and bedding planes may have a pronounced effect on the patterns and movement of water in limestone and associated rocks. Solution features, such as vertical pipes or natural wells, in the limestone appear

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Rank: 22
Score: 64.080475
Retrieved Text: Potable water is a constant source of concern for municipalities, farmers, and other industries. In times of drought, the lack of water can have a significant economic, environmental, and sociological impact on a community. However, the water professionals of Hydro Resources provide a solution to drought-related concerns with our aquifer storage & recovery (ASR) methods.
Most aquifers consist of several layers. The portion closest to the earth’s surface is where fresh, or groundwater, is stored in porous rock. As water levels fluctuate with the seasons, there may be more or less water in the aquifer.
Across the Western US, many of our clients are finding that they require a water supply that includes both surface and groundwater supplies. During periods of low water demand, available surface water can be treated and injected into the aquifer with an ASR well. This water is stored in the aquifer, and is then available for use during high demand periods when surface water supplies may be limited.
Hydro Resources’ team of professionals has vast experience drilling, constructing and equipping ASR wells. Well equipping includes specialized components that allow for water injection and water extraction using the same pumping equipment. Contact us today to discuss your ASR project.

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Rank: 23
Score: 63.568645
Retrieved Text: Investigations into possible causes and consequences of the recent detection of bacteria in aquifer water supplied to Lower Hutt and Wellington are now well under way.
In mid-April Wellington Water recorded the third positive E. coli result from aquifer water in five months. In consultation with Regional Public Health, the decision was made to add chlorine to the water supplied to Lower Hutt, and to turn off the public taps at Buick Street and Dowse Square.
About half of all the water supplied to urban Wellington’s 400,000 people comes from the Waiwhetu Aquifer, which extends under the Hutt Valley and beneath Wellington Harbour. Aquifer water sent to Wellington city has always been chlorinated.
Wellington Water had been tracking an unprecedented increase in bacterial activity in the water taken from the aquifer since February, said the Group Manager of Network Strategy and Planning, Mark Kinvig. “In addition to finding E. coli there has been a general increase in detection of total coliform bacteria, which we have not previously seen.
Investigations into possible sources of contamination are focusing on the security of the bores which draw water from the aquifer. The bore casings descend some 30 metres below ground level into the aquifer, so the casing seals and boreheads at the surface are being tested to ensure they are not leaking. This work is set to be complete in mid-June, after which decisions on long term treatment requirements can be made.
Wellington Water is also looking at other underground pipework in the vicinity of the borefield, and helping scientists from Greater Wellington Regional

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Rank: 24
Score: 63.23807
Retrieved Text: The City of San Marcos is a member of the Hays Caldwell Public Utility Agency (HCPUA). The purpose of the Agency is to resolve long-term water needs for it participants.
The City of San Marcos pumps groundwater from the Edwards Aquifer. The Edwards Aquifer Authority (EAA) manages and regulates the Aquifer.
The City of San Marcos pumps surface water from Canyon Lake. These water rights are governed by the Guadalupe-Blanco River Authority (GBRA).

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Rank: 25
Score: 63.156647
Retrieved Text: Acting Chief Operating Officer for N3B Los Alamos Joe Legare, N3B’s RDX Program Lead Pat McGuire and Chief Scientist Danny Katzman brought members of the Regional Coalition of LANL Communities board up-to-date on the RDX Project at the RCLC’s regular meeting Friday in Espanola.
Legare gave the board an overview of N3B’s structure and current activities as the Legacy Waste cleanup contractor at Los Alamos National Laboratory. Legare noted that there are still some “known unknowns”, the contractor has a very good understanding of the nature and status of contamination across the Lab. He said there’s always competition for funding between the cleanup sites and that historically the funding at Los Alamos has been excellent.
“The best way that I know of to continue that support is to be successful in what we’re doing,” Legare told the board.
McGuire said he hoped board member would come to the conclusion after his presentation that RDX is not within the water supply and that the Department of Energy has an active program to monitor the situation.
McGuire explained that back in the 1950s, facilities were built in the northwest section of the Lab in TA-16 with the purpose of developing and machining high explosives including RDX. During that process he said water was used which came into contact with RDX. That wastewater was then discharged through a pipe from Outfall 260, came into contact with the surface soils and continued to drain down into the Canyon De Valle.
“In the mid-1990s an investigation was conducted and it was determined that RDX was in

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Rank: 26
Score: 63.144875
Retrieved Text: This revisit of the stream-aquifer problem is based on a recent flux-based Green element formulation which offers more accurate solutions than previous formulations presented in Taigbenu (2003). Its accuracy also surpasses those provided by finite element and finite difference methods using grids that are coarser. As in all Green element formulations, the current formulation is predicated on the singular boundary integral theory that is implemented in an element-by-element fashion. What is new in the current formulation is that it calculates the fluxes at all nodes and not only at external nodes. While this approach exhibits much improved accuracy, its drawback lies with handling an increased number of unknowns. This drawback is, however, compensated for by the fewer elements required to achieve accuracies comparable to other conventional numerical methods. In this paper, it is demonstrated that with between 20% and 30% of elements used in finite element and finite difference models, comparable accuracy is achieved with this formulation. The main significance of the current computational technique is that it preserves the flux calculations in a manner that is consistent with the stream-aquifer interaction problem.
While the estimation of stream-aquifer fluxes continues to attract the attention of hydrologists who understand that the fluxes are different manifestations of a unitary water system (the hydrological cycle), arid and semi-arid areas present the most critical areas where the fluxes are the life-line of streams and rivers (Butterworth et al., 1999). The traditional approach to estimating these fluxes is through classical hydrological methodology of hydrograph separation using the distinguishing characteristics in time scales

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Rank: 27
Score: 63.12475
Retrieved Text: Natural springs can be found in all shapes and sizes, all over the world. From a small trickle of water filtering through leaves on a forest floor to the spring fed Lake Itasca in Minnesota - the source of the mighty Mississippi river. Springs typically occur along hillsides, low-lying areas, or at the base of slopes.
Technically, a spring is the result of an aquifer being filled to the point that the water spills out above ground. Springs may be classified according to the geologic formation from which they obtain their water, such as limestone springs or lava-rock springs; or according to the amount of water they discharge, or according to the temperature of the water, or by the forces causing the spring-gravity or artesian flow.
The amount of water that flows from springs depends on many factors, including the size of the caverns within the rocks, the water pressure in the aquifer, the size of the spring basin, and the amount of rainfall. Springs range in size from intermittent seeps, which flow only after much rain, to huge pools flowing hundreds of millions of gallons daily. Small springs are found in many places. Springs may be formed in any sort of rock.
Human activities also can influence the volume of water that discharges from a spring—ground-water withdrawals in an area can reduce the pressure in an aquifer, causing water levels in the aquifer system to drop and ultimately decreasing the flow from the spring.
Springs are not limited to the Earth's surface, though. Recently, scientists have discovered hot springs

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Rank: 28
Score: 62.944866
Retrieved Text: The hydrologic framework of the Santa Clara Valley in northern California was redefined on the basis of new data and a new hydrologic model. The regional groundwater flow systems can be subdivided into upper-aquifer and lower-aquifer systems that form a convergent flow system within a basin bounded by mountains and hills on three sides and discharge to pumping wells and the southern San Francisco Bay. Faults also control the flow of groundwater within the Santa Clara Valley and subdivide the aquifer system into three subregions.
After decades of development and groundwater depletion that resulted in substantial land subsidence, Santa Clara Valley Water District (SCVWD) and the local water purveyors have refilled the basin through conservation and importation of water for direct use and artificial recharge. The natural flow system has been altered by extensive development with flow paths toward major well fields. Climate has not only affected the cycles of sedimentation during the glacial periods over the past million years, but interannual to interdecadal climate cycles also have affected the supply and demand components of the natural and anthropogenic inflows and outflows of water in the valley. Streamflow has been affected by development of the aquifer system and regulated flow from reservoirs, as well as conjunctive use of groundwater and surface water. Interaquifer flow through water- supply wells screened across multiple aquifers is an important component to the flow of groundwater and recapture of artificial recharge in the Santa Clara Valley. Wellbore flow and depth-dependent chemical and isotopic data indicate that flow into wells from multiple aquifers,

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Rank: 29
Score: 62.912186
Retrieved Text: Safety hazards to people and animals.
The plugging of an abandoned well needs to meet requirements outlined in the SD Well Construction Standards sections 74:02:04:67 and 74:02:04:69. These rules specify how to plug a well depending on the type of well construction, the type of aquifer or aquifers which the well penetrates, and the materials to be used to plug the well. Even though the owner of an abandoned well may plug the well, it is strongly suggested that a SD licensed well driller perform the work due to the varying conditions encountered in plugging an abandoned well. If a well is not plugged properly, ground water contamination may still occur and it is very difficult and expensive to correct the improper plugging of an abandoned well.
Historical Background. Abandoned wells exist throughout South Dakota and tap into every principle aquifer in the state. These are the same aquifers that are relied on today for much of the drinking water used in the state. While the actual number of abandoned wells is not known, it is possible to make some reasonable estimates of the number of abandoned wells. In 1910, South Dakota had approximately 78,000 farms which reached a maximum of 84,300 farms in 1932. Since that time, farm numbers have declined steadily to about 31,700 today. Therefore, South Dakota has lost approximately 52,600 farms that likely had at least one well which may now be abandoned. Aside from the reduction in the number of farmsteads, other factors have also contributed to the creation of abandoned wells such

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======= Instance Index 1805 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are greater or lesser ):

Objects with greater mass have a stronger force of gravity between them.


Jupiter and Saturn are much larger in mass than Earth and Venus, therefore the force of gravity between Jupiter and Saturn is greater or lesser than the force of gravity between Earth and Venus?

Target Text: greater

#### Retrieved Documents ####

Rank: 0
Score: 71.56597
Retrieved Text: Download "Starting from closest to the Sun, name the orbiting planets in order."
2 Chapter 9 Section 2: The Inner Planets The inner planets are referred to as the Terrestrial Planets. The inner planets are denser and rockier than the outer planets. Mercury is closest to the sun, is smaller than the Earth with less surface gravity, has a slower rotation (one rotation takes 59 Earth days), but has a faster revolution around the sun is equal to 88 Earth days. The length of time that it takes an object to rotate once is the objects period of rotation. The time that it takes an object to revolve around the sun once is the objects period of revolution. Venus is Earth s twin planet because Venus is only slightly smaller than Earth (less dense, less mass) and therefore less gravity. Venus has its differences though. Venus rotates the opposite direction that Earth rotates. We call Earth s rotation prograde (counterclockwise as viewed from above the north pole) and Venus s rotation retrograde (clockwise as viewed from the north pole). On Venus the sun rises in the direction that the Earth s sun sets. Venus has the densest atmosphere of the inner planets and it is mostly CO 2 gas. This CO 2 is a greenhouse gas and Venus is therefore has the hottest surface temperature of any planet in the universe. Radar waves have been used to map the surface of Venus and it closely resembles the valleys, plains and mountains of the Earth. Earth is considered

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Score: 68.61248
Retrieved Text: Are you a morning person? If so, and you’re blessed with clear skies, the next several mornings are for you. Just look east, the direction of sunrise. You’ll find the moon sliding by three bright morning planets.
From top to bottom, this planetary lineup showcases Jupiter, Saturn and Venus. Wake up no later than one hour before sunrise to see the spectacle. Think photo opportunity!
On the morning of February 27, 2019, the waning crescent moon closely couples up with the brilliant planet Jupiter as viewed from North America. Elsewhere around the world, the moon is not as close. From the world’s Eastern Hemisphere – Europe, Africa, Asia, Australia and New Zealand – the moon shines to the west of Jupiter on February 27. For all of us, Jupiter and our companion moon will appear very bright and close enough to make waking up early more than worthwhile.
View at EarthSky Community Photos. | Steve Pond in East Grinstead, Sussex, England, caught the waning moon and planets the last time the moon moved through this part of the sky, in late January and early February 2019.
The lighted side of a waning crescent moon points east, the direction of sunrise. The planets Saturn and Venus lie to the east of Jupiter, so the lit face of the moon will point toward the other two planets on the morning of February 27. Notice that the planets and moon make a line on our sky’s dome. This line shows you the whereabouts of the ecliptic, or Earth-sun plane. Since the other planets

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Rank: 2
Score: 66.61884
Retrieved Text: The reason they are considered to be sister, or twin planets, is because they are almost identical in size, and because they both appear to be blue. Their chemical makeup is almost identical as well.
Where is the planet Uranus?
Uranus is the 7th planet from our Sun.\n. \nIt's orbit lies between the orbits of Saturn and Neptune..
Why was the planet uranus named uranus?
What planet is after Uranus?
How far away is Uranus from Neptune?
i want the anwser Comment: Unfortunately there isn't an exact answer. These planets orbit the Sun at different speeds and the distance between them is always changing.
Which is bigger Uranus or Neptune?
Uranus is a little bit bigger if you measure it with Neptune, buteven though Uranus is bigger- Neptune is actually heavier if youmeasure their weight. Which means even if Uranus is bigger, Neptune is heavier.
When were telescopes used to see and to photograph the planets Neptune Uranus and Pluto?
Uranus was discovered by Sir William Herschel in 1781. Neptune was discovered by John Couch Adams in 1846. Pluto was discovered by astronomer Clyde Tombaugh in 1930.
What is the distance between the planet Uranus and Neptune in miles?
Who discovered the planets Jupiter and Saturn and Uranus and Neptune and when?
Why is Uranus a planet?
What is the distance between the planets Uranus and Neptune?
The first planets discovered since ancient times were Uranus and Neptune How were they discovered?
Is the planet Neptune colder than Uranus?
Because Uranus's internal heat is lower than Neptune's -- possibly because it doesn't have a moon as large as Triton providing friction from gravitational

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Retrieved Text: Interplanetary space missions can be launched only at certain times. These launch windows are dependent upon both the relative positions of Earth and the target planets, and the capabilities of the available launch vehicles. The primary launch period for Cassini, based on the alignment of the planets and the capabilities of the Titan IV/Centaur launch vehicle, was in October 1997. The launch boosted the spacecraft into a Venus-Venus-Earth-Jupiter Gravity-Assist (VVEJGA) trajectory toward its final destination of Saturn.
A gravity assist flight path is required because the spacecraft is too heavy to be injected into a direct trajectory to Saturn. Under such a plan it would not acquire enough speed to reach Saturn in a realisitic time scale or have sufficient propellant left over to allow braking for orbit insertion around Saturn.
The principle of gravity assist boosts the spacecraft's velocity because the planet and the spacecraft tug on one another while orbiting the Sun. The spacecraft makes the planet lose some of its orbital momentum. From a planet's point of view, the spacecraft departs with no net energy gain, but from the Sun's point of view, the energy exchange makes a very small change in the planet's solar orbit. That amount of energy, though, benefits the tiny spacecraft substantially. The power comes from the planet's motion about the Sun.
The Moon as seen by Cassini from a distance of about 377 000 km, around the time of the Earth gravity assist on 18 August 1999.
Io transits the face of Jupiter, as seen by Cassini on 1 January 2001, two

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Retrieved Text: The weight (or the mass) of a planet is determined by its gravitational effect on other bodies. Newton's Law of Gravitation states that every bit of matter in the universe attracts every other... How to Calculate Your Weight in Other Planets Calculate your weight by multiplying mass by the gravity on the surface of the planet. Weight = Mass x Surface Gravity Then surface gravity is the gravitational force exert on the surface.
How do scientists measure or calculate the weight of a planet?
Planet Facts There are 8 planets in our solar system, they are Mercury , Venus , Earth , Mars , Jupiter , Saturn , Uranus and Neptune . With the exception of Neptune and Uranus the other 6 planets can be seen unaided and all 8 are visible with a small telescope or binoculars. how to write about things you know nothing about To investigate your hypothesis, find out how much you weigh on other planets using the CERES Solar System Weight Calculator. Then use the Solar System Data Table or books from the school library to see which planets have properties that might affect your weight on other planets.
g p = gravitational acceleration of planet Plug in the values for G, M, m, and r in the equation and solve. Check and see if your answer comes close to the gravitational acceleration in the table of values for that planet.
Weight is the force you feel due to gravity, and 'apparent weight' is the force you feel due to your total acceleration. This means

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Retrieved Text: At about 1000 times larger in volume compared to Earth, Jupiter is the largest planet in our solar system.
In fact, if Jupiter was 50 times larger than it is now, it would be a star on its own. And if you combined all the planets in the solar system, it still wouldn’t be as big as Jupiter.
Other than its tremendous size, Jupiter has tons more superlatives. What are some other facts about Jupiter?
Jupiter spins at an incredible pace. The velocity at Jupiter’s equator is about 28,000 miles per hour, compared to Earth’s 1000 mph.
This means that one day on Jupiter takes a bit less than 10 hours. Because of its fast rotation and heaping size, the coriolis effect is extraordinary in size.
Jupiter’s weather is so extreme that we can see it from space. For example, astronomers have observed an everlasting hurricane ever since we’ve first seen it.
We see this enormous cyclone as a red spot on it because of the Coriolis effect. Also, the Coriolis effect gives Jupiter its banded appearance.
The aurora borealis isn’t unique to Earth. Jupiter has a similar display of lights but of much greater size in comparison.
Electrically charged particles in the magnetosphere and solar radiation from the sun create a magnificent display of aurora borealis on Earth.
Similarly, solar storms cause huge auroras on Jupiter. But they glow much brighter than Earth because Jupiter’s tremendous size gives it more electrical potential.
It’s believed that Jupiter has 79 moons. Only 53 of the moons have names and 26 are awaiting for names.
They were all formed

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Retrieved Text: Jupiter completes a rotation on its axis in about 10 hours.
The solar system has eight planets, which orbit around the sun. Out of the eight planets, six rotate around their axis in the same direction besides revolving around the sun. Jupiter is the fastest spinning planet while Venus is the slowest. Venus takes 243 Earth days to complete one rotation on its axis, making it the slowest of all planets. At the equator, Venus is spinning at the speed of 4.05 miles per hour compared to the Earth which spins at its equator at a speed of 1,037.6 miles an hour. Jupiter completes its rotation on its axis in about 10 hours, and its equator rotates at 28,273 miles an hour.
Jupiter is the 5th planet from the sun and it is the biggest of all planets in the solar system. It is a giant gaseous planet and about 2.5 times the size of all planets combined in the solar system. It spins on its axis in the opposite direction as opposed to most planets. Other gas planets include Saturn, Uranus, and Neptune. Jupiter is believed to have a solid core made of rocks. Like most other planets, Jupiter does not have a defined solid surface. As a result of its rotation, the planet has an oblate spheroid shape having a bulge along the equator. The atmosphere of the planet is divided into different bands that vary with the altitude. At the boundaries are great turbulence and storms and the popular one is the Great Red Spot;

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Retrieved Text: "The discovery of a dark ribbon of weak hydrogen ion emissions that encircles Jupiter has overturned previous thinking about the giant planet's magnetic equator."
The smaller vortices also seem to come in - + pairs, like sun spots, and occasionally resolved in to more concentric 'tubes' .
"The latest data sent back by the Juno and Cassini spacecraft from giant gas planets Jupiter and Saturn have challenged a lot of current theories about how planets in our solar system form and behave.
"The detailed magnetic and gravity data have been "invaluable but also confounding," said David Stevenson from Caltech, who will present an update of both missions this week at the 2019 American Physical Society March Meeting in Boston. He will also participate in a press conference describing the work. Information for logging on to watch and ask questions remotely is included at the end of this news release.
""Although there are puzzles yet to be explained, this is already clarifying some of our ideas about how planets form, how they make magnetic fields and how the winds blow," Stevenson said.
"Cassini orbited Saturn for 13 years before its dramatic final dive into the planet's interior in 2017, while Juno has been orbiting Jupiter for two and a half years.
"Juno's success as a mission to Jupiter is a tribute to innovative design. Its instruments are powered by solar energy alone and protected so as to withstand the fierce radiation environment.
"Stevenson says the inclusion of a microwave sensor on Juno was a good decision.
""Using microwaves to figure out the deep atmosphere was

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Retrieved Text: I'm into the Saturn System but perhaps some time periods have been ascribed to Saturnian times when they were Velikovskian times. One could expect a lot of memories of the old system to be expressed in the later times. If Earth was on an elliptical orbit that took it out to where Jupiter or even Saturn are now, then we could have very confusing Saturn and Jupiter stories in the Velikovsky time period.
If Amun was Venus then Amun-Re would surely be either when Venus approaches the Sun, the near conjunction being a very electrical time for the Earth, or there was a visible Birkeland current connecting Venus and the Sun.
Sorry about the Mercury, not the Moon, coming out of Mars. Still think that is very unlikely. But where did the Moon come from then ? Born from Jupiter. As I wrote before, the Moon is in equilibrium with it's plasma environment and this suggests the Moon was in this environment for a long time, so not born from Jupiter.
* Aten, I think Cardona, Talbott et al have developed the most plausible chronology of ancient history, which involves primarily the Saturn System. You seem to ignore the Saturn influence. Have you bothered to read about the Saturn Configuration at all? Much of what you say seems to contradict the Saturn theory and thus seems largely wrong.
What I think the problem is that Gary and maybe others have deciphered the Egyptian evidence and found references to Saturn and Jupiter that clearly have nothing to do with a Saturn

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Retrieved Text: With eight other planets, dozens of moons, thousands of minor planets, myriads of comets and meteoroids and in addition interplanetary dust which circle around a central star named the Sun, Venus is a member of a collection of celestial objects which is called the Solar System. It extends over 12,000 million kilometres in space. Counting from the Sun, Venus is the second planet. Venus' orbit is the most circular of any planet, with an eccentricity of less than 1%. The dominant body is the Sun which accounts for more than 99% of the mass of the Solar System. Our Solar System was once regarded as the largest and central part of the Universe. But today we know it is just a tiny speck compared with the rest of the Universe.
Venus belongs to the group of planets from Mercury to Saturn that are bright and easily seen by the naked eye, and well known to the ancients. The three most distant planets - Uranus, Neptune, and Pluto - were discovered after the invention of the telescope in 1609. Uranus and Neptune can be seen with a pair of binoculars, but to detect Pluto requires a moderately-sized telescope.
Compared to the Sun, Venus and the other planets are relatively cold and only visible by reflected sunlight. To observers on Earth, both Venus and Mercury show phases like the Moon, because their orbits lie inside the Earth's orbit. So Venus and Mercury are called inferior planets. On the other hand, Mars, Jupiter, Saturn, Uranus and Neptune lie outside, so they

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Retrieved Text: While we have been learning about the nine planets in our solar system since childhood, of late there has been a bit of confusion about the number of planets with Pluto being knocked off the list.
Solar system is a minute component of the vast universe which was formed billions of years ago. It consists of the Sun and several celestial bodies revolving around it. These include planets (and their satellites), asteroids, meteoroids, etc. Until 2006 the number of planets in our solar system was nine, but the exclusion of Pluto has left us with only eight planets.
The Sun is the center of our solar system and has eight planets orbiting it. These include―starting from the nearest to the Sun―Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Initially considered a planet, Pluto was officially declared a dwarf planet by the International Astronomical Union (IAU) in 2006, thus bringing the number of planets down to eight. Let's have a brief look at each of these planets.
Mercury: Mercury is the smallest planet in our solar system. At 3031.670 miles, its diameter is 38 percent the diameter of the Earth. It has extreme climate with temperature ranging between −180 to 430 °C. It is located at a distance of 0.39 AU. On the basis of information sent by Mariner 10 spacecraft, scientists suspect that some volcanic activity is occurring on Mercury.
Venus: Venus is a small, rocky planet, typically characterized by a thick blanket of yellowish clouds of sulfuric acid. With a diameter of 7521.076 miles, Venus is bigger than

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Retrieved Text: The year was 2565: Humans had colonized most of their solar system. There were orbiting habitats around Venus, Earth, Mars, Jupiter, Neptune, and in the rings of a Saturn and Uranus. Diamonds were mined in the heavy gravity of Uranus and shipped back to Earth while fossil fuels where found on Jupiter and Saturn. Colonies had formed on most of the moons of the gas giants and economy was booming for rich businessmen. In the later years before colonization, the peoples of earth decided that they would share the wealth. However, it was usually the poor who were sent to be colonists on some worlds. One such place was the floating cities of Neptune.

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Retrieved Text: I recently realized that when I say “ice,” most people don’t understand what I mean.
I am a planetary scientist, and I have studied (among other things) the ice giants of our solar system: Uranus and Neptune. What do you think “ice giant” means? It does not mean that Uranus and Neptune have crystalline water-ice interiors. Much like other potentially misleading words “rock,” “sand,” and “haze,” the word “ice” has a different and particular meaning to planetary scientists.
Only Voyager 2 has visited the ice giants, Uranus (left) in 1986 and Neptune (right) in 1989. These Voyager portraits are newly reprocessed to show the 2 planets at correct relative size and color. Since Voyager, planetary astronomers have studied the ice giants from Earth and have seen their faces change.
Uranus and Neptune, like all the other planets, formed within the solar nebula, a disk of material surrounding our newborn star. Some nebula materials -- silicate minerals or iron, for instance -- were in the solid phase almost everywhere in the nebula, except very close to the young Sun. Other materials, such as hydrogen and helium, were gaseous at any distance from the Sun. But some materials, like methane, ammonia, and water, were gases at the higher temperatures close to the Sun, and snowy solids farther away.
Close to the Sun, only silicates and metals could condense. Farther from the Sun, more volatile components -- chiefly water -- could condense, coating dusty particles with ices.
The behavior of ices in the early solar system explains the difference between the giant planets Jupiter,

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Retrieved Text: A Wikibookian suggests that this book or chapter be merged into Solar System.
From our small world we have gazed upon the cosmic ocean for thousands of years. Ancient astronomers observed points of light that appeared to move among the stars. They called these objects planets, meaning wanderers, and named them after Roman deities -- Jupiter, king of the gods; Mars, the god of war; Mercury, messenger of the gods; Venus, the goddess of love and beauty; and Saturn, father of Jupiter and god of agriculture. The stargazers also observed comets with sparkling tails, and meteors -- or shooting stars apparently falling from the sky.
Since the invention of the telescope, three more planets have been discovered in our solar system: Uranus (1781), Neptune (1846) and Pluto (1930). Pluto was reclassified as a dwarf planet in 2006. In addition, our solar system is populated by thousands of small bodies such as asteroids and comets. Most of the asteroids orbit in a region between the orbits of Mars and Jupiter, while the home of comets lies far beyond the orbit of Pluto, in the Oort Cloud.
The four planets closest to the sun -- Mercury, Venus, Earth, and Mars -- are called the terrestrial planets because they have solid rocky surfaces. The four large planets beyond the orbit of Mars -- Jupiter, Saturn, Uranus, and Neptune -- are called gas giants. Beyond Neptune, on the edge of the Kuiper Belt, tiny, distant, dwarf planet Pluto has a solid but icier surface than the terrestrial planets.
Nearly every planet -- and some

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Retrieved Text: A conjunction of Mercury and Venus appears above the Moon, as viewed from the Paranal Observatory in northern Chile.
When two objects always appear close to the ecliptic—such as two planets, the Moon and a planet, or the Sun and a planet—this fact implies an apparent close approach between the objects as seen on the sky. A related word, appulse, is the minimum apparent separation on the sky of two astronomical objects.
Conjunctions involve either two objects in the Solar System or one object in the Solar System and a more distant object, such as a star. A conjunction is an apparent phenomenon caused by the observer's perspective: the two objects involved are not actually close to one another in space. Conjunctions between two bright objects close to the ecliptic, such as two bright planets, can be seen with the naked eye.
A conjunction of Mars and Jupiter in the morning of 1 May 2011, when, about an hour before sunrise, five of our Solar System's eight planets and the Moon could be seen from Cerro Paranal, Chile.
More generally, in the particular case of two planets, it means that they merely have the same right ascension (and hence the same hour angle). This is called conjunction in right ascension. However, there is also the term conjunction in ecliptic longitude. At such conjunction both objects have the same ecliptic longitude. Conjunction in right ascension and conjunction in ecliptic longitude do not normally take place at the same time, but in most cases nearly at the same time. However, at triple

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Retrieved Text: Early this month in the twilight just after sunset look for Venus still bright in the west. Then look a little more and not far away you will find another object shining without twinkling. That will be the planet Saturn. Both will have disappeared into the sunset glow by the end of the month.
Planets appear to move amongst the fixed stars and so attracted the attention of the early civilisations. Saturn was named by the Romans for the father of the king of the gods, Jupiter. This planet was the most distant known to the ancients and travelled through the stars more slowly than any other planet they watched. Thus it seemed logical to name it for an elderly and presumably slow-moving god. The planet speeding fastest was called Mercury – the messenger of the gods whose sandals were winged. Venus is the brightest and most beautiful planet visible from Earth and not surprisingly was named for the goddess of beauty and love.
As you will see, Venus is far more brilliant than Saturn. Indeed you may not be able to make out the latter until the twilight begins to darken. Does this mean that Venus is bigger than Saturn? By no means – it is just an optical effect of distance. Just as a candle in your hand would seem brighter than a searchlight miles away so nearby but tiny Venus outshines gigantic but distant Saturn. Both shine by reflected sunlight.
In between Earth and Saturn lie the orbits of Mars, the asteroids and Jupiter. It is

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Retrieved Text: Bollinger, C.J. (1952). A 44.77 year Jupiter-Earth-Venus configuration Sun-tide period in solar-climate cycles. Academy of Science for 1952 – Proceedings of the Oklahoma 307-311.
who illustrated the ~22 year JEV cycle over 60 years ago — see the configurations illustrated in Table 1 on p.308.
The dominant planetary gravitational force acting upon the outer convective layer of the Sun is that produced by Jupiter.
Other than Jupiter, the two planets that apply the greatest tidal forces upon the outer convective layer of the Sun are Venus and the Earth.
Periodic alignments of Venus and the Earth, on the same or opposite sides of the Sun once every 0.7997 sidereal Earth years, produces temporary tidal bulges on opposite sides of the Sun's surface layers (red ellipse in the schematic diagram above).
Whenever these temporary tidal-bulges occur, Jupiter’s gravitational force tugs upon these tidally-induced asymmetries and either slows down or speed-up the rotation rate of plasma near the base of the convective layers of the Sun.
It is proposed that it is the resultant variations in the rotation rate of the Sun’s lower convective layer, produced by the planetary tidal torquing of Venus, the Earth and Jupiter, that modulate the Babcock-Leighton solar dynamo. Hence, we claim that it is this modulation mechanism that is responsible for the observed long-term changes in the overall level of solar activity. In addition, this mechanism may be responsible for the torsional oscillations that are observed in the Sun's convective layer, as well.
It naturally produces a net increase in the rate of rotation of the outer layers of the

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Retrieved Text: Here's another thought: Try our best not to use the DailyMail (UK) as a source or citation for anything you ever do again in your life, or at least not here in the TB Forum. The reason is, it has a terrible global reputation for fear-mongering, exaggeration and playing to the crowds' lowest imaginable taste. Using this source, no matter how impressive in it's immediate appearance, will do more to damage your case and your reputation - right out of the starting gate! - than any statement or remark you might subsequently make in connection with that source or citation.
Re: Does gravity make the core compact?
Although this is not entirely related to the opening post, the gravity mapping just underlines that the gravity constant (G) is misguided and would have implications on any gravity driven model. The question whether it may be related to charge is a good one, and Wallace Thornhill has brought up the very same issue. I really recommend the DVD set of his seminar at SIS this summer, where he summarized the issues of current cosmology and gravity, as well as explaining Plasma Cosmology and The Electric Universe.
Select "Other Purchases" and type "W.Thornhill Electric Universe DVDs"
But I feel that clever visual representation should help intellectually honest ones to intuitively realize this: if our planet formed as a result of a gravity-driven coalescing of a spinning cloud of matter, it wouldn't have resulted in a truly round planet. Thus gravity is NOT be the primary driving force behind planet formation.
That's my non-scientist take

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Retrieved Text: Which Planet Has More Rings: Jupiter or Saturn?
Scientists still have a lot to learn about the vast, fascinating, mysterious zone around Earth they refer to as space. Space research discovers new facts about the cosmos all the time. One thing they do know is that there are eight primary planets in our solar system: Earth, Saturn, Jupiter, Uranus, Neptune, Mercury, Venus and Mars. (Pluto was demoted to a dwarf planet.) From Earth, you can see any of the other seven planets through a telescope. Four of these planets are known to have rings, but not all of the rings are made equally – Saturn stands out for having the largest and most impressive set.
Which Planet Has the Largest Set of Rings?
While all the so-called "giant" planets in our solar system – Saturn, Jupiter, Uranus and Neptune – have rings, none of them are as spectacular as Saturn's. Neptune has six known rings, and Uranus has 13 known rings. While scientists don't know for sure how many rings Saturn has, they believe it's in the region of 500 to 1,000. By contrast, only four rings have been identified around Jupiter.
Mercury, Venus and Mars have no rings.
Jupiter is named after the Roman god of the sky and thunder and is the fifth planet from the Sun. It is made of gas and covered in swirling clouds of ammonia and water. Although it doesn't have a solid surface, it may have a solid inner core about as big as Earth. Jupiter is famous for its Great Red Spot, a

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Retrieved Text: As Earth and the various other planets and other bodies of the solar system travel on their respective orbits around the sun, it happens from time to time that, from our vantage point here on Earth, two (sometimes more) of the other planets (and/or other bodies) will lie along the same line of sight and appear close to each other in the sky. This apparent nearness to each other is simply an effect of viewing perspective, as the respective planets are usually at vastly different distances from us.
Such an event is usually called a conjunction.
Several nights last week featured one such conjunction taking place in our evening southern sky, slightly east of the head of the prominent constellation Scorpius. Shining fairly brightly slightly to the north of the bright star Antares is the red planet, Mars, and about 4 degrees – eight times the apparent diameter of the moon – to Mars’ north is the somewhat dimmer planet Saturn.
The fact that this conjunction is simply due to viewing perspective is underscored by the fact that, while Mars is currently just under 80 million miles from Earth, Saturn is over eleven times farther away, current distance just over 910 million miles.
Conjunctions such as these are always transitory. Both Mars and Saturn are traveling eastward relative to Scorpius, although Mars, being much closer, will rather rapidly leave Saturn and Antares behind over the next few weeks, while Saturn, being much more distant, plods along much more slowly.
An even more dramatic conjunction takes place this coming week, and involves

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Retrieved Text: We recently published an article naming Jupiter “the best planet.” As everyone knows, Saturn is the best planet. We regret the error.
Last October, The Atlantic published, “Jupiter Is the Best Planet,” an article by Adrienne LaFrance. As editor of that article, I must take responsibility for the way it misled readers. In cases like this, we usually append a correction to the original article, but here the error is so grave that a freestanding editorial mea culpa is required. Jupiter is not, as LaFrance asserts, the best planet.
That honor rightly belongs to Saturn.
LaFrance was right to choose from the outer planets. With the exception of Earth (off-limits in this exercise) the inner planets are a bore. Mercury is a tiny thing, sun-blasted and crater-pocked, more moon than planet. Venus glows lovely in the sky, but its atmosphere is a hellish, sulfur-smelling place, with temperatures hot enough to melt lead. Probes sent to its surface survive less than an hour before succumbing to the extreme conditions. Venus is useful only as a cautionary tale about the runaway greenhouse effect.
We are told that Mars was once a blue marble, coated in oceans and swirling white clouds. But today it’s a rusting, dried-out husk, stripped of its atmosphere. The ubiquity of Mars in pop culture has everything to do with its proximity to Earth, and nothing to do with the planet itself.
Jupiter—or “good old Jupe” as LaFrance sweetly calls it—is a fine planet. It is, as she notes, the largest in our solar system. But there is something a

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Retrieved Text: NASA has revealed its final plans to crash the Cassini probe into Saturn next year.
Cassini–Huygens, to give the craft its full name, launched in 1997 and skipped past Venus twice and Earth once for some gravity-assisted acceleration action. It then grazed Asteroid 2685 Masursky, used Jupiter for acceleration and arrived at at Saturn on July 1st, 2004.
It's orbited ever since, clocking up 243 orbits, discovering ten moons and sending home 599GB of data that helped to fuel 3,616 scientific papers.
But the probe is now running out of fuel meaning NASA won't be able to control Cassini for much longer. It's therefore been decided to send the craft straight into Saturn because of the risk the craft may carry a terrestrial microbe that could damage the ecosystems it's speculated may exist on the gas giant's moons.
NASA's therefore started the year-until-death countdown for the probe, which will meet its fate on September 15th, 2017.
Cassini has a busy year to get through before dying. At present it's using Titan's gravity to raise its orbital tilt with respect to Saturn's equator and rings. From that position Cassini will be able to visit Saturn's “F rings” “kinked and braided”. Cassini's not had a good look at the F rings since 2004 and then only managed to see one side. This time around – or times, because the mission plans 20 orbits – the craft will get a very good look at the rings from a distance of just 7,800 kilometers.
The probe will then sneak between Saturn and the rings 22 times,

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Retrieved Text: Two bombings over the past two days in Volgograd, Russia, have killed over 30. Because of the astrology, I warned of the possibility of post-Christmas violence here. This chart is for midnight between the first and second bombing: the same configurations apply to both events. Regular readers know the drill: mass-murderers (including many politicians) and mass-murder events have charts that conform to the Bloodbath Formula.
1. Pallas trine Pluto and contraparallel Jupiter: ethics compromised.
2. Venus decile Neptune and ruled by Saturn which is quindecile South Node: Venus (property rights including rights to one's own body) liquefied.
3. Pluto septile Saturn, ruler of Venus: Destruction (Pluto) of property including human bodies (Venus).
4. Pluto conjunct Sun. Days of death, as it were.
5. Mercury prominent -- conjunct Sun.
I expect more violence between now and when Pallas is clear of Pluto and Jupiter. Pallas represents, among other things, the libertarian non-aggression principle. When she or her sign ruler is corrupted by Pluto, blocked by Jupiter, and/or drained by the South Node, evil is afoot. When the other factors in the Bloodbath Formula also come into play, we see lethal and senseless violence.

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Retrieved Text: ကမ္ဘာ့ဒြပ်ထု၁၀ထက်ကျော်လျှင် ဂြိုဟ်ဘီလူများဟုသတ်မှတ်သည်။  Lower-mass gassy planets are sometimes called "gas dwarfs".
Objects large enough to start deuterium fusion (above 13 Jupiter masses for solar composition) are called brown dwarfs and these occupy the mass range between that of large gas giants and the lowest-mass stars. The 13 Jupiter mass (MJ) cutoff is a rule of thumb rather than something of precise physical significance. Larger objects will burn most of their deuterium and smaller ones will burn only a little, and the Template:Jupiter mass value is somewhere in between. The amount of deuterium burnt depends not only on mass but also on the composition of the planet, especially on the amount of helium and deuterium present. The Extrasolar Planets Encyclopaedia includes objects up to 25 Jupiter masses, and the Exoplanet Data Explorer up to 24 Jupiter masses.
ဓာတ်ငွေ့ဂြိုဟ်ဘီလူးများသည် အလေးချိန်များပြားပြီး ဟိုက်ဒရိုဂျင်နှင့်ဟီလီယမ်ဓာတ်ငွေ့များပါသည့် ထူထပ်သောလေထုရှိကြသည်။ They may have a dense molten core of rocky elements or the core may have completely dissolved and dispersed throughout the planet if the planet is hot enough. The hydrogen and helium in "traditional" gas giants like Jupiter and Saturn constitutes most of the planet, whereas the hydrogen/helium only makes up an outer envelope on Uranus and Neptune which are sometimes called ice giants, as they are mostly composed of water, ammonia, and methane molten ices.
Among extrasolar planets, Hot Jupiters are gas giants that orbit very close to their stars and thus have a very high surface temperature. Hot Jupiters are currently the most common form of extrasolar planet known, perhaps due to the relative ease of detecting

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Retrieved Text: 6. Why do we have “Lunar” calendar when Jupiter and Saturn are bigger than moon?
Answer: With a simple view of Newton’s theory of Gravity, the force of pull is directly proportion to the sizes, but it is also inversely proportional to the square of the distance between two objects. Hence the farther objects like Jupiter & Saturn, even though they are heavier have lot less influence due to their distance.
As mentioned to an earlier question, a father, a mother, a teacher or a role model (friend) who is close by has a big effect compared to others who are not nearby (like the effect of an officer of a ministry or some arbitrary company’s project's manager)!
Let us consider another aspect. The moon is approximately at a distance of 108 times its diameter. The sun is approximately at a distance of 108 times its diameter. That is the reason that we have total solar eclipse most of the times. At times, when sun is nearer (earth is at perihelion and sun appears a bit bigger) & moon is farther than average (moon is at apogee and appears a bit smaller), then we have “annular” eclipse (ring of sun seen around moon).
Jupiter is at a distance much more than 108 times its diameter – hence it looks so small (otherwise it would also look the size of the sun / moon). Obviously this leads to the conclusion that it has less effect compared to sun / moon! Hence, a “Jupiter” based calendar makes less sense (at least to

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Retrieved Text: The Solar System was formed approximately 4.6 billion years ago and consists of the Sun, planets, dwarf planets and other astronomical objects bound in its orbit. The formation was caused by the collapse of a giant molecular cloud, the mass at the centre collecting to form the Sun and a flat disk of dust around it which the planets and other bodies would eventually be formed from.
99.86% of the system’s mass is found in the Sun and the majority of the remaining 0.14% is contained within the solar system’s eight planets.
The four smaller inner planets, also known as the “terrestrial planets” (Mercury, Venus, Earth and Mars), are primarily composed of rock and metal.
The four outer planets, also known as the “Jovian planets” (Jupiter, Saturn, Uranus and Neptune), are substantially larger and more massive than the inner planets.
The two innermost gas giants, Jupiter and Saturn, are the larger of the four and are composed mainly of hydrogen and helium.
The two outermost gas giants, Uranus and Neptune, are composed largely of ices, (water, ammonia and methane) and are sometimes also referred to as the “ice giants“.
Other objects of note in the Solar System are the dwarf planets (Ceres, Pluto, Haumea, Makemake & Eris), moons, asteroids, the asteroid belt, comets and the Kuiper belt.
Compared with the billions of other stars in the universe, the sun is unremarkable. It holds the solar system together and pours life-giving light, heat and energy on Earth.
The first planet in our system was settled in 2034 by fearless men and women not afraid of

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Retrieved Text: Another related to the Electric Universe theory on the Solar System Cosmogony is the Velikovsky / Ackerman scenario or shortened to the V/A Scenario.
These are John Ackerman's theories based on the works of Immanuel Velikovsky, starting with Velikovsky's Worlds in Collision. It would be suggested the V/A model is not accepted EU theory but is partly based or uses ideas from it.
The basic idea (this is my summary so may be wrong) for the formation of the previous and present solar system involves only the giant planets forming first but they are ice giants not gas giants. Then a wandering giant planet is captured by our solar system and impacts on Jupiter causing solar system and planetary chaos. The rocky planets were born out of this massive Jupiter and other impacts on the ice giants.
John Ackerman obviously explains it in more detail in his website Firmament and Chaos, his blog and the article The Cosmogony of the Solar System which the quotes below are taken from.
In the proposed cosmogony, the solar system began with the accretion of the giant ice planets, Jupiter, Saturn, Uranus and Neptune in their current orbits.
... the age of the Galilean satellites and most of the other Jovian satellites is less than 6,000 years. They resulted from the same high energy impact on Jupiter which produced the GRS, the clouds, the rings, and the temperature excess. The Galilean moons formed in their current resonant orbits in the last six thousand years. The proto-Galilean satellites formed immediately from material which was ejected into

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Retrieved Text: How are the rings of planets formed and what are they made out of?
The rings around planets like Jupiter and Saturn (yes Jupiter has rings!) are made up of bits of ice and rock.
They form when asteroids,comets, or any other large objects pass too close to the planet and are torn apart by the planet's gravity. There is a point around the planets called the Roche Limit. This is the point where gravity will tear apart an incoming object, and prevent the particles from re-accreting back into a larger object.
Essentially, rings are just thousands of tiny moonlets that orbit a planet and don't clump back into larger objects.
There is a problem, however, if the debris orbiting a planet orbits too closely. Because gravitational force varies with distance, the different accelerations between two points at different distances from a massive object create a tidal force that has a stretching effect on nearby objects. This force from the Sun and Moon creates tides on opposite sides of the Earth, for example. When the tidal force is large enough, it overcomes the gravitational forces trying to bring individual particles together. Within a given distance from a planet, called its 'Roche Limit', tidal forces prevent debris from aggregating into larger bodies.
Planetary rings, then, consist of millions of separate small rock and ice particles, each maintaining their own orbit around the host planet. From a distance, these small orbiting particles only APPEAR to be a continuous, solid ring.

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Retrieved Text: Monday evening August 13th the thin 2.5-day young waxing crescent Moon will be about 10o from the inner planet Venus, and about 8o from the Dwarf Planet Ceres. However at 8th magnitude Ceres will be not be naked-eye visible, but Venus at a -4.6 apparent magnitude will be hard to miss!
And spread out from west to east are the planets Jupiter, Saturn, and Mars.
This entry was posted in Astronomy, Astrophotography, Classroom, Earth and Space, Jupiter, Lesson Plan, Mars, Moon, Observing, Planets, Saturn, Venus and tagged 7x50 binoculars, astronomy, astrophotography, conjunction, crescent Moon, jupiter, mars, moon, observing, orbit around the sun, planets, saturn, science, the Moon, Venus, waxing crescent moon by Bob Riddle. Bookmark the permalink.

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Retrieved Text: The number of kidney diseases has increased now a days. Due to modern style of living and lack of exercise common man is suffering from diabetes mellitus, high blood pressure, failure of kidney and obesity etc. He is taking excess drugs to get relief from them. The excess drugs and allopathic drugs have side effects. He is suffering from kidney troubles which end in failure of kidney or need transplantation of kidney.
The kidney is ruled by 7th house and 7th lord. Any affliction to 7th house or 7th lord causes kidney troubles. Jupiter and Moon are the karaka of kidney disease. Venus is karaka of the 7th house and Libra sign rules the 7th house of natural zodiac. The Libra sign is ruled by Chitra, Swati and Vishakha nakshtra. The Chitra III and IV pada rule the ureter of the kidney and bladder. If the lord of these nakshtra, Mars, Rahu, and Jupiter respectively are afflicted, the native suffers from kidney troubles. If there is influence of Saturn on sign of Venus, nakshtra of Jupiter on the 7th house, the native needs transplantation of kidney. If Mars or Saturn has astrological relations with Rahu, the chronic diseases are caused.
Libra sign rules over kidney, loin, uterus, lumber region, vertebrae, prostate, and pineal gland.
If Libra is afflicted the native suffers from backache, pain in urinary track, venereal disease, The sign Virgo is 12th to Libra, so indicates loss of functions of kidney.
When the above house and lord and karakas are influenced by 6th house or 6th lord or

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Input Text: Read the passage below and choose the right answer to the following question (choices are Sally or Sue ):

Electrons at lower energy levels, which are closer to the nucleus, have less energy.


Sally has an electron. Sue has an electron that is closer to the nucleus. Whose electron has lower energy Sally or Sue?

Target Text: Sue

#### Retrieved Documents ####

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Retrieved Text: The Aufbau model lets us take an atom and make predictions about its properties. All we need to know is how many protons it has (and how many electrons, which is the same as the number of protons for a neutral atom). We can predict the properties of the atom based on our vague idea of where its electrons are and, more importantly, the energy of those electrons.
How electrons fill in their positions around an atom is called the Aufbau Process (German: "building-up" process). The Aufbau Process is all about keeping electrons at their lowest possible energy and is the direct result of the Pauli Exclusion Principle. A corollary of Coulomb's law is that the energy of an electron is affected by attractive and repulsive forces. The closer an electron to the nucleus, the lower its energy. The closer an electron is to another electron, the higher its energy.
Of course, a basic principle of thermodynamics is that a system will proceed to the lowest energy possible. That means, if an atom has only one electron, the electron will have quantum numbers that place it at the lowest possible energy. It will be as close as possible to the positive nucleus.
If an atom has a second electron, it will also be as close as possible to the nucleus. It could have the same quantum numbers as the first electron, except for spin. There is a trade-off, of course, because those two electrons will be close enough to repel each other. However, if it is a choice between

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Retrieved Text: `●` Shapes of Atomic Orbitals.
`●` Nodal surface or Node .
`=>` According to Max Born, the square of wave function(i.e, ` psi^2`) at a point gives the probability density of the electron at that point. Fig 2.12(b).
`=>` For 1s probability density is maximum at the nucleus and it decreases sharply as we move away from it. But for 2s orbital the probability density first decreases sharply and again starts increasing. After reaching a maxima it decreases again and approaches zero as the value of r further increases.
The region where the probability density function reaches to zero.
This gives fairly good representation of the shapes of the orbitals.
In this, a boundary surface or contour surface is drawn in space for an orbital on which the value `|psi|^2 ` is constant.
Definition : For a given orbital, only that boundary surface diagram of constant probability density is taken which encloses a region or volume in which the probability of finding the electron is `90%`. fig [2.13 (b)].
Note : - We do not draw boundary surface diagram of `100%` probability because ` psi^2` has always some value at any finite distance from the nuclues, so it is not possible to draw a boundary surface diagram of a rigid size of `100%` probability.
For `s`-orbital, boundary surface diagram is spherical in shape. i.e the probability of finding the electron in all direction is equal.
For `p`-orbital (Fig 2.14), the boundary surface diagram is not spherical. But it has two lobes which are on either side of the plane passing through the nucleus. At this plane,

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Retrieved Text: As quantum mechanics theory posits, since electrons are negatively charged they are attracted to nuclear protons by a force called "binding energy." Each "n" orbit possesses its own binding energy value expressed in "electron volts." The closer the electron is to a hydrogen atom's proton nucleus, the greater the binding energy. As an electron jumps from an orbit with a lower binding energy to an orbit with greater energy (n2 to n1 for example), it emits light at a specific ultraviolet frequency. Light from the n2 to n1 jump corresponds to 121.6 nanometers and is called "Lyman-alpha" radiation, named for Theodore Lyman, who first discovered it in 1906.

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Retrieved Text: Following the work of Ernest Rutherford and his colleagues in the early twentieth century, the picture of atoms consisting of tiny dense nuclei surrounded by lighter and even tinier electrons continually moving about the nucleus was well established. This picture was called the planetary model, since it pictured the atom as a miniature “solar system” with the electrons orbiting the nucleus like planets orbiting the sun. The simplest atom is hydrogen, consisting of a single proton as the nucleus about which a single electron moves. The electrostatic force attracting the electron to the proton depends only on the distance between the two particles. The electrostatic force has the same form as the gravitational force between two mass particles except that the electrostatic force depends on the magnitudes of the charges on the particles (+1 for the proton and −1 for the electron) instead of the magnitudes of the particle masses that govern the gravitational force. Since forces can be derived from potentials, it is convenient to work with potentials instead, since they are forms of energy. The electrostatic potential is also called the Coulomb potential. Because the electrostatic potential has the same form as the gravitational potential, according to classical mechanics, the equations of motion should be similar, with the electron moving around the nucleus in circular or elliptical orbits (hence the label “planetary” model of the atom). Potentials of the form V(r) that depend only on the radial distance r are known as central potentials. Central potentials have spherical symmetry, and so rather than specifying

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Retrieved Text: principle that relates to electron energies.
separation for two atoms or ions.
separation and the bonding energy.
hydrogen, and van der Waals bonds.
protons and neutrons within the nucleus.
atomic masses, which are called isotopes.
 Electrons are assumed to revolve around the atomic nucleus in discrete orbitals, and the position of any particular electron is more or less well defined in terms of its orbital.
 Another important quantum-mechanical principle stipulates that the energies of electrons are quantized; that is, electrons are permitted to have only specific values of energy. An electron may change energy, but in doing so it must make a quantum jump either to an allowed higher energy (with absorption of energy) or to a lower energy (with emission of energy). Often, it is convenient to think of these allowed electron energies as being associated with energy levels or states. These states do not vary continuously with energy; that is, adjacent states are separated by finite energies.
- values of energy that are permitted for electrons.
 Bohr model was eventually found to have some significant limitations because of its inability to explain several phenomena involving electrons. A resolution was reached with a wave- mechanical model, in which the electron is considered to exhibit both wavelike and particle-like characteristics. With this model, an electron is no longer treated as a particle moving in a discrete orbital; but rather, position is considered to be the probability of an electron’s being at various locations around the nucleus. In other words, position is described by a probability distribution or electron cloud.
 Using wave mechanics,

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Retrieved Text: An orbital is a region in space where there is a high probability of finding electron.
A wave function represents an electron is the product of two parts, a radial part and an angular part. The square of the radial part of the wave function indicate the probability of finding the electron at any distance r from the nucleus. The square of the angular part of the wave function gives the probability of finding an electron in a particular direction from the nucleus. The radial dependence and angular dependence of wave function taken together, tell us that a three dimensional standing electron wave (orbital) can be picture to have size, shape, and an orientation of an orbital.
Principal Quantum Number ( n ).
The Orbital angular momentum quantum Number or Azimuthal Quantum Number ( l ).
The Magnetic Quantum Number (ml ).
The Principal quantum Number(n) is of primary importance in the determining the size and hence the energy of an electron.
For hydrogen the energy is fixed by the value of n. In other multi electron atom, the energy of each electron depends on the value of the principal quantum number of the electron. As the value of n increases the radius (nucleus electron separation increases that is the size of the orbital increases).
The energy also raised, n is always an integer and can assume the value,1,2,3,4.... but not zero.
The general geometric shapes of an electron wave (Orbital) is described by the Azimuthal Quantum Number.
This quantum number related to for the electron in that state.
Therefore an electron having principal quantum number

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Retrieved Text: You will place electrons in the appropriate energy levels outside of an atom.
Explain that an atoms outermost electrons are responsible for an elements reactivity.
Identify the electron arrangement within atomic energy levels.
Explain that an electrons energy is related to its distance from the nucleus.
An atom has three subatomic particles: the proton, the neutron, and the electron. The proton has a positive charge, is located in the nucleus and is responsible for an atom's identity. The number of protons does not change in an element, and is equal to the atomic number on the periodic table. Neutrons are also located in the nucleus, but have no charge.
The electrons are located outside the nucleus, and have a negative charge. The electrons will arrange themselves into specific energy levels, starting with the level closest to the nucleus. Each energy level has a maximum number of electrons it can hold: two in the first, eight in the second, 18 in the third and 32 in the fourth. As the distance of the energy level from the nucleus increases, so does the energy the electrons contain.
The arrangement of the electrons in their energy levels is called the "electron configuration." In a neutral atom, the number of electrons will be the same as the atomic number, or number of protons. For learners to place the electrons in the appropriate energy level, they should identify the atomic number, and start placing the electrons in energy levels, the closest to the nucleus first. Once the energy level has its maximum number of electrons, they should

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Retrieved Text: And in my mind, something like this provides a much better understanding of how things work - much better than: "an equation [or a principle] says so" ..
I vote de Broglie. He seems to have been sidelined and never made any further significant contributions to physics. It would be a testament to his foresight and give him more significance in the history of physics. I have for years thought quantum mechanics lacking clarity. No wonder quantum gravity has eluded physics for 100 years.
From the previously mentioned article.
"The experiments began a decade ago, when Yves Couder and colleagues at Paris Diderot University discovered that vibrating a silicon oil bath up and down at a particular frequency can induce a droplet to bounce along the surface. The droplet’s path, they found, was guided by the slanted contours of the liquid’s surface generated from the droplet’s own bounces — a mutual particle-wave interaction analogous to de Broglie’s pilot-wave concept."
In a modified form this describes gravity.
You can't really use an electron to release energy from a nucleus.
- For one thing, the electron very rarely interacts with the nucleus of an atom.
- And in those rare instances where an interaction does occur, much of the energy is carried away by the ghostly neutrino, which we can't capture as an energy source.
Combining two deuterium nuclei (or a dueterium & a tritium) to make a Helium nucleus does release a usable amount of energy.
- However, the wavelength of an electron is too long to draw the two nuclei together close enough for a

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Retrieved Text: Therefore,Ne has the most positive electron affinity value Br and has the most negative electron affinity value among the given elements. Potassium has a more positive electron affinity value than phosphorous, since electron affinity decreases from top to bottom and increases from left to right in periodic the table. how to find last action on mac The electron affinity of an element is a measure of that element’s tendency to act as an oxidizing agent (an electron acceptor) and is generally related to the nature of the chemical bonds the element forms with other elements.
Which has the more negative electron affinity br or br?
The electron affinity is a measure of the attraction between the incoming electron and the nucleus - the stronger the attraction, the more energy is released. The factors which affect this attraction are exactly the same as those relating to ionisation energies - nuclear charge, distance and screening.

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Retrieved Text: If electrons are held in orbit by electromagnetic attraction to nuclei, shouldn't electrons crashing into the nucleus be a common event? If so, why have I never heard about this?
Today we have abandoned the solar system model of the atom in favor of the Schr&#246;dinger model: electrons are standing waves distributed through the spherical volume of the atom. Nevertheless, we still understand electronic energy levels as being quantized. Electrons are not permitted to fall into the nucleus because this would involve a violation of quantization.
Finding the electron in the nucleus would also be a violation of the Uncertainty Relation: we would know the electron's position and momentum simultaneously! In fact, the electron's velocity can be approximated by solving the expression for the uncertainty in velocity, using the electron's rest mass and the mean distance of the electron from the nucleus (which can be calculated from the expression for the atomic orbital -- a wave equation! -- in which the electron is located).
Electrons are inherently fuzzy particles, especially when they are in atoms -- and the "fuzz" is on the order of the size of the atom. This means that, while the electron has a certain probability of being "in" the nucleus, the probability can never be 100%.
It is not a common event, but something like that does happen: electron capture (http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/radact2.html#c3).
Not really. It would be allowed in the nucleus but for the Uncertainty Principle. However, because of Heisenberg, it isn't.
Actually, the way it's worded there, you could have an electron in the nucleus. All you need

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Retrieved Text: According to the Rutherford-Bohr model, electrons were thought to occupy fixed, circular orbits around the nucleus of an atom. The electrons with the lowest energy levels occupied the lowest orbits. Electrons with higher energy levels would occupy higher orbits. Whereas the planetary orbits in our solar system all lie on (or very close to) a two-dimensional orbital plane, electron orbits were believed to occupy a number of different orbital planes, spawning the concept of three-dimensional electron shells.
We know now that the Rutherford-Bohr model does not accurately represent the way in which electrons behave. They certainly do not occupy neat circular orbits - the reality is far more complex. Nevertheless, the Rutherford-Bohr model is still taught in schools and colleges because it gives us a good conceptual framework for thinking about electrons and their energy levels. For that reason, we will start by by exploring the concept of electron shells, and then go on to examine the concept of orbitals.
Before we do anything else, let's try and get a little perspective. At the time of writing, the periodic table contains one hundred and eighteen (118) elements. The first element in the table is hydrogen (H), which has the atomic number one (1) because it has one proton and one electron. The last element in the table is oganesson (Og), which has the atomic number one hundred and eighteen (118) because it has one hundred and eighteen protons and one hundred and eighteen electrons.
When dealing with the complexity of an atom's electron configuration, therefore, the worst-case scenario is

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Retrieved Text: It is necessary to know the most favourable arrangement for any given number of electron pairs surrounding any particular atom. These arrangements are found using simple geometrical constructions. This involves placing the nucleus of the atom in question at the centre of a sphere and then placing the electron pairs on the surface of the sphere so that they are as far apart as possible. The resulting arrangements are often intuitively obvious.
For the case of just two electron pairs, the arrangement is simple and the minimum energy configuration is when the electron pairs form a linear arrangement with the nucleus. In this configuration the electron pair-nucleus-electron pair angle is 180°. The coordination geometry of the central atom is described as linear.
Arrangement for 2 electron pairs on the surface of a sphere.
Three electron pairs arrange themselves trigonally, that is with bond angles of 120°. For four electron pairs, one might expect the square-planar geometry to be favourable. However, tetrahedral bond angles are 109.5°, larger than the square-planar angles of 90°. If, for the purposes of illustration, the electron pairs are assumed to be points then it should be clear that, for similar bond lengths, the electron pairs are necessarily further apart in the tetrahedral arrangement than in a square planar arrangement. There is more electron pair-electron pair repulsion in the square-planar geometry and so the tetrahedral geometry is favoured.
Arrangements for 3 and 4 electron pairs on the surface of a sphere.
The case of five coordination is a little trickier. Most molecules whose shape is determined by five

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Retrieved Text: Electron scattering from nuclei, provides us with an invaluable tool to probe the wide variety of nuclear and nucleonic properties, because it has proven itself as one of the most effective methods of studying the properties of the energy levels of atomic nuclei, so it has provided a wealth of information, mapping out nuclear ground state charge densities and precise transition charge and current densities for the excitation of single particle states and for collective states. In the electron scattering, the target is probed through the well understood electromagnetic interaction. Since the interaction is relatively weak, the measurement can be made on the target nucleus without greatly disturbing its structure. With electron scattering the cross section can be related to the transition matrix elements of the local charge and current density operators, and thus directly to the structure of the target nucleus itself. Electron scattering allows the variation of three-momentum transferred q to the target while the excitation energy is kept fixed.

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Retrieved Text: Electrons revolves around the nucleus in certain orbits. Each orbit is having certain energy level. These orbits are called stationary orbits. The orbit near to nucleus is having low energy level and the outer orbit is having higher energy level.
An electron can revolves in certain energy level without losing any energy. On addition of energy to the atom, the electron jumps to orbit of higher energy level.
‘λ’ is the wave length of light emitted (in meter).
The centripetal force due to electrostatic attraction between positively charged nucleus and negatively charges electron is equal to the centrifugal force of electron moving in circular orbits.
Where, n is an integer called quantum number.
The radius of the orbit is proportional to n2 and the velocity of electron is inversely proportional to n. These assumptions led to results which have been found correct of being tested.
It is applied to one electron atom i.e. hydrogen atom. It cannot be easily extended to explain the more complicated atoms.
It does not give any rule or restriction regarding the transition of an electron from one orbit to another orbit.
It introduced only one quantum number n. Whereas, experimental evidence concerning fine structure of spectral line suggests the more additional quantum numbers.
The quantitative explanation of chemical bonding cannot be explained by the Bohr’s atomic model.

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Retrieved Text: Electron Gain Enthalpy(EGE) is the energy released when electron is added to an isolated gaseous atom.
Atom Size – In smaller atoms, incoming electrons are placed closed to the nucleus. So addition becomes easy.
Nuclear Charge – Higher nuclear charge attracts the incoming electrons making it easy.
Type of sub-shell – The order of the electron gain enthalpy for the sub-shells is s > p > d > f. Higher the sub-shell, higher the number of electrons it can accommodate. Lower sub-shells are packed tightly whereas the higher sub-shells are packed loosely because of the high number of electrons it accommodates. Electrons added to higher sub-shells face lesser repulsion from the existing electrons in that sub-shell.
Electronic configuration – Fully-filled and Half-filled electrons in outermost shell have extra stability. Atoms which require electron to achieve fully-filled and half-filled status accommodates the incoming electrons with less energy.
Electron Gain Enthalpy is opposite of Ionisation enthalpy.
When an electron is added to an atom, energy is released.
The added electrons faces repulsion from the existing electrons but it gets support because of nuclear attraction.
When energy is required to add an electron, it is called as positive electron gain enthalpy.
When energy is released during addition of electron, it is called negative electron gain enthalpy.
Variation of electron gain enthalpy in period: When we we move across the period, the atomic radius(click this link to know why it decreases) decreases making it easy to add electrons because of higher nuclear force attraction.
Variation of electron gain enthalpy in group: When we we move down the periodic group, the atomic

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Retrieved Text: How many neutrons are present in the nucleus of one atom of ?
From the periodic table, we find that the atomic number, i.e., the number of protons in the nucleus of is 15. Given that the mass number is 32, and recalling the formula which relates mass number to the number of neutrons and protons: , we find that the number of neutrons in the nucleus of one atom of is 17.
Which atomic symbol represents a period five transition metal that has 42 electrons when it forms a cation?
Transition metals extend from groups 3 through 12 and periods 4 through 7. Ru, in its neutral state, has 44 electrons. Therefore, when it becomes a cation, it will have 42 electrons.
What is the mass number, atomic number, and charge, of the isotope of an atom that contains 34 protons, 36 neutrons, and 36 electrons?
The atomic number is equal to the number of protons in the element, so from the periodic table, we find that the element with atomic number 34 is selenium. Since , we calculate that the mass number is 70. Lastly, there are two more electrons than protons, so the charge will be .
Which of the following organizes the forces from strongest to weakest?
Covalent bonds are by far the strongest, requiring to be broken.
Next are hydrogen bonds, which require between to be broken.
Next are dipole-dipole interactions, which require to be broken.
Finally, van der Waals forces are the weakest of those listed, requiring to be broken.
Which of the following electron configurations indicates an atom in an

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Retrieved Text: In general, the size of atoms increases as a group is descended. For example, cesium is larger than lithium. As a period is transversed from left to right, the size of the atom decreases. For example, a fluorine atom is smaller than a lithium atom.
An oxygen atom gains an electron, thereby providing more electron density to shield the electrons from the positively charged nucleus. Consequently, the electron cloud expands. The anion is larger than the atom from which it was derived.
An oxygen atom with its ground state electron configuration is shown losing an electron. The cation that results from this ionization has less electron density to shield the remaining electrons from the nucleus. Therefore, the remaining electrons are more strongly attracted to the positively charged nucleus and the atom shrinks in size.

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Retrieved Text: I recently learned about orbitals in class, and I am really confused.
I am very confused about what the orbitals look like, what the signs (such as $-2s, ---2p$ etc.) mean and how they work.
What they taught us was how there are little spaces that the electrons can fit through, because they want to get to the center of the atom, and how $2s$ is in the shape of the sphere.
But I am confused how everything is laid out. Is the "sphere" shape inside the shell and around the nucleus, or is it containing the shell. but inside another shell.
They also introduced something about the $x,y,z$ axis and I am just as confused on that too.
First thing you need to understand is that orbitals are not actual physical things that exist. Simply put, an orbital is a function that describes the probability of finding the electron with certain energy at certain distance from the nucleus. The shapes of the orbitals are just the boundaries of space where you can find the electron 90% of the time.
Electrons behave both as particles and waves. Their wave behavior is described by what is called a wave function. It has two components - radial and angular. The radial component depends on the distance from the nucleus while the angular depends on the direction. It is the angular component that shapes the orbitals. Just as it is, the wave function does not have any physical meaning, but it's square is proportional to the probability of finding the electron in a particular region

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Retrieved Text: Could this be a plausible way to find out how an electron moves around the nucleus in a hydrogen atom?
Are there fields corresponding to the composite particles (e.g. hydrogen atom field)?
How can we prove that 1 electron was in 2 places at one time. Theoretically, how could we ever prove this? How would we distinguish between one electron being destoryed and 2 "partial" electrons being created with different properties than the first?
We know that particles only exhibit wave-like characteristics only when in motion, and also that the electron can be accurately described as a Standing wave, therefore the electron must be in motion around the nucleus.
Since at any one time the electron has a 95% probability to be anywhere in a certain orbital, the electron must be moving at a very high velocity $v$.
A hydrogen atom is suspended at at distance of more than 1 meter from a heavy nucleus which has a sufficient atomic mass such that under its influence pair production can occur.
very implausible, since it is based on assumptions that are gross simplifications of the real situation. You cannot simply postulate whatever you like!

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Retrieved Text: As an electron approaches a nucleus from infinity, it becomes 'bound' - it is attached to the nucleus, if you like. In this bound state, the electron occupies what is called an energy level. A nucleus has a discrete number of energy levels, and so electrons bound to a certain nucleus can only take on certain potential energies. These energies are negative by convention.
The lowest (most negative) energy level is denoted n=1, the next lowest n=2, and so on. The values of these can be found using formulae which you don't need to know about. Alternatively, they may be determined experimentally.
Energy levels in a hydrogen atom. The transition shown from the n=3 level to the n=2 level gives rise to visible light of wavelength 656 nm (red).
where E is energy, h is Planck's constant (6.63 x 10−34 J s), f is frequency, c is the speed of light, and λ is wavelength.
The energy levels of different nuclei are different. Evidence for these energy levels comes from the emission and absorption spectra of atoms. An emission spectrum can be obtained by heating a sample of an element. This gives the electrons energy, so they jump up the energy levels. At random, they then jump down again, giving off photons with measurable frequencies. The formulae above can be used to calculate the difference in energy between the levels between which the electrons have jumped.
An absorption spectrum can be found by passing light through (for example) a gas, and observing the frequencies of light which are absorbed. These frequencies

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Retrieved Text: How many times have you used an electronic device and the batteries died? Wouldn’t it be great if batteries could last for 10 or 15 years of normal use? Betavoltaics might be an answer to solving this problem of limited battery life. Get ready to get charged up about this “potential” game-changing technology.
Voltage is the energy carried by a charge. It can be measured as the difference in charge between two points of a circuit. Current, on the other hand, is a measurement of how much electricity passes a certain point on the circuit.
What is the difference between electrical power and electrical energy?
Electrical power is the rate of energy being provided at a specific instance, whereas electrical energy is the amount of power provided over time. Therefore two identical light bulbs would have the capacity to use energy at the same rate and therefore have the same "power" but one may only be on for ten seconds and another for ten hours, so the amount of "energy" used is different.
How do batteries provide electrical energy?
Batteries produce electricity from a chemical reaction. Inside the battery are a cathode and anode. The cathode is connected to the positive terminal, and the anode is connected to the negative terminal. A separator inside the battery keeps the cathode and anode from touching. When the battery is connected to a circuit, a chemical reaction takes place in both the cathode and the anode. The reaction in the anode releases electrons, and the reaction in the cathode accepts these electrons. To get

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Retrieved Text: Classically, I think it is correct to say that Maxwell implies an accelerated electron will "radiate"
What is the quantum take on this please? In particular, what determines the wavelength of the emitted photon?
PS I may ahve asked something like this before, but I never found an answer. This is a re-phrasing of the question.
PPS I know one should not try to interpret what the maths says in practical terms! cf, maths of a car's front suspension is same as how you tune a radio, but my radio is not made of springs and shock absorbers!
It is the same quantum mechanically. That is why the electron in an atom cannot be said to orbit the nucleus, as otherwise it would be accelerating and thus emit radiation and lose energy. Instead, quantum mechanics showed that the electron is in a stationary state around the nucleus.
"Accelerated electron photon emission" You must log in or register to reply here.
Electron energy states and photon emission?

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Retrieved Text: Periodic table[ edit ] Electron configuration table The form of the periodic table is closely related to the electron configuration of the atoms of the elements. Phosphorus, for instance, is in the third period.
Pauli-Exclusion Principle Wolfgang Pauli postulated that each electron can be described with a unique set of four quantum numbers. The electron configuration can be visualized as the core electronsequivalent to the noble gas of the preceding periodand the valence electrons: It is possible to predict most of the exceptions by Hartree—Fock calculations,  which are an approximate method for taking account of the effect of the other electrons on orbital energies.
Nitrogen, for example, has 3 electrons occupying the 2p orbital.
In bulk materials, this idea helps explain the peculiar properties of lasers and semiconductors. That is, we follow the three important rules: For atoms, the notation consists of a sequence of atomic subshell labels e.
It may be stated as: However, the energy of an electron "in" an atomic orbital depends on the energies of all the other electrons of the atom or ion, or molecule, etc. Hund's Rule Hund's Rule states that when electrons occupy degenerate orbitals i.
The electronic configuration for Cl- can, therefore, be designated as 1s22s22p63s23p6. The fact that the Aufbau principle is based on an approximation can be seen from the fact that there Atom and electron configuration an almost-fixed filling order at all, that, within a given shell, the s-orbital is always filled before the p-orbitals.
If that were the case, the 3d-orbital would have the same energy as the 3p-orbital,

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Retrieved Text: While I don't think disambiguation is needed between physics and music, it idly occurred to me to think of the equivalent of energy levels in heavily electronically assisted music groups. Clearly, a lead vocalist is closer to the nucleus than a backup singer. If Lady Gaga were an electron, she presumably would not shift to a backup band.
Actually, if I think back to when I studied the aufbau of a periodic table consisting of earth, water, fire and air, I remember the term being "electron" levels rather than "electronic". If current expert practice is "electronic", by all means keep it. "Electron", however, might be less ambiguous.
This page was last modified 18:32, 4 January 2011.

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Retrieved Text: antiparticle: Particle having the same mass, spin, isospin as a particle, but having all additive quantum numbers opposite to those of its respective particle. Antiparticles have the opposite charge of its corresponding particle. Antibaryons are antiparticles to baryons, antileptons are antiparticles to leptons, and antiquarks are antiparticles to quarks. The antiparticle for a particular particle, for example a neutrino, is denoted an antineutrino.
atomic mass unit (amu or u): Unit of mass defined by the convention that the atom 12C has a mass of exactly 12 u; the mass of 1 u is 1.67 ¥ 10-27 kg.
becquerel (Bq): Unit of activity in the International System�one disintegration per second; 1 Bq = 27 pCi.
beta particle (beta radiation, beta ray): An electron of either positive charge (e+ or b+) or negative charge (e, e-or b -) emitted by an atomic nucleus or neutron in the process of a transformation. Beta particles are more penetrating than alpha particles but less than gamma rays or x-rays. Electron capture is a form of beta decay.
boson: A particle having spin that is an integer multiple of h .
conservation law: A relation asserting that a specific quantity is conserved. For example, conservation of energy, conservation of momentum, conservation of electron number. Conservation laws are connected to symmetries through Noether's theorem.
curie (Ci): The original unit used to describe the intensity of radioactivity in a sample of material. One curie equals thirty-seven billion disintegrations per second, or approximately the radioactivity of one gram of radium. This unit is no longer recognized as part of the International

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Retrieved Text: Q17: October 20, 2003: I do not understand why in your mind there is something more fundamental with the electron and consider it a particle that exists, but a photon does not. You can perform the double slit experiment with an electron or photon and obtain the same wave / particle issue depending on the experiment.
A17: You are able to "catch" an electron, hold it still and observe it. You can not do the same with a photon. It is this characteristic of being able to observe an entity at rest that makes it substantive. It seems to appear as well that, when an entity can be observed in this way, it also has mass and occupies a regionally distinct volume. Now when we discuss a wave, we never hold this level of observation to be true. We understand that a wave is the sum of a multitude of positions, velocities, forces, vectors, etc. and to "catch" a wave, hold it still and observe it, is meaningless.
When the double slit experiment is conducted with light, it is fairly straight forward to understand the effects, if light is considered to be a wave being detected by electrons. When a single "photon" is "emitted", we may consider that a single electron in the source moved from the excited state to its rest state. This means that one and only one electron at the target capable of absorbing the discrete amount of energy will transition to the excited state. To excite more, would violate the Law of Conservation of

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Retrieved Text: It might be some way off but computers users in the future could take data off a disk drive and move it into the nucleus of an atom.
Scientists have demonstrated what is being called the "ultimate miniaturisation of computer memory," storing data for nearly 2 seconds in the nucleus of an atom. This is a key step in the development of quantum computers, according to the National Science Foundation (NSF).
Using a new technique, an international team of scientists "demonstrated that information stored in the nucleus has a lifetime of about 1 ¾ seconds," said the NSF, describing a new study in the journal Nature. "This is significant because before this technique was developed, the longest researchers could preserve quantum information in silicon was less than one-tenth of a second. Other researchers studying quantum computing recently calculated that if a quantum system could store information for at least 1 second, error correction techniques could then protect that data for an indefinite period of time."
The scientists, from Princeton University, Oxford University and the US Department of Energy, broke the 1-second barrier with a system that uses the electron and nucleus of a phosphorous atom embedded in a silicon crystal. The electron and nucleus each behaved like tiny "quantum magnets" that could store quantum information, but the instability of the electron made it unsuitable for storing information. "To overcome the problem, researchers moved the information into the nucleus where it survived much longer," the NSF states. Data in the electron cloud, which is a million times bigger than the

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Retrieved Text: Bohr's idea that electrons are found in different orbitals or energy levels was an important step in understanding the structure of an atom. Louis de Broglie's particle-wave relationship was also a crucial development.
Werner Heisenberg and Erwin Schrodinger were able to take these ideas and develop modern quantum mechanics. The main significance of quantum mechanics is the ability to very accurately predict physical properties using basic mathematical principles. Heisenberg and Schrodinger used different kinds of mathematics to explain atomic structure, but they ultimately reached similar results.
The key approach by Schrodinger was to recognize the factors influencing the energy of an electron in an atom. He saw that there would be contributions from Coulomb's law, because of attractive forces between the electron and the nucleus as well as repulsive factors between different electrons. In addition, Schrodinger recognized that there would be a kinetic energy component related to the wavelength of the electron. Schrodinger combined these factors into "the Schrodinger wave equation."
Figure AT3.1. The factors Schrodinger accounted for in his wave equation. Each factor influences the energy of an electron.
Solving the wave equation is very useful. A solution to the equation, which is called a wave function, can indicate the energy of an electron in an atom. The solution can also be combined with other mathematical relations that will give specific predictions of different properties of atoms and molecules.
The Schrodinger wave equation is an approach to describing an electron.
The solution to the wave equation is called a wavefunction.
What happens to the energy of an electron as its wavelength gets

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Retrieved Text: For further discussion, see also Theoretical chemistry and Quantum chemistry.
In chemistry, a chemical bond is an arrangement of electrons among atoms that keeps the atoms together. The bond originates in the electrical attraction of opposite charges, and is made possible by the attraction of the positive nucleii of atoms to the electrons associated with them. The central issue in understanding the bond is finding how the electrons associated with atoms distribute their negative charge so as to overcome the natural repulsion between positive atomic cores. A useful understanding can range from an entirely qualitative model based upon the attraction of one atom for electrons compared to another (their electronegativity) to very detailed computer calculations based upon quantum mechanics.
If the total energy of two or more bound atoms is lower than the sum of the energies of the free component atoms, the aggregate of atoms form a stable molecule (or crystal) and the energy lowering is the binding energy of the molecule (or crystal).
The chemical bond takes on many forms, ranging from simple atomic pairs in a diatomic molecule, to large organic molecules like DNA. Examples of atomic pairs are two nitrogen atoms chemically bound to the stable dinitrogen molecule (written as N2) and a hydrogen atom with a fluorine atom forming hydrogen fluoride (HF). As an example of larger complexes, carbon (C) and oxygen (O) form the pair C—O that appears in many organic molecules, one of the simplest being methanol H3C—OH. Atoms may also be bound to form a crystal, such as sodium (Na) and

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Retrieved Text: An atom is the smallest particle of matter that can combine chemically with another atom or molecule. It has a nucleus, composed of protons and neutrons, around which electrons orbit.
The electron carries a charge equal to the proton but opposite in charge (-e).
An atom has as many protons as electrons. The total charge is zero which is why matter is usually neutral.
In some cases, with the help of an external energy input, an atom can lose or gain one or more electrons. This is the phenomenon of ionization.
Example: An atom of sodium (Na) has 11 protons and 11 electrons. If it loses an electron, it then has 11 protons but only 10 electrons. A positive charge +e is no longer balanced and the resulting sodium ion is positively charged. The sodium ion, Na+, indicates that it carries a charge +e.
A molecule is an assembly of atoms that share electrons to achieve greater stability.
Click on one of the four active zones to start the animation.
To know the structure of an atom and a molecule.
To define an electrical charge.
To understand the phenomenon of the ionization of an atom.
To know the difference between a valence electron and a free electron.
To recognize two types of atomic bonds.

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Input Text: Read the passage below and choose the right answer to the following question (choices are red wagon or blue wagon ):

The full box is harder to move because it has greater mass and therefore greater inertia.


Sally is pulling two wagons. The red wagon is full of sand, and the blue wagon is empty. The wagon that will be more difficult to pull is the red wagon or blue wagon?

Target Text: red wagon

#### Retrieved Documents ####

Rank: 0
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Retrieved Text: Having a wagon as a child is one of my fondest childhood memories. Buying your child a wagon will not only put a smile on their face but yours as well. You will make countless memories with your children as they grow up and if you own a wagon it will be part of those memories. There are so many great uses for a wagon. They are a great alternative to using a stroller and are loads of fun. They can be used for long walks around your neighborhood and parks. Some wagons can not only be used for recreational purposes but practical purposes too like hauling backyard materials. They even have wagons made just for the beach. Once you own a wagon, you will use it all the time. Since there are so many different types of wagons, we composed this list of the top 6 wagons for kids. We made our choices by doing product research, reading countless reviews online, looking at star ratings on Amazon.and personal experiences. All of the wagons listed below have a 4-star rating and up.
This classic style wagon is designed to have a smooth ride on all different types of terrain. It has a steel body with natural wood sizes. The high wooden stake sides let your child sit comfortably and safely inside while keeping their hands and fingers secure. It’s 10″ rugged rubber tires can easily be filled with air to keep that nice and smooth ride. Extra long handle for easy pulling. The handle also folds under

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Retrieved Text: Do you have happy childhood memories of pulling around, or being pulled around in a wagon? Do you want your little ones to have the same experiences to treasure for life? With so many to choose from which are the best kids wagons?
My little ones love their red wagon. They pull their toys around in it when we’re at home and enjoy riding in when we’re out.
I have to admit I love it as well. It’s so much easier to have the kids, all their stuff, and anything I need in one place. Much easier than a stroller with kids inside, or walking alongside, and bags hanging from the handles.
Let’s look at why you should get a wagon, what to look for, and our top 10 picks.
We ♥︎ honesty! Mom Loves Best earns a commission through the hand picked links on this page at no extra cost to you.
Use the links above to check the latest prices or read our in-depth kids wagon reviews below.
Why Do I Need a Push Wagon?
How Do I Choose a Push Wagon?
These versatile workhorses offer a great alternative to a stroller and give you the chance to carry things easily. You can get the kids, the picnic, some of their toys and more in some wagons.
Kids also love wagons, whether it’s pulling friends around or sitting inside with a friend or sibling. Even the little ones can have their own wagons.
You can take a wagon along when you head to the beach, the park, on the trail, around the neighborhood for

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Retrieved Text: The red pull-along, ride-in wagon has become synonymous with the joys of childhood.
This isn’t surprising as children like to be pulled along by their family members and friends while riding on these wagons, as well as pulling along their precious possessions. The wagon is such a staple of childhood that parents and grandparents today have fond memories of it.
Of course, the physical and mental benefits that come from playing with these wagons cannot be dismissed either. Child psychologists agree that the proper and regular use of wagons among children strengthens their muscular, social and cognitive skills, especially during cooperative play.
Parents agree that just seeing their children enjoy their wagons is sufficient reward for the time and money spent on buying these toys.
Here are our top 12 picks for the best kids’ wagons. Choose based on your budget, as well as your kid’s age, weight and preferences to get the best bang for your buck.
The Step2 brand is known for the versatility of its products in the sense that they “grow” with your kids and/or have multiple uses. This is true for this All Around wagon, which has two main uses: first, as a pull-along wagon with and without a canopy; and second, as a flatbed or table for your little ones to enjoy.
As a pull-along wagon, it has comfortable seats for your kids to sit on while being pulled along. They can be installed or removed depending on their preference.
As a flatbed or table, the seats can be flipped over to transform into a larger flat

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Retrieved Text: Since 1917, kids everywhere have loved riding their Radio Flyer trikes and wagons.
Radio Flyer Wagon Umbrella Toy Kids Play Children order black friday online Radio Flyer Wagon Umbrella Toy Kids Play Children Compare prices for for best toy websites.
Radio Flyer also produces scooters, tricycles, bicycles, horses, and ride-ons.
Like all Radio Flyer wagons, this one has heavy axles to handle a lot of weight,.Radio Flyer is the official maker of the little red wagon, tricycles and other safe.Save up to 15% with these current Radio Flyer coupons for October 2017.
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Now save with free Radio Flyer coupon codes and discount promo codes to Radio Flyer at ETcoupons.com.Radio Flyer Coupon Code Free Shipping was written by admin yesterday, more image and video.Radio Flyer is an American toy company best known for their popular red toy wagon.
Well, in this article I will show you two nostalgic wagons that your child will love.RadioFlyer.com is the official source for the latest Radio Flyer promo codes, coupons and special offers. Now Until July 4th,

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Retrieved Text: Summary: The FLA wagons are low-floor container carriers, capable of accomodating the increasingly popular �high-cube� ISO containers within the British loading gauge. Formed into 2-, 3-, 4- or 5-wagon sets, they can be seen mixed in with other wagon types on Freightliner services across the country.
History: The global adoption of ISO standard containers revolutionised international freight transport, allowing cargoes to be handled and transported more easily and quickly. However, although the standard rigidly specifies the container width and length, the height is less constrained. Early ISO containers were 8ft or 8ft 6in tall, these later being joined by 9ft and 9ft 6in tall �high-cube� containers. The Freightliner wagons built in bulk by BR in the 1960s and 1970s were able to carry 8ft tall containers and, following gauge clearance enhancements, 8ft 6in boxes on most routes. But for the taller boxes, which were becoming increasingly popular with shipping companies, new designs of wagon were required.
The FLA was the first successful type capable of carrying �high-cube� containers but it is worth mentioning some of the other designs that preceded it.
In the early 1980s, The Standard Railway Wagon Company was proposing a 2-axle well wagon rather like a stretched Lowmac (an artist�s impression was published in the book �British Railfreight Today and Tomorrow� by Geoffrey Freeman Allen, published by Jane�s in 1984). This would be able to carry 20ft long, 9ft tall boxes in the central well, or 30ft long, 8ft 6in tall boxes across the two end platforms. The wheelbase of almost 9 metres would have been

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Retrieved Text: . . . and babies make four.: Happy Memorial Day!
We live in a town that happens to love parades. There is one for St. Patrick's Day, one for the Fourth of July, one for pets and, the granddaddy of them all, one for Memorial Day.
This year the girls got to be in the parade instead of just sitting on the curb watching the parade go by. We decorated their wagon, bought candy to give out to the kids along the parade route and met at the parade start along with high school bands, military bands, fire engines, politicians and scout troops. We were marching with the twins club I belong to so we were joined by other "doubles" also in strollers or wagons.
When it was finally our turn the girls asked about 10 times if we were "IN" the parade and then started waving like seasoned parade pros.
Then they wanted out of the wagon to hand out candy.
And I let them out.
You'd think I was new at this.
It's not easy -- actually it's nearly impossible -- to manage two children trying to slowly hand out candy, while flatly refusing one one bit of help, while also pulling a red-white-and-blue-emblazoned wagon. It is especially difficult when the 75-piece band behind you is literally about to run you over. And once out of the wagon Kenna never wanted in again. So, I got Michal back in and carried Kenna for the entire rest of the parade.
We'd arranged for Eric to meet us mid-route and I was so happy

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Rank: 8
Score: 62.10857
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Score: 61.647057
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Retrieved Text: Improper wiring can activate the wagon’s motor unintentionally, posing an injury hazard.
Radio Flyer at 800-621-7613 from 8 a.m. to 5 p.m. CT Monday through Friday or online at www.radioflyer.com and click “Product Recalls” for more information.
This recall involves Radio Flyer’s eWagon children’s battery-operated electric wagons. When force is applied to the wagon’s electric handle, the motor activates to power the wagon. The foldable wagon is constructed of red and gray fabric and a steel frame and measures about 41 inches long, 25 inches wide, and 42 inches tall. The wagon has a removable canopy, two seats with seatbelts, four cup holders, a storage pouch, a removable battery and a telescoping handle where the power button is. The Radio Flyer logo is printed on each side of the wagon. Only wagons with model number 3912/3912A are included in this recall. The model number can be found on the handle warning label located near the pivoting joint.
Consumers should immediately stop using the recalled wagons and contact Radio Flyer for a full refund.
The firm has received two reports of the wagon’s motor activating unintentionally. No injuries have been reported.
Toys “R” Us stores nationwide and online at www.radioflyer.com and www.toysrus.com from August 2017 through January 2018 for about $350.
Radio Flyer Inc., of Chicago, Ill.

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Retrieved Text: BR Olive 12T Pipe Wagon.
BR Baux 12T Pipe Wagon.
GWR Shunters Truck BR Black 'Margam Jn' Weathered.
BR VDA Box Van weathered.
BR YGH ‘Seacow’ Bogie Hopper BR Departmental Olive Green weathered.
12 Ton Southern 2+2 Planked Ventilated Van LMS Grey.
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Conflat Wagon BR Bauxite (Early) With ‘Speedfreight’ Ventilated BA Container.
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7 Plank End Door Wagon 'Park Lane Wigan'.

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Retrieved Text: The Tigo S is a compact loader wagon series with a controlled feed unit, Lely provides the correct model for any operation with 3 (classic models) or 5 swing arms. The high performance chopping unit can be fitted with up to 33 knives, which are easy to replace. The low loader models with low centres of gravity and wide tracks appeal to users due to their safe operation on slopes and their low empty weight.
The new Tigo S Profi series has been developed especially for the modern, high performance agricultural business. The camless pendulum pick-up with five rows of tines ensures clean pick-up of crops. The feed unit is powered by a heavy duty gear drive and has five stable feed forks to transfer the crop smoothly and extremely gently into the wagon. The Tigo S Profi series is available in four wagon types from 40 to 70 m³ and two discharge wagon models.
The Tigo R models are loader wagons for medium to large agricultural businesses, which produce their own silage. They are robust and provide increased capacity. These wagons are fitted with a 31 knife 800 mm chopping rotor and a 5 tine bar non-steered pick-up. The configuration of these wagons is simple but it boasts high capacity and ease of operation.
The Tigo R Profi models are used by agricultural contracting companies. The unique non-steered pick-up features 7 tine bars; the high performance rotor is 800 mm in diameter and has 7 spiral-shaped tines on each bar. 40 chopping knives cut crops to 37 mm.

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Rank: 14
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Retrieved Text: In 1976 Queensland Railways placed an order with Commonwealth Engineering at Salisbury, Brisbane, for 125 HWO class drop-sided open wagons. They were to be the last open wagon type purchased by QR, and the largest drop-sided open wagon to be operated on the Queensland system.
Running numbers for the 125 members of the HWO class were from 39480 to 39604. All were delivered between August 1977 and March 1978. When ordered in 1976, they cost $30,139.00 each.
The drop-sided door design allowed for easy loading of many styles of general goods not requiring a box wagon. When loaded with palletised goods, they were often tarped prior to dispatch, and lashing rings were provided for tarping along the side of the wagon below the doors. The floor of the wagon was a composite design of steel and hard wood timber, with the timber slightly raised to ensure the cargo was resting on wood when loaded. The raised ends of the wagon also featured timber on the inside face.
When delivered, the HWO wagon featured steel doors with pressed vertical ribs for strength. From the late 1980's, the HWO fleet went through a rebuild and refurbishment program which included replacing the original doors with a new pattern that was much stronger. The new pattern door featured a flat plate steel inside face, with steel box section framework on the outside. During this rebuild program, a data plate was also fitted below the wagon body line to carry the individual wagon number and information. From the early 1990's, buffers were progressivly removed

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Rank: 15
Score: 60.4799
Retrieved Text: Vintage Dan Patch Horse Steel Coaster Wagon RARE!!!
Look here to find old Radio Flyer wagons, vintage red wooden wagons, tin wagons, antique Playskool wood toy wagons and many more appearing on sale daily!
Vintage Playskool Wooden Dairy Wagon Pull Toy 6 Milk Bottles With Chocolate!!!
RARE VINTAGE HOLGATE WOODEN WAGON PULL TOY - FREE SHIPPING!
Vintage Speedway Series Little Red Wagon - New In Box - Free Shipping!

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Rank: 16
Score: 60.047047
Retrieved Text: Roll out the red wagon…this little fox is going to market! We made tissue box wagons, grabbed our shopping lists, and headed to the market to play a vegetable matching game. Sporting fox ears and tails, naturally.
We read Red Wagon by Renata Liwska (Philomel Books, 2011). Lucy the fox has a new red wagon and a big job to do. She must take her mother’s list to market and buy some groceries. Lucy sets off with her animal friends, and while they do eventually bring the veggies home, they also have adventures as the red wagon transforms into a boat, covered wagon, caravan, train, rocket ship, and construction vehicle. After Lucy’s big day, the red wagon serves one final purpose…a place to take a nap!
We’ll begin with the little red wagon! Cut a large tissue box down to 1.75″ inches tall, then wrap with red paper. You can go with our standard wheel assembly (instructions here), or hot glue shortened paper towel tubes the bottom of the box to suggest wheels, and drag the wagon on the fixed tubes.
For the wagon’s handle, you can use a simple pull string, or you can make a drinking straw handle like we did. To make our handle, thread an 16.5″ piece of string through a drinking straw. Pull 1″ of string out of the straw, fold it down, and tape it to the side of the straw. The other end of the string should extend, unattached, from the opposite end of the straw.
Next, cut two notches the center of

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Rank: 17
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Retrieved Text: The famous Radio Flyer 2700Z Pathfinder Wagon offers classic durability, fun, and safety that will definitely please both kids and adults. This high-quality wagon has cup holders and flip-top seats that your child can use to lean back on. The seats can also be laid back to store personal items in the wagon as well. It comes with safety belts, wide storage space, and a long handle for hauling. It’s designed for kids ages 1 to 2 years and above. The Radio Flyer Pathfinder Wagon also includes axles in the front designed for extra safety.
Amazon.com (check current discounted price with free shipping) seems to have the best price for it. We also love their customer service as well.
This wagon is made of durable plastic with the classic red color of Radio Flyer. Setting up the wagon can easily be done with the illustrated instructions they provide. Amazon has also made this package Frustration-Free so it’s very easy to open and start using the wagon pretty quickly.
This wagon is made of durable plastic, easy to haul, and has a front axle with security features.
The tires are Dure-Tred, designed for an easy, comfortable, and safe ride.
Seats can be folded up or down.
Includes cup holders, alternative storage space, and two seats with seatbelts.
Branded by Amazon as Frustration Free Packaging.
On average, customers rated Radio Flyer Pathfinder Wagon 4.5 out of 5 stars on Amazon. Customers really like the hard and sturdy plastic build of this wagon so that the wagon will last a long time through all the bumps and

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Rank: 18
Score: 59.873154
Retrieved Text: Articles About Our Products and How They Work.
The Problem With Red Wagons.
What’s the problem with the standard "little red wagon”? Well, it depends on what you plan to use it to do. This old reliable product in either plastic or metal has withstood the test of time—it certainly works and transports cargo well. The problem is that the standard red wagon won't fit in most small car trunks as the wheels do not fold like a Pancake Flat wagon's foldup, patented wheels. (Try stacking two red wagons, for example.) The Pancake Wheel technology, with its compact, folding wagon and cart products provide the cargo benefits of a traditional wagon or cart, with the added benefit of easy compact, foldup storage. Only after Pancake Wheel invented the Pancake (R) folding wheel and related handle technology did many wagon and cart manufacturers take notice of consumer's desires for fold flat wagons and carts, but no other solid base wagons or carts compare to the world thinnest Pancake flat wagons and carts in terms of how flat they fold up. We have begun licensing our fold flat technology to savvy manufacturers so look for our products for sale! During 2011, Pancake Wheel licensed our folding handle designs to Radio Flyer as Radio Flyer recognized that consumers desire to fold wagon handles out of the way. Our fold flat handle provides holding positions for the folding handle so it won't drag on the ground, and even better, the handles folds flat right inside the wagon when not used.
Jogger Truly Folds

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Rank: 19
Score: 59.266243
Retrieved Text: The Owners of Werner Wagon Works, Connie and Don Werner, stand in their Horton shop. The couple are thrilled to have one of Don’s wagons chosen to be in President-elect Barack Obama’s Inauguration Day parade on Jan. 20.
Horton ? For years, Don and Connie Werner have led the Lawrence Old-Fashioned Christmas Parade down Massachusetts Street in their covered wagon.
On Jan. 20, one of Don’s handcrafted wagons will parade down a much bigger street: Pennsylvania Avenue.
“We are just elated, just plum tickled about that,” said Don, who owns Horton-based Werner Wagon Works along with his wife.
This fall, Don was building a custom chrome hitch wagon for the McCrossan Boys Ranch in Sioux Falls, S.D. He was about three-quarters of the way done when he received a call from the ranch’s admissions director, Troy Geis, who asked how the project was going.
“He said, ‘I think we need to step it up a little bit, we might be picked to go to the inaugural parade,'” Don said.
The deadline was to have the wagon finished by the beginning of November so photos could be taken of the metallic green wagon.
“I said, ‘We will be cutting her thin, but I think we can make it,'” Don recalled.
Two weeks after the wagon left the Werners’ shop, they learned it would be in the Inauguration Day parade.
“I mean it’s just a privilege. This is historical-type stuff,” he said.
The McCrossan Boys Ranch, which works with at-risk youths in South Dakota, was one of about 1,400 organizations to submit entries for the parade. Only about

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Rank: 20
Score: 58.93867
Retrieved Text: Legacy of legendary St. Louis wagon builders endures.
Variations in condition, originality and completeness can affect resale values of vintage wagons. This Linstroth wagon not only benefits from vibrant original paint and sound wheels, but also retains its original seat and folding end gate.
This early color image shows an artist's rendering of the Luedinghaus "tower of wagons" displayed at the 1904 World's Fair in St. Louis.
Color advertising was expensive: It was used sparingly by wagon makers. This Luedinghaus image was part of a promotional flyer outlining the brand’s advantages.
Colorful and attractive promotional items such as this Gestring wagon watch fob garnered plenty of attention while helping reinforce the desirability of the brand.
This Weber & Damme wagon is being unloaded at a local train station. Period photography helps us better understand how early vehicles were used while often eliminating misconceptions and stereotypes.
Located at the Santa Ynez Valley (Calif.) Historical Museum, this Gestring wagon features a 43-inch box width, St. Louis seat risers and contoured woodwork on the spring seat. The third set of sideboards (top box) are original. Designed to slope downward from a near 7-inch height in the front to just over 2 inches at the back of the wagon, they are extremely rare.
Many of St. Louis' early wagon makers were positioned near steamboat landings. Such areas were a hub of activity, where supplies were unloaded and others were shipped west.
These rare, original letters from Joseph Murphy date to 1883 and 1887. Each has helped solidify his reputation for expert woodwork and high-quality vehicles.
Wagon makers often used

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Rank: 21
Score: 58.43678
Retrieved Text: One of the ways that the N Gauge Society has been celebrating its 50th anniversary has been to team up with Peco to produce a selection of exclusive wagons from their well-established range.
The 50th anniversary marks a significant milestone for the Society and for N Gauge itself. Few can deny that without the product support from Peco over most of that time, N Gauge (and the Society) would not be where it is today. Peco’s founder Sydney Pritchard was member number 2 of the Society, a membership number that is still held by Peco to this day.
The Society has made a varied selection of interesting wagons to hopefully cater for most members. While they are all equally appealing, pride of place perhaps goes to the 7 plank coal wagon for G Simmons, as the eagle-eyed will note that it is number 50. The prototype was a GER registered 1909 built 7 plank wagon without end-doors, exactly as per the Peco wagon.
The all-steel Austin Motor Company wagon is well-suited to the Peco model, having side and end doors. Built in 1928 it is possible that they were only used internally, although they were registered by the LMS, and probably carried coal from North Staffordshire collieries to the Longbridge factory.
The Peco ‘salt’ wagon is very distinctive, and for a change, the livery of Tollemache is for the carriage of pulverised coal. This wagon has been produced in other scales but never in N Gauge. The prototype wagon was built in 1920 and converted for pulverised coal in 1926

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Rank: 22
Score: 58.418747
Retrieved Text: Do you love to take walks with your little kids until they complain they’re tired after you’ve only gone one block?
How about walking with more than one small child? It can be frustrating for parents who want to take walks, attend outdoor art fairs, camping or countless other activities. A kid’s wagon can make all of that so much easier, plus your kids will love to play in the kids’ wagon.
Choosing the best wagon for kids is a big decision. You need to consider safety factors as well as quality and how well the wagon works. Here we have examined 10 of the best wagons for kids and the best wagons for toddlers in 2017.
Little Tikes presents this study kids wagon with QuietRide wheel technology for a less noisy ride. It comes with a removable umbrella to provide a shady ride, a cooler to transport cold drinks and snacks, and drink holders.
The sides are removable so you can convert it into a bench that even an adult can sit on. The wagon handle can be folded underneath for easy storage when not in use. Seatbelts keep your children safe when they’re being pulled along. When the kids are not playing with it, you can even use it to pull along supplies for your yard or gardening projects.
This deluxe wagon really has it all for a relaxing ride and converts to a great place to sit and relax. With the cooler, it makes snack time a breeze. It’s made in the USA and customers absolutely love it.

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Rank: 23
Score: 58.134056
Retrieved Text: Little Adam sat up and looked around. He saw his stepmother and she didn’t look good. Adam became scared and went over to her and got a rag and wiped her face. “Mom! Mom! Are you okay, Mom! Pa!” he screamed, “go get her some help, she is hurting so badly!” Inger was in the middle of a contraction and was unable to respond to the child; the contractions were about a minute apart.
When she could get a deep breath, she looked at Ben and yelled, “Go Now! Go get Sally; she has had the most experience since she has six children of her own. She will know what to do!” Ben quickly turned and jumped out of the wagon and went over to the Carver wagon. He knocked, loudly.
Sally was praying that this child would not tear Inger badly but she was sure that he would be big and she could only do so much. Inger began her pushing, it took about six good pushes and her son entered the world screaming. He was big! “Oh, Inger,” squealed Sally, “he is beautiful! Big, pink and beautiful!” She placed the newborn on Inger’s’ stomach and prepared to cut the umbilical cord. As she turned around, she saw that Ben had placed the boiling water on a ledge with the knife inside and she quickly grabbed it and cut the cord. At that time, she tied the cord and began to wait for the next set of contractions to deliver the placenta. With this complete, Sally wrapped

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Rank: 24
Score: 57.862972
Retrieved Text: LARGE CAPACITY: Large load folding wagon cart outside dimensions approx: 39.37"Lx21.65" Wx25.98"H. The collapsible utility wagon cart inside size is 31"Lx17.7" Wx10.6"H. Ground to the top of the handle:38.6". Two cups are not included.
WEIGHT CAPACITY: The wheel of the canvas wagon is 4" wide and 7" in diameter, the utility wagon collapsible heavy duty frame allows loads up to 300lbs. The spacing of the wheels can be adjusted randomly to suit different road surfaces. The folding wagons cart fabric material 600D Polyester, and it is removable for easy hand or hose washing, camping beach wagon cart frame material steel, the beach outdoor utility wagon cart sturdy black steel frame is more stable.
360 DEGREES BEACH WHEELS AND ADJUSTABLE HANDLE: The folding wagon come with heavy duty 7"x 4" thick rubber wheels - rotates 360, the spacing of the wagon cartwheels can be adjusted randomly to suit different road surfaces. Telescoping handle provides an easy control on most terrains, camping wagon cart handle can be adjusted height and adapted to the different height person push the cart.
EASY TRANSPORT: Sets up in Seconds, No Assembly Required! Folding into the carry bag for convenient storage. Small enough to fit in the closet, on the wall or in the trunk of any standard car. Folding utility wagon cart is perfect for transporting shopping, on family outings or as a goods trolley, and great for trips to the beach sand, garden, park, camping, outdoor sporting events, or just move things.
SATISFACTION GUARANTEE: Refund or replacement within One Year are guaranteed! Provide you a

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Rank: 25
Score: 57.74872
Retrieved Text: 1) All demands for despatch of goods in wagon loads will be entered in the Wagon Demand/Priority Register maintained at the stations or goods sheds open for booking of goods in wagons loads. The signature of the sender or his representative will be taken in the appropriate column provided in the register after duly filling in all the other columns. The prescribed registration fee will have to be paid by the sender or his representative at the time of registration of demands for wagons.
2) A forwarding Note duly filled in should be tendered by the sender at the time the goods are physically brought into the Railway premises.
3) (a) A limit may be placed by Railways on the quantity of goods permitted to be registered at a time by one indentor.
(b) When booking is restricted to a particular station or by a particular route, full details regarding the restrictions will be exhibited at the station.
(c) When limits are placed on the Registration of goods in the manner indicated above, full details thereof will be exhibited at the Stations.
4) When Booking is restricted to a particular Station or a particular Route, full details regarding restrictions will be exhibited at the Station.
a)Traffic in any commodity offered by Platinum & Gold card holder from their siding.(If they cancel their indents under any of the circumstances notified in Rule 201(15) of Goods Tariff M.41, Part I, Vol.I an amount equal to wagon registration fee may be collected).
b)Container Traffic Booked by CONCOR.
c)Railway Materials and Stores booked by Railway officials in their

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Rank: 26
Score: 57.558697
Retrieved Text: What better way to enjoy the changing season then by visiting the Barn for a wagon ride to the “Back Forty”. Our wagons takes you on an enjoyable tractor pulled ride through our fruit farm on the way to the activities. The Back Forty includes a ten acre corn maze, a six acre pumpkin patch and a large play area where you will find the pedal tractor racing, giant slides, apple cannons, a sand box, a hay pyramid, jumping pillows, zip lines and many photo opportunities. The Back Forty has acres of pumpkins for you to wander though in search of the perfect pumpkin for your jack-o-lantern.
Mondays – Fridays from 3:30 P.M. – 8:45 P.M. with the last wagon leaving the barn at 7:30 P.M.
Saturdays from 10:30 A.M. – 8:45 P.M. with the last wagon leaving the barn at 7:30 P.M.
Hayrides begin September 22, 2018 running thru October 30, 2018 Hayrides leave every 15 minutes.
Special hours for October 18th and 19th will be from 10:30 A.M. – 8:30 P.M.
Special hours for November 3rd will be from 10:30 A.M. – 6:00 P.M.
All Day Admission is $9.00 per person.
Admission includes… a wagon rides to the “Back Forty” and back to the Barn, corn maze, pumpkin patch, apple cannons, giant slides, race tractors, hay pyramid, tractor train, giant sand box, jumping pillows, and zip lines. Children under the age of two are free for the ride and all activities.
All people that have paid full admission will be able to buy one pumpkin that is any size for $5.00.

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Rank: 27
Score: 57.287643
Retrieved Text: A full list of the RPSI's wagons, tenders and cranes.
81 GNR Brake Van 20 ton Whitehead Grey 01/12/1945 1985 In traffic Major overhaul by 'Youth' team.
504 GNR Guinness Grain Van 20 ton Whitehead Grey 1911 1965 Under restoration HLF restoration project.
602 CIÉ Tank Wagon Whitehead Black 1949 1965 Museum exhibit Irish Shell wagon restored with NIMC grant.
697 NCC Brown Van 10 ton Whitehead Brown 1949 1980 Museum exhibit 4 wheel, vacuum fitted. Restored by NI Prison Service, Hydebank.
788 GNR Parcel Van (P2) 10 ton Whitehead Brown 1934 1979 Poor Vacuum fitted.
1325 NCC 4 Plank Wagon Whitehead Grey 1942 1969 Poor Floor planks missing.
3076 NCC Hand Crane 6½ ton Whitehead Black 1943 1979 Good Cowans Sheldon. General yard duties.
3169 GNR Steam Crane 15 ton Whitehead Red 1912 1980 Poor Cowans Sheldon self-propelled crane. Requires overhaul.
23574 CIÉ Brake Wagon 20 ton Whitehead Grey 1950 1983 Poor PWD 11-82.
23962 CIÉ 4-Wheel Well Wagon 20 ton Whitehead 1962 2016 Good Numbered 651A in departmental service.
C355 NCC 3 Plank Wagon Whitehead 1942 1979 Fair Pyramid ends with cover bar.
C69 NCC 4 Plank Wagon Whitehead Red 1969 Poor Floor planks missing.
PW1 RPSI Atlas Trailer Whitehead Flat bed added to B4 bogie as trailer for Atlas road/rail excavator.
R2 CIÉ Rail Wagon 30 ton Whitehead Black 1958/1998 1985 Fair Ex open standard 1469. Shortened and strengthened for use as transporter wagon for narrow-gauge stock.
R3 CIÉ Rail Wagon 30 ton Whitehead Black 1958/1998 1985 Poor Ex open standard 1483. Decking smashed.
GNR 4 Plank Wagon Whitehead Red Poor Carrying steam crane jib.
GNR Boiler Wagon Whitehead Brown

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Rank: 28
Score: 57.215244
Retrieved Text: "I'll fix you're Little Red Wagon" "We've seen a lot of Radio Flyer go karts, but this has to be one of the coolest!" "View topic - Radio Flyer Go Kart For Sale" "looks sick, but I don't see any suspension." "Another hot rodded Radio Flyer" See more. Classic Red Wagon. Backyard Toys For Kids Little Red Wagon Retro Toys Radio Flyer Wagons Popular Toys Walmart Radio Kids Ride On Ride On Toys... My Little Red Wagon Children's book inspires many different people in many different ways. It's ever y little girls and little boys dream to feel PROUD of themselves. This story is about counting 1-5, learning 5 colors and how to grow and take care of a beautiful little garden all on their own.
"It's Your Little Red Wagon" is an absolute must-have for anyone's self-help collection. As a psychologist in clinical practice, I am frequently asked to recommend books to complement the work being done in …... For Keena Bryant, also known as Mrs. KEG Media, there’s nothing typical about her latest SEMA build, a 2015 GMC Yukon XL dubbed the Little Red Wagon.
Posted on April 10, 2013 by Little Red Wagon Train Here’s a quick video of the Little Red Wagon Train as a “work truck” just prior to embarking on a 142-mile walk from Sanderson, Texas to Boquillas, Mexico, at the southern tip of Big Bend National Park.
The ‘little red wagon’ idea was proposed to me by Richard Barbaras. The RC truck idea was proposed with a truck to experiment with by

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Rank: 29
Score: 57.08713
Retrieved Text: Build a wagon as a team to donate to charity!
Solve challenges together, and come out with a little red wagon to brighten a child's life. Several companies offer the materials and leadership for this approach to team building.
Corporate Teams' "Wagons West" delivers intensely collaborative, active, problem-solving challenges that require strategic thinking and effective communications. Each team is also supplied with decorations to package the wagon and to create a greeting card for the recipient child. A surprise at the end of the event results in "not a dry eye in the house."
In Magnovo Training Group's Wagon Builders activity, your team assembles a red wagon, and fills it with a variety of gifts depending on the chosen charity. The team tackles several problem-solving challenges that emphasize the importance of working together to overcome obstacles! Participants learn this is not a competition but an alliance of team member strengths to accomplish the wagon assembly.

================



======= Instance Index 1925 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are red wagon or blue wagon ):

The full box is harder to move because it has greater mass and therefore greater inertia.


Sally is pulling two wagons. The red wagon is full of sand, and the blue wagon is empty. The wagon that will be easier to pull is the red wagon or blue wagon?

Target Text: blue wagon

#### Retrieved Documents ####

Rank: 0
Score: 71.361084
Retrieved Text: Having a wagon as a child is one of my fondest childhood memories. Buying your child a wagon will not only put a smile on their face but yours as well. You will make countless memories with your children as they grow up and if you own a wagon it will be part of those memories. There are so many great uses for a wagon. They are a great alternative to using a stroller and are loads of fun. They can be used for long walks around your neighborhood and parks. Some wagons can not only be used for recreational purposes but practical purposes too like hauling backyard materials. They even have wagons made just for the beach. Once you own a wagon, you will use it all the time. Since there are so many different types of wagons, we composed this list of the top 6 wagons for kids. We made our choices by doing product research, reading countless reviews online, looking at star ratings on Amazon.and personal experiences. All of the wagons listed below have a 4-star rating and up.
This classic style wagon is designed to have a smooth ride on all different types of terrain. It has a steel body with natural wood sizes. The high wooden stake sides let your child sit comfortably and safely inside while keeping their hands and fingers secure. It’s 10″ rugged rubber tires can easily be filled with air to keep that nice and smooth ride. Extra long handle for easy pulling. The handle also folds under

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Rank: 1
Score: 68.48837
Retrieved Text: Do you have happy childhood memories of pulling around, or being pulled around in a wagon? Do you want your little ones to have the same experiences to treasure for life? With so many to choose from which are the best kids wagons?
My little ones love their red wagon. They pull their toys around in it when we’re at home and enjoy riding in when we’re out.
I have to admit I love it as well. It’s so much easier to have the kids, all their stuff, and anything I need in one place. Much easier than a stroller with kids inside, or walking alongside, and bags hanging from the handles.
Let’s look at why you should get a wagon, what to look for, and our top 10 picks.
We ♥︎ honesty! Mom Loves Best earns a commission through the hand picked links on this page at no extra cost to you.
Use the links above to check the latest prices or read our in-depth kids wagon reviews below.
Why Do I Need a Push Wagon?
How Do I Choose a Push Wagon?
These versatile workhorses offer a great alternative to a stroller and give you the chance to carry things easily. You can get the kids, the picnic, some of their toys and more in some wagons.
Kids also love wagons, whether it’s pulling friends around or sitting inside with a friend or sibling. Even the little ones can have their own wagons.
You can take a wagon along when you head to the beach, the park, on the trail, around the neighborhood for

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Rank: 2
Score: 66.658516
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Rank: 3
Score: 64.66206
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Rank: 4
Score: 64.49822
Retrieved Text: The red pull-along, ride-in wagon has become synonymous with the joys of childhood.
This isn’t surprising as children like to be pulled along by their family members and friends while riding on these wagons, as well as pulling along their precious possessions. The wagon is such a staple of childhood that parents and grandparents today have fond memories of it.
Of course, the physical and mental benefits that come from playing with these wagons cannot be dismissed either. Child psychologists agree that the proper and regular use of wagons among children strengthens their muscular, social and cognitive skills, especially during cooperative play.
Parents agree that just seeing their children enjoy their wagons is sufficient reward for the time and money spent on buying these toys.
Here are our top 12 picks for the best kids’ wagons. Choose based on your budget, as well as your kid’s age, weight and preferences to get the best bang for your buck.
The Step2 brand is known for the versatility of its products in the sense that they “grow” with your kids and/or have multiple uses. This is true for this All Around wagon, which has two main uses: first, as a pull-along wagon with and without a canopy; and second, as a flatbed or table for your little ones to enjoy.
As a pull-along wagon, it has comfortable seats for your kids to sit on while being pulled along. They can be installed or removed depending on their preference.
As a flatbed or table, the seats can be flipped over to transform into a larger flat

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Rank: 5
Score: 63.496895
Retrieved Text: Since 1917, kids everywhere have loved riding their Radio Flyer trikes and wagons.
Radio Flyer Wagon Umbrella Toy Kids Play Children order black friday online Radio Flyer Wagon Umbrella Toy Kids Play Children Compare prices for for best toy websites.
Radio Flyer also produces scooters, tricycles, bicycles, horses, and ride-ons.
Like all Radio Flyer wagons, this one has heavy axles to handle a lot of weight,.Radio Flyer is the official maker of the little red wagon, tricycles and other safe.Save up to 15% with these current Radio Flyer coupons for October 2017.
Get free Radio Flyer coupon codes, deals, promo codes and gifts.Radio Flyer is now giving away one toy changed each day during limited period with checkout its calendar for all the great toys.
Get Carts And Wagons coupons,. and Wagons. garden cart wagon carts wagons wheelbarrows wheelbarrow wheel barrow radio flyer red.
Radio Flyer is the official maker of the little red wagon, tricycles and other safe, quality toys that spark imagination and inspire active play.
The popular Radio Flyer Pathfinder Wagon combines durability, comfort,.
Important Information on Product Recalls Radio Flyer Walker Wagon.
Now save with free Radio Flyer coupon codes and discount promo codes to Radio Flyer at ETcoupons.com.Radio Flyer Coupon Code Free Shipping was written by admin yesterday, more image and video.Radio Flyer is an American toy company best known for their popular red toy wagon.
Well, in this article I will show you two nostalgic wagons that your child will love.RadioFlyer.com is the official source for the latest Radio Flyer promo codes, coupons and special offers. Now Until July 4th,

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Rank: 6
Score: 62.318256
Retrieved Text: Summary: The FLA wagons are low-floor container carriers, capable of accomodating the increasingly popular �high-cube� ISO containers within the British loading gauge. Formed into 2-, 3-, 4- or 5-wagon sets, they can be seen mixed in with other wagon types on Freightliner services across the country.
History: The global adoption of ISO standard containers revolutionised international freight transport, allowing cargoes to be handled and transported more easily and quickly. However, although the standard rigidly specifies the container width and length, the height is less constrained. Early ISO containers were 8ft or 8ft 6in tall, these later being joined by 9ft and 9ft 6in tall �high-cube� containers. The Freightliner wagons built in bulk by BR in the 1960s and 1970s were able to carry 8ft tall containers and, following gauge clearance enhancements, 8ft 6in boxes on most routes. But for the taller boxes, which were becoming increasingly popular with shipping companies, new designs of wagon were required.
The FLA was the first successful type capable of carrying �high-cube� containers but it is worth mentioning some of the other designs that preceded it.
In the early 1980s, The Standard Railway Wagon Company was proposing a 2-axle well wagon rather like a stretched Lowmac (an artist�s impression was published in the book �British Railfreight Today and Tomorrow� by Geoffrey Freeman Allen, published by Jane�s in 1984). This would be able to carry 20ft long, 9ft tall boxes in the central well, or 30ft long, 8ft 6in tall boxes across the two end platforms. The wheelbase of almost 9 metres would have been

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Rank: 7
Score: 62.284103
Retrieved Text: . . . and babies make four.: Happy Memorial Day!
We live in a town that happens to love parades. There is one for St. Patrick's Day, one for the Fourth of July, one for pets and, the granddaddy of them all, one for Memorial Day.
This year the girls got to be in the parade instead of just sitting on the curb watching the parade go by. We decorated their wagon, bought candy to give out to the kids along the parade route and met at the parade start along with high school bands, military bands, fire engines, politicians and scout troops. We were marching with the twins club I belong to so we were joined by other "doubles" also in strollers or wagons.
When it was finally our turn the girls asked about 10 times if we were "IN" the parade and then started waving like seasoned parade pros.
Then they wanted out of the wagon to hand out candy.
And I let them out.
You'd think I was new at this.
It's not easy -- actually it's nearly impossible -- to manage two children trying to slowly hand out candy, while flatly refusing one one bit of help, while also pulling a red-white-and-blue-emblazoned wagon. It is especially difficult when the 75-piece band behind you is literally about to run you over. And once out of the wagon Kenna never wanted in again. So, I got Michal back in and carried Kenna for the entire rest of the parade.
We'd arranged for Eric to meet us mid-route and I was so happy

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Rank: 8
Score: 62.10857
Retrieved Text: folding wagon utility cart everyday sports folding wagon utility cart collapsible wagon utility all terrain outdoor beach sports fold up collapsible wagon utility all terrain outdoor beach sports fold up top best wagons.
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Rank: 9
Score: 61.922077
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Rank: 10
Score: 61.647057
Retrieved Text: Published 04/23/2019 06:08:39 pm at 04/23/2019 06:08:39 pm in Collapsible Cloth Wagon.
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Rank: 11
Score: 61.283363
Retrieved Text: Improper wiring can activate the wagon’s motor unintentionally, posing an injury hazard.
Radio Flyer at 800-621-7613 from 8 a.m. to 5 p.m. CT Monday through Friday or online at www.radioflyer.com and click “Product Recalls” for more information.
This recall involves Radio Flyer’s eWagon children’s battery-operated electric wagons. When force is applied to the wagon’s electric handle, the motor activates to power the wagon. The foldable wagon is constructed of red and gray fabric and a steel frame and measures about 41 inches long, 25 inches wide, and 42 inches tall. The wagon has a removable canopy, two seats with seatbelts, four cup holders, a storage pouch, a removable battery and a telescoping handle where the power button is. The Radio Flyer logo is printed on each side of the wagon. Only wagons with model number 3912/3912A are included in this recall. The model number can be found on the handle warning label located near the pivoting joint.
Consumers should immediately stop using the recalled wagons and contact Radio Flyer for a full refund.
The firm has received two reports of the wagon’s motor activating unintentionally. No injuries have been reported.
Toys “R” Us stores nationwide and online at www.radioflyer.com and www.toysrus.com from August 2017 through January 2018 for about $350.
Radio Flyer Inc., of Chicago, Ill.

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Rank: 12
Score: 60.794235
Retrieved Text: BR Olive 12T Pipe Wagon.
BR Baux 12T Pipe Wagon.
GWR Shunters Truck BR Black 'Margam Jn' Weathered.
BR VDA Box Van weathered.
BR YGH ‘Seacow’ Bogie Hopper BR Departmental Olive Green weathered.
12 Ton Southern 2+2 Planked Ventilated Van LMS Grey.
46 Tonne RNA Nuclear Flask Barrier Wagon.
Conflat Wagon BR Bauxite (Early) With ‘Speedfreight’ Ventilated BA Container.
3 Plank Wagon LMS Grey.
BR 3 Plank Olive Green.
BR 20t Brake Van ZTO.
16 Ton slope side mineral wagon pressed side door in MOT brown.
13 Ton Steel Sand Tippler Wagon BR Departmental Olive Green.
8 Plank Fixed End Wagon 'William Harrison'.
Coal Trader's Triple Pack, 5 Plank P/O Wagons Weathered.
Coal Trader's Triple Pack 7 Plank Private Owner Wagons Weathered.
7 Plank End Door Wagon 'Park Lane Wigan'.

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Rank: 13
Score: 60.77068
Retrieved Text: The Tigo S is a compact loader wagon series with a controlled feed unit, Lely provides the correct model for any operation with 3 (classic models) or 5 swing arms. The high performance chopping unit can be fitted with up to 33 knives, which are easy to replace. The low loader models with low centres of gravity and wide tracks appeal to users due to their safe operation on slopes and their low empty weight.
The new Tigo S Profi series has been developed especially for the modern, high performance agricultural business. The camless pendulum pick-up with five rows of tines ensures clean pick-up of crops. The feed unit is powered by a heavy duty gear drive and has five stable feed forks to transfer the crop smoothly and extremely gently into the wagon. The Tigo S Profi series is available in four wagon types from 40 to 70 m³ and two discharge wagon models.
The Tigo R models are loader wagons for medium to large agricultural businesses, which produce their own silage. They are robust and provide increased capacity. These wagons are fitted with a 31 knife 800 mm chopping rotor and a 5 tine bar non-steered pick-up. The configuration of these wagons is simple but it boasts high capacity and ease of operation.
The Tigo R Profi models are used by agricultural contracting companies. The unique non-steered pick-up features 7 tine bars; the high performance rotor is 800 mm in diameter and has 7 spiral-shaped tines on each bar. 40 chopping knives cut crops to 37 mm.

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Rank: 14
Score: 60.658215
Retrieved Text: In 1976 Queensland Railways placed an order with Commonwealth Engineering at Salisbury, Brisbane, for 125 HWO class drop-sided open wagons. They were to be the last open wagon type purchased by QR, and the largest drop-sided open wagon to be operated on the Queensland system.
Running numbers for the 125 members of the HWO class were from 39480 to 39604. All were delivered between August 1977 and March 1978. When ordered in 1976, they cost $30,139.00 each.
The drop-sided door design allowed for easy loading of many styles of general goods not requiring a box wagon. When loaded with palletised goods, they were often tarped prior to dispatch, and lashing rings were provided for tarping along the side of the wagon below the doors. The floor of the wagon was a composite design of steel and hard wood timber, with the timber slightly raised to ensure the cargo was resting on wood when loaded. The raised ends of the wagon also featured timber on the inside face.
When delivered, the HWO wagon featured steel doors with pressed vertical ribs for strength. From the late 1980's, the HWO fleet went through a rebuild and refurbishment program which included replacing the original doors with a new pattern that was much stronger. The new pattern door featured a flat plate steel inside face, with steel box section framework on the outside. During this rebuild program, a data plate was also fitted below the wagon body line to carry the individual wagon number and information. From the early 1990's, buffers were progressivly removed

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Rank: 15
Score: 60.4799
Retrieved Text: Vintage Dan Patch Horse Steel Coaster Wagon RARE!!!
Look here to find old Radio Flyer wagons, vintage red wooden wagons, tin wagons, antique Playskool wood toy wagons and many more appearing on sale daily!
Vintage Playskool Wooden Dairy Wagon Pull Toy 6 Milk Bottles With Chocolate!!!
RARE VINTAGE HOLGATE WOODEN WAGON PULL TOY - FREE SHIPPING!
Vintage Speedway Series Little Red Wagon - New In Box - Free Shipping!

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Rank: 16
Score: 60.047047
Retrieved Text: Roll out the red wagon…this little fox is going to market! We made tissue box wagons, grabbed our shopping lists, and headed to the market to play a vegetable matching game. Sporting fox ears and tails, naturally.
We read Red Wagon by Renata Liwska (Philomel Books, 2011). Lucy the fox has a new red wagon and a big job to do. She must take her mother’s list to market and buy some groceries. Lucy sets off with her animal friends, and while they do eventually bring the veggies home, they also have adventures as the red wagon transforms into a boat, covered wagon, caravan, train, rocket ship, and construction vehicle. After Lucy’s big day, the red wagon serves one final purpose…a place to take a nap!
We’ll begin with the little red wagon! Cut a large tissue box down to 1.75″ inches tall, then wrap with red paper. You can go with our standard wheel assembly (instructions here), or hot glue shortened paper towel tubes the bottom of the box to suggest wheels, and drag the wagon on the fixed tubes.
For the wagon’s handle, you can use a simple pull string, or you can make a drinking straw handle like we did. To make our handle, thread an 16.5″ piece of string through a drinking straw. Pull 1″ of string out of the straw, fold it down, and tape it to the side of the straw. The other end of the string should extend, unattached, from the opposite end of the straw.
Next, cut two notches the center of

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Rank: 17
Score: 59.975006
Retrieved Text: The famous Radio Flyer 2700Z Pathfinder Wagon offers classic durability, fun, and safety that will definitely please both kids and adults. This high-quality wagon has cup holders and flip-top seats that your child can use to lean back on. The seats can also be laid back to store personal items in the wagon as well. It comes with safety belts, wide storage space, and a long handle for hauling. It’s designed for kids ages 1 to 2 years and above. The Radio Flyer Pathfinder Wagon also includes axles in the front designed for extra safety.
Amazon.com (check current discounted price with free shipping) seems to have the best price for it. We also love their customer service as well.
This wagon is made of durable plastic with the classic red color of Radio Flyer. Setting up the wagon can easily be done with the illustrated instructions they provide. Amazon has also made this package Frustration-Free so it’s very easy to open and start using the wagon pretty quickly.
This wagon is made of durable plastic, easy to haul, and has a front axle with security features.
The tires are Dure-Tred, designed for an easy, comfortable, and safe ride.
Seats can be folded up or down.
Includes cup holders, alternative storage space, and two seats with seatbelts.
Branded by Amazon as Frustration Free Packaging.
On average, customers rated Radio Flyer Pathfinder Wagon 4.5 out of 5 stars on Amazon. Customers really like the hard and sturdy plastic build of this wagon so that the wagon will last a long time through all the bumps and

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Rank: 18
Score: 59.873154
Retrieved Text: Articles About Our Products and How They Work.
The Problem With Red Wagons.
What’s the problem with the standard "little red wagon”? Well, it depends on what you plan to use it to do. This old reliable product in either plastic or metal has withstood the test of time—it certainly works and transports cargo well. The problem is that the standard red wagon won't fit in most small car trunks as the wheels do not fold like a Pancake Flat wagon's foldup, patented wheels. (Try stacking two red wagons, for example.) The Pancake Wheel technology, with its compact, folding wagon and cart products provide the cargo benefits of a traditional wagon or cart, with the added benefit of easy compact, foldup storage. Only after Pancake Wheel invented the Pancake (R) folding wheel and related handle technology did many wagon and cart manufacturers take notice of consumer's desires for fold flat wagons and carts, but no other solid base wagons or carts compare to the world thinnest Pancake flat wagons and carts in terms of how flat they fold up. We have begun licensing our fold flat technology to savvy manufacturers so look for our products for sale! During 2011, Pancake Wheel licensed our folding handle designs to Radio Flyer as Radio Flyer recognized that consumers desire to fold wagon handles out of the way. Our fold flat handle provides holding positions for the folding handle so it won't drag on the ground, and even better, the handles folds flat right inside the wagon when not used.
Jogger Truly Folds

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Rank: 19
Score: 59.266243
Retrieved Text: The Owners of Werner Wagon Works, Connie and Don Werner, stand in their Horton shop. The couple are thrilled to have one of Don’s wagons chosen to be in President-elect Barack Obama’s Inauguration Day parade on Jan. 20.
Horton ? For years, Don and Connie Werner have led the Lawrence Old-Fashioned Christmas Parade down Massachusetts Street in their covered wagon.
On Jan. 20, one of Don’s handcrafted wagons will parade down a much bigger street: Pennsylvania Avenue.
“We are just elated, just plum tickled about that,” said Don, who owns Horton-based Werner Wagon Works along with his wife.
This fall, Don was building a custom chrome hitch wagon for the McCrossan Boys Ranch in Sioux Falls, S.D. He was about three-quarters of the way done when he received a call from the ranch’s admissions director, Troy Geis, who asked how the project was going.
“He said, ‘I think we need to step it up a little bit, we might be picked to go to the inaugural parade,'” Don said.
The deadline was to have the wagon finished by the beginning of November so photos could be taken of the metallic green wagon.
“I said, ‘We will be cutting her thin, but I think we can make it,'” Don recalled.
Two weeks after the wagon left the Werners’ shop, they learned it would be in the Inauguration Day parade.
“I mean it’s just a privilege. This is historical-type stuff,” he said.
The McCrossan Boys Ranch, which works with at-risk youths in South Dakota, was one of about 1,400 organizations to submit entries for the parade. Only about

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Rank: 20
Score: 58.93867
Retrieved Text: Legacy of legendary St. Louis wagon builders endures.
Variations in condition, originality and completeness can affect resale values of vintage wagons. This Linstroth wagon not only benefits from vibrant original paint and sound wheels, but also retains its original seat and folding end gate.
This early color image shows an artist's rendering of the Luedinghaus "tower of wagons" displayed at the 1904 World's Fair in St. Louis.
Color advertising was expensive: It was used sparingly by wagon makers. This Luedinghaus image was part of a promotional flyer outlining the brand’s advantages.
Colorful and attractive promotional items such as this Gestring wagon watch fob garnered plenty of attention while helping reinforce the desirability of the brand.
This Weber & Damme wagon is being unloaded at a local train station. Period photography helps us better understand how early vehicles were used while often eliminating misconceptions and stereotypes.
Located at the Santa Ynez Valley (Calif.) Historical Museum, this Gestring wagon features a 43-inch box width, St. Louis seat risers and contoured woodwork on the spring seat. The third set of sideboards (top box) are original. Designed to slope downward from a near 7-inch height in the front to just over 2 inches at the back of the wagon, they are extremely rare.
Many of St. Louis' early wagon makers were positioned near steamboat landings. Such areas were a hub of activity, where supplies were unloaded and others were shipped west.
These rare, original letters from Joseph Murphy date to 1883 and 1887. Each has helped solidify his reputation for expert woodwork and high-quality vehicles.
Wagon makers often used

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Rank: 21
Score: 58.43678
Retrieved Text: One of the ways that the N Gauge Society has been celebrating its 50th anniversary has been to team up with Peco to produce a selection of exclusive wagons from their well-established range.
The 50th anniversary marks a significant milestone for the Society and for N Gauge itself. Few can deny that without the product support from Peco over most of that time, N Gauge (and the Society) would not be where it is today. Peco’s founder Sydney Pritchard was member number 2 of the Society, a membership number that is still held by Peco to this day.
The Society has made a varied selection of interesting wagons to hopefully cater for most members. While they are all equally appealing, pride of place perhaps goes to the 7 plank coal wagon for G Simmons, as the eagle-eyed will note that it is number 50. The prototype was a GER registered 1909 built 7 plank wagon without end-doors, exactly as per the Peco wagon.
The all-steel Austin Motor Company wagon is well-suited to the Peco model, having side and end doors. Built in 1928 it is possible that they were only used internally, although they were registered by the LMS, and probably carried coal from North Staffordshire collieries to the Longbridge factory.
The Peco ‘salt’ wagon is very distinctive, and for a change, the livery of Tollemache is for the carriage of pulverised coal. This wagon has been produced in other scales but never in N Gauge. The prototype wagon was built in 1920 and converted for pulverised coal in 1926

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Rank: 22
Score: 58.418747
Retrieved Text: Do you love to take walks with your little kids until they complain they’re tired after you’ve only gone one block?
How about walking with more than one small child? It can be frustrating for parents who want to take walks, attend outdoor art fairs, camping or countless other activities. A kid’s wagon can make all of that so much easier, plus your kids will love to play in the kids’ wagon.
Choosing the best wagon for kids is a big decision. You need to consider safety factors as well as quality and how well the wagon works. Here we have examined 10 of the best wagons for kids and the best wagons for toddlers in 2017.
Little Tikes presents this study kids wagon with QuietRide wheel technology for a less noisy ride. It comes with a removable umbrella to provide a shady ride, a cooler to transport cold drinks and snacks, and drink holders.
The sides are removable so you can convert it into a bench that even an adult can sit on. The wagon handle can be folded underneath for easy storage when not in use. Seatbelts keep your children safe when they’re being pulled along. When the kids are not playing with it, you can even use it to pull along supplies for your yard or gardening projects.
This deluxe wagon really has it all for a relaxing ride and converts to a great place to sit and relax. With the cooler, it makes snack time a breeze. It’s made in the USA and customers absolutely love it.

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Rank: 23
Score: 58.134056
Retrieved Text: Little Adam sat up and looked around. He saw his stepmother and she didn’t look good. Adam became scared and went over to her and got a rag and wiped her face. “Mom! Mom! Are you okay, Mom! Pa!” he screamed, “go get her some help, she is hurting so badly!” Inger was in the middle of a contraction and was unable to respond to the child; the contractions were about a minute apart.
When she could get a deep breath, she looked at Ben and yelled, “Go Now! Go get Sally; she has had the most experience since she has six children of her own. She will know what to do!” Ben quickly turned and jumped out of the wagon and went over to the Carver wagon. He knocked, loudly.
Sally was praying that this child would not tear Inger badly but she was sure that he would be big and she could only do so much. Inger began her pushing, it took about six good pushes and her son entered the world screaming. He was big! “Oh, Inger,” squealed Sally, “he is beautiful! Big, pink and beautiful!” She placed the newborn on Inger’s’ stomach and prepared to cut the umbilical cord. As she turned around, she saw that Ben had placed the boiling water on a ledge with the knife inside and she quickly grabbed it and cut the cord. At that time, she tied the cord and began to wait for the next set of contractions to deliver the placenta. With this complete, Sally wrapped

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Rank: 24
Score: 57.862972
Retrieved Text: LARGE CAPACITY: Large load folding wagon cart outside dimensions approx: 39.37"Lx21.65" Wx25.98"H. The collapsible utility wagon cart inside size is 31"Lx17.7" Wx10.6"H. Ground to the top of the handle:38.6". Two cups are not included.
WEIGHT CAPACITY: The wheel of the canvas wagon is 4" wide and 7" in diameter, the utility wagon collapsible heavy duty frame allows loads up to 300lbs. The spacing of the wheels can be adjusted randomly to suit different road surfaces. The folding wagons cart fabric material 600D Polyester, and it is removable for easy hand or hose washing, camping beach wagon cart frame material steel, the beach outdoor utility wagon cart sturdy black steel frame is more stable.
360 DEGREES BEACH WHEELS AND ADJUSTABLE HANDLE: The folding wagon come with heavy duty 7"x 4" thick rubber wheels - rotates 360, the spacing of the wagon cartwheels can be adjusted randomly to suit different road surfaces. Telescoping handle provides an easy control on most terrains, camping wagon cart handle can be adjusted height and adapted to the different height person push the cart.
EASY TRANSPORT: Sets up in Seconds, No Assembly Required! Folding into the carry bag for convenient storage. Small enough to fit in the closet, on the wall or in the trunk of any standard car. Folding utility wagon cart is perfect for transporting shopping, on family outings or as a goods trolley, and great for trips to the beach sand, garden, park, camping, outdoor sporting events, or just move things.
SATISFACTION GUARANTEE: Refund or replacement within One Year are guaranteed! Provide you a

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Rank: 25
Score: 57.74872
Retrieved Text: 1) All demands for despatch of goods in wagon loads will be entered in the Wagon Demand/Priority Register maintained at the stations or goods sheds open for booking of goods in wagons loads. The signature of the sender or his representative will be taken in the appropriate column provided in the register after duly filling in all the other columns. The prescribed registration fee will have to be paid by the sender or his representative at the time of registration of demands for wagons.
2) A forwarding Note duly filled in should be tendered by the sender at the time the goods are physically brought into the Railway premises.
3) (a) A limit may be placed by Railways on the quantity of goods permitted to be registered at a time by one indentor.
(b) When booking is restricted to a particular station or by a particular route, full details regarding the restrictions will be exhibited at the station.
(c) When limits are placed on the Registration of goods in the manner indicated above, full details thereof will be exhibited at the Stations.
4) When Booking is restricted to a particular Station or a particular Route, full details regarding restrictions will be exhibited at the Station.
a)Traffic in any commodity offered by Platinum & Gold card holder from their siding.(If they cancel their indents under any of the circumstances notified in Rule 201(15) of Goods Tariff M.41, Part I, Vol.I an amount equal to wagon registration fee may be collected).
b)Container Traffic Booked by CONCOR.
c)Railway Materials and Stores booked by Railway officials in their

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Rank: 26
Score: 57.558697
Retrieved Text: What better way to enjoy the changing season then by visiting the Barn for a wagon ride to the “Back Forty”. Our wagons takes you on an enjoyable tractor pulled ride through our fruit farm on the way to the activities. The Back Forty includes a ten acre corn maze, a six acre pumpkin patch and a large play area where you will find the pedal tractor racing, giant slides, apple cannons, a sand box, a hay pyramid, jumping pillows, zip lines and many photo opportunities. The Back Forty has acres of pumpkins for you to wander though in search of the perfect pumpkin for your jack-o-lantern.
Mondays – Fridays from 3:30 P.M. – 8:45 P.M. with the last wagon leaving the barn at 7:30 P.M.
Saturdays from 10:30 A.M. – 8:45 P.M. with the last wagon leaving the barn at 7:30 P.M.
Hayrides begin September 22, 2018 running thru October 30, 2018 Hayrides leave every 15 minutes.
Special hours for October 18th and 19th will be from 10:30 A.M. – 8:30 P.M.
Special hours for November 3rd will be from 10:30 A.M. – 6:00 P.M.
All Day Admission is $9.00 per person.
Admission includes… a wagon rides to the “Back Forty” and back to the Barn, corn maze, pumpkin patch, apple cannons, giant slides, race tractors, hay pyramid, tractor train, giant sand box, jumping pillows, and zip lines. Children under the age of two are free for the ride and all activities.
All people that have paid full admission will be able to buy one pumpkin that is any size for $5.00.

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Rank: 27
Score: 57.287643
Retrieved Text: A full list of the RPSI's wagons, tenders and cranes.
81 GNR Brake Van 20 ton Whitehead Grey 01/12/1945 1985 In traffic Major overhaul by 'Youth' team.
504 GNR Guinness Grain Van 20 ton Whitehead Grey 1911 1965 Under restoration HLF restoration project.
602 CIÉ Tank Wagon Whitehead Black 1949 1965 Museum exhibit Irish Shell wagon restored with NIMC grant.
697 NCC Brown Van 10 ton Whitehead Brown 1949 1980 Museum exhibit 4 wheel, vacuum fitted. Restored by NI Prison Service, Hydebank.
788 GNR Parcel Van (P2) 10 ton Whitehead Brown 1934 1979 Poor Vacuum fitted.
1325 NCC 4 Plank Wagon Whitehead Grey 1942 1969 Poor Floor planks missing.
3076 NCC Hand Crane 6½ ton Whitehead Black 1943 1979 Good Cowans Sheldon. General yard duties.
3169 GNR Steam Crane 15 ton Whitehead Red 1912 1980 Poor Cowans Sheldon self-propelled crane. Requires overhaul.
23574 CIÉ Brake Wagon 20 ton Whitehead Grey 1950 1983 Poor PWD 11-82.
23962 CIÉ 4-Wheel Well Wagon 20 ton Whitehead 1962 2016 Good Numbered 651A in departmental service.
C355 NCC 3 Plank Wagon Whitehead 1942 1979 Fair Pyramid ends with cover bar.
C69 NCC 4 Plank Wagon Whitehead Red 1969 Poor Floor planks missing.
PW1 RPSI Atlas Trailer Whitehead Flat bed added to B4 bogie as trailer for Atlas road/rail excavator.
R2 CIÉ Rail Wagon 30 ton Whitehead Black 1958/1998 1985 Fair Ex open standard 1469. Shortened and strengthened for use as transporter wagon for narrow-gauge stock.
R3 CIÉ Rail Wagon 30 ton Whitehead Black 1958/1998 1985 Poor Ex open standard 1483. Decking smashed.
GNR 4 Plank Wagon Whitehead Red Poor Carrying steam crane jib.
GNR Boiler Wagon Whitehead Brown

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Rank: 28
Score: 57.215244
Retrieved Text: "I'll fix you're Little Red Wagon" "We've seen a lot of Radio Flyer go karts, but this has to be one of the coolest!" "View topic - Radio Flyer Go Kart For Sale" "looks sick, but I don't see any suspension." "Another hot rodded Radio Flyer" See more. Classic Red Wagon. Backyard Toys For Kids Little Red Wagon Retro Toys Radio Flyer Wagons Popular Toys Walmart Radio Kids Ride On Ride On Toys... My Little Red Wagon Children's book inspires many different people in many different ways. It's ever y little girls and little boys dream to feel PROUD of themselves. This story is about counting 1-5, learning 5 colors and how to grow and take care of a beautiful little garden all on their own.
"It's Your Little Red Wagon" is an absolute must-have for anyone's self-help collection. As a psychologist in clinical practice, I am frequently asked to recommend books to complement the work being done in …... For Keena Bryant, also known as Mrs. KEG Media, there’s nothing typical about her latest SEMA build, a 2015 GMC Yukon XL dubbed the Little Red Wagon.
Posted on April 10, 2013 by Little Red Wagon Train Here’s a quick video of the Little Red Wagon Train as a “work truck” just prior to embarking on a 142-mile walk from Sanderson, Texas to Boquillas, Mexico, at the southern tip of Big Bend National Park.
The ‘little red wagon’ idea was proposed to me by Richard Barbaras. The RC truck idea was proposed with a truck to experiment with by

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Retrieved Text: Build a wagon as a team to donate to charity!
Solve challenges together, and come out with a little red wagon to brighten a child's life. Several companies offer the materials and leadership for this approach to team building.
Corporate Teams' "Wagons West" delivers intensely collaborative, active, problem-solving challenges that require strategic thinking and effective communications. Each team is also supplied with decorations to package the wagon and to create a greeting card for the recipient child. A surprise at the end of the event results in "not a dry eye in the house."
In Magnovo Training Group's Wagon Builders activity, your team assembles a red wagon, and fills it with a variety of gifts depending on the chosen charity. The team tackles several problem-solving challenges that emphasize the importance of working together to overcome obstacles! Participants learn this is not a competition but an alliance of team member strengths to accomplish the wagon assembly.

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Input Text: Read the passage below and choose the right answer to the following question (choices are increased or decreased ):

In a series circuit, the resistance increases as more resistors are added in series.


By adding twenty more resistors to the series circuit in series, the total resistance of the circuit was increased or decreased?

Target Text: increased

#### Retrieved Documents ####

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Retrieved Text: Parallel Circuits. For one, the total resistance of a Parallel Circuit is NOT equal to the sum of the resistors (like in a series circuit). The total resistance in a parallel circuit is always less than any of the branch resistances. Adding more parallel resistances to the paths causes the total resistance in the circuit to decrease.
Series and parallel circuits. If a wire joins the battery to one bulb, to the next bulb, to the next bulb, to the next bulb, then back to the battery, in one continuous loop, the bulbs are said to be in series. If each bulb is wired to the battery in a separate loop, the bulbs are said to be in parallel.
Total resistance in parallel circuit. Since Vs is the voltage across each of the parallel resistors in above figure,by Ohm’s law I=Vs R: The term Vs can be factored out of the right side of the equation and canceled with Vs on the left side,leaving only the resistance terms.
Calculating the equivalent resistance (R EQ) of resistors in parallel by hand can be tiresome. This tool was designed to help you quickly calculate equivalent resistance, whether you have two or ten resistors in parallel.
In series the total resistance simply equals the sum of the resistors. In parallel, the inverse of the total resistance equals the sum of the inverse of each individual resistor. Therefore, you will not be able to calculate total resistance in a parallel circuit if you only know the sum.
Equivalent Resistance. In the same manner, the presence

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Retrieved Text: 22/02/2017 · Parallel Circuit With 3 Resistors Inspirational How To Calculate Series And Parallel Resistance With Cheat Sheets. Parallel Circuit With 3 Resistors Inspirational How To Calculate Series And Parallel Resistance With Cheat Sheets... Any electrical circuit can be categorized into three different groups - series, parallel and series parallel. So for example, in the case of DC, the circuits can also be divided into three groups, such as series DC circuit , parallel DC circuit and series and parallel circuit .
13/05/2017 · How can we derive the formula for finding equivalent power in a series and parallel combination of 'n' resistors (with fixed resistance)? Use that formula for the particular combination , in which a particular variable is common to all .... In the series circuit, where the total resistance was the sum of the individual resistances, the total was bound to be greater than any one of the resistors individually. Here in the parallel circuit, however, the opposite is true: we say that the individual resistances diminish rather than add to make the total.
20/09/2013 · An explanation and demonstration of calculating total resistance in a series or parallel circuit. An explanation and demonstration of calculating total resistance in a series or parallel circuit... Resistors in series circuits. When resistors are connected together in series, we can add their resistances together to find the total resistance in the circuit.
Resistors in series circuits. When resistors are connected together in series, we can add their resistances together to find the total resistance in the circuit.

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Retrieved Text: In the left-hand figure in the diagram below, three resistors are connected in parallel with a battery, E. Unlike a circuit in which the resistors are connected in series, the total resistance of the circuit cannot be obtained simply by adding the three resistances together. In the right-hand figure, a single resistor with a value of RTOTAL is used to provide the same load resistance as the three resistors on the left-hand side, and its resistance value will be smaller than that of the smallest of the three resistors in the original circuit. The total current flowing through the two circuits is exactly the same, but in the left-hand version the current will be split between the three branches. The amount of current flowing through each branch will be inversely proportional to the resistance value of its resistor in relation to the total circuit resistance. Note also that the voltage drop across each resistor will be the same, and will be equal in magnitude to the supply voltage provided by E.
To ensure that the correct current flows through each branch of a parallel circuit, a resistor of the correct value must be used in each branch. Note that in real-world circuits, it is not always possible to provide the exact resistance required using a standard resistor value. The options are to use a single standard resistor of approximately the required value, or to use two or more standard resistors in series with a combined resistance that exactly matches the required value. Bear in mind that if

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Retrieved Text: The disadvantage of series connections of cells in this manner, though, is that their internal resistances add. What variables affect the resistance in the wire? What happens to the current in this scenario? Draw a diagram of the battery, label the flow of electrons. So the new current can be found by halving and then halving again the old current of 24 mA. But current is also inversely proportional to the resistance; a halving of the resistance will double the current. Current flows in the direction of the greater emf and is limited by the sum of the internal resistances.
Resistors connected in a series circuit: Three resistors connected in series to a battery left and the equivalent single or series resistance right. Note that each emf is represented by script E in the figure. The current also plays a large part in this equation. Use the Ohm's law equation to provide numerical answers to the following questions: a. Comparing rows 1 and 4 or rows 2 and 5 illustrates that the doubling of the total resistance serves to halve the current in the circuit. This equation indicates the two variables that would affect the amount of current in a circuit.
Reducing those highlights that the last two are in series, and thus can be reduced to a single resistance value for the entire circuit. What happens to the current in this scenario? A certain electrical circuit contains a battery with three cells, wires and a light bulb. For example, if you placed two 6v batteries in your

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Retrieved Text: voltage drop across each series resistor.
powers in each resistor in series.
enough to handle the expected power in the circuit.
Each current path is called a branch.
 A parallel circuit is one that has more than one branch.
that junction (total current out).
junction is equal to zero.
total resistance of the circuit decreases.
What is the total resistance in a parallel circuit with 2 resistors?
Given IT, find I1 and I2!
Circuit Example: How does it work?

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Retrieved Text: In this lab you will be using Ohm’s law to calculate the relationships of voltage, current, and resistance.
Look at the circuit below.
Using Ohm’s law, V = I X R, I = V/R, or R = V/I and calculate the missing values.
Your job is to calculate the amount of current that will get to each lamp given the different resistances below. A calculator may be valuable in this portion of the lab.
For quick solutions I also Google "Ohms Law Calculator" and find many websites that have those calculators readily available.
Notice the schematic of the circuit below and you see a complete circuit with the push of electrons and the pull of protons coming from the positive and negative poles of the battery.
Notice the schematic symbol for a battery with the long and short parallel lines of the schematic symbol and you can also imagine the parallel plates of Alexander Volta’s bits of cardboard soaked in brine, holding and releasing an electron charge. Notice the circle with the loop of wire inside. This is the schematic symbol for a bulb and you can imagine this, as appearing like the filament inside a bulb. You already know the schematic symbol for the resistor the wavy line in the top part of the image below.
1 amp is the same as 1000 milliamps so when you do the math using amps just move your decimal place over 3 places to the right and you will have amps converted into milliamps. Solve the problems below.
You can also calculate how many watts you

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Retrieved Text: Voltage: Voltage is equal across all components in a parallel circuit.
Current: The total circuit current is equal to the sum of the individual branch currents.
Resistance: Individual resistances diminish to equal a smaller total resistance rather than add to make the total.
Let’s take a look at some examples of parallel circuits that demonstrate these principles.
The first principle to understand about parallel circuits is that the voltage is equal across all components in the circuit. This is because there are only two sets of electrically common points in a parallel circuit, and the voltage measured between sets of common points must always be the same at any given time.
Therefore, in the above circuit, the voltage across R1 is equal to the voltage across R2 which is equal to the voltage across R3 which is equal to the voltage across the battery.
Just as in the case of series circuits, the same caveat for Ohm’s Law applies: values for voltage, current, and resistance must be in the same context in order for the calculations to work correctly.
As the total current exits the positive (+) battery terminal at point 1 and travels through the circuit, some of the flow splits off at point 2 to go through R1, some more splits off at point 3 to go through R2, and the remainder goes through R3. Like a river branching into several smaller streams, the combined flow rates of all streams must equal the flow rate of the whole river.
The same thing is encountered where the currents through R1, R2, and R3

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Retrieved Text: 4 Calculate the value of v, i and power dissipated in each resistor.
7 Resistors Components which resist or reduce the flow of current in a circuit are called resistances, the unit of resistance is the ohm (Ω). They are used in circuits to control or limit the amount of current flow in a wire ,and to be a current-to voltage convertor. Resistors in series: R total =R1+R2+R3+R4 Resistors in parallel: 1/Rtotal = 1/R1 +1/R2 +1/R3 +1/R4 The total resistor of a parallel resistor network is always dominated by, and is less than, the smallest resistor.
8 All components connected in series have the same current flowing through them.
Calculate currents passing through each node Verify both KVL and KCL Consider sources of errors in this experiment Put all your results and notes into your logbook! Any questions?
Download ppt "Principles of Computer Engineering: Lecture 3: Kirchhoff’s Laws"
Series and Parallel Circuits Kirchoff’s Voltage and Current Laws Circuits 1 Fall 2005 Harding University Jonathan White.
Analog Circuits Seth Price Department of Chemical Engineering New Mexico Tech Rev. 8/31/14.
Series Circuits ENTC 210: Circuit Analysis I Rohit Singhal Lecturer Texas A&M University.
BASIC LAWS Ohm’s Law Kirchhoff’s Law Series resistors & voltage division Parallel resistors & current division Y -  transformation.
Parallel Circuits ENTC 210: Circuit Analysis I Rohit Singhal Lecturer Texas A&M University.
Chapter 5 & 6 Dr. Farid Farahmand CET 236. Outline Identify a series/parallel circuit Determine the current and voltage in a circuit Determine total resistance.
Electric current and direct-current circuits A flow of electric charge is called an electric current.

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Retrieved Text: 1. What does an electric circuit mean?
A continuous and closed path of an electric current is called an electric circuit. An electric circuit consists of electric devices, source of electricity and wires that are connected with the help of a switch.
2. Define the unit of current.
The unit of electric current is ampere (A). 1 A is defined as the flow of 1 C of charge through a wire in 1 s.
3. Calculate the number of electrons constituting one coulomb of charge.
One electron possesses a charge of 1.6 ×10-19C, i.e., 1.6 ×10-19C of charge is contained in 1 electron.
Therefore, 6 x 1018 electrons constitute one coulomb of charge.
1. Name a device that helps to maintain a potential difference across a conductor.
Any source of electricity like battery, cell, power supply, etc. helps to maintain a potential difference across a conductor.
2. What is meant by saying that the potential difference between two points is 1 V?
If 1 J of work is required to move a charge of amount 1 C from one point to another, then it is said that the potential difference between the two points is 1 V.
3. How much energy is given to each coulomb of charge passing through a 6 V battery?
The energy given to each coulomb of charge is equal to the amount of work which is done in moving it.
1. On what factors does the resistance of a conductor depend?
2. Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source?

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Retrieved Text: NCERT Textbook Solutions are considered extremely helpful when preparing for your CBSE Class 10 Physics board exams. TopperLearning study resources infuse profound knowledge, and our Textbook Solutions compiled by our subject experts are no different. Here you will find all the answers to the NCERT textbook questions of Chapter 12 - Electricity.
All our solutions for Chapter 12 - Electricity are prepared considering the latest CBSE syllabus, and they are amended from time to time. Our free NCERT Textbook Solutions for CBSE Class 10 Physics will strengthen your fundamentals in this chapter and can help you to score more marks in the examination. Refer to our Textbook Solutions any time, while doing your homework or while preparing for the exam.
An electric circuit is a continuous conducting path that consists of electric devices, switching devices, source of electricity, etc. connected by conducting wires.
Concept Insight:- The figure given below is an example of an electric circuit.
The unit of electric current is ampere (A).
1 ampere is defined as the flow of 1 coulomb of charge through a wire in 1 second.
One electron possesses a charge of 1.6 × 10 -19 C, i.e., 1.6 × 10 -19 C of charge is contained in 1 electron.
Therefore, 6.25 x 1018 electrons constitute one coulomb of charge.
If 1 J of work is done to move a charge of amount 1 C from one point to another, then it is said that the potential difference between the two points is 1 V.
Concept Insight:- The amount of work done to move to each coulomb of charge

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Retrieved Text: Q4. With a total resistance of 3300 ohms and a 45 V source, if R3 is 1200 ohms, what will be its voltage drop?
Q5. The ______ determines whether connected resistors are in series, parallel, or series-parallel?
Q6. The polarity on the side of the resistor where current enters is ______. The polarity on the side of the resistor where current exits is ___________.
Q8. –1.2 V, +15 V, and –6 V batteries are connected in series. The magnitude of total voltage is _________.
Q12. If three resistors of 1.5 kilohms, 470 ohms, and 3300 ohms are in series with a 25-volt source, what is the total circuit current?
Q13. Given a series circuit containing resistors of different values, which statement is not true?
A.The current through each resistor is the same.
B.The sum of the voltage drops across each resistive element will be equal.
C.The total resistance is the sum of the value of the resistors.
D.The voltage drop across each resistor is the same.
Q14. With 20 V applied, an 8-ohm resistor is in series with a lamp. When the lamp is removed, what voltage will be read across the lamp socket?

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Retrieved Text: Figure 1. A solderless breadboard, with a few conducting rows and columns highlighted. A solderless breadboard is used to temporarily connect components for test measurements. Wire leads from components are inserted into the holes. See Figure 1. Underneath the array of holes are conducting strips. As the highlighting added to Figure 1 shows, the long horizontal rows at the top and bottom form four separate conducting strips, usually called buses. Similarly, running vertically down the board, are numbered columns, each connected with conducting strips. Thus, R1 and R2 are connected by virtue of their leads both being inserted into column 17. Can you see another pair of resistors on this breadboard that are electrically connected? Note that the board is divided into two halves. So, the top half of column 17 is separate from the bottom half of column 17, as shown by the different highlighting.
Why does adding bulbs make them all dimmer?
We can use a solderless breadboard to connect small light bulbs to a voltage source. A 9-volt battery, for example, makes a bulb burn brightly. When we connect two bulbs in series, however, the pair of bulbs get dim. And if we connect three bulbs, they do not light up at all. See Figures 1, 2, 3.
A voltage V dropping across a resistor R in a circuit with a current I. What happens if you lift up one of the wires in the series circuit? That opens the circuit. What causes a bulb to burn brightly? It's the current! The voltage from the battery

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Retrieved Text: Carbon resistors are arranged in a pattern to form a resistor network.
A resistor network refers to a number of resistors configured into a given pattern. Most often, these networks use resistors connected end-to-end in series; however, a number of variations exist where the resistors are connected in parallel or series-parallel sequences resembling ladders. In all instances, the resistors in these networks act as voltage dividers, which divide the voltage applied to the circuit into smaller amounts. Practically, resistor networks are used to provide fractional supply voltages in various circuits or to perform digital-to-analog and analog-to-digital conversion functions.
Resistors are electronic components that resist the flow of electrical current by dissipating its voltage in a manner called dropping. Simply put, a resistor will drop a percentage of a circuit’s voltage. That percentage is equal to the value of a given resistor, in ohms, when compared to the circuit’s total resistance. For example, a 10-ohm resistor will drop 10% of the voltage in a circuit that has 100 ohms worth of resistance.
If a resistor network has five 1-ohm resistors, placed in series, and a 5-volt power supply is connected, each of the five resistors would drop one-fifth of the 5 volts, or 1 volt each. A resistor network, in this way, can provide fractional power supply voltages to other circuits. Since the voltage drop across any one resistor is equal to that resistor’s value in ohms, when compared to the entire circuit’s resistance, practically any voltage desired that is less than the applied voltage is possible in a resistor

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Retrieved Text: NCERT Solutions for Class 10 Science Chapter 12 Electricity are provided here with simple step-by-step explanations. These solutions for Electricity are extremely popular among class 10 students for Science Electricity Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the NCERT Book of class 10 Science Chapter 12 are provided here for you for free. You will also love the ad-free experience on Meritnation’s NCERT Solutions. All NCERT Solutions for class 10 Science are prepared by experts and are 100% accurate.
What does an electric circuit mean?
An electric circuit consists of electric devices, switching devices, source of electricity, etc. that are connected by conducting wires.
Define the unit of current.
Calculate the number of electrons constituting one coulomb of charge.
One electron possesses a charge of 1.6 × 10−19 C, i.e., 1.6 × 10−19 C of charge is contained in 1 electron.
Therefore, electrons constitute one coulomb of charge.
Name a device that helps to maintain a potential difference across a conductor.
A source of electricity such as cell, battery, power supply, etc. helps to maintain a potential difference across a conductor.
What is meant by saying that the potential difference between two points is 1 V?
How much energy is given to each coulomb of charge passing through a 6 V battery?
Therefore, 6 J of energy is given to each coulomb of charge passing through a battery of 6 V.
On what factors does the resistance of a conductor depend?
Will current flow more easily through a thick wire or a thin wire of the same material, when

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Retrieved Text: Can someone explain how switches work? If you have a switch in a series, what happens to the Resistence, VOltage, and Current if you turn it on or off in series and parallel?
In general an open switch behaves like an infinite resistor and a closed switch like a wire.
An open switch in a series circuit means that no current will flow through it or the rest of the circuit.
A closed switch in series has no effect on anything else.
A closed switch on its own in a parallel branch bypasses the component in other branches and you can ignore those branches.
Think of a switch as a device for introducing a break in a conductor with the ability to reinstate the conductor at will.
An ideal switch will have no resistance when closed and infinite resistance when open.
In this way, when closed, it allows current to flow but adds NO additional resistance to the conduction path and therefore does not introduce any additional voltage drops.
When open, the switch breaks the conduction path and NO current will flow.
In practice however, switches introduce small resistances (0.003 ohm is typical) and depending on the construction will have a maximum current and voltage carrying capability. Small switches may only withstand perhaps a few hundred mA with 50V across the contacts. Others are designed to carry upwards of 30A at 250V (domestic circuit breakers) etc.
With switches in series, all of the switches in the series path need to be closed in order for the conduction path to be created. If any single switch is

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Retrieved Text: The aim of this instructable is not to give you a complete guide on breadboard but to show the basics, and once these basics are learned you pretty much know all you need to so i guess you could call it a complete guide but in a different sense. Anyway i will only be using an led and some resistors to outline how a breadboard works.
Note : a breadboard is a temporary circuit board for testing and prototyping circuits, no soldering is done on the board, this mean it is faster and easier to prototype circuits.
As you can see from the image below a breadboard has lots of holes, this may seem confusing at first but it really isnt. The 2 rows of holes at either end are for power one for positive (red) one for negative (black).
as you can see i edited the picture below to give you an idea of how circuits are completed.
the power strips go horizontally in 5's where as the component strips go vertically also in 5's.
a circuit is completed when all the desired strips form a loop and are all connected sequentially.
if for instance i wanted to put an led in this circuit by its self i would insert one leg into a free hole of the column where the black (-ve) power jumper is and the other in a free hole of the column that the red wire (+ve) is in. This would complete the circuit allowing current to flow from one side of the power source to the

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Retrieved Text: Vault into an Indian (I – current) Restaurant (R – Resistance).
Voltage and potential difference are the same thing and you will often see exam questions using the term potential difference instead of voltage. Voltage is measured in volts, 1 volt = 1 joule per coulomb.
In the circuit below, lamps P and Q are identical. The reading on the ammeter is 3A. The cell shown is 6V. Calculate the resistance of lamp P.
Resistors of `2` ohms and `4` ohms are connected in parallel across a battery supplying `6` volts. Another resistor of `5` ohms is connected in series with the battery. Calculate the total resistance of the circuit and the current flowing through the `5` ohm resistor.
First you must work out the total combined resistance of the two resistors in parallel and then add the third resistor to this to get the total resistance of the circuit.

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Retrieved Text: and ideal conductors, with no assumed resistance, to connect the elements in series.
Consider a typical household electrical outlet as a 120-volt source for the circuit and the light bulbs as resistors in a closed circuit. The wires are assumed to have no resistance themselves and connect each of the light bulbs in a single, closed circuit.
Since there is only one path for current to flow in this series circuit, the current or electron flow must be the same in each segment of the circuit. This means that the current leaving the source is equal to the amount of current through each resistance.
1. The current flow is the same through each element of the series circuit.
2. The combined resistance of the various loads in series is the sum of the separate resistances.
3. The voltage across the source or power supply is equal to the sum of the voltage drops across the separate loads in series.
We can find the voltage drop for each resistor by again applying Ohm's Law, this time to each of the resistors.

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Retrieved Text: As we mentioned earlier, there were 2 types of circuits, SERIES and PARALLEL. We have already gone thru Series. Now we are going to discuss the difference between a Series and a PARALLEL circuit. In the series circuit, all the electricity followed the same path. In our waterflow representation, this meant that all the water flowed through 1 pipe. In PARALLEL circuit, however, there are multiple paths that current can flow through.
Notice that in the picture to the left, that there are 3 different paths which the water can take. All 3 paths have the same incoming pressure, but the flow of some paths can be more restricted than in others.
Parallel circuits in electronics work on the same principle. While there may be multiple paths for the electricity to flow through, the electrical pressure (Voltage) remains the same through all paths.
As you can see from the diagram on the right, there are 4 meters placed in this circuit to measure the current.
Resistance in a parallel circuit can be quite a bit trickier than in a series circuit. It is found by "Reciprocating the Sum of the Reciprocals". Simple. Taking the reciprocal of a number means dividing "1" by that number. The reciprocal of 2 would be 1 divided by 2 or ½. Most modern calculators have a [1/X] button just for this purpose.
So if you take the reciprocals of the values of all of the resistors, which would, of course, give you a bunch of fractions, and add them all up, then reciprocate their sum, you

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Retrieved Text: But we’re better than that.
This article will give you a better breakdown on how to convert 8-ohm speakers to 4 ohms than our initial thought.
Getting your desired impedance the easy way takes a little math, but we promise, this type of math won’t leave you scratching your head.
There are 2 types of connections your circuit can be configured to.
Choosing the right one has caused the debate of parallel vs. series circuits.
The point of telling you this is by knowing which circuit you’re working, you can determine how much, and how to get your desired impedance.
To start, let’s talk about series circuits.
A series circuit is similar to a straight line. A series circuit has more than 1 resistor but only 1 path.
An easy way to tell if you have a series circuit is by turning a resistor off. Once you’ve turned off your resistor, does the whole circuit stop working?
If so, then you’ve got yourself a series circuit.
To find out the total impedance value of your circuit all you have to do is add up all the impedance values.
Once you know how much your impedance is worth, then you’ll know whether you need to adjust or stay where you are.
How do I determine if I have a parallel circuit?
A parallel circuit has many paths for electrons to get from one end to the other. This is the main difference between a parallel and resistor circuit which only has 1 pathway.
To figure out the impedance value of a parallel circuit you’re going to need a calculator.
1/R = 1/R

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Retrieved Text: For the circuit shown on the right, find the current through; the potential across; and the power dissipated in each resistor.
Step 1: reduce the parallel combination.
Step 2: reduce the series combination.
Step 3: add the known current(s) and potential(s) to the circuit, and calculate any unknowns.
For any number of resistors connected in series, the potentials across each resistor are simply proportional to the size of the resistor over the sum of them.
Take the case of three resistors connected in series, as shown in the diagram.
For two resistors connected in parallel, the branch currents are proportional to the resistor in the other branch over the sum of them.
Take the case of two resistors connected in parallel, as shown in the diagram.
First find the potential difference across the parallel combination.
A potential difference of 120V is applied across three resistors (20R, 30R and 10R) connected in series. Find the potential difference across the 30R.
A current of 1mA flows into a parallel combination of 20R and 30R resistors. Find the current in the 20R resistor.
For the resistor combination shown in the diagram, calculate the current through the 6Ω resistor.
Firstly, find the equivalent resistance for the three resistors in parallel.
Check: the equivalent resistance is smaller than the smallest.
Secondly, find the equivalent resistance for the new two top resistors in series.
Thirdly, calculate the branch currents using the opposite resistance over the sum.
Check: the current through the smaller resistor is larger than the current through the larger resistor.
Fourthly, the equivalent resistance of the 12|4|6Ω parallel combination has been calculated as 2Ω.
The total current through

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Retrieved Text: The potential difference across a conductor is directly proportional to the current in the conductor at constant temperature.
Determine the relationship between current, potential difference and resistance at constant temperature using a simple circuit.
State the difference between ohmic conductors and non-ohmic conductors and give an example of each.
for series and parallel circuits (maximum four resistors).
Define power as the rate at which work is done.
Solve circuit problems involving the concepts of power and electrical energy.
Deduce that the kilowatt hour (kWh) refers to the use of 1 kilowatt of electricity for 1 hour.
Calculate the cost of electricity usage given the power specifications of the appliances used, the duration and the cost of 1 kWh.
Solve problems involving current, voltage and resistance for circuits containing arrangements of resistors in series and in parallel (maximum four resistors).
Explain the term internal resistance.
Solve circuit problems, with internal resistance, involving series-parallel networks of resistors (maximum four resistors).

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Retrieved Text: We’re finally starting to get armed with some more useful tools to allow us to understand and design some practical circuits.
Today I’m going to talk about another of Kirchoff’s contributions to circuit theory, Kirchoff’s current law. To beign we need to define something called a node within the circuit. Basically a node is where two or more wires connect to each other.
Now what does Kirchoff say about current? Have a look at the next circuit.
All current’s flowing into any node must be equal to all current flowing out of that node.
By the same law we see that . So . This makes sense, all the current leaving the battery returns to the battery.
Now, you may well be asking how will this help us in designing circuits? I know I was wondering such things when I first learned this stuff. Well, it turns out this is a useful tool in understanding our next topic which is a bit more practical.
It doesn’t take much imagination to figure out why they’re call series and parallel. So why are these two topologies important? That’s what we’re going to look at now.
We’ve seen that we can use Ohm’s law to find unknown voltage, currents, and resistances. Now we’ll use that and Kirchoff’s laws to find something called equivalent resistance. To get an idea of what we call equivalent resistance think of a battery connected to a circuit. Some current flows out of the positive terminal of the battery, I, and that terminal is at some voltage, V. From Ohm’s Law we

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Retrieved Text: Electric resistances can be connected in the electric circuit using two methods which are series connection , parallel connection , Home appliances are connected in parallel , Thus every device can work individually on the potential difference of the source & does not affect the other devices when switched off or at mal-function , also their equivalent resistance becomes very small & does not weaken the current intensity .
Its purpose : Obtaining big resistance from a group of small resistance where the resistance are considered as a connected path of the electric current .
Method of connection : The electric resistors are connected with a battery , ammeter , voltmeter , rheostat and a switch in an electric circuit .
The electric current intensity : When measuring the electric current intensity passing in all resistors we find it equal .
When measuring the potential difference between the ends of each resistor , we find that the total voltage equals the sum of potential differences on all the resistors in the circuit .
Its purpose : Obtaining a small resistance from a group of big resistors where the equivalent resistance is less than the smallest resistance in the group .
It is noticed that the electric current is inversely divided on the resistors such that the biggest part of the current passes in the smallest resistor .
That means that the reciprocal of the equivalent resistance for a group of resistors connected in parallel equals the sum of reciprocals of the resistances .
In the electric circuit connected in parallel thick wires are used

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Retrieved Text: I begin the tutorials by assuming that you have basic knowledge about electricity like current ,voltage, charges etc.
A resistor is an electronic device that offers obstruction to the flow of electric current.
It can be defined as voltage per unit current through a conductor.
The unit of resistance is ohm denoted by W .
It has no polarity (i.e. + and -) like a battery and can be connected either way in a circuit.
The resistance is the value of the resistor in ohm Ω. It can also be in kiloohm (kΩ) or megaohm ( MΩ ).
Hence I = 16mA (mA = milliamp = 0.001 amp) . This is the max. Current that can flow through this resistor.
The resistors are available in 1/8 W, ¼ W, ½ W , 1W , 2W and so on.
As the wattage increases the resistor’s cost tend to increase and they also get bulkier.
Tolerance is the extent to which the resistor value sways from the original value. You may think as to why the resistance value should change from the printed value? Well, we live in a world that is far from perfect and resistors are no exceptions. Their value changes mainly due to the change in temperature.
The tolerance values of commercially available resistors are usually ±5%, ±10% and ±20%, where the value indicates the % drift from the original value.
Three bands that are close together are to the left.
Sometimes, resistor values other than the standard available values are required for a circuit. In such a case the required value is obtained by connecting a

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Retrieved Text: Simple circuits (ones with only a few components) are usually fairly straightforward for beginners to understand. But, things can get sticky when other components come to the party. Where's the current going? What's the voltage doing? Can this be simplified for easier understanding? Fear not, intrepid reader. Valuable information follows.
In this tutorial, we’ll first discuss the difference between series circuits and parallel circuits, using circuits containing the most basic of components -- resistors and batteries -- to show the difference between the two configurations. We’ll then explore what happens in series and parallel circuits when you combine different types of components, such as capacitors and inductors.
You may want to visit these tutorials on the basic components before diving into building the circuits in this tutorial.
Before we get too deep into this, we need to mention what a node is. It's nothing fancy, just the electrical junction between two or more components. When a circuit is modeled on a schematic, the nodes are the wires between components.
Example schematic with four uniquely colored nodes.
Current (indicated by the blue, orange, and pink lines) flowing through the same example circuit as above. Different currents are indicated by different colors.
Notice that in some nodes (like between R1 and R2) the current is the same going in as at is coming out. At other nodes (specifically the three-way junction between R2, R3, and R4) the main (blue) current splits into two different ones. That's the key difference between series and parallel!
There's only one way for the current to flow in the above

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Retrieved Text: Discussion in 'The Projects Forum' started by past me, Dec 14, 2009.
HI guys thanks for your insight and help if some one would be as kind to proof read my answers for my assigment would much be helpfull to me my first page is fill in the right terms or words.
red will be my answer and a couple i dont know i would be open to any help if use didnt mind.
A) A simple electrical circuit consists of conductors connecting the voltage source to the load.
B) A switch is always provided in a circuit to interrupt or isolate the current.
D) An "over load" in a circuit occurs when the current is excessive.
F) When measuring current the multimeter is always connected in Series with the load.
G) In a simple parallel Circuit the Voltage is the same across all components.
H) Resistors connected in parallel have a total resistance value that is less than the smallest resistor value.
I) If 10 resistors, connected in parallel have a value of 5 are connected in series. The total circuit resistance will be ???
J) When measuring D.C currents and voltages the Function or setting of the meter must be considered.
M) A capacitor allows electrical current to flow through it.
N) in a telecommunications network you will find various types of currents, these are both ?? and ??
P) in a telephone circuit you will find a capacitor in the ?? circuit to stop the ?? current flowing in the circuit.
Most of them seem right, but M and O aren't entirely correct, and Im not as

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Retrieved Text: Calculate the total resistance of a circuit by combining resistors in series and parallel.
Calculate the range of possible values of a resistor, given its nominal resistance and its tolerance.
Apply the voltage divider equation to calculate the voltage across a resistor.
Apply the current divider equation to calculate the current through a resistor.
Avoid misapplying the voltage divider equation in circuits with loads.

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Retrieved Text: 101 - Demonstrate an understanding of state, school and OSHA safety regulations.
102 - Practice safety techniques for electronics work.
103 - Demonstrate an understanding of proper fire drill procedures.
104 - Interpret Safety Data Sheets (SDS).
106 - Explain the environmentally-safe disposal procedures for electronicsequipment.
107 - Describe the physiological reaction to electrical shock causes.
201 - Recognize the basic units of Electronic Measurements.
202 - Recognize ISM system of measurement (International Systems of Measurements).
203 - Express numbers in scientific Engineering notation.
204 - Convert one power of ten to another power of ten.
205 - Use the resistor color code.
206 - Identify component symbols used in electronic schematic diagrams.
207 - Identify schematic symbols for various types of electrical and electronic components.
208 - Identify semiconductors and their usage.
301 - Demonstrate the use of a multi-meter, function generator, and frequency counter to measure voltage, resistance and current.
302 - Make a circuit measurement to solve current requirements.
303 - Demonstrate the proper method of using an ohmmeter.
304 - Demonstrate the use of a power supply and adjust it to specified values.
401 - Utilize Ohm's law to determine current, voltage, or resistance.
402 - Demonstrate an understanding of the meaning of and relationship between voltage, current, resistance, and power in DC using Ohm's Law Pie Chart.
403 - Demonstrate the linear relationship between current and voltage.
404 - Describes the relationship between voltage, current and power in an electric circuit using Watt's Law.
405 - Calculate nominal resistor using the resistor color code.
501 - Demonstrate how voltages are distributed around a series circuit.
502 - Utilize double subscript notation.
503 - Demonstrate Kirchhoff's Voltage

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Retrieved Text: Voltage is the same across each branch in a parallel circuit.
The total current is equal to the sum of the individual branch currents.
The equivalent resistance (REQ) is less than the smallest branch resistance. The term equivalent resistance refers to a single resistance that would draw the same amount of current as all of the parallel connected branches.
Total power is equal to the sum of the power dissipated by each branch resistance.
A parallel circuit is formed when two or more components are connected across the same two points.
A common application of parallel circuits is the typical house wiring of many receptacles to the 120-V 60 Hz ac power line.
Fig. 5-1: Example of a parallel circuit with two resistors. (a) Wiring diagram.
The current in a parallel circuit equals the voltage applied across the circuit divided by the resistance between the two points where the voltage is applied.
Each path for current in a parallel circuit is called a branch. Each branch current equals V/R where V is the same across all branches.
Fig. 5-3: Parallel circuit. (a) the current in each parallel branch equals the applied voltage VA divided by each branch resistance R.
Components connected in parallel are usually wired across one another, with the entire parallel combination connected to the voltage source.
Fig. 5-5a: The current in the mainline equals the sum of the branch currents. Note that from G to A at the top of this diagram is the negative side of the main line, and from B to F at the bottom is the positive side. (a) Wiring

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Input Text: Read the passage below and choose the right answer to the following question (choices are Zorb to Krakatoa or or from Beanbag to Krypton? ):

In general, the farther away from the Sun, the greater the distance from one planets orbit to the next.


NASA has sent an unmanned probe to survey a distant solar system with four planets. Planet Zorb is farthest from the sun of this solar system, Planet Krakatoa is second farthest, Planet Beanbag is third, and Krypton is the closest. The probe visits the planets in order, first Zorb, then Krakatoa, then Beanbag and finally Krypton. Did the probe have to fly farther in its trip from Zorb to Krakatoa or or from Beanbag to Krypton??

Target Text: Zorb to Krakatoa or

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Retrieved Text: NASA might be done with the Space Shuttle, but that doesn’t mean the national space agency has given up on exploring those orbs we call planets that lie yonder. No sir, they in fact have a mission to Jupiter down the road, sending a solar-powered, windmill-shaped spacecraft known as Juno – making it the most distant probe to date that receives its electrical sustenance from the glowing ball of fire that we call the sun.
Juno will sport a trio of tractor-trailer-size solar panels which hopefully, will help it sail towards the largest planet in our Solar System across 2 billion miles. Juno will be launched this coming Friday aboard an unmanned Atlas V rocket.
NASA hopes that Juno’s foray into Jupiter will help them learn more about what could possibly be the oldest planet around in our Solar System, and this will be the first of three high-profile astronomy missions being served up across a time span of four months. Juno will travel for five years before arriving at its intended destination, so hopefully the mathematical calculations involved to help Juno get there are correct, and that no wayward asteroids will smash into Juno halfway there.
Filed in Gadgets >Green. Read more about NASA, Solar, Solar Power and Solar Powered.

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Retrieved Text: For the second time in history, a human-made object has reached the space between the stars. NASA’s Voyager 2 probe now has exited the heliosphere – the protective bubble of particles and magnetic fields created by the Sun. According to NASA, Voyager 2 now is slightly more than 11 billion miles (18 billion kilometers) from Earth. Mission operators still can communicate with Voyager 2 as it enters this new phase of its journey, but information – moving at the speed of light – takes about 16.5 hours to travel from the spacecraft to Earth. By comparison, light traveling from the Sun takes about eight minutes to reach Earth.
Voyager 2 is a space probe launched by NASA on August 20, 1977, to study the outer planets. Part of the Voyager program was launched 16 days before its twin, Voyager 1, on a trajectory that took longer to reach Jupiter and Saturn but enabled further encounters with Uranus and Neptune. However, as the mission continued, additional flybys of the two outermost giant planets, Uranus and Neptune, proved possible. As the spacecraft flew across the solar system, remote-control reprogramming was used to endow the Voyagers with greater capabilities than they possessed when they left Earth. Their two-planet mission became a four-planet mission. Their five-year lifespans have stretched to 41 years, making Voyager 2 NASA’s longest running mission.
We wrote about Voyager 1 when NASA received response from the spacecraft 13 billion miles away after 37 years of inactivity. Voyager 1 is NASA’s farthest and fastest spacecraft. It was launched on

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Retrieved Text: Over 1,000 unmanned missions have been sent into space to explore our solar system. NASA has launched both exploration and communication satellites into orbit. The missions have been both directly launched into space from earth and launched from a space shuttle once it was already in space. The first unmanned mission was Explorer 1. This project was launched in January 1958, two month's after Sputnik. This was early on in the space race. A more recent unmanned mission was the Hubble Telescope, which was launched in 1990. The closest planets to earth, Mars, Venus, and Mercury, have been the goals of more than four programs. The first was the Mariner in the sixties and seventies which visited all three of the planets. The Mariner was also the first to make a planetary flyby and a gravity assist maneuver. A gravity assist maneuver is where a satellite uses the gravity and velocity of a planet to reach its destination while simultaneously getting the opportunity for close up pictures of a planet. The Viking 1, was the first successful landing on Mars, and landed in 1976.
Twenty years later, NASA also launched rovers to mars on the Mars Pathfinder. This was also a very successful mission and got a lot of useful data from Mars. The Pioneer 10 visited Jupiter in 1973. Pioneer 10 was also the first spacecraft to leave the solar system in 1983. However, Voyager 2 had passed it in distance from our solar system. Both the Pioneer and Voyager program carried messages to earth. A

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Retrieved Text: What does a reddish snowman at the end of the Solar System have to do with new insights on the birth of planets?
On New Year’s Eve, the New Horizons spacecraft sent back to Earth the first images of the farthest celestial body yet encountered in the history of space exploration. It is called Ultima Thule.
Its shape is special and unusual. It resembles a red snowman.
»The New Horizon spacecraft is like a time machine. It took us to the time when the Solar System was being formed. We can observe the birth of planets, frozen in time,« said scientist Jeff Moore.
The shape of the celestial body is not only interesting because it is unusual, but also because it will reveal to scientists how the planets were created four and a half billion years ago.
»And it’s not just those in our Solar System, but also those that circulate around other stars in the galaxy,« added the NASA scientist.
Ultima Thule is more than six billion kilometres from Earth. It is located in the Kuiper belt, which extends far beyond the orbit of Neptune, the farthest planet of our Solar System.
The Astrophysicist Dr. Brian May, also known as a member of the group Queen group, wrote a special song to mark the twelve-year journey of New Horizon.
Why are we so excited about the birth of planets?
Do you know where does the nema Ultima Thule come from??
Was the space craft deliberately sent towards Ultima Thule??
The original version of this article was published on January 3rd.

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Retrieved Text: Make a good case for NASA to fund your exploration of one of our planets.
Each team will research at least one planet and create a presentation in order to make a recommendation to NASA that their planet be explored by the next space probe. NASA will provide funding to the group that makes the most compelling argument for their planet based on survivability factors or based on the best plan for building a habitable community on the planet.
Use the following resources to create your project.
Astronomy for Kids: A great site to get a quick overview of a variety Astronomy related subjects.
Exploring the Planets: This site is from the Smithsonian Air and Space Museum. Each planet and feature has it's own page of information AND pictures! Take a look and explore.
National Geographic Solar System: A great site with an overview of our solar system, plus lots of beautiful pictures and illustrations.
Nineplanets.org for Kids and Nineplanets.org: Two great sites in one place. The Kids interface is wonderful for a quick overview and some fun facts and pictures. Step up to Nineplanets.org to find more indepth information.
The Planets and Dwarf Planets: From NASA so you know it's good! It also has a link to see the "Level 2" version of the page if you want to challenge yourself with more complex information.
Solar System Exploration: The Planets: Another beautiful and informative NASA site. Fun to navigate and flush with great information.
Solar System Scope: A cool, interactive model of the solar system. You can zoom in on planets, view interplanetary distances,

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Retrieved Text: Are you looking for an exotic destination to visit this summer? Why not take a virtual trip to an Earth-size planet beyond our solar system with NASA's interactive Exoplanet Travel Bureau?
We live in a universe teeming with exoplanets, or planets outside our solar system. Unfortunately, even the nearest exoplanets are light-years away, so sending spacecraft and humans to these intriguing worlds remains a distant dream.
But on NASA's Exoplanet Exploration website, you can explore an imagined surface of an alien world via 360-degree, interactive visualizations. As you investigate each planet's surface, you'll discover fascinating features, like the blood-red sky of TRAPPIST-1d, or stand on a hypothetical moon of the massive planet Kepler-16b, which appears larger than either of the planet's two suns. The view from each planet's surface is an artist's impression based on the limited data that is available; no real photos of these planets exist.
The newest planet to feature this 360-degree surface visualization is Kepler-186f, an Earth-size planet orbiting a star much cooler and redder than the Sun. Scientists don't know if Kepler-186f has an atmosphere, but with the NASA visualization tool, you can see how the presence or absence of an atmosphere would change the view of the sky from the planet's surface.
Many of the exoplanets featured on the Exoplanet Exploration website were discovered by NASA's Kepler space telescope.
"Because Kepler-186f and the majority of Kepler-discovered planets are so distant, it is currently impossible to detect their atmospheres—if they exist at all—or characterize their atmospheric properties," said Martin Still, program scientist for NASA's newest space-based

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Retrieved Text: Nasa scientists are expected to make history today when they attempt the most distant fly-by of a celestial body yet.
Shortly after 9.30am UAE time, the New Horizons probe will zip past a mysterious 30 kilometre-wide object nicknamed Ultima Thule, which lies about 6.5 billion kilometres from Earth. That’s more than 2 billion kilometres beyond the outermost planet, Neptune.
To put the encounter into perspective, if our planet were shrunk to the size of an orange, the fly-by would be happening more than 50km away.
Yet such is the skill of its controllers, the probe is expected to zoom safely by the object at about 50,000kph, take crystal-clear pictures and then beam them back to Earth.
Even travelling at the speed of light, it will take six hours for the images to cross the void between the probe and its home planet.
This is no mere New Year Day’s stunt, however. Those images will be pored over by astronomers trying to solve one of the greatest mysteries in science: how our solar system was formed.
Ultima Thule – Latin for a place beyond the known world – is a Kuiper Belt object, belonging to a vast band of primordial debris that has been silently orbiting the Sun for billions of years far beyond the known planets. Despite being under the influence of the Sun’s gravitational field, the object is expected to have remained unsullied by the events that took place about 4.6 billion years ago, when the major planets began to take shape.
As such, Ultima Thule is probably the most pristine relic

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Retrieved Text: While millions of people are preparing for the New Year's Eve party, an unmanned spacecraft more than 110 million kilometers from Earth will fire its rockets to make history.
The NASA Osiris-Rex probe will descend into the asteroid Bennu and begin to orbit it just one and a half kilometers from the surface.
Never before had such a maneuver been attempted, which depends on the microgravity force exerted by the rock, barely 500 meters in diameter.
The insertion in orbit will be one of the first milestones for this mission, whose final objective is to touch the asteroid floor for five seconds, and to aspirate a sample of earth to send it back to Earth in the year 2023.
Bennu belongs to the oldest type of asteroids in the Solar System . It is thought that it has remained almost intact since it was formed 4 billion years ago .
These bodies contain organic compounds and amino acids, basic elements for life on our planet. But when one of these bodies impacts the Earth, much of its content burns in the atmosphere.
"This will be the first time we can analyze a pristine material that we have never had access to," says Javier Licandro , one of the four researchers from the Institute of Astrophysics of the Canary Islands who collaborate with the mission of the US space agency.
His team analyzes the images taken by the three cameras on board the probe and determines the composition of the asteroid, a task that will help to fix the extraction point of the sample.
On

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Retrieved Text: The probe "New Horizons" has sent new images of the most distant object of the solar system that humans have ever seen. "Ultima Thule," as the celestial body is called by Nasa, has a startling shape.
The NASA space probe "New Horizons" has a prominent fan. Queen guitar legend Brian May recently released a song called "New Horizons (Ultima Thule Mix)". Good: The musician is incidentally studied and doctorate astrophysicist. This explains May's personal enthusiasm for the US probe, which has gone as far into the cosmos as a few Earth devices. But now also laymen are interested in the probe: With "Ultima Thule", "New Horizons" has recently photographed the body of the solar system that has been farthest away from us.
That was at the turn of the year. Therefore, the message outside the Astroszene may have gone down a bit. Now new pictures show: The Brocken - officially it is called 2014 MU69 - has a quite surprising form. That it consists of two different sized parts, which are bound together by the effect of gravity, was already clear since the flyby. At first, the photos looked as if the celestial body, with its total diameter of about 30 kilometers, had the shape of a flying snowman. But now it turns out that it does not consist of balls - but at least one of the structures is flat as a pancake. And the other one is deformed too.
Graphics on the suspected form of "Ultima Thule"
Ralf Jaumann from the Institute of Planetary Research of the German

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Retrieved Text: As we enter 2019 there is a lot of uncertainty, Brexit, Trump’s Whitehouse, China’s economy, crashing stock markets to name but a few. However 2019 is also the 50th Anniversary of the magnificent moon landings when mankind took its first tentative steps into the Universe with courage and conviction.
As we celebrate this great achievement an unmanned Nasa probe – ‘New Horizons’ will be approaching a tiny rocky world :- ‘Ultima Thule’ is only 30km wide & is 6.5 billion kilometres from Earth, situated in the Kuiper belt a band of frozen material that orbits the Sun. Ultima is a further billion miles beyond Pluto & is the farthest body in our Solar System to be surveyed.
The intention is to beam back to Earth images & data from the probe in the early hours of the New Year.
Over the decades NASA has contributed a massive amount of invaluable knowledge for ‘the benefit of all mankind’ – long may it continue.
This entry was posted in social commentary and tagged Engineering, Innovation, leadership, NASA, project management, Space, U.S.A by admin. Bookmark the permalink.

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Retrieved Text: A flyby of Ultima Thule, a small, icy world located in the outer reaches of the Solar system, has been successfully completed by NASA’s New Horizons probe. Flying by the rock in the early hours of New Year’s Day, the probe sent a signal to the mission team on Earth to confirm its accomplishment. The signal, though, took some 14 hours to reach Earth.
The probe’s encounter with the Ultima Thule occurred about 6.5 billion kilometres from Earth, making it the “the most distant flyby” of an object in the Solar System by a man-made probe.
According to NASA, the spacecraft gathered several gigabytes of images and other data during the pass, but it will take several months to download the data completely.
“New Horizons holds a dear place in our hearts as an intrepid and persistent little explorer, as well as a great photographer. This flyby marks a first for all of us — APL, NASA, the nation and the world — and it is a great credit to the bold team of scientists and engineers who brought us to this point,” said Johns Hopkins Applied Physics laboratory director Ralph Semmel.
Ultima Thule is located in the Kuiper belt – the region of primordial objects comprised of dwarf planets, icy rocks and debris left over from the formation of the solar system about 4.6 billion years ago. This region lies more than two billion kilometres beyond Neptune and about 1.5 billion kilometres from Pluto.
New Horizons’ observations indicate that Ultima Thule is about 32 kilometres long and 16 kilometres wide.

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Retrieved Text: Unmanned instrumented probes obtain scientific information about the moon, other planets, and the space environment. Probes are differentiated from sounding rockets in that they attain at least 6400-kilometer altitudes. When a probe is launched on an escape trajectory-attaining sufficient velocity to travel beyond the earth's gravitational field-it becomes, in effect, a satellite of the sun. The Lunar Orbiter probes, however, were sent into orbit around the earth's natural satellite, the moon.
In May 1960-at the suggestion of Edgar M. Cortright, Assistant Director of Lunar and Planetary Programs-NASA adopted a system of naming its space probes. Names of lunar probes were patterned after land exploration activities (the name "Pioneer," designating the early series of lunar and related space probes, was already in use). The names of planetary mission probes were patterned after nautical terms, to convey "the impression of travel to great distances and remote lands." Isolated missions to investigate the space environment were "assigned the name of the mission group of which they are most nearly a part."3 This 1960 decision was the basis for naming Mariner, Ranger, Surveyor, and Viking probes.
U.S.-German Helios 1 solar probe on the spin table for system test and checkout before mating to the Titan III launch vehicle.
The project was designated "Helios," the name of the ancient Greek god of the sun, by German Minister Karl Kaesmeier. The name had been suggested in a telephone conversation between Minister Kaesmeier and Goddard Space Flight Center's Project Manager, Gilbert W. Ousley, in August 1968.2 NASA had previously used the name for the Advanced Orbiting

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Retrieved Text: Saturn is the farthest planet from Earth that can still be seen with the naked eye.
Saturn’s spectacular rings give the planet a distinctive appearance that captures the imagination in a way that few other celestial objects can. Named for the Roman god of agriculture, this sixth planet from the sun consists of swirling clouds of hydrogen and helium, giving Saturn a striped or banded appearance. More than four centuries of research have revealed many of Saturn’s secrets, though the Cassini spacecraft continues to provide even greater access to this faraway planet.
Italian astronomer Galileo Galilei was the first person to make observations of Saturn through a telescope in 1610. At first, he thought the planet was surrounded on both sides by two sphere-shaped objects. Later he identified these objects as handles attached to the planet. By 1659, astronomers realized that Galilei’s handles were actually rings surrounding Saturn. Telescopes and other tools provided small glimpses into Saturn until 1979, when Pioneer 11 became the first spacecraft to reach the planet. In 1997, NASA launched Cassini, a craft that reached Saturn in 2004 and sent a probe to land on Saturn’s moon Titan in 2005. The Cassini mission was extended several times and should continue to provide new information through at least 2017.
Unlike the four planets closest to the sun, which are known as terrestrial planets due to their rocky surfaces, Saturn, Jupiter, Uranus and Neptune feature a gaseous structure. Saturn consists of hydrogen and helium mixed with small amounts of ammonia and methane gas, with a surface temperature

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Retrieved Text: The known universe just got a lot bigger as the Kepler spacecraft has discovered over a thousand new planets orbiting distant stars. In July 2015, the space telescope identified 4,302 potential exoplanets — and further analysis has revealed that 1,284 of those candidates have a 99% likelihood of being a planet. A further 1,327 identified objects are also likely to be planets, but require further study before they can be classified. The study also validated 984 additional planets that had been identified using other techniques. This is the largest number of exoplanets ever identified at one time.
Kepler identifies potential planets by looking for changes in the brightness of other suns that occur when objects pass in front of the star. For four years, the telescope monitored 150,000 stars in a single patch of sky, looking for these slight flickers of light. In the past, individual planet candidates had to be painstakingly verified one by one. This is the first time NASA has used a statistical analysis method to validate multiple planet candidates simultaneously, vastly accelerating the process.
Out of the thousands of now-known exoplanets, only a handful — 550, to be precise — are likely to be rocky planets like Earth based on their size. Out of those, only nine orbit their suns in the habitable zone that would allow liquid water to pool and potentially nourish life. This discovery brings the number of planets capable of possibly harboring life as we know it to just 21 total.
In coming years, it’s likely the number of identified exoplanets

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Retrieved Text: The closest rocky planet outside our solar system, which is larger than Earth and the potential gold mine of science data. Even though it is too much hot to visit, and it significantly closer than Kepler but it’s 21 light years away from Earth. The new horizons probe of Nasa has famed for taking recent stunning pictures of Pluto.
If you were on a spaceship and going fast, it’d take you just over 387,000 years to get to HD 219134b from planet Earth. Michael Werner, who is the project scientist for the Spitzer mission at Nasa. He said that, “this exoplanet will be one of the most studied for decades to come.” This exoplanet has been tipped as a perfect observation subject by James Webb Space Telescope of Nasa, which will be launched in 2018. Complex observations into this exoplanet have unveiled that, it is around 4.5 times heavier than planet Earth.
By observing the planet when it passes in front of its star, scientists can observe minor changes in the light, caused by the differing reflections of different chemicals in its atmosphere. Planets like this one belong to a growing list of planets called ‘super Earths’ planets that are similar in makeup but slightly larger than our own planet, a category that includes Kepler 452b. It is also around 1.6 times larger than Earth, and by combining the estimated size and mass, scientists have figured out its density, concluding that the planet is rocky, like our planet and not icy, or gaseous. Even though the planet is

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Retrieved Text: A new drawf planet R245????
COULD FIND NEW PLANETS IN THE SOLAR SYSTEM?
Artist's concept of the hypothetical "Planet Nine".
Artist’s impression of the Large Synoptic Survey Telescope (LSST).
of six of the most distant KBOs, and the possible “Planet 9” (aka. “Planet X”).
The orbits of several KBOs provide indications about the possible existence of Planet 9.
The presently known largest small bodies in the Kuiper Belt are likely not to be surpassed by any future discoveries.
Brown and his team have concluded that those days are over.
What is a Drawf Planet?
At least two unknown planets could exist in our solar system beyond Pluto. / Credit: NASA/JPL-Caltech.
Could there be another Pluto-like object out in the far reaches of the Solar System? How about two or more?
called extreme trans-Neptunian objects (ETNO).
Evidence of an ancient collision, perhaps?
Three kerbals touch down on the surface of the small moon Hi'iaka in the depths of the Kuiper Belt.
(see video icon to appreciate this, as KSP cannot render it for larger objects).
After a relatively painless docking high above Hi'iaka's plains, the kerbals prepare to embark on the next leg of their journey: Orcus and Vanth.
Suggest future objects for visiting in the comments. Avoid tiny objects please, and dwarf planets with moons are a big plus.
My rendition of the dark red spot on the surface of Kuiper belt object Haumea.
Artist concept of Haumea, with the correct proportions of the main body and the ring.
and is darker than the surface of the dwarf planet itself.
Credit: Instituto de Astrofísica de Andalucía.
Artist’s impression of the moderately red Quaoar and its moon Weywort.
Artistic

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Retrieved Text: National Aeronautics & Space Administration (NASA), which is an independent agency of the of the United States federal government’s executive branch, has planned to launch Parker Solar Probe in the summer of 2018, aimed to explore the atmosphere of the sun. This probe launch is entirely focused to study outer atmosphere of the Sun and to have an in-depth understanding of how the sun works.
Initially, the name of the probe was Solar Probe Plus, which was renamed to the Parker Solar Probe, honouring astrophysicist Eugene Parker. For the very first time, NASA has named a spacecraft after a living person.
Eugene Parker is an American astrophysicist who in the mid-1950s described the theory on the supersonic solar wind and also predicted solar magnetic field’s Parker spiral shape in the outer solar system. A research paper was published by Eugene Parker that predicted solar wind’s existence in 1958. Before Parker theory revealed that solar wind is the flow of gases from the Sun, it was believed that vacuum is between the planets.
The Parker Solar Probe is 10-feet high and will fly within Sun’s surface’s 6.4 million km into the solar atmosphere.
The objective of the Parker Solar Probe launch is to study the atmosphere of the Sun in detail, put some light on Planet Earth and its place in the solar system.
The probe will be the first human-made probe to face the brutal heat of the sun and the radiation.
The probe mission is aimed at determining the dynamics and structure of the plasma and magnetic fields at solar wind

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Retrieved Text: So if anyone has been reading he news lately they are likely aware that Pluto, our farthest and smallest “Planet”, has been demoted out of the solar system. No no it has not been voted off as the weakest link but rather changed. During the annual International Astronomical Union conference this year the astronomical community voted to change the definition of what a planet is. This is due to two recent discoveries of planets that have an orbit around the sun, and whose masses are larger than Pluto.
The debate has waged since 2003 on whether we should include the celestial body known as Xena as the 10th planet or should we demote Pluto. It is also important to keep in mind that Pluto is smaller than our moon, so it is a very small object on the scale of out solar system. So at the conference they voted to demote the planet to a “Dwarf Planet” and include two new bodies “Xena and Ceres” as Dwarf Planets. This only makes sense, as you cannot ignore to objects that fit the traditional definition of a planet, and are larger than our smallest family member is.
is not a satellite of a planet, or other nonstellar body.
But already opposition has started in the media. The CBC has run an article where NASA officials refer to this decision as bad science and sloppy. Of course, they consider their selves as the top officials in space, even though a manned moon mission has not been attempted since 1972 and in the

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Retrieved Text: Meet The New Dwarf Planet That Was Discovered In Our Solar System!
There's still so much we don't know about our solar system, and as it slowly reveals more of its secrets we can't help but be star dazed. The newest information is on the discovery of a very distant dwarf planet that can help us understand how planets are formed. Meet DeeDee!
Distant Dwarf, or DeeDee for short, is located really far from our planet.
At a far corner of the solar system, DeeDee is a very important discovery for science. We received the first signals related to it in 2016 but we knew too little about its physical structure.
The Atacama Large Millimeter/submillimeter Array (ALMA) radio telescopes recently made new observations that excited scientists.
Because apparently DeeDee is a much larger object than what was previously thought and it's very surprising that it wasn't observed up to this day. Unfortunately, DeeDee doesn't fully meet the scientists' requirements to become the 9th planet of the Solar System.
DeeDee is 2/3 the size of Ceres, the largest dwarf planet in the solar system.
Just like Ceres, the largest member of the asteroid belt, DeeDee has a big enough mass to make it globe shaped. That's why it's considered to be a dwarf planet rather than an asteroid. But we still need to wait for its official categorization and naming.
DeeDee's distance to the Sun is about 85 billion miles (137 billion kilometers).
It takes 13 hours for the sun rays to reach DeeDee. That makes it the dwarf planet farthest from the Sun, after Eris.

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Retrieved Text: Jack Jonathan Lissauer is a space scientist in the Space Science and Astrobiology Division, NASA Ames Research Center, Moffett Field, Calif. He is a science co-investigator on the Kepler space telescope mission. NASA's Kepler spacecraft will search for Earth-size planets orbiting distant stars following its scheduled 2009 launch. ( http://www.nasa.gov/centers/ames/research/2007/kepler_feature.html) Lissauer is a Consulting Professor at Stanford, teaching advanced-level classes in planetary sciences and astrobiology.
He and his colleagues -- including Geoffrey W. Marcy, professor of astronomy, University of California, Berkeley (http://astro.berkeley.edu/~gmarcy/) -- have discovered four extra-solar planets – planets beyond our solar system. Lissauer and Mark Showalter of the SETI Institute, Mountain View, Calif., in 2003 discovered two moons of Uranus – Mab and Cupid -- as well as two additional rings around the planet – named with the Greek letters Mu and Nu.
Left: Jack Lissauer portrait. Click on the photo for high-resolution image.
Lissauer's research interests include planetary astrophysics; planet and star formation; detection of extra-solar planets; assessing the abundance of habitable planets; rotation of planets and comets; craters on planets and moons; circumstellar disks (disks that revolve around stars); resonances and chaos (gravitational interactions among planets that can change their orbits); and planetary rings and moons.
Lissauer holds a doctorate in applied mathematics granted by the University of California, Berkeley, in 1982. His thesis is entitled "Dynamics of Saturn's Rings." He also has a degree in mathematics from the Massachusetts Institute of Technology, Cambridge, Mass.
Prior to joining NASA, Lissauer was an associate professor (September 1993 - August 1996) and assistant professor (June 1987 - August 1993)

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Retrieved Text: NASA’s Juno spacecraft has broken the interplanetary distance record for solar-powered spacecraft. The Jupiter explorer is close to half a billion miles from the Sun, setting a new standard for using solar power for deep space exploration.
Juno crossed the record-breaking 493 million miles from the Sun at 19pm GMT on Wednesday January 13, 2016. This is the farthest any solar-powered explorer has ventured into deep space, which is usually occupied soley by robots running on radioisotope thermoelectric generators (RTGs). The previous record-holder is the European Space Agency’s still-functioning Rosetta spacecraft when it first intercepted comet 67P/Churyumov-Gerasimenko in October 2012. Before that, no solar powered craft had even made it past the asteroid belts.
Now Juno is going to keep pushing the record further, out to Jupiter. Once it reaches the gas giant, the explorer will be serving as a proof of concept for a new, more efficient solar power system. At up to 517 million miles from the Sun, the spacecraft is basking in only a quarter of the sunlight we receive on Earth. But what the panels get, they use well: Juno has a 28 per cent conversion rate turning sunlight into power.
Juno’s solar power arrays so big, they were nearly too heavy to launch in 2011. The four-ton spaceraft has three 10-metre-long solar arrays with 18,698 individual solar cells. While they’ll only generate 500 watts of power out by Jupiter, they’re big enough that they’d generate 14 kilowatts here on Earth.
Yet they’re just barely enough to keep the spacecraft fully operational at distant Jupiter. If

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Retrieved Text: « The days are numbered for the dark matter?
The first to pick up the signals from the probe New Horizons will not be NASA technicians, but experts working at the Canberra Deep Space Communication Complex (CDSCC) CSIRO, which then will send the images directly to the Jet Propulsion Laboratory (JPL). And the company has started the initiative Pluto Time.
We, missing very little arrival of NASA’s New Horizons in the orbit of Pluto . At 13:49 (Italian time) we could say officially that he had explored the entire solar system (at least all the planets), a company that began more than 50 years ago and that certainly will not end with this mission. But the first to pick up the data from the probe (launched January 19, 2006 from Cape Canaveral) will not be NASA technicians, but experts working at the Canberra Deep Space Communication Complex (CDSCC) CSIRO , which then will send the ‘picture directly at the Jet Propulsion Laboratory (JPL).
After 3462 days of the mission, the world will finally know how it’s done Pluto, how big, how to make up its atmosphere and how it interacts with the solar wind. All from 12,500 km from the surface of the dwarf planet (Pluto no longer a planet since 2006). The NASA probe will study in detail even the system of five icy moons orbiting Pluto 134340 (his real name), the first to be studied is Charon, which is also the largest (forms a binary system with the planet nano), slightly smaller than Pluto; follow Hydra and

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Retrieved Text: Planet X is the name given to any hypothetical planet yet to be discovered in our Solar System. Percival Lowell originally coined the term back in the early 1900’s. Lowell is the same astronomer who thought he saw canals on the surface of Mars, “proving” the existence of a Martian civilization.
At one time, Uranus and Neptune could have born the Planet X title. Scientists long suspected the existence of a seventh planet due to anomalies in the orbit of Saturn. After Uranus was discovered, anomalies in its orbit hinted at the existence of Neptune, and anomalies in Neptune’s orbit hinted that there might be even more planets beyond it.
Recent data from the Wide-Field Infrared Survey Explorer, a.k.a. WISE, found no evidence of a Planet X, which seemed to put the matter to rest once and for all. There are lots of dwarf planets out there, like Pluto and Eris, but nothing large enough affect Neptune’s orbit in any meaningful way.
Now NASA scientists are proposing the existence of Planet X again to explain anomalous perturbations in the orbits of two of the most distant known dwarf planets. To be fair, WISE failed to detect any Saturn or Jupiter-sized planets. This new Planet X would be much smaller, closer to the size of Earth or Mars.
It seems our Solar System just keeps getting more and more crowded.
Posted by J.S. Pailly on March 28, 2014 in Sciency Words and tagged Percival Lowell, Planet X, WISE Telescope.
I love Science Fiction, can’t wait for more astrological discoveries!

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Retrieved Text: Comment With everyone going ape over the dazzling new crisp pictures from NASA's New Horizons probe of the dwarf freezeworld Pluto, there are few voices asking if it was worth sending out a space probe to the far end of the Solar System – but it wasn't always that way.
When a journey to Pluto was first mooted in the late 1980s, there was a lot of criticism of the idea, both within NASA and definitely within US Congress. After all, it's a small rock in the middle of nowhere – what's the point?
Even as New Horizons got closer, there were naysayers bemoaning the cost of such a mission ($700m, since you asked). Never matter that the entire program costs less than three F-35 fighters – some seem to think that we aren't getting enough bang for our buck and aren't there bigger fish to fry.
While it's fascinating that we're seeing close-up images of another planetary body for the first time, there's a hard science element to the mission that can sometimes be ignored. The fact is, New Horizons has already delivered enough useful new science to justify the time and money spent on the program, and will carry on paying its way for years to come.
Even before the probe had left the laboratory, the scientific payback was starting to come in. New components had to be developed and new materials were needed to get the probe small enough for an easy launch and tough enough to survive the journey. The whole thing had to be engineered

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Retrieved Text: Uranus is the first of the ice giant planets. Its atmosphere, like Saturn and Jupiter’s, is filled with hydrogen and helium, but Uranus’ atmosphere also has high amounts of methane that gives the planet its blue tint as the light reflects off its cold tops.
Like Venus, Uranus rotates east to west, and a single rotation takes a little over 17 Earth hours. The planet has unique axis tilt that causes the planet to appear as if it is rotating on its side. Uranus takes 84 Earth years to complete a single orbit around the Sun. Two sets of rings encircle the planet, with the inner set being narrow and dark and the outer ring, unseen until 2003, is brightly colored.
Uranus has not been an object of significant study by scientists. Most of what is known about Uranus was gathered by the Voyager 2 spacecraft in 1986, the only spacecraft to visit the planet. Other research of the planet has largely been performed with images gathered by the Hubble Telescope.
A new 4-minute film casts digital humans in real extraterrestrial destinations, guided by the timeless words of Carl Sagan.
Scientists had believed that Uranus' orbit was too unstable to play host to an asteroid companion.
These are the first images of the event since NASA Voyager probe snapped images in 1986.
October 11, 2011, 2:34 p.m. by Space.com Inc.
The planet's unique tilt indicates that major impacts were typical for the formation of planets.
February 18, 2011, 6:51 p.m. by Space.com Inc.
A NASA spacecraft heading for Mercury beams back an amazing space photo:

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Retrieved Text: NASA's Kepler space observatory has found more than 1,200 potential alien worlds since it began hunting for extrasolar planets in 2009.
Observations from the mission's first four months alone have unlocked a flood of exoplanet possibilities, including 54 candidates for habitable worlds orbiting distant stars. Today (Feb. 2) NASA unveiled the latest set of observations from that four-month period.
NASA officials expect the $600 million Kepler observatory to continue staring at its target patch of sky until at least November 2012.
$600 million: The cost of the Kepler planet-hunting mission at its launch in March 2009.
156,000: The number of stars in the constellations Lyra and Cygnus that the Kepler observatory is staring at 24 hours a day, seven days a week, in the search for extrasolar planets. Kepler's field of views covers about 1/400th of the sky.
1,235: The number of potential alien planets that Kepler has discovered. NASA has repeatedly cautioned that all of Kepler's findings must be confirmed by follow-up observations using other space and ground telescopes.
662: The number of planet candidates found by Kepler that would be about the size of Neptune. Neptune has a radius of about 15,388 miles (24,764 km) wide and has a mass that is 17 times that of the Earth, according to NASA.
288: The number of exoplanet candidates discovered by Kepler that are in the super-Earth class. Super-Earths are planets with masses between two and 10 times the mass of Earth, according to NASA.
170: The number of stars that seem to have more than one planetary candidate orbiting them – which would

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Retrieved Text: LOGAN, UTAH -- The Utah State University Research Foundation announced today that it has selected Major General Susan K. Mashiko, USAF(RET) to serve as a member of its Board of Trustees.
LOGAN, UTAH -- When it comes to space exploration, the Space Dynamics Lab at Utah State University plays a big role.
LOGAN, UTAH, August 24, 2016 – The Utah State University Research Foundation and its Space Dynamics Laboratory announced that it has received an indefinite delivery, indefinite quantity contract valued at up to $99.4 million over the next five years from the Department of Defense.
NORTH LOGAN — Kids of Utah State University Space Dynamics Lab employees celebrated the start of construction for a new building with a “skybreaking” by launching model rockets Thursday afternoon.
Does the Solar System Really Have a Ninth Planet?
Caltech researchers Konstantin Batygin and Mike Brown, who initially made the announcement about the possible existence of Planet Nine, have published new findings that have helped narrow down the current location of the mysterious giant looming over Earth in the far outer Solar System.
Thirty-four graduating seniors were honored Friday by the Utah State University Research Foundation and Space Dynamics Laboratory for their work at the two institutions while in college in Logan.
In 2011, astronomers announced that our galaxy is likely teeming with free-floating planets. In fact, these lonely worlds, which sit quietly in the darkness of space without any companion planets or even a host sun, might outnumber stars in our Milky Way Galaxy.
In 2011, astronomers reported our galaxy is likely filled with roaming planets not

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Retrieved Text: Tuesday, July 14, 2015 • After almost a decade, NASA’s New Horizons spacecraft made its closest pass to Pluto. The deep space probe will survey the surface of the icy dwarf-planet and send back photos never before seen. Intersection’s Brendan Byrne talks with the mission’s principal investigator Doctor Alan Stern about the mission.
Monday, July 13, 2015 • NASA’s New Horizons spacecraft is making its closest approach to Pluto Tuesday morning. The deep space probe will survey the surface of the icy dwarf-planet and send back photos never before seen.
Monday, July 13, 2015 • International Space Station astronauts will unpack much needed supplies Monday. Two previous attempts to resupply the station failed – including a SpaceX mission that exploded shortly after liftoff late last month.
Monday, July 6, 2015 • After nearly a decade of traveling through space, NASA’s New Horizons probe is about to arrive at Pluto. On Tuesday it will begin an intensive, weeklong study of the distant world.
Monday, June 29, 2015 • Space X is reviewing every frame of video to find out exactly why its Falcon 9 rocket exploded shortly after liftoff Sunday. Search crews are also on the hunt for fallen debris.
Sunday, June 28, 2015 • A SpaceX Falcon 9 rocket carrying supplies to the International Space Station exploded shortly after takeoff.
UCF Researcher: How Are Planets Formed?
Tuesday, March 3, 2015 • Scientists are missing a key part of information in uncovering how planets are formed in our universe. One University of Central Florida researcher received a grant from NASA to conduct an experiment

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Retrieved Text: NASA has added a feature to its Exoplanet Exploration website that helps you explore exoplanets.
It’s called the Exoplanet Travel Bureau, and as the name suggests, it aims to give you an idea of what it would be like to travel to a planet outside our solar system.
Since 1992, 3,730 exoplanets have been confirmed as found, with another 4,496 candidates across 2,783 star systems.
The vast majority of them, sadly, aren’t fit for human habitat. They’re mostly too hot, too oxygen-starved, too radioactive or any number of other extreme variables that just aren’t conducive to visitors actually staying alive.
That’s what NASA’s researchers think Kepler 186f might look like. Pretty boring unless you add atmosphere.
“Because Kepler-186f and the majority of Kepler-discovered planets are so distant, it is currently impossible to detect their atmospheres – if they exist at all – or characterize their atmospheric properties,” Martin Still, program scientist for NASA’s newest space-based planet-hunting observatory, the Transiting Exoplanet Survey Satellite (TESS), explains.
If you haven’t visited NASA’s alien worlds website, you’ll find it’s a great rabbit hole. It’s easy to use, and perfectly edited to be engaging for just about any audience.
Among them include the planet being eaten by its own star, a world that is half daylit lava and half permanent darkness, and a blue world where 8600 km/h winds eternally blow shards of glass sideways.
Equally fun is the Universe of Monsters where NASA’s team has identified six planets which would be great homes for classic nightmare creatures, such as TRAPPIST 1b – the perfect planet for werewolves, with

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Retrieved Text: "Voyager 1 crossed this point nearly six years ago so this is now quite a different time in solar activity and now they are in different places - Voyager 1 was up and Voyager 2 is down and to the left in the southern hemisphere".
This was because the planned route for Voyager 2 was significantly longer, with it being set on a flyby course with numerous outer planets, revealing the first close-ups and important scientific data on planets such as Saturn, Neptune and Uranus. Sadly the spacecraft won't still be sending us data at that point. Estimates of how far the Oort Cloud stretches vary between about 1,000 astronomical units (AU) - one AU is the distance between the Sun and the Earth of about 150 million kilometers - and 100,000 AU.
"Working on Voyager makes me feel like an explorer, because everything we're seeing is new", said John Richardson, principal investigator for the PLS instrument and a principal research scientist at the Massachusetts Institute of Technology in Cambridge. "Now we're looking forward to what we'll be able to learn from having both probes outside the heliopause".
At the end of last year, NASA for the first time in 37 years, started back engines, "Voyager 1", which will allow you to maintain the connection with the device two to three years.
Of course, that's a rather long time - particularly when one considers that the Voyager probes are already massive overachievers when it comes to longevity.
Voyager 2, at 11 billion miles from Earth, has entered the stars.
With both Voyager

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Input Text: Read the passage below and choose the right answer to the following question (choices are alkane with fewer carbon atoms or alkane with more carbon atoms? ):

Alkanes with more carbon atoms have higher boiling and melting points, so some of them are solids at room temperature.


Kathy did some experiments on two different alkanes and one of the alkanes had twice as many carbon atoms than the other. She would notice that which alkane would require a higher temperature to melt alkane with fewer carbon atoms or alkane with more carbon atoms??

Target Text: alkane with more carbon atoms?

#### Retrieved Documents ####

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: Because they are saturated compounds, the organic, hydrocarbon compounds, alkanes, tend to show very little reactivity. However, there are a few reactions that alkanes can and do undergo under specific conditions. These reactions include combustion, substitution and cracking. The reactions of alkanes are very important in everyday life.
Combustion is the most important reaction of alkanes. Alkanes burn in oxygen to form carbon dioxide and water vapor. If there is insufficient oxygen for the reaction, carbon monoxide and sometimes even carbon is formed instead of carbon dioxide. In actuality, there is always a certain amount of carbon monoxide formed in the process.
This is the reaction that occurs in internal combustion engines. It is the production of these gases, carbon dioxide and water vapor, and even the carbon monoxide, that allows the useful work of engines.
Very large alkanes are not as useful to human as smaller, short-chained ones. As a result, large alkanes are often cracked to produce smaller, more useful alkanes. During this process, alkenes and hydrogen gas may also be formed. The cracking of alkanes is carried out at 450 degrees celcius over an aluminum oxide or silicon oxide catalyst.
Alkanes can be converted to halogenoalkanes via substitution. This reaction only occurs in light or at high temperatures. As the name suggests, a replacement is made. One or more hydrogen atoms on the alkane is replaced by one or more halogen atoms. This reaction occurs mainly with chlorine, bromine and iodine. The halogen, fluorine, however, does not form halogenoalkanes having reacted with alkanes. Instead, carbon and hydrogen

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Retrieved Text: Alkenes. Showing top 8 worksheets in the category - Alkenes. Some of the worksheets displayed are Naming and drawing alkenes work and key, Alkenes and alkynes work and key02 25 10, Work, Alkanes and alkenes work, Chapter 8, Work alkenes, Chem1002 work 3 addition reactions model 1 addition, Naming alkenes work cr 305 h3c ch3.
Alkenes and Alkynes Worksheet and Key 1. Draw the line bond structures for the following alkenes, cyclic alkenes, and alkynes: a) alkenes that contain 4 carbon atoms (three possible) b) cyclic alkenes that contain 4 carbon atoms (three possible) c) alkynes that contain 4 carbon atoms (two possible, neither of them are cyclic alkynes) 2.
Naming Alkanes Alkenes And Alkynes. Displaying all worksheets related to - Naming Alkanes Alkenes And Alkynes. Worksheets are Naming and drawing alkenes work and key, Naming alkanes, Naming alkynes work 1 c4 305, Work naming and drawing alkanes, Naming alkanes alkenes and alkynes quiz 70, Alkenes and alkynes work and key02 25 10, Work for organic chemistry, Naming alkanes work 1.
Organic Nomenclature - Alkanes, Alkenes, Alkynes Naming organic compounds can be a challenge to any chemist at any level. Historically, chemists developed names for new compounds without any systematic guidelines. In this century, the need for standardization was recognized.

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Retrieved Text: The numerous organic compounds can be grouped into a comparatively small number of series or families of compounds known as homologous series. The simplest series of compounds in organic chemistry is the alkanes. We shall study this series to illustrate what a homologous series means.
The alkanes are a series of hydrocarbons with a general molecular formula of CnH2n + 2, where n is a whole number with a value of one or more.
From the table below, we see that each individual member of the alkane series differs from the preceding or the following member by one carbon atom and two hydrogen atoms, i.e. –CH2– group. Such a family of compounds is known as a homologous series and each individual member is referred to as a homologue.
A homologous series is a family of organic compounds which follows a regular structural pattern, in which each successive member differs in its molecular formula by a –CH2 – group.
Other homologous series include the alkenes, CnH2n, the alkanols, CnH2n+1 OH, and the carboxylic acids, CnH2n+1 COOH. Homologous series have the following common characteristics.
General Molecular Formula: All members share a general molecular formula, i.e., CnH2n + 2 for the alkanes, CnH2n for the alkenes, and so on.
Difference Between Successive Homologues: Each successive member in such a series differs in its molecular formula by the addition of a –CH2– group and in its relative molecular mass by an increase of 14.
Physical Properties: The physical properties of the members change gradually as the number of carbon atoms per molecule increases. For example, the boiling

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Retrieved Text: Alkanes are hydrocarbons that only consist of single bonds. The ratio of carbon atoms to hydrogen atoms in alkanes is always in the form of n: 2n+2.
Alright. Let's talk about alkanes. And alkanes are hydrocarbons, compounds consisting of hydrogen and carbon, that only consist of single bonds, okay? Just single bonds in this carbon chain, this carbon back bone. So the formula for this is going to be CNH2N+2. Okay. So let's talk about several different types of alkanes you might see and come across.
So the first one, the simplest one is methane. Methane is CH4 consisting of one carbon and four hydrogen. And this is [IB] when you use methane, you [IB] this is like a natural gas, gas that might come from our body, something like that is methane. Okay? And notice the prefix meth, is dealing with one carbon, okay?
Next one is ethane. Ethane is dealing with two carbons. The prefix eth, is talking about two carbons and this is typically using c talking about different types of reactions [IB] and some things like that. This is ethane is typially used as a catalyst. Meaning that it helps the reaction move along. In fact three carbons we're going to take the three carbon chain it's going to have a prefix of prop. Meaning three carbons. And this is used, and you're talking about propane gas, propane tanks and things like that. You've probably heard of that when you go camping. You use that with fuel, those are you simplest fuel used for cooking

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: The increasingly large number of organic compounds identified with each passing day, together with the fact that many of these compounds are isomers of other compounds, requires that a systematic nomenclature system be developed. Just as each distinct compound has a unique molecular structure which can be designated by a structural formula, each compound must be given a characteristic and unique name.
Such common names often have their origin in the history of the science and the natural sources of specific compounds, but the relationship of these names to each other is arbitrary, and no rational or systematic principles underly their assignments.
A rational nomenclature system should do at least two things. First, it should indicate how the carbon atoms of a given compound are bonded together in a characteristic lattice of chains and rings. Second, it should identify and locate any functional groups present in the compound. Since hydrogen is such a common component of organic compounds, its amount and locations can be assumed from the tetravalency of carbon, and need not be specified in most cases.
 A root or base indicating a major chain or ring of carbon atoms found in the molecular structure.
 A suffix or other element(s) designating functional groups that may be present in the compound.
 Names of substituent groups, other than hydrogen, that complete the molecular structure.
As an introduction to the IUPAC nomenclature system, we shall first consider compounds that have no specific functional groups. Such compounds are composed only of carbon and hydrogen atoms bonded together by sigma bonds (all carbons

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Retrieved Text: Having spent millions and millions of dollars surveying, exploring, appraising, designing, and developing a site, what do we have to show for it? This depends very much on the type of reservoir. ‘Oil and gas’ isn’t just one category (or even two), but covers a very broad range of mixtures defined by their chemical components.
From a commercial point of view, everything in oil or gas can be considered a hydrocarbon, an inert substance, or a contaminant. In the vast majority of reserves, hydrocarbons make up the vast majority of the mass and volume. This is just as well since they are the part we are most interested in. Hydrocarbons are, as the name implies, compounds made entirely of carbon and hydrogen, which come in an astonishing variety of shapes and sizes because of carbon atoms’ tendency to bond together in chains and rings.
The more common type of hydrocarbons is the aliphatic group, consisting of ‘chains’ and most types of ‘rings’. The simplest is methane, which is a gas has just one carbon atom and four carbon atoms. As we add carbon atoms in a line we get ethane, butane, propane, and pentane, all of which are gasses at room temperature; six carbon atoms make up the backbone of hexane, which is a liquid. These form a class of compounds called alkanes, which continue as you add more carbon atoms, forming increasingly viscous liquids and eventually solids (polythene is technically a very large alkane). Variants on the alkanes are the cycloalkanes, which are simple loops; alkenes and

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Retrieved Text: Petroleum is made up of many different hydrocarbons, some of which are in far greater demand than others.
In order to obtain more of the hydrocarbons in greater demand (which are general small molecules), hydrocarbons in lesser demand are broken down through a process known as catalytic cracking.
Alkanes with 15 to 25 carbon atoms per molecule are broken into two smaller molecules, one an alkane and the other an alkene.
The alkene further splits into smaller alkenes until ethylene, propene, or a combination of both is formed.
Thus, ethylene is a major by-product of catalytic cracking.
Catalytic cracking is not sufficient to meet demands for ethylene, and therefore some fractions of petroleum are decomposed completely to produce ethylene through steam thermal cracking.

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Retrieved Text: There are 5 lectures in this section of science wherein you are going to learn about Carbon and its compound. This is a very important chapter of Science and accounts for about 23 marks with periodic classification of elements. In Carbon and its compound You will learn the following as per the syllabus: Covalent bonding in carbon compounds. Versatile nature of carbon. Homologous series, Nomenclature of carbon compounds containing functional groups (halogens, alcohol, ketones, aldehydes, alkanes and alkynes), difference between saturated hydrocarbons and unsaturated hydrocarbons. Chemical properties of carbon compounds (combustion, oxidation, addition and substitution reaction). Ethanol and Ethanoic acid (only properties and uses), soaps and detergents.
This is first lecture of the Carbon and its compound which is the fourth chapter and is very important for SA-2 as it covers about 15-18 marks in exams. In this session you will learn about the Carbon and its properties. As you know carbon is an element and it has 4 valence electrons in its outermost shell, its valence electron are responsible for the entire change in the behavior and thus it forms maximum number of compounds. You will study here the terms covalency, catenation, tetravalency. The you will learn about the occurrence of Carbon. Sharing of electrons by Carbon. Then you will study the properties of hydrogen and how it forms compounds with hydrogen.Occurrence of allotropes of Carbon i.e.,Diamond, Graphite and Buckministerfulerene. You will study the properties of all three isotopes and difference among the three. You will also discuss the term Allotrophy, organic, Inorganic compound, saturated and

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Retrieved Text: Formula and structure: The propane chemical formula is C3H8 and is extended formula is CH3CH2CH2. Its molar mass is 44.097 g mol-1. The molecule is formed by a chain of three carbon atoms which are bound to 3 or 2 hydrogen atoms in order to complete the 4 bonds required to complete the octet of Lewis structure. The carbon atoms are sp3 hybridized, thus the molecule has free rotation and a tetrahedral conformation. Its chemical structure can be written as below, in the common representations used for organic molecules.
Occurrence: Propane is found as a constituent of natural gas. It is also present in crude oil together with butane, methane, butylene, isobutylene and others where is extracted from distillation.
Preparation: Propane is producing by the distillation of crude oil or by extraction from natural gas. It is not largely synthesized by chemical industry and there is a few methods for producing it. In crude oil extraction, it is a sub-product in the process to obtain gasoline and other more commercial substances and it is removing to avoid pipelines problems.
Physical properties: Propane is a colorless and odorless gas, but it is shipped as liquefied compressed gas. These melting and boiling point are -187.6 ºC and -42.1 ºC, respectively. Its density is 2.009 g mL-1. Propane, in a pure form or when combined with methane, ethane or propane, can easily ignite forming vapors lighter than air. It is not soluble in water, but is slightly soluble in acetone, ethanol and more soluble in ether, chloroform and benzene.
Chemical properties: Propane is

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Retrieved Text: Alkanes are the simplest group of hydrocarbons. They have the general formula CnH2n+2. The pages have been ordered by the number of carbon atoms in each molecule.
Wikimedia Commons has media related to Alkanes.
This page was last changed on 12 March 2019, at 08:30.

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Retrieved Text: 1. Petroleum and natural gas are largely mixtures of different alkanes. On refining, they give liquefied petroleum gas (LPG), gasoline, kerosene, diesel, furnace oil and wax which are used as fuels.
2. Some higher alkanes are used as lubricating oils and as vaseline.
3. Alkanes are used as starting materials for the preparation of many other useful organic compounds. For example, methane on chlorinate on gives chloromethane, dichloromethane, trichloromethane (chloroform) and tetrachloromethane.
4. Carbon formed during decomposition of methane is in the form of finely divided particles and is known as carbon black. Carbon black is used for making printer’s ink and paints. It is also used in rubber industry.
5. Alkanes are also used as source of hydrogen.

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Retrieved Text: The research team includes, from left, Stasik Popov, Alex Bagdasarian, Hosea Nelson and Brian Shao. Nelson, the study's senior author, says there was surprising chemistry behind the reaction.
For more than a decade in the middle of the 20th century, chemists debated exactly what “carbocations” — molecules with a positively charged carbon atom — looked like. What is known as the “classical view,” which was taught at the beginning of that century, stated that the carbon in these molecules held the charge; the “non-classical view” held that the charge could also be shared by other nearby atoms. Both theory and experiment eventually proved that non-classical carbocations existed, and the debate faded away. Even if these structures exist, most chemists believed, they had no practical relevance.
Now, UCLA researchers have discovered a chemical reaction — that might someday be used to process petroleum into useful compounds — in which non-classical carbocations play key roles. The results, published July 27 in the journal Science, underscore the importance of non-classical cations — ions with fewer electrons than protons, and thus a positive charge. The findings also offer a new reaction to process alkanes, chemicals found in methane and propane gases that are notoriously hard to convert to other products.
“There’s both this reaction with a lot of practical potential, and this surprising chemistry behind the reaction,” said Hosea Nelson, a UCLA assistant professor of chemistry and biochemistry and senior author of the study.
“Now we have shown the importance of these species in explaining reactivity and selectivity,” said Kendall Houk, UCLA’s Saul Winstein

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Retrieved Text: In organic chemistry, compounds composed of carbon and hydrogen are divided into two classes: aromatic compounds, which contain benzene and other similar compounds, and aliphatic compounds (G. aleiphar, fat, oil), which do not. In aliphatic compounds, carbon atoms can be joined together in straight chains, branched chains, or rings. They can be joined by single bonds (alkanes), double bonds (alkenes), or triple bonds (alkynes). Besides hydrogen, other elements can be bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine.
The simplest aliphatic compound is methane (CH4). Aliphatics include alkanes such as fatty acids and paraffin hydrocarbons, alkenes (such as ethylene) and alkynes (such as acetylene).
Most aliphatic compounds are flammable, thus allowing hydrocarbons such as methane to fuel Bunsen burners in the laboratory, whereas acetylene is used in welding.
^ International Union of Pure and Applied Chemistry (1995). "Aliphatic compounds". Compendium of Chemical Terminology Internet edition.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Aliphatic_compound". A list of authors is available in Wikipedia.

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Retrieved Text: This page deals briefly with the combustion of alkanes and cycloalkanes. In fact, there is very little difference between the two.
Complete combustion (given sufficient oxygen) of any hydrocarbon produces carbon dioxide and water. It is quite important that you can write properly balanced equations for these reactions, because they often come up as a part of thermochemistry calculations. Some are easier than others. For example, with alkanes, the ones with an even number of carbon atoms are marginally harder than those with an odd number!
With butane (C4H10), you can again balance the carbons and hydrogens as you write the equation down.
Counting the oxygens leads to a slight problem - with 13 on the right-hand side. The simple trick is to allow yourself to have "six-and-a-half" O2 molecules on the left.
The hydrocarbons become harder to ignite as the molecules get bigger. This is because the bigger molecules don't vaporize so easily - the reaction is much better if the oxygen and the hydrocarbon are well mixed as gases. If the liquid is not very volatile, only those molecules on the surface can react with the oxygen. Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbors and turn to a gas.
Provided the combustion is complete, all the hydrocarbons will burn with a blue flame. However, combustion tends to be less complete as the number of carbon atoms in the molecules rises. That means that the bigger the hydrocarbon, the more likely you are to get a

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Retrieved Text: Rhodococcus opacus R7 is a Gram-positive bacterium isolated from a polycyclic aromatic hydrocarbon contaminated soil for its versatile metabolism; indeed the strain is able to grow on naphthalene, o-xylene, and several long- and medium-chain n-alkanes. In this work we determined the degradation of n-alkanes in Rhodococcus opacus R7 in presence of n- dodecane (C12), n- hexadecane (C16), n- eicosane (C20), n- tetracosane (C24) and the metabolic pathway in presence of C12. The consumption rate of C12 was 88%, of C16 was 69%, of C20 was 51% and of C24 it was 78%. The decrement of the degradation rate seems to be correlated to the length of the aliphatic chain of these hydrocarbons. On the basis of the metabolic intermediates determined by the R7 growth on C12, our data indicated that R. opacus R7 metabolizes medium-chain n-alkanes by the primary alcohol formation. This represents a difference in comparison with other Rhodococcus strains, in which a mixture of the two alcohols was observed. By GC-MSD analysis we also identified the monocarboxylic acid, confirming the terminal oxidation.
Moreover, the alkB gene cluster from R. opacus R7 was isolated and its involvement in the n-alkane degradation system was investigated by the cloning of this genomic region into a shuttle-vector E. coli-Rhodococcus to evaluate the alkane hydroxylase activity. Our results showed an increased biodegradation of C12 in the recombinant strain R. erythropolis AP (pTipQT1-alk R7) in comparison with the wild type strain R. erythropolis AP. These data supported the involvement of the alkB gene cluster in the n-alkane degradation in the R7

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Retrieved Text: The covalent bond ( a pair of shared electrons) is the most common form of linkage between atoms in organic chemistry and biochemistry.
Each element has its own characteristic number of bonds : its valency.
Each line represents a covalent bond, to be used to combine with other atoms.
Actually this is an over-simplification because these are only 2-dimensional. In fact, the 4 bonds of carbon are at about 109º to each other but in 3 dimensions. Another way of saying this is that the 4 bonds are each directed towards the corners of a regular tetrahedron (formed from 4 equilateral triangles), with the carbon atom in the centre!
Carbon is special, because of its four bonds which enable it to combine with other carbon atoms and form a chain. The other elements H, O, N etc are unable to form giant structures on their own.
The term organic has several connotations. Originally it meant something derived from a living organism plant or animal, rather than of mineral origin: inorganic.
Then it became used by chemists to cover compounds of natural origin which were found to be based on carbon, and the term was extended to cover similar and more complex compounds produced artificially, and often containing other elements.
With this proviso, the term organic may be used without much confusion between biologists and chemists (and, indeed biochemists)!
More recently, it has been used in a more general way to describe consumer products and production processes which are not based on chemical fertilisers or other artificial chemicals. In this sense, there is scope for

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Retrieved Text: The alkanes and cycloalkanes, with the exception of cyclopropane, are probably the least chemically reactive class of organic compounds. Alkanes contain strong carbon-carbon single bonds and strong carbon-hydrogen bonds. The carbon-hydrogen bonds are only very slightly polar; therefore, there are no portions of the molecules that carry any significant amount of positive or negative charge that can attract other molecules or ions. Alkanes can be burned, destroying the entire molecule (Alkane Heats of Combustion), alkanes can react with some of the halogens, breaking carbon-hydrogen bonds, and alkanes can crack by breaking the carbon-carbon bonds.

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Retrieved Text: After 250 research articles, Jim Dumesic, a professor of chemical engineering at the University of Wisconsin, Madison, usa, would much rather teach a classroom of seniors than promote a start-up company. But such is the commercial potential of his recent work that Dumesic now courts hard-nosed investors and earnest energy companies for venture capital and strategic partnerships for his start-up company, Virent Energy. The company's mission is to commercialise Dumesic's discovery of a process that could potentially unlock the use of one of the most benign forms of energy ever known -- hydrogen.
In the quest for fuels that produce few or no emissions, hydrogen is a recurring theme. Currently, catalytic steam reforming of methane provides for most of the world's hydrogen needs. The thermal energy required to operate the process at temperatures as high as 800c is costly and causes substantial emissions of carbon dioxide. Moreover, once hydrogen is stripped off methane, the residual carbon is deposited on the catalyst, thus sharply diminishing the overall efficiency of the process.
Dumesic's work promises to be a breakthrough in the quest for cleaner processes to produce hydrogen. Briefly, his method uses a catalyst and moderate temperatures to break glucose down to hydrogen in the presence of water. Glucose is a sugar, which is produced from cornstarch in large quantities. However, cheaper starting materials like sugarcane, corn, rice husk, and waste from paper mills and timber factories could be also used to produce it, because glucose is found abundantly in all biomass. It is this use of cheap and renewable

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Retrieved Text: Hemistry is the technology approximately breaking and forming of bonds among atoms. some of the most very important techniques for natural chemistry is breaking bonds C–H, in addition to C–C in numerous compounds, and basically, in hydrocarbons. between hydrocarbons, saturated hydrocarbons, alkanes (methane, ethane, propane, hexane and so on. ), are specifically appealing as substrates for chemical changes. the reason for this is that, at the one hand, alkanes are the most elements of oil and typical fuel, and hence are the important feedstocks for chemical undefined. nevertheless, those components are recognized to be the fewer reactive natural compounds. Saturated hydrocarbons should be referred to as the “noble gases of natural chemistry” and, if this is the case, the 1st consultant in their kinfolk – methane – could be in comparison with tremendous inert helium. As in all comparisons, this parallel among noble gases and alkanes isn't really totally actual. certainly the differences of alkanes, together with methane, were identified for a very long time. those reactions contain the interplay with molecular oxygen from air (burning – the most resource of energy!), in addition to a few mutual interconversions of saturated and unsaturated hydrocarbons. although, these kind of adjustments take place at increased temperatures (higher than 300–500 °C) and are typically characterised by way of a scarcity of selectivity. The conversion of alkanes into carbon dioxide and water in the course of burning is a really worthwhile approach – yet now not from a chemist perspective.
Hybrid fabrics have at the moment an excellent influence on a

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Retrieved Text: WHY ARE THERE LOTS OF SERIES of ORGANIC COMPOUNDS?
8. Introduction to General Organic Chemistry - Why so many series of organic compounds?
Why are there so many different organic molecules? What is a functional group in organic chemistry? What is a homologous series in organic chemistry? The term 'homologous series' is explained with a general definition or descriptions and illustrated with examples you may, or may not have come across, but you will by the end of your GCSE/IGCSE chemistry course! You might have already come across several organic molecules e.g. methane an alkane, ethene an alkene, ethanol an alcohol, ethanoic acid a carboxylic acid and ethyl ethanoate an ester. This page gives you some idea why such a variety of different molecules can exist based on carbon atoms combined with those of hydrogen, oxygen and nitrogen etc. The different types of organic molecules are classified in what are called homologous series. These revision notes on homologous series of organic compounds and the structure of functional groups in organic chemistry, should prove useful and are designed for the NEW AQA GCSE 9-1 chemistry, Edexcel GCSE 9-1 chemistry & OCR GCSE 9-1 chemistry (OCR Gateway Science & OCR 21st Century Science), in fact any GCSE (9–1), (9-5) & (5-1) science courses.
8. Why are there many families of organic compounds? - variety !
You need to be able to explain that the vast array of natural and synthetic organic compounds occur due to the ability of carbon to form families of similar compounds, 'linear' straight chains, branched chains and rings

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Retrieved Text: Covalent bond or Molecular bond or Homopolar bond : A chemical bond formed between two non-metallic elements by the mutual sharing of one or more electron pairs is called covalent bond.
Covalency : The number of electron pairs which an atom of an element mutually shares with another atom or atoms of the same or different elements, so as to acquire a stable configuration like noble gases, is called co valency.
Properties of covalent (molecular) compound : (i) They have low melting point and boiling point. (ii) They have low density, i.e., their density is generally less than that of water. (iii) They are gaseous or volatile liquids or soft solids. (iv) They are insoluble in water, but soluble in organic solvents. (v) They are generally bad conductors of electricity.
Diamond is the purest crystalline form of carbon which is the hardest naturally occurring substance.
Other pure crystalline forms of carbon are graphite and fullerenes. In Buckminster- fullerene, each molecule has 60 atoms arranged in hexagons and pentagons.
Organic Chemistry : The branch of chemistry dealing with carbon compounds other than carbon monoxide, carbon dioxide and carbonates is called organic chemistry.
Catenation : The property of carbon atoms to link with other carbon atoms or the atoms of other elements with single, double or triple covalent bonds, so as to form large number of compounds is called catenation.
Saturated organic compounds : Organic compounds in which all the four valencies of carbon atoms are satisfied by single covalent bonds, are called saturated organic compounds.
Unsaturated organic compounds : Organic compounds in which a double

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Retrieved Text: A new material, designed and patented by researchers at Berkeley Lab, converts ethane to ethanol with an efficiency that could cut natural-gas refining costs.
Xiao and Jeffrey Long, scientist in Berkeley Lab’s Materials Sciences Division and professor of chemistry at the UC Berkeley focused this project on converting ethane to ethanol.
Ethanol is a potential alternative fuel that burns cleaner and has a higher energy density than other alternative fuels like methanol. One problem with ethanol, however, is that current methods for production require extreme heat, which makes it expensive.
The innovation came when Long and Xiao designed a material called Fe-MOF-74, in a class of materials called metal-organic frameworks or MOFs. Because of their cage-shaped structures, MOFs boast a high surface area, which mean they can absorb extremely large amounts of gas or liquid compared to the weight of the MOF itself.
Since MOFs are essentially structured like a collection of tiny cages, they can capture other molecules, acting as a filter. Additionally, they can perform chemistry as molecules pass through the cages, becoming little chemical factories that convert one substance to another.
It’s this chemical-conversion feature of MOFs that Long and Xiao took advantage of. Ethane is a molecule made of two carbon atoms where each atom is surrounded by atoms of hydrogen. Ethanol is also made of two carbon atoms bonded to hydrogen atoms, but one of its carbon atoms is also bonded to a hydrogen-oxygen ion called a hydroxyl.
Previous attempts to add a hydroxyl ion to ethane to make ethanol have required high pressure and high temperatures

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Retrieved Text: The term chlorinated alkane (CA) covers a wide range of liquids and solids from C10 to >C24 and containing 30-72% chlorine content. Properties differ significantly across this range and for this reason, they are best considered in three separate groups.
The C10-13 liquid products from 40-72% Cl content.
The C14-17, C18-20 and chlorinated alkane wax liquids from 40-60% Cl content.
The powdered chlorinated alkane waxes of >69% Cl content.
CAs have very low vapour pressure with the most volatile (C10-13 types) < 10-3 mbar. They are chemically very stable but dehydrochlorinate on heating at high temperatures (or for prolonged periods). Such dehydrochlorination can also occur upon prolonged exposure to sunlight.
All CAs have a low solubility in water but C10-13 up to 150 μg/l is significantly more soluble than other classes, which show decreasing solubility with increasing chain length (down to <5 μg/l).
Studies have confirmed that CAs adsorb strongly onto suspended materials/ sediments in an aquatic environment. However, unabsorbed or solutions at the lower solubility limit will degrade without added reagents.
It is noteworthy that only very low levels of chlorinated alkanes have ever been found in the environment. Analysis of rivers in industrialised parts of the UK has shown levels in the range 0 to 2 µg/l with short-chain chlorinated alkanes typically accounting for one-quarter to one-third of the total amount present. Higher levels (typically 0 to 10 mg/kg) have been found in those sediments collected from areas closer to industry.
In areas that are further from industry, chlorinated alkanes were either found at signifcantly lower levels or could not be detected

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Retrieved Text: Take the prefix that corresponds to the total number of carbon atoms in the molecule (see naming alkanes in the alkanes page) and add anoic acid to form the name, e.g. CH3COOH is ethanoic acid.
With all these reactions a metal carboxylate salt is formed (e.g. sodium ethanoate).
When carboxylic acids are mixed and heated with alcohols, with a little concentrated sulphuric acid as a catalyst to remove the water product, esters are produced.
The reaction needs to be conducted in distillation appartus so that the product can be separated from the carboxylic acid starting material.
To name an acyl chloride take the prefix that corresponds to the total number of carbon atoms in the molecule (see naming alkanes in the alkanes page) and add anoyl chloide to form the name, e.g. CH3CH2COCl is propanoyl chloride.
Acyl chlorides perform the same reactions as their parent carboxylic acids, except that they react at room temperature and generate hydrogen chloride as a byproduct. They give very exothermic reactions. They must be kept in a dry atmosphere as they will react with the slightest amount of moisture to regenerate the carboxylic acid.
The carboxylic acid is refluxed with a dehydrating agent, such as phosphorus pentoxide (P2O5) and the product is distilled from the reaction mixture.
To name an acid anhydride take the prefix that corresponds to the total number of carbon atoms in the parent carboxylic acid (see naming alkanes in the alkanes page) and add anoic anhydride to form the name, e.g. (CH3CH2CO)2O is propanoic anhydride.
As with acyl chlorides, they perform the same reactions as

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Retrieved Text: describe the general nature of petroleum deposits, and recognize why petroleum is such an important source of organic compounds.
explain, in general terms, the processes involved in the refining of petroleum.
define the octane number of a fuel, and relate octane number to chemical structure.
The refining of petroleum into usable fractions is a very important industrial process. In the laboratory component of this course, you will have the opportunity to compare this industrial process to the procedure as it is performed in the laboratory.
Petroleum is converted to useful products such as gasoline in three steps: distillation, cracking, and reforming. Recall from Chapter 1 "Introduction to Chemistry" that distillation separates compounds on the basis of their relative volatility, which is usually inversely proportional to their boiling points. Part (a) in Figure 3.8.1 shows a cutaway drawing of a column used in the petroleum industry for separating the components of crude oil. The petroleum is heated to approximately 400°C (750°F), at which temperature it has become a mixture of liquid and vapor. This mixture, called the feedstock, is introduced into the refining tower. The most volatile components (those with the lowest boiling points) condense at the top of the column where it is cooler, while the less volatile components condense nearer the bottom. Some materials are so nonvolatile that they collect at the bottom without evaporating at all. Thus the composition of the liquid condensing at each level is different. These different fractions, each of which usually consists of a mixture of compounds with similar numbers of carbon atoms, are

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Input Text: Read the passage below and choose the right answer to the following question (choices are alkane with fewer carbon atoms or alkane with more carbon atoms? ):

Alkanes with more carbon atoms have higher boiling and melting points, so some of them are solids at room temperature.


Kathy did some experiments on two different alkanes and one of the alkanes had twice as many carbon atoms than the other. She would notice that which alkane would require a lower temperature to melt alkane with fewer carbon atoms or alkane with more carbon atoms??

Target Text: alkane with fewer carbon atoms

#### Retrieved Documents ####

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: Because they are saturated compounds, the organic, hydrocarbon compounds, alkanes, tend to show very little reactivity. However, there are a few reactions that alkanes can and do undergo under specific conditions. These reactions include combustion, substitution and cracking. The reactions of alkanes are very important in everyday life.
Combustion is the most important reaction of alkanes. Alkanes burn in oxygen to form carbon dioxide and water vapor. If there is insufficient oxygen for the reaction, carbon monoxide and sometimes even carbon is formed instead of carbon dioxide. In actuality, there is always a certain amount of carbon monoxide formed in the process.
This is the reaction that occurs in internal combustion engines. It is the production of these gases, carbon dioxide and water vapor, and even the carbon monoxide, that allows the useful work of engines.
Very large alkanes are not as useful to human as smaller, short-chained ones. As a result, large alkanes are often cracked to produce smaller, more useful alkanes. During this process, alkenes and hydrogen gas may also be formed. The cracking of alkanes is carried out at 450 degrees celcius over an aluminum oxide or silicon oxide catalyst.
Alkanes can be converted to halogenoalkanes via substitution. This reaction only occurs in light or at high temperatures. As the name suggests, a replacement is made. One or more hydrogen atoms on the alkane is replaced by one or more halogen atoms. This reaction occurs mainly with chlorine, bromine and iodine. The halogen, fluorine, however, does not form halogenoalkanes having reacted with alkanes. Instead, carbon and hydrogen

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Retrieved Text: Alkenes. Showing top 8 worksheets in the category - Alkenes. Some of the worksheets displayed are Naming and drawing alkenes work and key, Alkenes and alkynes work and key02 25 10, Work, Alkanes and alkenes work, Chapter 8, Work alkenes, Chem1002 work 3 addition reactions model 1 addition, Naming alkenes work cr 305 h3c ch3.
Alkenes and Alkynes Worksheet and Key 1. Draw the line bond structures for the following alkenes, cyclic alkenes, and alkynes: a) alkenes that contain 4 carbon atoms (three possible) b) cyclic alkenes that contain 4 carbon atoms (three possible) c) alkynes that contain 4 carbon atoms (two possible, neither of them are cyclic alkynes) 2.
Naming Alkanes Alkenes And Alkynes. Displaying all worksheets related to - Naming Alkanes Alkenes And Alkynes. Worksheets are Naming and drawing alkenes work and key, Naming alkanes, Naming alkynes work 1 c4 305, Work naming and drawing alkanes, Naming alkanes alkenes and alkynes quiz 70, Alkenes and alkynes work and key02 25 10, Work for organic chemistry, Naming alkanes work 1.
Organic Nomenclature - Alkanes, Alkenes, Alkynes Naming organic compounds can be a challenge to any chemist at any level. Historically, chemists developed names for new compounds without any systematic guidelines. In this century, the need for standardization was recognized.

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Retrieved Text: The numerous organic compounds can be grouped into a comparatively small number of series or families of compounds known as homologous series. The simplest series of compounds in organic chemistry is the alkanes. We shall study this series to illustrate what a homologous series means.
The alkanes are a series of hydrocarbons with a general molecular formula of CnH2n + 2, where n is a whole number with a value of one or more.
From the table below, we see that each individual member of the alkane series differs from the preceding or the following member by one carbon atom and two hydrogen atoms, i.e. –CH2– group. Such a family of compounds is known as a homologous series and each individual member is referred to as a homologue.
A homologous series is a family of organic compounds which follows a regular structural pattern, in which each successive member differs in its molecular formula by a –CH2 – group.
Other homologous series include the alkenes, CnH2n, the alkanols, CnH2n+1 OH, and the carboxylic acids, CnH2n+1 COOH. Homologous series have the following common characteristics.
General Molecular Formula: All members share a general molecular formula, i.e., CnH2n + 2 for the alkanes, CnH2n for the alkenes, and so on.
Difference Between Successive Homologues: Each successive member in such a series differs in its molecular formula by the addition of a –CH2– group and in its relative molecular mass by an increase of 14.
Physical Properties: The physical properties of the members change gradually as the number of carbon atoms per molecule increases. For example, the boiling

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Retrieved Text: Alkanes are hydrocarbons that only consist of single bonds. The ratio of carbon atoms to hydrogen atoms in alkanes is always in the form of n: 2n+2.
Alright. Let's talk about alkanes. And alkanes are hydrocarbons, compounds consisting of hydrogen and carbon, that only consist of single bonds, okay? Just single bonds in this carbon chain, this carbon back bone. So the formula for this is going to be CNH2N+2. Okay. So let's talk about several different types of alkanes you might see and come across.
So the first one, the simplest one is methane. Methane is CH4 consisting of one carbon and four hydrogen. And this is [IB] when you use methane, you [IB] this is like a natural gas, gas that might come from our body, something like that is methane. Okay? And notice the prefix meth, is dealing with one carbon, okay?
Next one is ethane. Ethane is dealing with two carbons. The prefix eth, is talking about two carbons and this is typically using c talking about different types of reactions [IB] and some things like that. This is ethane is typially used as a catalyst. Meaning that it helps the reaction move along. In fact three carbons we're going to take the three carbon chain it's going to have a prefix of prop. Meaning three carbons. And this is used, and you're talking about propane gas, propane tanks and things like that. You've probably heard of that when you go camping. You use that with fuel, those are you simplest fuel used for cooking

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: The increasingly large number of organic compounds identified with each passing day, together with the fact that many of these compounds are isomers of other compounds, requires that a systematic nomenclature system be developed. Just as each distinct compound has a unique molecular structure which can be designated by a structural formula, each compound must be given a characteristic and unique name.
Such common names often have their origin in the history of the science and the natural sources of specific compounds, but the relationship of these names to each other is arbitrary, and no rational or systematic principles underly their assignments.
A rational nomenclature system should do at least two things. First, it should indicate how the carbon atoms of a given compound are bonded together in a characteristic lattice of chains and rings. Second, it should identify and locate any functional groups present in the compound. Since hydrogen is such a common component of organic compounds, its amount and locations can be assumed from the tetravalency of carbon, and need not be specified in most cases.
 A root or base indicating a major chain or ring of carbon atoms found in the molecular structure.
 A suffix or other element(s) designating functional groups that may be present in the compound.
 Names of substituent groups, other than hydrogen, that complete the molecular structure.
As an introduction to the IUPAC nomenclature system, we shall first consider compounds that have no specific functional groups. Such compounds are composed only of carbon and hydrogen atoms bonded together by sigma bonds (all carbons

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Retrieved Text: Having spent millions and millions of dollars surveying, exploring, appraising, designing, and developing a site, what do we have to show for it? This depends very much on the type of reservoir. ‘Oil and gas’ isn’t just one category (or even two), but covers a very broad range of mixtures defined by their chemical components.
From a commercial point of view, everything in oil or gas can be considered a hydrocarbon, an inert substance, or a contaminant. In the vast majority of reserves, hydrocarbons make up the vast majority of the mass and volume. This is just as well since they are the part we are most interested in. Hydrocarbons are, as the name implies, compounds made entirely of carbon and hydrogen, which come in an astonishing variety of shapes and sizes because of carbon atoms’ tendency to bond together in chains and rings.
The more common type of hydrocarbons is the aliphatic group, consisting of ‘chains’ and most types of ‘rings’. The simplest is methane, which is a gas has just one carbon atom and four carbon atoms. As we add carbon atoms in a line we get ethane, butane, propane, and pentane, all of which are gasses at room temperature; six carbon atoms make up the backbone of hexane, which is a liquid. These form a class of compounds called alkanes, which continue as you add more carbon atoms, forming increasingly viscous liquids and eventually solids (polythene is technically a very large alkane). Variants on the alkanes are the cycloalkanes, which are simple loops; alkenes and

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Retrieved Text: Petroleum is made up of many different hydrocarbons, some of which are in far greater demand than others.
In order to obtain more of the hydrocarbons in greater demand (which are general small molecules), hydrocarbons in lesser demand are broken down through a process known as catalytic cracking.
Alkanes with 15 to 25 carbon atoms per molecule are broken into two smaller molecules, one an alkane and the other an alkene.
The alkene further splits into smaller alkenes until ethylene, propene, or a combination of both is formed.
Thus, ethylene is a major by-product of catalytic cracking.
Catalytic cracking is not sufficient to meet demands for ethylene, and therefore some fractions of petroleum are decomposed completely to produce ethylene through steam thermal cracking.

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Retrieved Text: There are 5 lectures in this section of science wherein you are going to learn about Carbon and its compound. This is a very important chapter of Science and accounts for about 23 marks with periodic classification of elements. In Carbon and its compound You will learn the following as per the syllabus: Covalent bonding in carbon compounds. Versatile nature of carbon. Homologous series, Nomenclature of carbon compounds containing functional groups (halogens, alcohol, ketones, aldehydes, alkanes and alkynes), difference between saturated hydrocarbons and unsaturated hydrocarbons. Chemical properties of carbon compounds (combustion, oxidation, addition and substitution reaction). Ethanol and Ethanoic acid (only properties and uses), soaps and detergents.
This is first lecture of the Carbon and its compound which is the fourth chapter and is very important for SA-2 as it covers about 15-18 marks in exams. In this session you will learn about the Carbon and its properties. As you know carbon is an element and it has 4 valence electrons in its outermost shell, its valence electron are responsible for the entire change in the behavior and thus it forms maximum number of compounds. You will study here the terms covalency, catenation, tetravalency. The you will learn about the occurrence of Carbon. Sharing of electrons by Carbon. Then you will study the properties of hydrogen and how it forms compounds with hydrogen.Occurrence of allotropes of Carbon i.e.,Diamond, Graphite and Buckministerfulerene. You will study the properties of all three isotopes and difference among the three. You will also discuss the term Allotrophy, organic, Inorganic compound, saturated and

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Retrieved Text: Formula and structure: The propane chemical formula is C3H8 and is extended formula is CH3CH2CH2. Its molar mass is 44.097 g mol-1. The molecule is formed by a chain of three carbon atoms which are bound to 3 or 2 hydrogen atoms in order to complete the 4 bonds required to complete the octet of Lewis structure. The carbon atoms are sp3 hybridized, thus the molecule has free rotation and a tetrahedral conformation. Its chemical structure can be written as below, in the common representations used for organic molecules.
Occurrence: Propane is found as a constituent of natural gas. It is also present in crude oil together with butane, methane, butylene, isobutylene and others where is extracted from distillation.
Preparation: Propane is producing by the distillation of crude oil or by extraction from natural gas. It is not largely synthesized by chemical industry and there is a few methods for producing it. In crude oil extraction, it is a sub-product in the process to obtain gasoline and other more commercial substances and it is removing to avoid pipelines problems.
Physical properties: Propane is a colorless and odorless gas, but it is shipped as liquefied compressed gas. These melting and boiling point are -187.6 ºC and -42.1 ºC, respectively. Its density is 2.009 g mL-1. Propane, in a pure form or when combined with methane, ethane or propane, can easily ignite forming vapors lighter than air. It is not soluble in water, but is slightly soluble in acetone, ethanol and more soluble in ether, chloroform and benzene.
Chemical properties: Propane is

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Retrieved Text: Alkanes are the simplest group of hydrocarbons. They have the general formula CnH2n+2. The pages have been ordered by the number of carbon atoms in each molecule.
Wikimedia Commons has media related to Alkanes.
This page was last changed on 12 March 2019, at 08:30.

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Retrieved Text: 1. Petroleum and natural gas are largely mixtures of different alkanes. On refining, they give liquefied petroleum gas (LPG), gasoline, kerosene, diesel, furnace oil and wax which are used as fuels.
2. Some higher alkanes are used as lubricating oils and as vaseline.
3. Alkanes are used as starting materials for the preparation of many other useful organic compounds. For example, methane on chlorinate on gives chloromethane, dichloromethane, trichloromethane (chloroform) and tetrachloromethane.
4. Carbon formed during decomposition of methane is in the form of finely divided particles and is known as carbon black. Carbon black is used for making printer’s ink and paints. It is also used in rubber industry.
5. Alkanes are also used as source of hydrogen.

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Retrieved Text: The research team includes, from left, Stasik Popov, Alex Bagdasarian, Hosea Nelson and Brian Shao. Nelson, the study's senior author, says there was surprising chemistry behind the reaction.
For more than a decade in the middle of the 20th century, chemists debated exactly what “carbocations” — molecules with a positively charged carbon atom — looked like. What is known as the “classical view,” which was taught at the beginning of that century, stated that the carbon in these molecules held the charge; the “non-classical view” held that the charge could also be shared by other nearby atoms. Both theory and experiment eventually proved that non-classical carbocations existed, and the debate faded away. Even if these structures exist, most chemists believed, they had no practical relevance.
Now, UCLA researchers have discovered a chemical reaction — that might someday be used to process petroleum into useful compounds — in which non-classical carbocations play key roles. The results, published July 27 in the journal Science, underscore the importance of non-classical cations — ions with fewer electrons than protons, and thus a positive charge. The findings also offer a new reaction to process alkanes, chemicals found in methane and propane gases that are notoriously hard to convert to other products.
“There’s both this reaction with a lot of practical potential, and this surprising chemistry behind the reaction,” said Hosea Nelson, a UCLA assistant professor of chemistry and biochemistry and senior author of the study.
“Now we have shown the importance of these species in explaining reactivity and selectivity,” said Kendall Houk, UCLA’s Saul Winstein

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Retrieved Text: In organic chemistry, compounds composed of carbon and hydrogen are divided into two classes: aromatic compounds, which contain benzene and other similar compounds, and aliphatic compounds (G. aleiphar, fat, oil), which do not. In aliphatic compounds, carbon atoms can be joined together in straight chains, branched chains, or rings. They can be joined by single bonds (alkanes), double bonds (alkenes), or triple bonds (alkynes). Besides hydrogen, other elements can be bound to the carbon chain, the most common being oxygen, nitrogen, sulfur, and chlorine.
The simplest aliphatic compound is methane (CH4). Aliphatics include alkanes such as fatty acids and paraffin hydrocarbons, alkenes (such as ethylene) and alkynes (such as acetylene).
Most aliphatic compounds are flammable, thus allowing hydrocarbons such as methane to fuel Bunsen burners in the laboratory, whereas acetylene is used in welding.
^ International Union of Pure and Applied Chemistry (1995). "Aliphatic compounds". Compendium of Chemical Terminology Internet edition.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Aliphatic_compound". A list of authors is available in Wikipedia.

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Retrieved Text: This page deals briefly with the combustion of alkanes and cycloalkanes. In fact, there is very little difference between the two.
Complete combustion (given sufficient oxygen) of any hydrocarbon produces carbon dioxide and water. It is quite important that you can write properly balanced equations for these reactions, because they often come up as a part of thermochemistry calculations. Some are easier than others. For example, with alkanes, the ones with an even number of carbon atoms are marginally harder than those with an odd number!
With butane (C4H10), you can again balance the carbons and hydrogens as you write the equation down.
Counting the oxygens leads to a slight problem - with 13 on the right-hand side. The simple trick is to allow yourself to have "six-and-a-half" O2 molecules on the left.
The hydrocarbons become harder to ignite as the molecules get bigger. This is because the bigger molecules don't vaporize so easily - the reaction is much better if the oxygen and the hydrocarbon are well mixed as gases. If the liquid is not very volatile, only those molecules on the surface can react with the oxygen. Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbors and turn to a gas.
Provided the combustion is complete, all the hydrocarbons will burn with a blue flame. However, combustion tends to be less complete as the number of carbon atoms in the molecules rises. That means that the bigger the hydrocarbon, the more likely you are to get a

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Retrieved Text: Rhodococcus opacus R7 is a Gram-positive bacterium isolated from a polycyclic aromatic hydrocarbon contaminated soil for its versatile metabolism; indeed the strain is able to grow on naphthalene, o-xylene, and several long- and medium-chain n-alkanes. In this work we determined the degradation of n-alkanes in Rhodococcus opacus R7 in presence of n- dodecane (C12), n- hexadecane (C16), n- eicosane (C20), n- tetracosane (C24) and the metabolic pathway in presence of C12. The consumption rate of C12 was 88%, of C16 was 69%, of C20 was 51% and of C24 it was 78%. The decrement of the degradation rate seems to be correlated to the length of the aliphatic chain of these hydrocarbons. On the basis of the metabolic intermediates determined by the R7 growth on C12, our data indicated that R. opacus R7 metabolizes medium-chain n-alkanes by the primary alcohol formation. This represents a difference in comparison with other Rhodococcus strains, in which a mixture of the two alcohols was observed. By GC-MSD analysis we also identified the monocarboxylic acid, confirming the terminal oxidation.
Moreover, the alkB gene cluster from R. opacus R7 was isolated and its involvement in the n-alkane degradation system was investigated by the cloning of this genomic region into a shuttle-vector E. coli-Rhodococcus to evaluate the alkane hydroxylase activity. Our results showed an increased biodegradation of C12 in the recombinant strain R. erythropolis AP (pTipQT1-alk R7) in comparison with the wild type strain R. erythropolis AP. These data supported the involvement of the alkB gene cluster in the n-alkane degradation in the R7

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Retrieved Text: The covalent bond ( a pair of shared electrons) is the most common form of linkage between atoms in organic chemistry and biochemistry.
Each element has its own characteristic number of bonds : its valency.
Each line represents a covalent bond, to be used to combine with other atoms.
Actually this is an over-simplification because these are only 2-dimensional. In fact, the 4 bonds of carbon are at about 109º to each other but in 3 dimensions. Another way of saying this is that the 4 bonds are each directed towards the corners of a regular tetrahedron (formed from 4 equilateral triangles), with the carbon atom in the centre!
Carbon is special, because of its four bonds which enable it to combine with other carbon atoms and form a chain. The other elements H, O, N etc are unable to form giant structures on their own.
The term organic has several connotations. Originally it meant something derived from a living organism plant or animal, rather than of mineral origin: inorganic.
Then it became used by chemists to cover compounds of natural origin which were found to be based on carbon, and the term was extended to cover similar and more complex compounds produced artificially, and often containing other elements.
With this proviso, the term organic may be used without much confusion between biologists and chemists (and, indeed biochemists)!
More recently, it has been used in a more general way to describe consumer products and production processes which are not based on chemical fertilisers or other artificial chemicals. In this sense, there is scope for

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Retrieved Text: The alkanes and cycloalkanes, with the exception of cyclopropane, are probably the least chemically reactive class of organic compounds. Alkanes contain strong carbon-carbon single bonds and strong carbon-hydrogen bonds. The carbon-hydrogen bonds are only very slightly polar; therefore, there are no portions of the molecules that carry any significant amount of positive or negative charge that can attract other molecules or ions. Alkanes can be burned, destroying the entire molecule (Alkane Heats of Combustion), alkanes can react with some of the halogens, breaking carbon-hydrogen bonds, and alkanes can crack by breaking the carbon-carbon bonds.

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Retrieved Text: After 250 research articles, Jim Dumesic, a professor of chemical engineering at the University of Wisconsin, Madison, usa, would much rather teach a classroom of seniors than promote a start-up company. But such is the commercial potential of his recent work that Dumesic now courts hard-nosed investors and earnest energy companies for venture capital and strategic partnerships for his start-up company, Virent Energy. The company's mission is to commercialise Dumesic's discovery of a process that could potentially unlock the use of one of the most benign forms of energy ever known -- hydrogen.
In the quest for fuels that produce few or no emissions, hydrogen is a recurring theme. Currently, catalytic steam reforming of methane provides for most of the world's hydrogen needs. The thermal energy required to operate the process at temperatures as high as 800c is costly and causes substantial emissions of carbon dioxide. Moreover, once hydrogen is stripped off methane, the residual carbon is deposited on the catalyst, thus sharply diminishing the overall efficiency of the process.
Dumesic's work promises to be a breakthrough in the quest for cleaner processes to produce hydrogen. Briefly, his method uses a catalyst and moderate temperatures to break glucose down to hydrogen in the presence of water. Glucose is a sugar, which is produced from cornstarch in large quantities. However, cheaper starting materials like sugarcane, corn, rice husk, and waste from paper mills and timber factories could be also used to produce it, because glucose is found abundantly in all biomass. It is this use of cheap and renewable

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Retrieved Text: Hemistry is the technology approximately breaking and forming of bonds among atoms. some of the most very important techniques for natural chemistry is breaking bonds C–H, in addition to C–C in numerous compounds, and basically, in hydrocarbons. between hydrocarbons, saturated hydrocarbons, alkanes (methane, ethane, propane, hexane and so on. ), are specifically appealing as substrates for chemical changes. the reason for this is that, at the one hand, alkanes are the most elements of oil and typical fuel, and hence are the important feedstocks for chemical undefined. nevertheless, those components are recognized to be the fewer reactive natural compounds. Saturated hydrocarbons should be referred to as the “noble gases of natural chemistry” and, if this is the case, the 1st consultant in their kinfolk – methane – could be in comparison with tremendous inert helium. As in all comparisons, this parallel among noble gases and alkanes isn't really totally actual. certainly the differences of alkanes, together with methane, were identified for a very long time. those reactions contain the interplay with molecular oxygen from air (burning – the most resource of energy!), in addition to a few mutual interconversions of saturated and unsaturated hydrocarbons. although, these kind of adjustments take place at increased temperatures (higher than 300–500 °C) and are typically characterised by way of a scarcity of selectivity. The conversion of alkanes into carbon dioxide and water in the course of burning is a really worthwhile approach – yet now not from a chemist perspective.
Hybrid fabrics have at the moment an excellent influence on a

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Retrieved Text: WHY ARE THERE LOTS OF SERIES of ORGANIC COMPOUNDS?
8. Introduction to General Organic Chemistry - Why so many series of organic compounds?
Why are there so many different organic molecules? What is a functional group in organic chemistry? What is a homologous series in organic chemistry? The term 'homologous series' is explained with a general definition or descriptions and illustrated with examples you may, or may not have come across, but you will by the end of your GCSE/IGCSE chemistry course! You might have already come across several organic molecules e.g. methane an alkane, ethene an alkene, ethanol an alcohol, ethanoic acid a carboxylic acid and ethyl ethanoate an ester. This page gives you some idea why such a variety of different molecules can exist based on carbon atoms combined with those of hydrogen, oxygen and nitrogen etc. The different types of organic molecules are classified in what are called homologous series. These revision notes on homologous series of organic compounds and the structure of functional groups in organic chemistry, should prove useful and are designed for the NEW AQA GCSE 9-1 chemistry, Edexcel GCSE 9-1 chemistry & OCR GCSE 9-1 chemistry (OCR Gateway Science & OCR 21st Century Science), in fact any GCSE (9–1), (9-5) & (5-1) science courses.
8. Why are there many families of organic compounds? - variety !
You need to be able to explain that the vast array of natural and synthetic organic compounds occur due to the ability of carbon to form families of similar compounds, 'linear' straight chains, branched chains and rings

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Retrieved Text: Covalent bond or Molecular bond or Homopolar bond : A chemical bond formed between two non-metallic elements by the mutual sharing of one or more electron pairs is called covalent bond.
Covalency : The number of electron pairs which an atom of an element mutually shares with another atom or atoms of the same or different elements, so as to acquire a stable configuration like noble gases, is called co valency.
Properties of covalent (molecular) compound : (i) They have low melting point and boiling point. (ii) They have low density, i.e., their density is generally less than that of water. (iii) They are gaseous or volatile liquids or soft solids. (iv) They are insoluble in water, but soluble in organic solvents. (v) They are generally bad conductors of electricity.
Diamond is the purest crystalline form of carbon which is the hardest naturally occurring substance.
Other pure crystalline forms of carbon are graphite and fullerenes. In Buckminster- fullerene, each molecule has 60 atoms arranged in hexagons and pentagons.
Organic Chemistry : The branch of chemistry dealing with carbon compounds other than carbon monoxide, carbon dioxide and carbonates is called organic chemistry.
Catenation : The property of carbon atoms to link with other carbon atoms or the atoms of other elements with single, double or triple covalent bonds, so as to form large number of compounds is called catenation.
Saturated organic compounds : Organic compounds in which all the four valencies of carbon atoms are satisfied by single covalent bonds, are called saturated organic compounds.
Unsaturated organic compounds : Organic compounds in which a double

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Retrieved Text: A new material, designed and patented by researchers at Berkeley Lab, converts ethane to ethanol with an efficiency that could cut natural-gas refining costs.
Xiao and Jeffrey Long, scientist in Berkeley Lab’s Materials Sciences Division and professor of chemistry at the UC Berkeley focused this project on converting ethane to ethanol.
Ethanol is a potential alternative fuel that burns cleaner and has a higher energy density than other alternative fuels like methanol. One problem with ethanol, however, is that current methods for production require extreme heat, which makes it expensive.
The innovation came when Long and Xiao designed a material called Fe-MOF-74, in a class of materials called metal-organic frameworks or MOFs. Because of their cage-shaped structures, MOFs boast a high surface area, which mean they can absorb extremely large amounts of gas or liquid compared to the weight of the MOF itself.
Since MOFs are essentially structured like a collection of tiny cages, they can capture other molecules, acting as a filter. Additionally, they can perform chemistry as molecules pass through the cages, becoming little chemical factories that convert one substance to another.
It’s this chemical-conversion feature of MOFs that Long and Xiao took advantage of. Ethane is a molecule made of two carbon atoms where each atom is surrounded by atoms of hydrogen. Ethanol is also made of two carbon atoms bonded to hydrogen atoms, but one of its carbon atoms is also bonded to a hydrogen-oxygen ion called a hydroxyl.
Previous attempts to add a hydroxyl ion to ethane to make ethanol have required high pressure and high temperatures

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Retrieved Text: The term chlorinated alkane (CA) covers a wide range of liquids and solids from C10 to >C24 and containing 30-72% chlorine content. Properties differ significantly across this range and for this reason, they are best considered in three separate groups.
The C10-13 liquid products from 40-72% Cl content.
The C14-17, C18-20 and chlorinated alkane wax liquids from 40-60% Cl content.
The powdered chlorinated alkane waxes of >69% Cl content.
CAs have very low vapour pressure with the most volatile (C10-13 types) < 10-3 mbar. They are chemically very stable but dehydrochlorinate on heating at high temperatures (or for prolonged periods). Such dehydrochlorination can also occur upon prolonged exposure to sunlight.
All CAs have a low solubility in water but C10-13 up to 150 μg/l is significantly more soluble than other classes, which show decreasing solubility with increasing chain length (down to <5 μg/l).
Studies have confirmed that CAs adsorb strongly onto suspended materials/ sediments in an aquatic environment. However, unabsorbed or solutions at the lower solubility limit will degrade without added reagents.
It is noteworthy that only very low levels of chlorinated alkanes have ever been found in the environment. Analysis of rivers in industrialised parts of the UK has shown levels in the range 0 to 2 µg/l with short-chain chlorinated alkanes typically accounting for one-quarter to one-third of the total amount present. Higher levels (typically 0 to 10 mg/kg) have been found in those sediments collected from areas closer to industry.
In areas that are further from industry, chlorinated alkanes were either found at signifcantly lower levels or could not be detected

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Retrieved Text: Take the prefix that corresponds to the total number of carbon atoms in the molecule (see naming alkanes in the alkanes page) and add anoic acid to form the name, e.g. CH3COOH is ethanoic acid.
With all these reactions a metal carboxylate salt is formed (e.g. sodium ethanoate).
When carboxylic acids are mixed and heated with alcohols, with a little concentrated sulphuric acid as a catalyst to remove the water product, esters are produced.
The reaction needs to be conducted in distillation appartus so that the product can be separated from the carboxylic acid starting material.
To name an acyl chloride take the prefix that corresponds to the total number of carbon atoms in the molecule (see naming alkanes in the alkanes page) and add anoyl chloide to form the name, e.g. CH3CH2COCl is propanoyl chloride.
Acyl chlorides perform the same reactions as their parent carboxylic acids, except that they react at room temperature and generate hydrogen chloride as a byproduct. They give very exothermic reactions. They must be kept in a dry atmosphere as they will react with the slightest amount of moisture to regenerate the carboxylic acid.
The carboxylic acid is refluxed with a dehydrating agent, such as phosphorus pentoxide (P2O5) and the product is distilled from the reaction mixture.
To name an acid anhydride take the prefix that corresponds to the total number of carbon atoms in the parent carboxylic acid (see naming alkanes in the alkanes page) and add anoic anhydride to form the name, e.g. (CH3CH2CO)2O is propanoic anhydride.
As with acyl chlorides, they perform the same reactions as

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Retrieved Text: describe the general nature of petroleum deposits, and recognize why petroleum is such an important source of organic compounds.
explain, in general terms, the processes involved in the refining of petroleum.
define the octane number of a fuel, and relate octane number to chemical structure.
The refining of petroleum into usable fractions is a very important industrial process. In the laboratory component of this course, you will have the opportunity to compare this industrial process to the procedure as it is performed in the laboratory.
Petroleum is converted to useful products such as gasoline in three steps: distillation, cracking, and reforming. Recall from Chapter 1 "Introduction to Chemistry" that distillation separates compounds on the basis of their relative volatility, which is usually inversely proportional to their boiling points. Part (a) in Figure 3.8.1 shows a cutaway drawing of a column used in the petroleum industry for separating the components of crude oil. The petroleum is heated to approximately 400°C (750°F), at which temperature it has become a mixture of liquid and vapor. This mixture, called the feedstock, is introduced into the refining tower. The most volatile components (those with the lowest boiling points) condense at the top of the column where it is cooler, while the less volatile components condense nearer the bottom. Some materials are so nonvolatile that they collect at the bottom without evaporating at all. Thus the composition of the liquid condensing at each level is different. These different fractions, each of which usually consists of a mixture of compounds with similar numbers of carbon atoms, are

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Input Text: Read the passage below and choose the right answer to the following question (choices are Zorb to Krakatoa or or from Beanbag to Krypton? ):

In general, the farther away from the Sun, the greater the distance from one planets orbit to the next.


NASA has sent an unmanned probe to survey a distant solar system with four planets. Planet Zorb is closest to the sun of this solar system, Planet Krakatoa is second closest, Planet Beanbag is third from the sun, and Krypton is the farthest. The probe visits the planets in order, first Zorb, then Krakatoa, then Beanbag and finally Krypton. Did the probe have to fly farther in its trip from Zorb to Krakatoa or or from Beanbag to Krypton??

Target Text: from Beanbag to Krypton?

#### Retrieved Documents ####

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Retrieved Text: NASA might be done with the Space Shuttle, but that doesn’t mean the national space agency has given up on exploring those orbs we call planets that lie yonder. No sir, they in fact have a mission to Jupiter down the road, sending a solar-powered, windmill-shaped spacecraft known as Juno – making it the most distant probe to date that receives its electrical sustenance from the glowing ball of fire that we call the sun.
Juno will sport a trio of tractor-trailer-size solar panels which hopefully, will help it sail towards the largest planet in our Solar System across 2 billion miles. Juno will be launched this coming Friday aboard an unmanned Atlas V rocket.
NASA hopes that Juno’s foray into Jupiter will help them learn more about what could possibly be the oldest planet around in our Solar System, and this will be the first of three high-profile astronomy missions being served up across a time span of four months. Juno will travel for five years before arriving at its intended destination, so hopefully the mathematical calculations involved to help Juno get there are correct, and that no wayward asteroids will smash into Juno halfway there.
Filed in Gadgets >Green. Read more about NASA, Solar, Solar Power and Solar Powered.

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Retrieved Text: Over 1,000 unmanned missions have been sent into space to explore our solar system. NASA has launched both exploration and communication satellites into orbit. The missions have been both directly launched into space from earth and launched from a space shuttle once it was already in space. The first unmanned mission was Explorer 1. This project was launched in January 1958, two month's after Sputnik. This was early on in the space race. A more recent unmanned mission was the Hubble Telescope, which was launched in 1990. The closest planets to earth, Mars, Venus, and Mercury, have been the goals of more than four programs. The first was the Mariner in the sixties and seventies which visited all three of the planets. The Mariner was also the first to make a planetary flyby and a gravity assist maneuver. A gravity assist maneuver is where a satellite uses the gravity and velocity of a planet to reach its destination while simultaneously getting the opportunity for close up pictures of a planet. The Viking 1, was the first successful landing on Mars, and landed in 1976.
Twenty years later, NASA also launched rovers to mars on the Mars Pathfinder. This was also a very successful mission and got a lot of useful data from Mars. The Pioneer 10 visited Jupiter in 1973. Pioneer 10 was also the first spacecraft to leave the solar system in 1983. However, Voyager 2 had passed it in distance from our solar system. Both the Pioneer and Voyager program carried messages to earth. A

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Retrieved Text: Tuesday, July 14, 2015 • After almost a decade, NASA’s New Horizons spacecraft made its closest pass to Pluto. The deep space probe will survey the surface of the icy dwarf-planet and send back photos never before seen. Intersection’s Brendan Byrne talks with the mission’s principal investigator Doctor Alan Stern about the mission.
Monday, July 13, 2015 • NASA’s New Horizons spacecraft is making its closest approach to Pluto Tuesday morning. The deep space probe will survey the surface of the icy dwarf-planet and send back photos never before seen.
Monday, July 13, 2015 • International Space Station astronauts will unpack much needed supplies Monday. Two previous attempts to resupply the station failed – including a SpaceX mission that exploded shortly after liftoff late last month.
Monday, July 6, 2015 • After nearly a decade of traveling through space, NASA’s New Horizons probe is about to arrive at Pluto. On Tuesday it will begin an intensive, weeklong study of the distant world.
Monday, June 29, 2015 • Space X is reviewing every frame of video to find out exactly why its Falcon 9 rocket exploded shortly after liftoff Sunday. Search crews are also on the hunt for fallen debris.
Sunday, June 28, 2015 • A SpaceX Falcon 9 rocket carrying supplies to the International Space Station exploded shortly after takeoff.
UCF Researcher: How Are Planets Formed?
Tuesday, March 3, 2015 • Scientists are missing a key part of information in uncovering how planets are formed in our universe. One University of Central Florida researcher received a grant from NASA to conduct an experiment

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Retrieved Text: The closest rocky planet outside our solar system, which is larger than Earth and the potential gold mine of science data. Even though it is too much hot to visit, and it significantly closer than Kepler but it’s 21 light years away from Earth. The new horizons probe of Nasa has famed for taking recent stunning pictures of Pluto.
If you were on a spaceship and going fast, it’d take you just over 387,000 years to get to HD 219134b from planet Earth. Michael Werner, who is the project scientist for the Spitzer mission at Nasa. He said that, “this exoplanet will be one of the most studied for decades to come.” This exoplanet has been tipped as a perfect observation subject by James Webb Space Telescope of Nasa, which will be launched in 2018. Complex observations into this exoplanet have unveiled that, it is around 4.5 times heavier than planet Earth.
By observing the planet when it passes in front of its star, scientists can observe minor changes in the light, caused by the differing reflections of different chemicals in its atmosphere. Planets like this one belong to a growing list of planets called ‘super Earths’ planets that are similar in makeup but slightly larger than our own planet, a category that includes Kepler 452b. It is also around 1.6 times larger than Earth, and by combining the estimated size and mass, scientists have figured out its density, concluding that the planet is rocky, like our planet and not icy, or gaseous. Even though the planet is

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Retrieved Text: Make a good case for NASA to fund your exploration of one of our planets.
Each team will research at least one planet and create a presentation in order to make a recommendation to NASA that their planet be explored by the next space probe. NASA will provide funding to the group that makes the most compelling argument for their planet based on survivability factors or based on the best plan for building a habitable community on the planet.
Use the following resources to create your project.
Astronomy for Kids: A great site to get a quick overview of a variety Astronomy related subjects.
Exploring the Planets: This site is from the Smithsonian Air and Space Museum. Each planet and feature has it's own page of information AND pictures! Take a look and explore.
National Geographic Solar System: A great site with an overview of our solar system, plus lots of beautiful pictures and illustrations.
Nineplanets.org for Kids and Nineplanets.org: Two great sites in one place. The Kids interface is wonderful for a quick overview and some fun facts and pictures. Step up to Nineplanets.org to find more indepth information.
The Planets and Dwarf Planets: From NASA so you know it's good! It also has a link to see the "Level 2" version of the page if you want to challenge yourself with more complex information.
Solar System Exploration: The Planets: Another beautiful and informative NASA site. Fun to navigate and flush with great information.
Solar System Scope: A cool, interactive model of the solar system. You can zoom in on planets, view interplanetary distances,

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Retrieved Text: Are you looking for an exotic destination to visit this summer? Why not take a virtual trip to an Earth-size planet beyond our solar system with NASA's interactive Exoplanet Travel Bureau?
We live in a universe teeming with exoplanets, or planets outside our solar system. Unfortunately, even the nearest exoplanets are light-years away, so sending spacecraft and humans to these intriguing worlds remains a distant dream.
But on NASA's Exoplanet Exploration website, you can explore an imagined surface of an alien world via 360-degree, interactive visualizations. As you investigate each planet's surface, you'll discover fascinating features, like the blood-red sky of TRAPPIST-1d, or stand on a hypothetical moon of the massive planet Kepler-16b, which appears larger than either of the planet's two suns. The view from each planet's surface is an artist's impression based on the limited data that is available; no real photos of these planets exist.
The newest planet to feature this 360-degree surface visualization is Kepler-186f, an Earth-size planet orbiting a star much cooler and redder than the Sun. Scientists don't know if Kepler-186f has an atmosphere, but with the NASA visualization tool, you can see how the presence or absence of an atmosphere would change the view of the sky from the planet's surface.
Many of the exoplanets featured on the Exoplanet Exploration website were discovered by NASA's Kepler space telescope.
"Because Kepler-186f and the majority of Kepler-discovered planets are so distant, it is currently impossible to detect their atmospheres—if they exist at all—or characterize their atmospheric properties," said Martin Still, program scientist for NASA's newest space-based

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Retrieved Text: The TESS spacecraft is expected to discover more than 20,000 alien worlds orbiting distant stars.
April 15, 2018, 11:22 a.m.
Ushering in a new age of exoplanet discovery, NASA's TESS, or the Transiting Exoplanet Survey Satellite, is scheduled to launch aboard a SpaceX Falcon 9 rocket on April 18. The space telescope, a successor to the aging and soon-to-be-decommissioned Kepler space telescope, will scan an area of the night sky nearly 400 times larger (roughly 85 percent of the sky) than that covered by its predecessor.
"Kepler was all about doing a census: How common are planets in general? What is the size distribution of planets like? Are Earth-sized planets common?" Stephen Rinehart, the project scientist for TESS at NASA, told The Verge. "TESS is really optimized for knocking on doors in the neighborhood and saying, 'Hi, how are you? What is this planet actually like?'"
Much like Kepler, TESS will search for exoplanets using something called transit photometry. A transit occurs when a planet passes in front of its host star. This in turn slightly decreases the brightness of the star, creating a signature that TESS's four wide-field CCD cameras will be able to detect. Over the course of its two-year prime mission, TESS is expected to study over 200,000 of the brightest dwarf stars (similar to our own sun) in the closest 300 light-years around Earth.
"We're going to look at every single one of those stars," mission's chief scientist George Ricker of the Massachusetts Institute of Technology, told Phys.org. "All astronomers for centuries to come are really going

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Retrieved Text: Nasa scientists are expected to make history today when they attempt the most distant fly-by of a celestial body yet.
Shortly after 9.30am UAE time, the New Horizons probe will zip past a mysterious 30 kilometre-wide object nicknamed Ultima Thule, which lies about 6.5 billion kilometres from Earth. That’s more than 2 billion kilometres beyond the outermost planet, Neptune.
To put the encounter into perspective, if our planet were shrunk to the size of an orange, the fly-by would be happening more than 50km away.
Yet such is the skill of its controllers, the probe is expected to zoom safely by the object at about 50,000kph, take crystal-clear pictures and then beam them back to Earth.
Even travelling at the speed of light, it will take six hours for the images to cross the void between the probe and its home planet.
This is no mere New Year Day’s stunt, however. Those images will be pored over by astronomers trying to solve one of the greatest mysteries in science: how our solar system was formed.
Ultima Thule – Latin for a place beyond the known world – is a Kuiper Belt object, belonging to a vast band of primordial debris that has been silently orbiting the Sun for billions of years far beyond the known planets. Despite being under the influence of the Sun’s gravitational field, the object is expected to have remained unsullied by the events that took place about 4.6 billion years ago, when the major planets began to take shape.
As such, Ultima Thule is probably the most pristine relic

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Retrieved Text: LONDON: A dwarf planet half the size of Britain has been found tumbling through space in the most distant reaches of the solar system.
The giant ball of rock and ice lies nine billion kilometres away on an orbit that swings far beyond the realm of Neptune, the most remote of the fully-fledged planets in our cosmic vicinity.
Astronomers first noticed the new world when it appeared as a bright spot moving slowly across a sequence of images taken in September 2015 by a telescope on Mauna Kea in Hawaii for the Outer Solar System Origins Survey (OSSOS).
In a formal note released on Monday, the International Astronomical Union (IAU) designated the dwarf planet 2015 RR245. The name will be replaced when astronomers come up with a better one.
While discussions have begun about possible names for the object, Bannister said it was too early to share them. The scientists can propose a name only when the dwarf planet’s orbit has been observed for several years and its trajectory more clearly defined. The name will then be voted on by an IAU committee. “As long as the proposal is reasonable and a bit mythological, it’s generally fine,” Bannister said.
In an act of linguistic gymnastics, the IAU created the term “dwarf planet” in 2006 to describe heavenly bodies that it decided were not proper planets. Pluto became the first dwarf planet that year, when IAU members voted to demote it from full planetary status. A dwarf planet must circle the sun and be large enough to be rendered spherical by its

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Retrieved Text: NASA announced a new system of Exoplanets, which are Earth-size, and could potentially hold life.
NASA announced a new system of Exoplanets, which are Earth-size, and could potentially hold life.These exoplanets are located outside of our solar system and orbit a star, which is why they are named so. So why is the discovery of these Exoplanets such a big deal, and what should you know about them? We break down the facts.
First: A system of seven planets in a system called TRAPPIST-1 is the highlight of this discovery. NASA has named the system of planets after the ‘Transiting Planets and Planetesimals Small Telescope,’ which is located in Chile. This telescope first discovered three of the planets in this system in May 2016.
According to NASA, along with the assistance of other big telescopes, and the European Space telescope called Spitzer, the existence of two of these planets was confirmed. In addition to these two, five more planets were discovered by Spitzer. NASA is now putting the total number of planets in this system at seven.
Second: The star in TRAPPIST-1 is classified as an ultra-cool dwarf, which NASA points out is in contrast to our Sun. The ultra-cool dwarf has a lower mass than the Sun, and also much lower temperatures. What this means is even if planets are orbiting close to the dwarf sun, it is so cool that liquid water will be able to survive on these planets.
The ultracool star shines 200 times dimmer than our sun, so you’d have twilight at all times on these

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Retrieved Text: A flyby of Ultima Thule, a small, icy world located in the outer reaches of the Solar system, has been successfully completed by NASA’s New Horizons probe. Flying by the rock in the early hours of New Year’s Day, the probe sent a signal to the mission team on Earth to confirm its accomplishment. The signal, though, took some 14 hours to reach Earth.
The probe’s encounter with the Ultima Thule occurred about 6.5 billion kilometres from Earth, making it the “the most distant flyby” of an object in the Solar System by a man-made probe.
According to NASA, the spacecraft gathered several gigabytes of images and other data during the pass, but it will take several months to download the data completely.
“New Horizons holds a dear place in our hearts as an intrepid and persistent little explorer, as well as a great photographer. This flyby marks a first for all of us — APL, NASA, the nation and the world — and it is a great credit to the bold team of scientists and engineers who brought us to this point,” said Johns Hopkins Applied Physics laboratory director Ralph Semmel.
Ultima Thule is located in the Kuiper belt – the region of primordial objects comprised of dwarf planets, icy rocks and debris left over from the formation of the solar system about 4.6 billion years ago. This region lies more than two billion kilometres beyond Neptune and about 1.5 billion kilometres from Pluto.
New Horizons’ observations indicate that Ultima Thule is about 32 kilometres long and 16 kilometres wide.

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Retrieved Text: The known universe just got a lot bigger as the Kepler spacecraft has discovered over a thousand new planets orbiting distant stars. In July 2015, the space telescope identified 4,302 potential exoplanets — and further analysis has revealed that 1,284 of those candidates have a 99% likelihood of being a planet. A further 1,327 identified objects are also likely to be planets, but require further study before they can be classified. The study also validated 984 additional planets that had been identified using other techniques. This is the largest number of exoplanets ever identified at one time.
Kepler identifies potential planets by looking for changes in the brightness of other suns that occur when objects pass in front of the star. For four years, the telescope monitored 150,000 stars in a single patch of sky, looking for these slight flickers of light. In the past, individual planet candidates had to be painstakingly verified one by one. This is the first time NASA has used a statistical analysis method to validate multiple planet candidates simultaneously, vastly accelerating the process.
Out of the thousands of now-known exoplanets, only a handful — 550, to be precise — are likely to be rocky planets like Earth based on their size. Out of those, only nine orbit their suns in the habitable zone that would allow liquid water to pool and potentially nourish life. This discovery brings the number of planets capable of possibly harboring life as we know it to just 21 total.
In coming years, it’s likely the number of identified exoplanets

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Retrieved Text: Today’s space history segment combines the recent past and the long past.
In the recent past, 35 years ago today — September 5, 1977 — the Voyager 1 space probe launched from Cape Canaveral aboard a Titan IIIE-Centaur rocket.
Like its sister ship, Voyager 2 (launched about 2 weeks prior), Voyager 1 was designed to study Jupiter and Saturn. Voyager 1’s trajectory was such that it reached both planets before Voyager 2. After its Saturn encounter in 1980, Voyager 1 began making its way toward the edge of the solar system.
Voyager 1 is speeding away from the Sun at a velocity of about 3.50 AU/year toward a point in the sky of RA= 262 degrees, Dec=+12 degrees (35.55 degrees ecliptic latitude, 260.78 degrees ecliptic longitude). Late on 17 February 1998, Voyager 1 became the most distant man-made object from the Sun, surpassing the distance of Pioneer 10.
Data from NASA’s Voyager 1 spacecraft indicate that the venerable deep-space explorer has encountered a region in space where the intensity of charged particles from beyond our solar system has markedly increased. Voyager scientists looking at this rapid rise draw closer to an inevitable but historic conclusion – that humanity’s first emissary to interstellar space is on the edge of our solar system.
In the 1920s and 1930s, Tsiolkovskiy proved especially productive, publishing ten major works clarifying the nature of bodies in orbit, developing scientific principles behind reaction vehicles, designing orbital space stations, and promoting interplanetary travel. He also expanded the scope of studies on many principles commonly used in rockets today: specific

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Retrieved Text: Unmanned instrumented probes obtain scientific information about the moon, other planets, and the space environment. Probes are differentiated from sounding rockets in that they attain at least 6400-kilometer altitudes. When a probe is launched on an escape trajectory-attaining sufficient velocity to travel beyond the earth's gravitational field-it becomes, in effect, a satellite of the sun. The Lunar Orbiter probes, however, were sent into orbit around the earth's natural satellite, the moon.
In May 1960-at the suggestion of Edgar M. Cortright, Assistant Director of Lunar and Planetary Programs-NASA adopted a system of naming its space probes. Names of lunar probes were patterned after land exploration activities (the name "Pioneer," designating the early series of lunar and related space probes, was already in use). The names of planetary mission probes were patterned after nautical terms, to convey "the impression of travel to great distances and remote lands." Isolated missions to investigate the space environment were "assigned the name of the mission group of which they are most nearly a part."3 This 1960 decision was the basis for naming Mariner, Ranger, Surveyor, and Viking probes.
U.S.-German Helios 1 solar probe on the spin table for system test and checkout before mating to the Titan III launch vehicle.
The project was designated "Helios," the name of the ancient Greek god of the sun, by German Minister Karl Kaesmeier. The name had been suggested in a telephone conversation between Minister Kaesmeier and Goddard Space Flight Center's Project Manager, Gilbert W. Ousley, in August 1968.2 NASA had previously used the name for the Advanced Orbiting

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Retrieved Text: A new drawf planet R245????
COULD FIND NEW PLANETS IN THE SOLAR SYSTEM?
Artist's concept of the hypothetical "Planet Nine".
Artist’s impression of the Large Synoptic Survey Telescope (LSST).
of six of the most distant KBOs, and the possible “Planet 9” (aka. “Planet X”).
The orbits of several KBOs provide indications about the possible existence of Planet 9.
The presently known largest small bodies in the Kuiper Belt are likely not to be surpassed by any future discoveries.
Brown and his team have concluded that those days are over.
What is a Drawf Planet?
At least two unknown planets could exist in our solar system beyond Pluto. / Credit: NASA/JPL-Caltech.
Could there be another Pluto-like object out in the far reaches of the Solar System? How about two or more?
called extreme trans-Neptunian objects (ETNO).
Evidence of an ancient collision, perhaps?
Three kerbals touch down on the surface of the small moon Hi'iaka in the depths of the Kuiper Belt.
(see video icon to appreciate this, as KSP cannot render it for larger objects).
After a relatively painless docking high above Hi'iaka's plains, the kerbals prepare to embark on the next leg of their journey: Orcus and Vanth.
Suggest future objects for visiting in the comments. Avoid tiny objects please, and dwarf planets with moons are a big plus.
My rendition of the dark red spot on the surface of Kuiper belt object Haumea.
Artist concept of Haumea, with the correct proportions of the main body and the ring.
and is darker than the surface of the dwarf planet itself.
Credit: Instituto de Astrofísica de Andalucía.
Artist’s impression of the moderately red Quaoar and its moon Weywort.
Artistic

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Retrieved Text: National Aeronautics & Space Administration (NASA), which is an independent agency of the of the United States federal government’s executive branch, has planned to launch Parker Solar Probe in the summer of 2018, aimed to explore the atmosphere of the sun. This probe launch is entirely focused to study outer atmosphere of the Sun and to have an in-depth understanding of how the sun works.
Initially, the name of the probe was Solar Probe Plus, which was renamed to the Parker Solar Probe, honouring astrophysicist Eugene Parker. For the very first time, NASA has named a spacecraft after a living person.
Eugene Parker is an American astrophysicist who in the mid-1950s described the theory on the supersonic solar wind and also predicted solar magnetic field’s Parker spiral shape in the outer solar system. A research paper was published by Eugene Parker that predicted solar wind’s existence in 1958. Before Parker theory revealed that solar wind is the flow of gases from the Sun, it was believed that vacuum is between the planets.
The Parker Solar Probe is 10-feet high and will fly within Sun’s surface’s 6.4 million km into the solar atmosphere.
The objective of the Parker Solar Probe launch is to study the atmosphere of the Sun in detail, put some light on Planet Earth and its place in the solar system.
The probe will be the first human-made probe to face the brutal heat of the sun and the radiation.
The probe mission is aimed at determining the dynamics and structure of the plasma and magnetic fields at solar wind

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Retrieved Text: For the second time in history, a human-made object has reached the space between the stars. NASA’s Voyager 2 probe now has exited the heliosphere – the protective bubble of particles and magnetic fields created by the Sun. According to NASA, Voyager 2 now is slightly more than 11 billion miles (18 billion kilometers) from Earth. Mission operators still can communicate with Voyager 2 as it enters this new phase of its journey, but information – moving at the speed of light – takes about 16.5 hours to travel from the spacecraft to Earth. By comparison, light traveling from the Sun takes about eight minutes to reach Earth.
Voyager 2 is a space probe launched by NASA on August 20, 1977, to study the outer planets. Part of the Voyager program was launched 16 days before its twin, Voyager 1, on a trajectory that took longer to reach Jupiter and Saturn but enabled further encounters with Uranus and Neptune. However, as the mission continued, additional flybys of the two outermost giant planets, Uranus and Neptune, proved possible. As the spacecraft flew across the solar system, remote-control reprogramming was used to endow the Voyagers with greater capabilities than they possessed when they left Earth. Their two-planet mission became a four-planet mission. Their five-year lifespans have stretched to 41 years, making Voyager 2 NASA’s longest running mission.
We wrote about Voyager 1 when NASA received response from the spacecraft 13 billion miles away after 37 years of inactivity. Voyager 1 is NASA’s farthest and fastest spacecraft. It was launched on

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Retrieved Text: After a nine-year voyage, NASA's New Horizons probe has finally reached Pluto, and sent back the first color images of the dwarf planet, as well as its large moon, Charon. Although they're little more than gold blurs in the initial photographs, NASA promises that this is only the first step in truly elucidating our solar system's most mysterious (non)planet.
"This is pure exploration; we're going to turn points of light into a planet and a system of moons before your eyes," said New Horizons principal investigator Alan Stern in a statement.
Stern is referring to New Horizons's closest approach to Pluto on July 15, which will allow the probe to take photos of the dwarf planet in unprecedented detail. New Horizons's suite of seven instruments will also make various scientific observations during its visit to our former ninth planet, such as the surface composition, the temperature, the atmosphere, and the smaller orbiting satellites.
"Scientific literature is filled with papers on the characteristics of Pluto and its moons from ground based and Earth orbiting space observations, but we've never studied Pluto up close and personal," said NASA's John Grunsfeld. "In an unprecedented flyby this July, our knowledge of what the Pluto system is really like will expand exponentially and I have no doubt there will be exciting discoveries."
Because the flyby is relatively brief, and will occur during a singular window of opportunity, New Horizons will cram 100 times as much data as it can possibly send back during the event. It will then send the data back in increments, so

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Retrieved Text: Uranus is the first of the ice giant planets. Its atmosphere, like Saturn and Jupiter’s, is filled with hydrogen and helium, but Uranus’ atmosphere also has high amounts of methane that gives the planet its blue tint as the light reflects off its cold tops.
Like Venus, Uranus rotates east to west, and a single rotation takes a little over 17 Earth hours. The planet has unique axis tilt that causes the planet to appear as if it is rotating on its side. Uranus takes 84 Earth years to complete a single orbit around the Sun. Two sets of rings encircle the planet, with the inner set being narrow and dark and the outer ring, unseen until 2003, is brightly colored.
Uranus has not been an object of significant study by scientists. Most of what is known about Uranus was gathered by the Voyager 2 spacecraft in 1986, the only spacecraft to visit the planet. Other research of the planet has largely been performed with images gathered by the Hubble Telescope.
A new 4-minute film casts digital humans in real extraterrestrial destinations, guided by the timeless words of Carl Sagan.
Scientists had believed that Uranus' orbit was too unstable to play host to an asteroid companion.
These are the first images of the event since NASA Voyager probe snapped images in 1986.
October 11, 2011, 2:34 p.m. by Space.com Inc.
The planet's unique tilt indicates that major impacts were typical for the formation of planets.
February 18, 2011, 6:51 p.m. by Space.com Inc.
A NASA spacecraft heading for Mercury beams back an amazing space photo:

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Retrieved Text: Jack Jonathan Lissauer is a space scientist in the Space Science and Astrobiology Division, NASA Ames Research Center, Moffett Field, Calif. He is a science co-investigator on the Kepler space telescope mission. NASA's Kepler spacecraft will search for Earth-size planets orbiting distant stars following its scheduled 2009 launch. ( http://www.nasa.gov/centers/ames/research/2007/kepler_feature.html) Lissauer is a Consulting Professor at Stanford, teaching advanced-level classes in planetary sciences and astrobiology.
He and his colleagues -- including Geoffrey W. Marcy, professor of astronomy, University of California, Berkeley (http://astro.berkeley.edu/~gmarcy/) -- have discovered four extra-solar planets – planets beyond our solar system. Lissauer and Mark Showalter of the SETI Institute, Mountain View, Calif., in 2003 discovered two moons of Uranus – Mab and Cupid -- as well as two additional rings around the planet – named with the Greek letters Mu and Nu.
Left: Jack Lissauer portrait. Click on the photo for high-resolution image.
Lissauer's research interests include planetary astrophysics; planet and star formation; detection of extra-solar planets; assessing the abundance of habitable planets; rotation of planets and comets; craters on planets and moons; circumstellar disks (disks that revolve around stars); resonances and chaos (gravitational interactions among planets that can change their orbits); and planetary rings and moons.
Lissauer holds a doctorate in applied mathematics granted by the University of California, Berkeley, in 1982. His thesis is entitled "Dynamics of Saturn's Rings." He also has a degree in mathematics from the Massachusetts Institute of Technology, Cambridge, Mass.
Prior to joining NASA, Lissauer was an associate professor (September 1993 - August 1996) and assistant professor (June 1987 - August 1993)

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Retrieved Text: Nasa’s New Horizons spacecraft has beamed home its first close-up images of Ultima Thule, a lump of rock the shape of an unfinished snowman that lies 4 billion miles away on the edge of the solar system.
Taken as the probe sped past the body in the early hours of New Year’s Day, the pictures reveal a dark reddish object about 21 miles long and 10 miles wide that spins on its axis once every 15 hours or so. The colour image of Ultima Thule, revealing its reddish tint, was taken at 05.01 GMT on New Year’s Day from a distance of about 18,000 miles, 30 minutes before the probe made its closest pass of the space rock.
The spacecraft snapped thousands of images of the object, known formally as 2014 MU69, in a fleeting encounter that set a record for the most distant flyby in history. From a billion miles beyond Pluto, it takes data sent at the speed of light about six hours to reach Earth.
“Meet Ultima Thule,” said Alan Stern, the mission’s principal investigator, as he unveiled the images at a press conference on Wednesday. The scientists originally described the object as shaped like a bowling pin, but Stern said he had changed his mind on seeing the new picture. “That bowling pin is gone. It’s a snowman if anything at all,” he said.
The odd shape of Ultima Thule is thought to have come about when swirling ice and dust particles coalesced in the early life of the solar system and eventually led to two

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Retrieved Text: What is the asteroid belt? The vast majority of asteroids in the solar system are found in a region of the solar system out beyond Mars. They form the Asteroid Belt. Others orbit in near-Earth space and a few migrate or are thrown out to the outer solar system by gravitational interactions. The four largest asteroids in the belt are Ceres, Vesta, Pallas, and Hygiea. They contain half the mass of the entire belt. The rest of the mass is contained in countless smaller bodies. There was a theory once that if you combined all the asteroids they would make up the missing “Fifth” rocky planet. Planetary scientists estimate that if you could put all that material together that exists there today, it would make a tiny world smaller than Earth’s moon.
Where is the asteroid belt located? The Asteroid Belt is located in an area of space between the orbits of Mars and Jupiter. That places it between 2.2 and 3.2 astronomical units (AU) from the Sun. The belt is about 1 AU thick. The average distance between objects in the Asteroid Belt is quite large. If you could stand on an asteroid and look around, the next one would be too far away to see very well.
Asteroid Mining. The solar system contains many different types of asteroids, grouped by the minerals they contain. The abundances of precious metals such as nickel, iron, and titanium (to name a few), and water make asteroids an attractive target for mining operations when humans decide to expand their presence

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Retrieved Text: Planet X is the name given to any hypothetical planet yet to be discovered in our Solar System. Percival Lowell originally coined the term back in the early 1900’s. Lowell is the same astronomer who thought he saw canals on the surface of Mars, “proving” the existence of a Martian civilization.
At one time, Uranus and Neptune could have born the Planet X title. Scientists long suspected the existence of a seventh planet due to anomalies in the orbit of Saturn. After Uranus was discovered, anomalies in its orbit hinted at the existence of Neptune, and anomalies in Neptune’s orbit hinted that there might be even more planets beyond it.
Recent data from the Wide-Field Infrared Survey Explorer, a.k.a. WISE, found no evidence of a Planet X, which seemed to put the matter to rest once and for all. There are lots of dwarf planets out there, like Pluto and Eris, but nothing large enough affect Neptune’s orbit in any meaningful way.
Now NASA scientists are proposing the existence of Planet X again to explain anomalous perturbations in the orbits of two of the most distant known dwarf planets. To be fair, WISE failed to detect any Saturn or Jupiter-sized planets. This new Planet X would be much smaller, closer to the size of Earth or Mars.
It seems our Solar System just keeps getting more and more crowded.
Posted by J.S. Pailly on March 28, 2014 in Sciency Words and tagged Percival Lowell, Planet X, WISE Telescope.
I love Science Fiction, can’t wait for more astrological discoveries!

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Retrieved Text: Mars (2 moons - Phobos & Deimos); Liquid Water Asteroids (Millions of minor planets; largest are Ceres & 4 Vesta); reputed to be Rahab (Satan's planet that God shattered).
Planet Nine: Suspected but as yet an undiscovered planet that (along with Neptune) affects the orbits of many dwarf planets and outer-fringe solar system entities.
Rogue Planet: Called SIMP J01365663+0933473 and discovered in 2016 AD. Located 20 light-years from Earth. Mass is 12.7 times greater than Jupiter; size is between being a gas giant planet and a brown dwarf star.
ASASSN-15 (All Sky Automated Survey for Supernovae) magnetar of June 2015. Artist View from an exoplanet.
Asteroid 2015TB145: Near-earth orbit in 2018. Oumuamua: Interstellar Asteroid that entered our solar system in December 2017. Top Harvard astronomer claims it may be a reconnaisance spaceship.
Gliese 581d; Discovered in 2010 AD. Twice the size of Earth. "Mysterious" radio signals noted coming from the planet. Simulation of Gliese 581d Orbit. Distant View and Sunrise on Gliese 581d.
Near-Earth planet called ProximaB orbits red dwarf star Proxima Centauri (closest star to Earth). ProximaB was discovered in 2016 AD.
Galaxy Map View of Core Stars; View from the International Space Station.
Black Hole at the center of Milky Way galaxy. Located 26,490 light-years from the constellations of Ophiuchus, Sagittarius and Scorpius. Coincides with Sagittarius A* (astronomical radio source).

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Retrieved Text: NASA has added a feature to its Exoplanet Exploration website that helps you explore exoplanets.
It’s called the Exoplanet Travel Bureau, and as the name suggests, it aims to give you an idea of what it would be like to travel to a planet outside our solar system.
Since 1992, 3,730 exoplanets have been confirmed as found, with another 4,496 candidates across 2,783 star systems.
The vast majority of them, sadly, aren’t fit for human habitat. They’re mostly too hot, too oxygen-starved, too radioactive or any number of other extreme variables that just aren’t conducive to visitors actually staying alive.
That’s what NASA’s researchers think Kepler 186f might look like. Pretty boring unless you add atmosphere.
“Because Kepler-186f and the majority of Kepler-discovered planets are so distant, it is currently impossible to detect their atmospheres – if they exist at all – or characterize their atmospheric properties,” Martin Still, program scientist for NASA’s newest space-based planet-hunting observatory, the Transiting Exoplanet Survey Satellite (TESS), explains.
If you haven’t visited NASA’s alien worlds website, you’ll find it’s a great rabbit hole. It’s easy to use, and perfectly edited to be engaging for just about any audience.
Among them include the planet being eaten by its own star, a world that is half daylit lava and half permanent darkness, and a blue world where 8600 km/h winds eternally blow shards of glass sideways.
Equally fun is the Universe of Monsters where NASA’s team has identified six planets which would be great homes for classic nightmare creatures, such as TRAPPIST 1b – the perfect planet for werewolves, with

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Retrieved Text: Comment With everyone going ape over the dazzling new crisp pictures from NASA's New Horizons probe of the dwarf freezeworld Pluto, there are few voices asking if it was worth sending out a space probe to the far end of the Solar System – but it wasn't always that way.
When a journey to Pluto was first mooted in the late 1980s, there was a lot of criticism of the idea, both within NASA and definitely within US Congress. After all, it's a small rock in the middle of nowhere – what's the point?
Even as New Horizons got closer, there were naysayers bemoaning the cost of such a mission ($700m, since you asked). Never matter that the entire program costs less than three F-35 fighters – some seem to think that we aren't getting enough bang for our buck and aren't there bigger fish to fry.
While it's fascinating that we're seeing close-up images of another planetary body for the first time, there's a hard science element to the mission that can sometimes be ignored. The fact is, New Horizons has already delivered enough useful new science to justify the time and money spent on the program, and will carry on paying its way for years to come.
Even before the probe had left the laboratory, the scientific payback was starting to come in. New components had to be developed and new materials were needed to get the probe small enough for an easy launch and tough enough to survive the journey. The whole thing had to be engineered

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Retrieved Text: « The days are numbered for the dark matter?
The first to pick up the signals from the probe New Horizons will not be NASA technicians, but experts working at the Canberra Deep Space Communication Complex (CDSCC) CSIRO, which then will send the images directly to the Jet Propulsion Laboratory (JPL). And the company has started the initiative Pluto Time.
We, missing very little arrival of NASA’s New Horizons in the orbit of Pluto . At 13:49 (Italian time) we could say officially that he had explored the entire solar system (at least all the planets), a company that began more than 50 years ago and that certainly will not end with this mission. But the first to pick up the data from the probe (launched January 19, 2006 from Cape Canaveral) will not be NASA technicians, but experts working at the Canberra Deep Space Communication Complex (CDSCC) CSIRO , which then will send the ‘picture directly at the Jet Propulsion Laboratory (JPL).
After 3462 days of the mission, the world will finally know how it’s done Pluto, how big, how to make up its atmosphere and how it interacts with the solar wind. All from 12,500 km from the surface of the dwarf planet (Pluto no longer a planet since 2006). The NASA probe will study in detail even the system of five icy moons orbiting Pluto 134340 (his real name), the first to be studied is Charon, which is also the largest (forms a binary system with the planet nano), slightly smaller than Pluto; follow Hydra and

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Retrieved Text: NASA's Kepler space observatory has found more than 1,200 potential alien worlds since it began hunting for extrasolar planets in 2009.
Observations from the mission's first four months alone have unlocked a flood of exoplanet possibilities, including 54 candidates for habitable worlds orbiting distant stars. Today (Feb. 2) NASA unveiled the latest set of observations from that four-month period.
NASA officials expect the $600 million Kepler observatory to continue staring at its target patch of sky until at least November 2012.
$600 million: The cost of the Kepler planet-hunting mission at its launch in March 2009.
156,000: The number of stars in the constellations Lyra and Cygnus that the Kepler observatory is staring at 24 hours a day, seven days a week, in the search for extrasolar planets. Kepler's field of views covers about 1/400th of the sky.
1,235: The number of potential alien planets that Kepler has discovered. NASA has repeatedly cautioned that all of Kepler's findings must be confirmed by follow-up observations using other space and ground telescopes.
662: The number of planet candidates found by Kepler that would be about the size of Neptune. Neptune has a radius of about 15,388 miles (24,764 km) wide and has a mass that is 17 times that of the Earth, according to NASA.
288: The number of exoplanet candidates discovered by Kepler that are in the super-Earth class. Super-Earths are planets with masses between two and 10 times the mass of Earth, according to NASA.
170: The number of stars that seem to have more than one planetary candidate orbiting them – which would

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Retrieved Text: LOGAN, UTAH -- The Utah State University Research Foundation announced today that it has selected Major General Susan K. Mashiko, USAF(RET) to serve as a member of its Board of Trustees.
LOGAN, UTAH -- When it comes to space exploration, the Space Dynamics Lab at Utah State University plays a big role.
LOGAN, UTAH, August 24, 2016 – The Utah State University Research Foundation and its Space Dynamics Laboratory announced that it has received an indefinite delivery, indefinite quantity contract valued at up to $99.4 million over the next five years from the Department of Defense.
NORTH LOGAN — Kids of Utah State University Space Dynamics Lab employees celebrated the start of construction for a new building with a “skybreaking” by launching model rockets Thursday afternoon.
Does the Solar System Really Have a Ninth Planet?
Caltech researchers Konstantin Batygin and Mike Brown, who initially made the announcement about the possible existence of Planet Nine, have published new findings that have helped narrow down the current location of the mysterious giant looming over Earth in the far outer Solar System.
Thirty-four graduating seniors were honored Friday by the Utah State University Research Foundation and Space Dynamics Laboratory for their work at the two institutions while in college in Logan.
In 2011, astronomers announced that our galaxy is likely teeming with free-floating planets. In fact, these lonely worlds, which sit quietly in the darkness of space without any companion planets or even a host sun, might outnumber stars in our Milky Way Galaxy.
In 2011, astronomers reported our galaxy is likely filled with roaming planets not

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Retrieved Text: After sending the closest pictures of the farther most planet in the solar system, NASA's New Horizons spacecraft seems to be in 'good shape' for the Pluto flyby.
When will the flyby occur?
The historic flyby will take place on Tuesday, 14 July.The closest flyby will be take place at 7:50 am on 14 July (11.50 GMT). At this point, the spacecraft will pass within 9,977 kilometers of Pluto.
After over a nine-year and three billion miles journey, the New Horizons spacecraft will fly past Pluto at 7:49 am EDT on Tuesday, 14 July, at 30,800 miles per hour (49,600 kilometers per hour). With this, New Horizons will become the first ever spacecraft to do a flyby of the dwarf planet.
According to reports by BBC, in the wee hours of Monday, 13 July, New Horizons moved to within a million miles of the planet and is said to be closing in swiftly.
What has the spacecraft done so far?
Before heading for the closest flyby of the dwarf planet, the spacecraft sent back the best photos of the icy planet, and its largest moon, Charon. The spacecraft captured it last and the best image of the planet with four mysterious spots on the planet's surface. The spots are on that side of the planet which always faces the Charon.
What will the spacecraft do during the flyby?
During the flyby, the spacecraft will collect data about the planet's geology, surface composition, temperature and atmosphere. The data will be collected through a set of seven science instruments. The spacecraft will also gather data of

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Input Text: Read the passage below and choose the right answer to the following question (choices are the object with many colliding particles has a lower concentration of particles or the object with many colliding particles has a higher concentration of particles ):

At higher concentrations, particles of reactants are crowded closer together, so they are more likely to collide and react.


Ian sees an object with few colliding particles, and he compares it to another object with few colliding particles. Which is true about the objects the object with many colliding particles has a lower concentration of particles or the object with many colliding particles has a higher concentration of particles?

Target Text: the object with many colliding particles has a lower concentration of particles

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Retrieved Text: I have a problem separating particles colliding with other particles.
Filter demon with "on Collision" option separates only particles hitting/colliding with the object not the other particles.
Any clue how to do it ?
Re: Particle to Particle collision separation - filter/demon script ?

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Retrieved Text: where is my mistake? Particle wont collide with the grid. They should slide or bounce. better both. And why I dont have a preview of my smoke sim?
Last but not least: Where I'm able to find detailed! Tutors with as muach as possible colliding stuff in it. Particles of course.
particles: Add a static solver to your particle dop network with the collision object of your choice. You just have added a collision detect which stores some hit attributes.
smoke: At first glance I think there is something wrong with your dynamic grid. I turned it off and set the bounding box to a proper size and I got some feedback. Maybe start looking there.
Don't even need a static solver, just merge in a ground plane (or other static object) with the right collision relationship on your merge. You can use your own grid I guess but if you want to represent an infinite floor its easier with a ground plane.
could you send me the file please? Dont know some things exactly.
checked it for 3 minutes this morning before work and didn´t save at all.
Do the following: Navigate to the pop network and hit the Ground Plane button in the shelf. Your particles should collide immediately with the ground.
In your autoDop network ( this one with the smoke sim ) just deactivate the auto resize fluid.... node. Resize your fluid Grid a bit. That´s all.

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Retrieved Text: With respect to having objects bounce off one another, I suggest checking out the following links concerning elastic collisions, inelastic collisions, and coefficients of restitution. EDIT: I just noticed that this was covered in another SO question , albeit not specifically for Python.... Is ther a way to know what another object is colliding with? I have a bunch of child objects, each with a trigger collider. I want the parent to be able to know which children are colliding with an object.
Moreover, sprites can be easily created and used to simplify the drawing process and provide a more object-oriented approach to it, and sprite groups provide an efficient way to organize sprites and accomplish tasks such as collision detection. If you are looking to build a simple game in Python or an application with a unique interface, consider using PyGame. how to change wifi password cisco modem dpc2320 So, in this tutorial, I am going to show you how to detect collision between two objects so that you can apply it to your game development project. Here we are going to detect collision with a specific object in Unity 3D with C# programming.
The more complicated problem is how to efficiently detect what objects in a set are overlapping/have collided, without pairwise comparing each object against every other object, which has sub-optimal O(N^2). For this you need a spatial data structure of some kind, like a quad tree. how to draw fur with pastels Collision is knowing when one object has come into contact with another

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Retrieved Text: A particle system is first and foremost driven by attributes. Here are some of the attributes understood by the solvers.
The attributes are listed with the @ style prefix to give the full type. No prefix means float.
There are two suggested methods for creating attributes: POP VOP and POP Wrangle.
In a POP VOP, you can use a Bind Export VOP to write out your desired attribute.
In a POP Wrangle you can use a prototype to specify the attribute and default.
The expression after the equals must be a simple constant expression.
Houdini will use the Cd (diffuse color) point attribute to color particles.
Time in seconds since the particle was born. To get the relative time, useful for fading effects, use @nage.
@age divided by @life. Implicit attribute, you cannot write to this.
Time in seconds the particle is allowed to live. When @age>@life, the particle will be marked dead.
A unique id for the particle that remains the same throughout a single simulation. Always use @id rather than @ptnum to avoid things changing when particles are deleted. Use findattribval() to look up the point number that corresponds with an id.
The particle solver uses the standard v (velocity) attribute as the direction of the particle. Use length(@v) to get the speed of the particle.
Forces on the particle for this frame.
This is multiplied by @pscale to determine the rough shape of the particle for the purpose of rotational inertia.
How much the particle is dragged by any wind effects.
A value from 1 to 2. An exponent of 1 means that a particle is dragged to

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Retrieved Text: The cumulative total of particle hits.
The number of times the particle hit in this detection node.
A path to the object it hit. This is an op: path so it can be used directly by VEX.
The primitive the object hit. Can be -1 if the specific primitive could not be resolved.
The parameteric location on the primitive of the hit. This is not texture uvs. The primuv() VEX function can be used to recover information about the hit location.
The location in space of the collision. Often does not correspond to the current location of the particle as it usually passes through the collision. Also may not correspond to the evaluated location of the hitpath since intra-frame collisions use swept geometry.
The normal of geometry at the time of the collision.
The velocity of the geometry at the time and position of the collision.
When, in seconds, the collision occurred.
You can read the hit attributes directly, or use the POP Collision Behavior node to transform them in some common ways.
This node detects collisions of all particles in the Group field, even if they already collided. So if you're sticking particles, this node will update the hittime of stuck particles at each time step.
To avoid this, you can specify the Group as @stuck=0, so the node only affects particles that aren’t stuck.
In SOP mode, this node only supports collisions with triangles and quads. You can detect collisions with SDFs using the Relationship or DOP Objects and pointing to Static Objects.
This operator modifies the hitnum, hitpath, hitprim, hituv, hitv, hitpos, hitnml, hittime, P, Cd,

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Retrieved Text: [HELP] How to switch the mode of displacement ?
How Can I Make A Platform Lauch My PLayer Into The Air?
How to avoid Character Controller being launched to the air when colliding?
How can I make a flying object follow ground player and stay airborne?
Airplay video play on TV while mirroring is on!
Shaky (jittery) 2D car movement.
How Do I Install Unity 5 on a MacBook Air?
Restrict the particles system, Even when the gameobject is rotating .
Can I use Unity3D in Flash?
Jump in direction while in air?
How to make my vehicle stop from going forward in mid air?

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Retrieved Text: Part 1 – Introduction: Information about what we will be building and what we will not.
Before going into the details, I insist on the fact that the physics system we will build here is not physically correct. We will not resolve collision impact or forces in a realistic way, since this is not the goal here. Instead, our aim is to obtain a simple solution focusing on achieving a good gameplay.
Now that this has been made clear, let’s proceed to the details.
To identify colliders, we will first introduce a new component, the Collider component.
One of the few restrictions we imposed on our game was that all the colliders of objects must have a square shape. Therefore, detecting collisions mostly means detecting intersection between squares.
We will also require a function to check if an object is outside our level to prevent it from going outside of our map area.
Note: You migh wonder why we substract the value 0.5f to coordinates. This is because we assumed that the first tile of our grid was at coordinates (0,0). Therefore, the first tile extends from (-0.5; -0.5) to (0.5;0.5). The same applies to the other borders of our level. Please also note that we assumed each grid cell to be 1-unit wide.
We our now ready to check if an object is colliding another one, or colliding the border of our level.
Before moving an object, our physics sytem will now check if it would result in a colliding position. If so, it will also prevent the colliding object to move.
In the

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Retrieved Text: Here, as promised, is episode nine of Mike Paterson’s “Colliding Particles“.
Nothing to do with zombies, although it could have been.
This entry was posted in Particle Physics, Physics, Science and tagged colliding particles, Higgs, video. Bookmark the permalink.

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Retrieved Text: In ATLAS, the very first component that is reached by colliding particles is the inner detector. As particles collide, their tracks, momentum and charge must be measured with the highest degree of precision. In this interview by ATLAS physicist Steven Goldfarb of colleague Pippa Wells, ATLAS Inner Detector System Project Leader, viewers learn how this measurement is done in the heart of ATLAS. Topics covered include a basic description of the structure of the inner detector, what the detector is trying to do, what types of particles will be able to be seen, how the inner detector records what it sees, what happens to the data collected, the construction and assembly process of the detector, the importance of system testing during assembly, and what would happen if the Higgs particle passed through the detector.

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Retrieved Text: First one needs to know the initial conditions, namely how powerful the collision was: this is done by measuring the remnants of the colliding nuclei in detectors made of high density materials located about 110 meters on both sides of ALICE (the ZDC’s) and by measuring with the FMD, V0 and T0 the number of particles produced in the collision and their spatial distribution. T0 also measures with high precision the time when the event takes place.
An ensemble of cylindrical detectors (from inside out: ITS Pixels (ITS Drift, ITS Strips, TPC, TRD) measures at many points (over 100 just the TPC ) the passage of each particle carrying an electric charge, so that its trajectory is precisely known. The ALICE tracking detectors are embedded in a magnetic field (produced by the huge red magnet !) bending the trajectories of the particles: from the curvature of the tracks one can find their momentum. The ITS is so precise that particles which are generated by the decay of other particles with a very short life time can be identified by seeing that they do not originate from the point where the interaction has taken place (the “vertex” of the event) but rather from a point at a distance of as small as a tenth of a millimeter.
ALICE also wants to know the identity of each particle, whether it is an electron, or a proton, a kaon or a pion. In addition to the information given by ITS and TPC, more specialized detectors are needed: the TOF measures, with

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Retrieved Text: This depiction is, of course, even more utterly balderdashian than all the other boson-pictures combined, because the Higgs is created (and for a short time only) inside the LHC, when other particles collide. While here, one clearly sees two Z-Bosons emotionally colliding, a total figment of imagination.
But I like it anyway, and there's some truth in it, as well, for those to see with their eyes and think in their dreams.

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Retrieved Text: 1. Clustering and Coarsening in a Granular Gas Granular gases are of great scientific and economic relevance. Scientific, because of their tendency to spontaneously separate into dense and dilute regions, which makes them fundamentally different from any textbook molecular gas. Economic, because no less than 5 per cent of the global energy budget is wasted due to problems with granular matter in conveyor belts, sorting machines, mixers, and other industrial machinery. Here we study - experimentally, numerically, and theoretically - the clustering of particles in a vertically vibrated array of N connected compartments. For strong shaking, the particles spread evenly over the compartments, but if the shaking strength is lowered beneath a critical level this uniform distribution gives way to a clustered state, consisting of a few well-filled compartments and a lot of diluted ones. In the course of time, this state coarsens: The smaller clusters are eaten by the larger ones, until finally only one big cluster remains. This coarsening process is exceptionally slow, with the mass of the surviving cluster growing only as the square root of log t.
In this second lecture we turn to the wonderful world of ratchets, which have become a hot topic in recent years. In order to extract mechanical work on a molecular scale (e.g., to make a muscle move), nature uses the concept of a Brownian ratchet: The stochastic forces from a noisy environment are converted into a directed motion. Here we create a "granular ratchet", exploiting the clustering phenomenon from the previous lecture in a slightly adapted

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Retrieved Text: I've also tried with raycasting but none of the pieces moved. I also have one more problem with the OnTriggerStay2D, "else if" part. OnTriggerStay2D should instantiate one of the particles according to puzzle piece is in the correct place or not. But it instantiates both of them when piece is in the correct place. I can use any help especially with the first question. Thank you everyone.
Thanks a lot ! I've changed Update() method with OnMouseDrag() and now I can move all the pieces without any problem. Also, I've swapped the contents of if() and else if() parts, now I can get the particles correctly but there's just one piece always instantiate both of the particles when it is placed correctly. Any idea how can I fix this ?
You're welcome! Seems like OnTriggerStay2D is being called 2 times (with 2 different Collider2D). Try adding Debug.Log("instantiating right particle when colliding with " + other.name) and Debug.Log("instantiating wrong particle when colliding with " + other.name) and, if you still need help, paste here the output.

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Retrieved Text: Save your soul with the power of absorption. You absorb black particles which is good. Destroy red particles by colliding them with the black particles. You grow as you absorb and destroy.
Destroying red particles increases your power meter. Click to use a power bomb to destroy red particles near you. And the only way for a sick score is the power bomb combo. Destroy 2 or more red particles at once using the power bomb to do a combo. The more you do, the more you score. Move with Mouse Power Bomb by clicking when activated.
sORb has been played 3.739 times since it was added on February 3, 2010.
Play the free game sORb and more fun skill games at GamesArca.de, the ultimate source for free online arcade games.

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Retrieved Text: The Physic Material is used to adjust friction and bouncing effects of colliding objects.
See in Glossary in the scene.
Dynamic Friction The friction used when already moving. Usually a value from 0 to 1. A value of zero feels like ice, a value of 1 will make it come to rest very quickly unless a lot of force or gravity pushes the object.
Static Friction The friction used when an object is laying still on a surface. Usually a value from 0 to 1. A value of zero feels like ice, a value of 1 will make it very hard to get the object moving.
Bounciness How bouncy is the surface? A value of 0 will not bounce. A value of 1 will bounce without any loss of energy, certain approximations are to be expected though that might add small amounts of energy to the simulation.
Friction Combine How the friction of two colliding objects is combined.
- Average The two friction values are averaged.
- Minimum The smallest of the two values is used.
- Maximum The largest of the two values is used.
- Multiply The friction values are multiplied with each other.
Friction is the quantity which prevents surfaces from sliding off each other. This value is critical when trying to stack objects. Friction comes in two forms, dynamic and static. Static friction is used when the object is lying still. It will prevent the object from starting to move. If a large enough force is applied to the object it will start moving. At this point Dynamic Friction will come into

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Retrieved Text: So I'm in the middle of creating a waterfall scene which is going to flow down some geometry and collide with a lake. I've set up both the emitters for the waterfall and the wave tank for the lake in separate DOP networks.
However when i try and bring the particles in from the waterfall into the lake DOP the particles don't seem to be having any interaction, the waterfall particles just fall though my static objects even though they should be colliding.
Edit* I've noticed that the bounding box in the flip solver was not including the waterfall particles which fixes the problem of them not moving however the particles still do not interact with the wave tank.

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Retrieved Text: Which more expensive: Broadcast or Conditional?
I'm changing gravity every time something hits a ceiling by the ceiling broadcasting that it's been hit, change the gravity and handling conditionals for needs to change, etc, somewhere else.
Or have you done some magic with arrays/dictionaries between receivers and broadcasters so i can think of these as super fast and light and use lots and lots of braodcasts?
@Deeeds why bother with the broadcast? Why not just have the collide behavior in the object you are broadcasting to?
@iTap-Development It's just an example to make it clear that I'm considering using a LOT of broadcasting, and have already become lazy in relying on it for code organisation.
The question is not about a specific problem: I'm asking the relative cost of using broadcasts versus other approaches to organising and distributing code.
@Deeeds You might want to ask the developers.
I would think that a broadcast/broadcast receive would impact more than a conditional, since broadcast receive behaviours are always waiting for a message to be broadcasted to them.
If you end up getting an answer, let me know too.
Except for my dribbles and rants.
I'm not so sure about the listeners actively listening. This might be just a metaphor being used. They're probably sitting in an array or dictionary that's messaged only when a "broadcast" is sent, meaning highly efficient. Possibly more so than conditionals.
boring story approaching: A friend of mine, a few years ago, spent a huge amount of time teaching me to not use ifs because he'd found them to be a bit of a drag

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Retrieved Text: This Condition can be used every time objects (or more precisely, its colliders) need to collide with each other or with the user himself.
Valid if the specified list of objects are in proximity (it means that the Proximity collider of each object is in collision with each other).
You can specify any object in the scene. If you want to detect when the concerned IO is in proximity with your user, choose Head(IO) (inside the camera) as a colliding object.
OnEnter / OnExit lets you define whether you want the condition to validate when Proximity zones of specified IOs are entering or exiting collision.
If Require All is checked, all the specified objects in this list have to be in proximity with each other. If not checked, as soon as two of them are in proximity, this condition will be validated.
Valid if the specified list of objects are in proximity (it means that the Proximity collider of each object are in collision with each other).
You can specify any object in the scene. If you want to detect when the concerned IO is in proximity with your user, choose Head(IO) (inside the camera) as colliding object.
OnExit: The condition is valid when Proximity zones stop colliding, when they exit from each other’s collider.
If Require All is checked, all the specified objects in this list have to be in proximity with each other. If not checked, as soon as two of them meet the condition it will be validated.

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Retrieved Text: Dark matter is one of the unsolved mysteries in physics and astrophysics.
This hidden matter, which is believed to form as much as 85% of the total matter in the universe, was first introduced about 60 years ago by the astronomer Fritz Zwicky. He developed and later proposed his “missing matter” theory to explain why stars rotating far away from the center of a galaxy move much more quickly than expected, taking account the visible mass of the galaxy.
What Zwicky had called missing matter is now commonly called the dark matter. Dark matter cannot be directly observed by any scientific observation devices, but its existence has been suggested by its gravitational effects.
Weakly Interacting Massive or Low-Mass Particles. They include particles that have a very weak interaction with the rest of the matter, but with a finite mass contributing to the overall mass of the galaxy or universe. Due to their nature, they cannot be “seen” or easily detected and so can be categorized as dark matter. A good candidate is a tiny ghost particle named neutrino that exists in large numbers throughout the universe. Neutrinos are weakly interacting low-mass particles that because of their abundance in the universe can be a good candidate.
Massive Astrophysical Compact Hollow Objects (MACHOS): They include any massive object that can contribute to the dark matter. Black holes, including mini-black holes, that may exist in large numbers in the universe are categorized as MACHO. Contrary to the first candidate, they are very massive and have a high gravitational field. But due to the

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Retrieved Text: It’s the festive time of year once again, and here at helloluxx, we thought we’d share some XP Xmas Advent gifts with all you Cinema 4D users out there. Each day of December until the 24th, we offer you a free X-Particles scene file. It’s going to feel like Christmas everyday!
Well, perhaps not, but we love giving out to the helloluxx community and hopefully this collection of XP scenes will inspire you to create something awesome. I built these files from my library of presets which I’ve been collecting ever since I started using X-Particles. I didn’t necessarily create all these set-ups, they may have been shared online by others. I’m talking about people like Casey Hupke, Mike Batchelor, Mario Tran Phuc, Lothar Mai, Dino Muhic & Joel Dubin. The credit should really go to the amazing collection of artists from around the world who are generous enough to share their knowledge and inspire us all.
If you don’t have X-Particles yet, then you can grab it here, and if you’re looking for more in depth tutorials for X-Particles, then please take a look at learn x-particles 3, which has over seven hours of professional training for working with this powerful particle system.
Let’s start with a slightly festive set-up. This simple scene uses the xpBranch modifier to create one arm of this growing snowflake. The xpTrail object is used to create splines from the particle path and then this is cloned radially using the MoGraph Cloner.
You can create unique snowflakes by changing the xpEmitter Random Seed parameter,

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Retrieved Text: The aurora is caused by charged particles from the sun colliding with molecules and atoms in our atmosphere. The more particles that are expelled by the sun, the more intense the aurora will be. The auroras are concentrated on circles around the magnetic poles, which roughly coincide with the polar circles. This means that the further away from these circles the observer is, the lower on the horizon the aurora will be seen.

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Retrieved Text: This guys rails against Relativity and Quantum Mechanics while being quite entertaining and informative - interesting.
YouTube - Einstein's Idiots 1: What's the point?
Shiloh1... quit posting your own YouTube videos!
Why exactly do QM and Relativity need to be railed against?
If he's going to make up his own explanations for something and then shoot holes in his own made-up explanations, he can disprove just about anything. Those pictures of gold atom collisions, for instance, don't claim to be of the individual protons and neutrons of the initial gold atoms, but of other particles created from the extreme center-of-mass energy of the colliding particles.
Disproving years of experimentally verified physics simply by not understanding it doesn't count for much.
Is that a rhetorical question? Because if you are asking me - I am not the one railing - I just thought his approach was funny and quit entertaining and informative.
Regarding the gold atom collision picture - I think he answers your point begining at 8:10 of the video. They are not traces of particles created by the collision. In the previous video (#7) I think he talks about the elctromagnetic 'ropes' that converge on each atom.
It's not entirely rhetorical, as he's taken the time to make the video, you've taken the time to find and post the video, and then I took the time to watch it. I guess the question for you is "why did you find this challenging?" There are certainly areas of physics that are still being developed and are without lots of experimental evidence, but QM and

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Retrieved Text: 🐺: I was told it was spring. Why is it cold again?
Another great, if not a tad bit chilly, workout today! From long distance, to sprinting, to throwing we had a little bit of everything. Send us a message if your looking to join for a workout!
La temperatura más baja registrada en la Tierra se registró en la Estación Vostok en la Antártida el 21 de julio de 1983.
Y porque amo las montañas.
The Northern Lights are actually the result of collisions between gaseous particles in the Earth's atmosphere with charged particles released from the sun's atmosphere. Variations in colour are due to the type of gas particles that are colliding.
Caption & 📸@foodbysaycheese How many people are Honey Chilly Potato Lovers??
Feeling too warm? Let Nikita Yakushev’s #chilly , “Mountain Manor,” #refresh you! Made using #SpeedTree , #WorldMachine , #SubstancePainter , #SubstanceDesigner , #3dsMax , #ZBrush , #UnrealEngine , and #Photoshop !

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Retrieved Text: This book introduces and reviews both theory and applications of polarizational bremsstrahlung, i.e. the electromagnetic radiation emitted during collisions of charged particles with structured, thus polarizable targets, such as atoms, molecules and clusters.
The subject, following the first experimental evidence a few decades ago, has gained importance through a number of modern applications. Thus, the study of several radiative mechanisms is expected to lead to the design of novel light sources, operating in various parts of the electromagnetic spectrum. Conversely, the analysis of the spectral and angular distribution of the photon emission constitutes a new tool for extracting information on the interaction of the colliding particles, and on their internal structure and dynamical properties.
Last but not least, accurate quantitative descriptions of the photon emission processes determine the radiative energy losses of particles in various media, thereby providing essential information required for e.g. plasma diagnostics as well as astrophysical and medical applications (such as radiation therapy).
This book primarily addresses graduate students and researchers with a background in atomic, molecular, optical or plasma physics, but will also be of benefit to anyone wishing to enter the field.

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Retrieved Text: The “Object Splash” emitter can be found in the “RealWave” shelf. “Object Splash” cannot be used as a stand-alone emitter and requires a RealWave surface.
Here you can choose the objects you want make emit the splash particles. If you need control over the individual splashes then it is recommended to use one emitter per object.
This setting is used to increase the number of created particles. It is closely related to he emitter’s “Resolution” parameter and ranges from 0 to 1. 0 disables the waterline emission, while 1 is used to maximize it.
With this parameter you can control the area around the object where particles will be emitted. A value of 1.0 means that particles will be created in an area of 1 metre around the object.
This is a multiplier to enhance the splash and higher values will produce faster velocities in horizontal direction. You can enter any positive value.
This is a multiplier to enhance the splash and higher values will produce faster velocities in vertical direction. You can enter any positive value.
Higher values are used to create wide-angle particle emissions around the object.
With this parameter you can modify the speed of the particles when they are emitted from the waterline.
With values greater than 0 particles are emitted from polygons below the RealWave surface. This is great for creating particle trails from objects that move underwater. The range is between 0 and 1, where 0 disables the creation of particles.
When “Underwater mult” is active you can enter a positive value. Then, particles are only created between the

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Retrieved Text: From quarks to yet unknown particles, CERN continues to explore new frontiers in physics. Thanks to some of the most complex instruments ever made in a laboratory, Nature can reveal its inner secrets to the scientists.
Mass is the amount of material in an object. Newton showed us that weight is proportional to mass, and Einstein showed that energy is related to mass through the famous equation E = mc2. When it comes to elementary particles, physicists are dealing with a very fundamental question: where does the mass come from?
Why do particles with no known structure have mass?
The answer may lie in the so-called Higgs mechanism. According to this theory, a medium - called the Higgs field - spreads through all the Universe at all times. Particles acquire their mass by interacting with this field, such that those that interact strongly are heavier than those having a weaker interaction. The Higgs boson is the manifestation of the field in the form of a particle. The LHC collision energy is enough to produce such a particle – if it exists.
Antimatter is routinely created in laboratories like CERN and in Nature when cosmic rays hit the atmosphere. Although matter and antimatter must have been produced in the same amounts at the time of the Big Bang, only matter seems to have survived in our Universe today.
Where has all the Big Bang antimatter gone?
The explanation could be differences in the behaviour of matter and antimatter. Tiny experimental differences – the so-called CP violation effects – have already been observed but

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Retrieved Text: Nibbler is an arcade game by Rock-Ola Manufacturing Corporation. Its gameplay is a variant of Pac-Man. The object is to navigate a virtual snake through an enclosed maze, while consuming dots along the way. The length of the snake increases with each object consumed, making the game more difficult. The player must also avoid colliding with walls or obstacles, and must also avoid colliding with the snake's own body sections. After all the objects on the screen have been eaten, the player progresses to the next wave, involving harder obstacles and/or higher game speeds.
As seen on the popular arcade documentary "MAN vs SNAKE: The Long and Twisted Tale of Nibbler"

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Retrieved Text: An international team of astronomers has used a range of telescopes including the Atacama Large Millimeter/submillimeter Array (ALMA) to observe a pair of galaxies colliding at a time when the universe was just half its current age. The project made use of a gravitational magnifying glass created by the gravity of a galaxy between Earth and the subject, and required observations in both visible and infrared light.
The galaxies, known collectively as H-ATLAS J142935.3-002836 (H1429-0028 for short), were originally discovered in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). The system is obscured by a closer galaxy in the foreground, and was found to be extremely faint when viewed in visible light, but appeared much brighter in far-infrared observations.
While the closer, obscuring galaxy created obvious difficulties in directly observing the distant object, the team was able to make use of an effect known as gravitational lensing, wherein a cosmic lens is created by the gravity of a foreground galaxy. This lens deflects the light being emitted from the obscured object, allowing astronomers to study it in detail.
Knowing that this was possible, a campaign of observations were embarked upon, utilising both space and ground telescopes. NASA/ESA’s Hubble Space Telescope and the Keck Observatory were used to reveal the gravitationally-induced ring of light around the obscuring galaxy, helping to gather details about its nature.
The team then used ALMA and the Karl Jansky Very Large Array (JVLA) to study the area at longer wavelengths, penetrating the intervening clouds of dust. Together, these observations revealed that the obscured system was in

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Retrieved Text: One of the first things I wanted to do was to edit an individual mushroom by selecting it, moving it around, transforming it in a number of ways (rotating it, scaling it), etc. Whereas I expected to see each individual mushroom show up in the Outliner tool (which would then allow me to select a mushroom from the Outliner and see it highlighted in the viewport), I only saw a single "Plane" object in the Outliner. Furthermore, I wasn't able to grab individual mushrooms and do anything with them. They all appeared "locked" into the plane and/or greater model at large.
I asked a question on this site and was told that these mushrooms were part of a particle system (which, as a total newbie, I had never heard of before). To make the individual mushrooms editable objects, I needed to go to the Modifiers Panel and click the Convert button. I did this, and sure enough, I am now able to edit each individual mushroom. Thank you Blender SE!
However, I was curious to find out more about particle systems and how they were related to my mushroom patch. I have now watched several video tutorials on Blender particle systems and emitters, and I'm now totally & utterly confused!
How are the individual mushrooms connected to a particle system in the original (on blendswap.com) file? Did the author somehow configure a super customized particle system that "emitted" random mushrooms at random locations?
What does Modifiers >> Convert actually do to a particle system (or anything else)? How did it

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Retrieved Text: Bonus read: Is beaming possible?
Yes, it is, says Johannes Blaschke of the Max Planck Institute for Dynamics and Self-Organization. He briefly explains the basic scientific principles behind beaming and lays out under which circumstances it can be done.
A transporter is a fictional teleportation machine used in the Star Trek universe. Transporters convert a person or object into an energy pattern (a process called de-materialization) and “beam” it to a target – where they are then reconverted into physical matter (re-materialization).
Won’t anything that can be done, eventually be done?
The teleporter ensures that an object (such as a human) disappears from one spot and reappears at another. For example, when Captain Kirk calls his chief engineer, “Beam me up, Scotty,” then disappears from a planet’s surface and reappears in the Enterprise’s transporter room. It’s very hard to say if anything will ever be possible. Instead, I’d like to explain how the Star Trek teleporter works and discuss whether it contradicts any physical principles.
First, I have to describe some basics. Physicists look at the world a bit like a giant game of Lego: every object in the universe is made up of smaller pieces called elementary particles. Surprisingly, only five such elementary particles are needed to build just about anything in the world!
In addition, particles of one variety can be converted into those of another. Energy is either consumed or released. Matter is thus a form of energy. Something is missing in this “world view”, though. For example, if we put together all the Lego bricks for a Lego

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Input Text: Read the passage below and choose the right answer to the following question (choices are the object with many colliding particles has a lower concentration of particles or the object with many colliding particles has a higher concentration of particles ):

At higher concentrations, particles of reactants are crowded closer together, so they are more likely to collide and react.


Ian sees an object with many colliding particles, and he compares it to another object with few colliding particles. Which is true about the objects the object with many colliding particles has a lower concentration of particles or the object with many colliding particles has a higher concentration of particles?

Target Text: the object with many colliding particles has a higher concentration of particles

#### Retrieved Documents ####

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Retrieved Text: I have a problem separating particles colliding with other particles.
Filter demon with "on Collision" option separates only particles hitting/colliding with the object not the other particles.
Any clue how to do it ?
Re: Particle to Particle collision separation - filter/demon script ?

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Retrieved Text: where is my mistake? Particle wont collide with the grid. They should slide or bounce. better both. And why I dont have a preview of my smoke sim?
Last but not least: Where I'm able to find detailed! Tutors with as muach as possible colliding stuff in it. Particles of course.
particles: Add a static solver to your particle dop network with the collision object of your choice. You just have added a collision detect which stores some hit attributes.
smoke: At first glance I think there is something wrong with your dynamic grid. I turned it off and set the bounding box to a proper size and I got some feedback. Maybe start looking there.
Don't even need a static solver, just merge in a ground plane (or other static object) with the right collision relationship on your merge. You can use your own grid I guess but if you want to represent an infinite floor its easier with a ground plane.
could you send me the file please? Dont know some things exactly.
checked it for 3 minutes this morning before work and didn´t save at all.
Do the following: Navigate to the pop network and hit the Ground Plane button in the shelf. Your particles should collide immediately with the ground.
In your autoDop network ( this one with the smoke sim ) just deactivate the auto resize fluid.... node. Resize your fluid Grid a bit. That´s all.

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Retrieved Text: With respect to having objects bounce off one another, I suggest checking out the following links concerning elastic collisions, inelastic collisions, and coefficients of restitution. EDIT: I just noticed that this was covered in another SO question , albeit not specifically for Python.... Is ther a way to know what another object is colliding with? I have a bunch of child objects, each with a trigger collider. I want the parent to be able to know which children are colliding with an object.
Moreover, sprites can be easily created and used to simplify the drawing process and provide a more object-oriented approach to it, and sprite groups provide an efficient way to organize sprites and accomplish tasks such as collision detection. If you are looking to build a simple game in Python or an application with a unique interface, consider using PyGame. how to change wifi password cisco modem dpc2320 So, in this tutorial, I am going to show you how to detect collision between two objects so that you can apply it to your game development project. Here we are going to detect collision with a specific object in Unity 3D with C# programming.
The more complicated problem is how to efficiently detect what objects in a set are overlapping/have collided, without pairwise comparing each object against every other object, which has sub-optimal O(N^2). For this you need a spatial data structure of some kind, like a quad tree. how to draw fur with pastels Collision is knowing when one object has come into contact with another

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Retrieved Text: A particle system is first and foremost driven by attributes. Here are some of the attributes understood by the solvers.
The attributes are listed with the @ style prefix to give the full type. No prefix means float.
There are two suggested methods for creating attributes: POP VOP and POP Wrangle.
In a POP VOP, you can use a Bind Export VOP to write out your desired attribute.
In a POP Wrangle you can use a prototype to specify the attribute and default.
The expression after the equals must be a simple constant expression.
Houdini will use the Cd (diffuse color) point attribute to color particles.
Time in seconds since the particle was born. To get the relative time, useful for fading effects, use @nage.
@age divided by @life. Implicit attribute, you cannot write to this.
Time in seconds the particle is allowed to live. When @age>@life, the particle will be marked dead.
A unique id for the particle that remains the same throughout a single simulation. Always use @id rather than @ptnum to avoid things changing when particles are deleted. Use findattribval() to look up the point number that corresponds with an id.
The particle solver uses the standard v (velocity) attribute as the direction of the particle. Use length(@v) to get the speed of the particle.
Forces on the particle for this frame.
This is multiplied by @pscale to determine the rough shape of the particle for the purpose of rotational inertia.
How much the particle is dragged by any wind effects.
A value from 1 to 2. An exponent of 1 means that a particle is dragged to

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Retrieved Text: The cumulative total of particle hits.
The number of times the particle hit in this detection node.
A path to the object it hit. This is an op: path so it can be used directly by VEX.
The primitive the object hit. Can be -1 if the specific primitive could not be resolved.
The parameteric location on the primitive of the hit. This is not texture uvs. The primuv() VEX function can be used to recover information about the hit location.
The location in space of the collision. Often does not correspond to the current location of the particle as it usually passes through the collision. Also may not correspond to the evaluated location of the hitpath since intra-frame collisions use swept geometry.
The normal of geometry at the time of the collision.
The velocity of the geometry at the time and position of the collision.
When, in seconds, the collision occurred.
You can read the hit attributes directly, or use the POP Collision Behavior node to transform them in some common ways.
This node detects collisions of all particles in the Group field, even if they already collided. So if you're sticking particles, this node will update the hittime of stuck particles at each time step.
To avoid this, you can specify the Group as @stuck=0, so the node only affects particles that aren’t stuck.
In SOP mode, this node only supports collisions with triangles and quads. You can detect collisions with SDFs using the Relationship or DOP Objects and pointing to Static Objects.
This operator modifies the hitnum, hitpath, hitprim, hituv, hitv, hitpos, hitnml, hittime, P, Cd,

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Retrieved Text: [HELP] How to switch the mode of displacement ?
How Can I Make A Platform Lauch My PLayer Into The Air?
How to avoid Character Controller being launched to the air when colliding?
How can I make a flying object follow ground player and stay airborne?
Airplay video play on TV while mirroring is on!
Shaky (jittery) 2D car movement.
How Do I Install Unity 5 on a MacBook Air?
Restrict the particles system, Even when the gameobject is rotating .
Can I use Unity3D in Flash?
Jump in direction while in air?
How to make my vehicle stop from going forward in mid air?

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Retrieved Text: Here, as promised, is episode nine of Mike Paterson’s “Colliding Particles“.
Nothing to do with zombies, although it could have been.
This entry was posted in Particle Physics, Physics, Science and tagged colliding particles, Higgs, video. Bookmark the permalink.

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Retrieved Text: First one needs to know the initial conditions, namely how powerful the collision was: this is done by measuring the remnants of the colliding nuclei in detectors made of high density materials located about 110 meters on both sides of ALICE (the ZDC’s) and by measuring with the FMD, V0 and T0 the number of particles produced in the collision and their spatial distribution. T0 also measures with high precision the time when the event takes place.
An ensemble of cylindrical detectors (from inside out: ITS Pixels (ITS Drift, ITS Strips, TPC, TRD) measures at many points (over 100 just the TPC ) the passage of each particle carrying an electric charge, so that its trajectory is precisely known. The ALICE tracking detectors are embedded in a magnetic field (produced by the huge red magnet !) bending the trajectories of the particles: from the curvature of the tracks one can find their momentum. The ITS is so precise that particles which are generated by the decay of other particles with a very short life time can be identified by seeing that they do not originate from the point where the interaction has taken place (the “vertex” of the event) but rather from a point at a distance of as small as a tenth of a millimeter.
ALICE also wants to know the identity of each particle, whether it is an electron, or a proton, a kaon or a pion. In addition to the information given by ITS and TPC, more specialized detectors are needed: the TOF measures, with

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Retrieved Text: Part 1 – Introduction: Information about what we will be building and what we will not.
Before going into the details, I insist on the fact that the physics system we will build here is not physically correct. We will not resolve collision impact or forces in a realistic way, since this is not the goal here. Instead, our aim is to obtain a simple solution focusing on achieving a good gameplay.
Now that this has been made clear, let’s proceed to the details.
To identify colliders, we will first introduce a new component, the Collider component.
One of the few restrictions we imposed on our game was that all the colliders of objects must have a square shape. Therefore, detecting collisions mostly means detecting intersection between squares.
We will also require a function to check if an object is outside our level to prevent it from going outside of our map area.
Note: You migh wonder why we substract the value 0.5f to coordinates. This is because we assumed that the first tile of our grid was at coordinates (0,0). Therefore, the first tile extends from (-0.5; -0.5) to (0.5;0.5). The same applies to the other borders of our level. Please also note that we assumed each grid cell to be 1-unit wide.
We our now ready to check if an object is colliding another one, or colliding the border of our level.
Before moving an object, our physics sytem will now check if it would result in a colliding position. If so, it will also prevent the colliding object to move.
In the

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Retrieved Text: In ATLAS, the very first component that is reached by colliding particles is the inner detector. As particles collide, their tracks, momentum and charge must be measured with the highest degree of precision. In this interview by ATLAS physicist Steven Goldfarb of colleague Pippa Wells, ATLAS Inner Detector System Project Leader, viewers learn how this measurement is done in the heart of ATLAS. Topics covered include a basic description of the structure of the inner detector, what the detector is trying to do, what types of particles will be able to be seen, how the inner detector records what it sees, what happens to the data collected, the construction and assembly process of the detector, the importance of system testing during assembly, and what would happen if the Higgs particle passed through the detector.

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Retrieved Text: This depiction is, of course, even more utterly balderdashian than all the other boson-pictures combined, because the Higgs is created (and for a short time only) inside the LHC, when other particles collide. While here, one clearly sees two Z-Bosons emotionally colliding, a total figment of imagination.
But I like it anyway, and there's some truth in it, as well, for those to see with their eyes and think in their dreams.

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Retrieved Text: I've also tried with raycasting but none of the pieces moved. I also have one more problem with the OnTriggerStay2D, "else if" part. OnTriggerStay2D should instantiate one of the particles according to puzzle piece is in the correct place or not. But it instantiates both of them when piece is in the correct place. I can use any help especially with the first question. Thank you everyone.
Thanks a lot ! I've changed Update() method with OnMouseDrag() and now I can move all the pieces without any problem. Also, I've swapped the contents of if() and else if() parts, now I can get the particles correctly but there's just one piece always instantiate both of the particles when it is placed correctly. Any idea how can I fix this ?
You're welcome! Seems like OnTriggerStay2D is being called 2 times (with 2 different Collider2D). Try adding Debug.Log("instantiating right particle when colliding with " + other.name) and Debug.Log("instantiating wrong particle when colliding with " + other.name) and, if you still need help, paste here the output.

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Retrieved Text: 🐺: I was told it was spring. Why is it cold again?
Another great, if not a tad bit chilly, workout today! From long distance, to sprinting, to throwing we had a little bit of everything. Send us a message if your looking to join for a workout!
La temperatura más baja registrada en la Tierra se registró en la Estación Vostok en la Antártida el 21 de julio de 1983.
Y porque amo las montañas.
The Northern Lights are actually the result of collisions between gaseous particles in the Earth's atmosphere with charged particles released from the sun's atmosphere. Variations in colour are due to the type of gas particles that are colliding.
Caption & 📸@foodbysaycheese How many people are Honey Chilly Potato Lovers??
Feeling too warm? Let Nikita Yakushev’s #chilly , “Mountain Manor,” #refresh you! Made using #SpeedTree , #WorldMachine , #SubstancePainter , #SubstanceDesigner , #3dsMax , #ZBrush , #UnrealEngine , and #Photoshop !

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Retrieved Text: Dark matter is one of the unsolved mysteries in physics and astrophysics.
This hidden matter, which is believed to form as much as 85% of the total matter in the universe, was first introduced about 60 years ago by the astronomer Fritz Zwicky. He developed and later proposed his “missing matter” theory to explain why stars rotating far away from the center of a galaxy move much more quickly than expected, taking account the visible mass of the galaxy.
What Zwicky had called missing matter is now commonly called the dark matter. Dark matter cannot be directly observed by any scientific observation devices, but its existence has been suggested by its gravitational effects.
Weakly Interacting Massive or Low-Mass Particles. They include particles that have a very weak interaction with the rest of the matter, but with a finite mass contributing to the overall mass of the galaxy or universe. Due to their nature, they cannot be “seen” or easily detected and so can be categorized as dark matter. A good candidate is a tiny ghost particle named neutrino that exists in large numbers throughout the universe. Neutrinos are weakly interacting low-mass particles that because of their abundance in the universe can be a good candidate.
Massive Astrophysical Compact Hollow Objects (MACHOS): They include any massive object that can contribute to the dark matter. Black holes, including mini-black holes, that may exist in large numbers in the universe are categorized as MACHO. Contrary to the first candidate, they are very massive and have a high gravitational field. But due to the

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Retrieved Text: Save your soul with the power of absorption. You absorb black particles which is good. Destroy red particles by colliding them with the black particles. You grow as you absorb and destroy.
Destroying red particles increases your power meter. Click to use a power bomb to destroy red particles near you. And the only way for a sick score is the power bomb combo. Destroy 2 or more red particles at once using the power bomb to do a combo. The more you do, the more you score. Move with Mouse Power Bomb by clicking when activated.
sORb has been played 3.739 times since it was added on February 3, 2010.
Play the free game sORb and more fun skill games at GamesArca.de, the ultimate source for free online arcade games.

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Retrieved Text: The Physic Material is used to adjust friction and bouncing effects of colliding objects.
See in Glossary in the scene.
Dynamic Friction The friction used when already moving. Usually a value from 0 to 1. A value of zero feels like ice, a value of 1 will make it come to rest very quickly unless a lot of force or gravity pushes the object.
Static Friction The friction used when an object is laying still on a surface. Usually a value from 0 to 1. A value of zero feels like ice, a value of 1 will make it very hard to get the object moving.
Bounciness How bouncy is the surface? A value of 0 will not bounce. A value of 1 will bounce without any loss of energy, certain approximations are to be expected though that might add small amounts of energy to the simulation.
Friction Combine How the friction of two colliding objects is combined.
- Average The two friction values are averaged.
- Minimum The smallest of the two values is used.
- Maximum The largest of the two values is used.
- Multiply The friction values are multiplied with each other.
Friction is the quantity which prevents surfaces from sliding off each other. This value is critical when trying to stack objects. Friction comes in two forms, dynamic and static. Static friction is used when the object is lying still. It will prevent the object from starting to move. If a large enough force is applied to the object it will start moving. At this point Dynamic Friction will come into

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Retrieved Text: So I'm in the middle of creating a waterfall scene which is going to flow down some geometry and collide with a lake. I've set up both the emitters for the waterfall and the wave tank for the lake in separate DOP networks.
However when i try and bring the particles in from the waterfall into the lake DOP the particles don't seem to be having any interaction, the waterfall particles just fall though my static objects even though they should be colliding.
Edit* I've noticed that the bounding box in the flip solver was not including the waterfall particles which fixes the problem of them not moving however the particles still do not interact with the wave tank.

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Retrieved Text: This guys rails against Relativity and Quantum Mechanics while being quite entertaining and informative - interesting.
YouTube - Einstein's Idiots 1: What's the point?
Shiloh1... quit posting your own YouTube videos!
Why exactly do QM and Relativity need to be railed against?
If he's going to make up his own explanations for something and then shoot holes in his own made-up explanations, he can disprove just about anything. Those pictures of gold atom collisions, for instance, don't claim to be of the individual protons and neutrons of the initial gold atoms, but of other particles created from the extreme center-of-mass energy of the colliding particles.
Disproving years of experimentally verified physics simply by not understanding it doesn't count for much.
Is that a rhetorical question? Because if you are asking me - I am not the one railing - I just thought his approach was funny and quit entertaining and informative.
Regarding the gold atom collision picture - I think he answers your point begining at 8:10 of the video. They are not traces of particles created by the collision. In the previous video (#7) I think he talks about the elctromagnetic 'ropes' that converge on each atom.
It's not entirely rhetorical, as he's taken the time to make the video, you've taken the time to find and post the video, and then I took the time to watch it. I guess the question for you is "why did you find this challenging?" There are certainly areas of physics that are still being developed and are without lots of experimental evidence, but QM and

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Retrieved Text: This Condition can be used every time objects (or more precisely, its colliders) need to collide with each other or with the user himself.
Valid if the specified list of objects are in proximity (it means that the Proximity collider of each object is in collision with each other).
You can specify any object in the scene. If you want to detect when the concerned IO is in proximity with your user, choose Head(IO) (inside the camera) as a colliding object.
OnEnter / OnExit lets you define whether you want the condition to validate when Proximity zones of specified IOs are entering or exiting collision.
If Require All is checked, all the specified objects in this list have to be in proximity with each other. If not checked, as soon as two of them are in proximity, this condition will be validated.
Valid if the specified list of objects are in proximity (it means that the Proximity collider of each object are in collision with each other).
You can specify any object in the scene. If you want to detect when the concerned IO is in proximity with your user, choose Head(IO) (inside the camera) as colliding object.
OnExit: The condition is valid when Proximity zones stop colliding, when they exit from each other’s collider.
If Require All is checked, all the specified objects in this list have to be in proximity with each other. If not checked, as soon as two of them meet the condition it will be validated.

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Retrieved Text: 1. Clustering and Coarsening in a Granular Gas Granular gases are of great scientific and economic relevance. Scientific, because of their tendency to spontaneously separate into dense and dilute regions, which makes them fundamentally different from any textbook molecular gas. Economic, because no less than 5 per cent of the global energy budget is wasted due to problems with granular matter in conveyor belts, sorting machines, mixers, and other industrial machinery. Here we study - experimentally, numerically, and theoretically - the clustering of particles in a vertically vibrated array of N connected compartments. For strong shaking, the particles spread evenly over the compartments, but if the shaking strength is lowered beneath a critical level this uniform distribution gives way to a clustered state, consisting of a few well-filled compartments and a lot of diluted ones. In the course of time, this state coarsens: The smaller clusters are eaten by the larger ones, until finally only one big cluster remains. This coarsening process is exceptionally slow, with the mass of the surviving cluster growing only as the square root of log t.
In this second lecture we turn to the wonderful world of ratchets, which have become a hot topic in recent years. In order to extract mechanical work on a molecular scale (e.g., to make a muscle move), nature uses the concept of a Brownian ratchet: The stochastic forces from a noisy environment are converted into a directed motion. Here we create a "granular ratchet", exploiting the clustering phenomenon from the previous lecture in a slightly adapted

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Retrieved Text: The aurora is caused by charged particles from the sun colliding with molecules and atoms in our atmosphere. The more particles that are expelled by the sun, the more intense the aurora will be. The auroras are concentrated on circles around the magnetic poles, which roughly coincide with the polar circles. This means that the further away from these circles the observer is, the lower on the horizon the aurora will be seen.

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Retrieved Text: Most objects in space, including stars and planets, are formed by a process called accretion. Accretion occurs when small particles in space attract each other due to gravity, and begin colliding and clumping into larger particles. After a long, long time, enough particles merge together to become the size of a planet or star. When a star forms, its size is determined by how many small particles there are in that particular region of outer space. If there is a lot of material floating around, a large star will eventually be produced. So, stars can form that are bigger than our sun just by having more starting material to build from.

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Retrieved Text: Which more expensive: Broadcast or Conditional?
I'm changing gravity every time something hits a ceiling by the ceiling broadcasting that it's been hit, change the gravity and handling conditionals for needs to change, etc, somewhere else.
Or have you done some magic with arrays/dictionaries between receivers and broadcasters so i can think of these as super fast and light and use lots and lots of braodcasts?
@Deeeds why bother with the broadcast? Why not just have the collide behavior in the object you are broadcasting to?
@iTap-Development It's just an example to make it clear that I'm considering using a LOT of broadcasting, and have already become lazy in relying on it for code organisation.
The question is not about a specific problem: I'm asking the relative cost of using broadcasts versus other approaches to organising and distributing code.
@Deeeds You might want to ask the developers.
I would think that a broadcast/broadcast receive would impact more than a conditional, since broadcast receive behaviours are always waiting for a message to be broadcasted to them.
If you end up getting an answer, let me know too.
Except for my dribbles and rants.
I'm not so sure about the listeners actively listening. This might be just a metaphor being used. They're probably sitting in an array or dictionary that's messaged only when a "broadcast" is sent, meaning highly efficient. Possibly more so than conditionals.
boring story approaching: A friend of mine, a few years ago, spent a huge amount of time teaching me to not use ifs because he'd found them to be a bit of a drag

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Retrieved Text: It’s the festive time of year once again, and here at helloluxx, we thought we’d share some XP Xmas Advent gifts with all you Cinema 4D users out there. Each day of December until the 24th, we offer you a free X-Particles scene file. It’s going to feel like Christmas everyday!
Well, perhaps not, but we love giving out to the helloluxx community and hopefully this collection of XP scenes will inspire you to create something awesome. I built these files from my library of presets which I’ve been collecting ever since I started using X-Particles. I didn’t necessarily create all these set-ups, they may have been shared online by others. I’m talking about people like Casey Hupke, Mike Batchelor, Mario Tran Phuc, Lothar Mai, Dino Muhic & Joel Dubin. The credit should really go to the amazing collection of artists from around the world who are generous enough to share their knowledge and inspire us all.
If you don’t have X-Particles yet, then you can grab it here, and if you’re looking for more in depth tutorials for X-Particles, then please take a look at learn x-particles 3, which has over seven hours of professional training for working with this powerful particle system.
Let’s start with a slightly festive set-up. This simple scene uses the xpBranch modifier to create one arm of this growing snowflake. The xpTrail object is used to create splines from the particle path and then this is cloned radially using the MoGraph Cloner.
You can create unique snowflakes by changing the xpEmitter Random Seed parameter,

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Retrieved Text: Abstract: Definition and measurement of the fundamental units is essential to the principles of physics. Distance has an obvious and simple relationship with the measuring scale. Such a relationship is absent in measuring the mass of an object using the balance scale. This is one of the important factors for the present chaotic scenario in the field of physics.
The concepts of mass and force were deep rooted in the principles of physics. A thought of something wrong with these fundamental concepts is unimaginable. Our whole understanding of physical phenomenon and countless theories are based on these very fundamental concepts. Can these basic concepts stand for scrutiny with simple reasoning?
Mass is defined as the amount of matter inside an object and the matter is defined as the basic particles. Amount by any standard is a count of elements of a particular unit. In the case of mass, it is the count of basic particles inside an object.
It is not sure of how many basic particles were there in the platinum bar approved as the international standard for a kilogram of mass and went onto to compare that standard kilogram of mass with other objects using a balance scale. Here, the balance scale doesn’t compare the number of basic particles inside an object, rather it compares the amount of gravity earth exerts on each the objects. By comparing the objects using the balance scale, we are equating the gravity of the objects with the amount of matter inside those objects.
As it is already evident, a group of same

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Retrieved Text: The “Object Splash” emitter can be found in the “RealWave” shelf. “Object Splash” cannot be used as a stand-alone emitter and requires a RealWave surface.
Here you can choose the objects you want make emit the splash particles. If you need control over the individual splashes then it is recommended to use one emitter per object.
This setting is used to increase the number of created particles. It is closely related to he emitter’s “Resolution” parameter and ranges from 0 to 1. 0 disables the waterline emission, while 1 is used to maximize it.
With this parameter you can control the area around the object where particles will be emitted. A value of 1.0 means that particles will be created in an area of 1 metre around the object.
This is a multiplier to enhance the splash and higher values will produce faster velocities in horizontal direction. You can enter any positive value.
This is a multiplier to enhance the splash and higher values will produce faster velocities in vertical direction. You can enter any positive value.
Higher values are used to create wide-angle particle emissions around the object.
With this parameter you can modify the speed of the particles when they are emitted from the waterline.
With values greater than 0 particles are emitted from polygons below the RealWave surface. This is great for creating particle trails from objects that move underwater. The range is between 0 and 1, where 0 disables the creation of particles.
When “Underwater mult” is active you can enter a positive value. Then, particles are only created between the

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Retrieved Text: Nibbler is an arcade game by Rock-Ola Manufacturing Corporation. Its gameplay is a variant of Pac-Man. The object is to navigate a virtual snake through an enclosed maze, while consuming dots along the way. The length of the snake increases with each object consumed, making the game more difficult. The player must also avoid colliding with walls or obstacles, and must also avoid colliding with the snake's own body sections. After all the objects on the screen have been eaten, the player progresses to the next wave, involving harder obstacles and/or higher game speeds.
As seen on the popular arcade documentary "MAN vs SNAKE: The Long and Twisted Tale of Nibbler"

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Retrieved Text: An international team of astronomers has used a range of telescopes including the Atacama Large Millimeter/submillimeter Array (ALMA) to observe a pair of galaxies colliding at a time when the universe was just half its current age. The project made use of a gravitational magnifying glass created by the gravity of a galaxy between Earth and the subject, and required observations in both visible and infrared light.
The galaxies, known collectively as H-ATLAS J142935.3-002836 (H1429-0028 for short), were originally discovered in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). The system is obscured by a closer galaxy in the foreground, and was found to be extremely faint when viewed in visible light, but appeared much brighter in far-infrared observations.
While the closer, obscuring galaxy created obvious difficulties in directly observing the distant object, the team was able to make use of an effect known as gravitational lensing, wherein a cosmic lens is created by the gravity of a foreground galaxy. This lens deflects the light being emitted from the obscured object, allowing astronomers to study it in detail.
Knowing that this was possible, a campaign of observations were embarked upon, utilising both space and ground telescopes. NASA/ESA’s Hubble Space Telescope and the Keck Observatory were used to reveal the gravitationally-induced ring of light around the obscuring galaxy, helping to gather details about its nature.
The team then used ALMA and the Karl Jansky Very Large Array (JVLA) to study the area at longer wavelengths, penetrating the intervening clouds of dust. Together, these observations revealed that the obscured system was in

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Retrieved Text: Bonus read: Is beaming possible?
Yes, it is, says Johannes Blaschke of the Max Planck Institute for Dynamics and Self-Organization. He briefly explains the basic scientific principles behind beaming and lays out under which circumstances it can be done.
A transporter is a fictional teleportation machine used in the Star Trek universe. Transporters convert a person or object into an energy pattern (a process called de-materialization) and “beam” it to a target – where they are then reconverted into physical matter (re-materialization).
Won’t anything that can be done, eventually be done?
The teleporter ensures that an object (such as a human) disappears from one spot and reappears at another. For example, when Captain Kirk calls his chief engineer, “Beam me up, Scotty,” then disappears from a planet’s surface and reappears in the Enterprise’s transporter room. It’s very hard to say if anything will ever be possible. Instead, I’d like to explain how the Star Trek teleporter works and discuss whether it contradicts any physical principles.
First, I have to describe some basics. Physicists look at the world a bit like a giant game of Lego: every object in the universe is made up of smaller pieces called elementary particles. Surprisingly, only five such elementary particles are needed to build just about anything in the world!
In addition, particles of one variety can be converted into those of another. Energy is either consumed or released. Matter is thus a form of energy. Something is missing in this “world view”, though. For example, if we put together all the Lego bricks for a Lego

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Retrieved Text: What physics framework are you using? box2d? cocos2d physics?
Anyway i don’t understand your question, if i see your image, everything are colliding with everything.
The object that contains the balls (we can call it as “tumbler”), are colliding with the balls. I’m imagining the tumbler as a custom shape with N vertices.
set bitmasks if you haven’t so already and return false.

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======= Instance Index 27 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are far from or close to ):

In bigger atoms, valence electrons are farther from the nucleus.


Charles sees an atom through the microscope that is the smallest he's ever seen. The valence electrons in this atom are likely far from or close to the nucleus?

Target Text: close to

#### Retrieved Documents ####

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Retrieved Text: – An element is defined as a substance which cannot be decomposed into other substances. The smallest particle of an element which takes part in chemical reaction is known as atom.
– All matter is composed of atoms which are infinitesimally small.
from the stand point of electrical conductivity, as conductors, semiconductors or Insulators .To be conductor, the substance must contain some mobile electrons that can move freely between atoms. These free electrons come only from the valence (outer) orbit of the atom Conductivity depends on the number of electrons in the valence orbit.
“The energy level of an electron increases as its distance from the nucleus increases. Thus an electron in the second orbit possesses more energy than electron in the first orbit, electrons in the third orbit have higher energy than in the second orbit and so on. It follows, therefore, that electrons in the last orbit will possess very high energy. These high energy electrons are less bound to the nucleus and hence they are more mobile. It is the mobility of last orbit electrons that they acquire the property of combining with other atoms. Further due to this combining power of last orbit electrons of an atom they are called valence electrons”.
Atoms with fewer than four valence electrons are good conductors.
Atoms with more than four valence electrons are poor conductors.
Atoms with four valence electrons are semiconductors.
Normally, the atoms are electrically neutral, that is, the number of electrons and protons are the same, cancelling each other’s electrical force. Atoms “stay together’ because unlike charges attract each

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Retrieved Text: As a homeschooling mom, I think hands on activities make learning science so much more interesting and fun. I also think they help children to understand science in a more concrete way. Things like atoms and molecules are pretty hard for a young child to comprehend without something tangible to relate to. In this post, and in a series of posts that will follow, I want to share with you some ideas for teaching elementary and middle school aged children about chemistry.
Let’s start with atoms and molecules.
Atoms are tiny tiny particles that make up all matter. You can’t see them - in fact, they are so tiny that millions and millions of them can fit in the point of the very sharpest pencil. But eveything around us is made of millions and millions of atoms - our bodies, our homes, our pets, the trees, even the air we breathe! To help make this concept more concrete, take a look through a magnifying glass at an image in a book or a picture printed from your computer. This will work best with a magnifying glass that magnifies at 4X or higher.
What do you see? Can you see that the picture is made from many many tiny dots? When you look at the picture with just your eyes, you don’t see the dots, but the picture is really just a whole lot of tiny dots of color put together. Atoms are like this - only even smaller!
This is a fun activity for a group of children. You build

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Retrieved Text: An atom is the smallest particle of matter that can combine chemically with another atom or molecule. It has a nucleus, composed of protons and neutrons, around which electrons orbit.
The electron carries a charge equal to the proton but opposite in charge (-e).
An atom has as many protons as electrons. The total charge is zero which is why matter is usually neutral.
In some cases, with the help of an external energy input, an atom can lose or gain one or more electrons. This is the phenomenon of ionization.
Example: An atom of sodium (Na) has 11 protons and 11 electrons. If it loses an electron, it then has 11 protons but only 10 electrons. A positive charge +e is no longer balanced and the resulting sodium ion is positively charged. The sodium ion, Na+, indicates that it carries a charge +e.
A molecule is an assembly of atoms that share electrons to achieve greater stability.
Click on one of the four active zones to start the animation.
To know the structure of an atom and a molecule.
To define an electrical charge.
To understand the phenomenon of the ionization of an atom.
To know the difference between a valence electron and a free electron.
To recognize two types of atomic bonds.

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Retrieved Text: Semiconductors are utilized widely in electric circuits. As its name signifies, a semiconductor is a component which carries out electric power, but only partially. The conductivity of a semiconductor is someplace in between that of an insulator, that has basically no conductivity, and a conductor, that has basically complete conductivity. Many semiconductors are crystals made from specific components, many generally silicon.
To comprehend how semiconductors function, you should initially comprehend a little about how electrons are arranged in an atom. The electrons in an atom are arranged in layers. These layers are known as shells. The outer shell is known as the valence shell.
The electrons within this shell are the ones which form bonds with surrounding atoms. This type of bonds are known covalent bonds. Many conductors have only one electron in the valence shell. Semiconductors, however, generally have 4 electrons in their valence shell.
it is feasible for all the valence electrons to connect with valence electrons coming from other atoms if all the surrounding atoms are of the exact same type. The atoms organize on their own into structures known crystals while that occurs. Semiconductors are produced of such crystals, generally silicon crystals.
Right here, each circle stands for a silicon atom, and the lines in between the atoms stand for the shared electrons. Each of the 4 valence electrons in each silicon atom is provided one surrounding silicon atom. Hence, every silicon atom is bound with 4 other silicon atoms.
Pure silicon crystals aren’t all that effective digitally. If you present little quantities of other elements into

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Retrieved Text: As seen in the previous section on the octet rule, atoms tend to lose or gain electrons in order to attain a full valence shell and the stability a full valence shell imparts. Because electrons are negatively charged, an atom becomes positively or negatively charged as it loses or gains an electron, respectively. Any atom or group of atoms with a net charge (whether positive or negative) is called an ion. A positively charged ion is a cation while a negatively charged ion is an anion. In this section, we briefly look at some of the processes through which electrons are gained and lost in the formation of ions.
The process of gaining or losing an electron requires energy. There are two common ways to measure this energy change: ionization energy and electron affinity.
The ionization energy is the energy it takes to fully remove an electron from the atom. Ionization energy is a property that varies predictably across the periodic table. Group I and II elements with few electrons in their outer shell have very low ionization energies, while ionization energies increase dramatically moving right along the periodic table. The octet rule gives a straightforward (albeit simplified) explanation of this trend: elements with few valence electrons (those on the left of the periodic table) readily give them up in order to attain a full octet within their inner shells.
When several electrons are removed from an atom, the energy that it takes to remove the first electron is called the first ionization energy, the energy it takes to

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Retrieved Text: Not all atoms within a neutral molecule need be neutral. An atom can have the following charges: positive, negative, or neutral, depending on the electron distribution. This is often useful for understanding or predicting reactivity. Identifying formal charges helps you keep track of the electrons.
Determining the appropriate number of valence electrons for an atom – This can be accomplished by inspecting the periodic table. The group number indicates the appropriate number of valence electrons for each atom.
Determining whether the atom exhibits the appropriate number of electrons – In the Lewis structure, determine whether some of the atoms show an unexpected number of electrons.
The formal charge on an atom can be calculated using the following mathematical equation.
Lewis structures also show how atoms in the molecule are bonded. They can be drawn as lines (bonds) or dots (electrons). One line corresponds to two electrons. The nonbonding electrons, on the other hand, are the unshared electrons and these are shown as dots. One dot is equal to one nonbonding electron. The valence electrons are the electrons in the outermost shell of the atom.
[Formal charge]H = 1 – (1/2) × 2 – 0 = 0 ⇒ This applies to each hydrogen. These hydrogens are all zero.
⇒ This molecule is neutral.
[Formal charge]c = 4 – (1/2) × 6 – 0 = 4 – 3 – 0 = +1 ⇒ This is a cation.
[Formal charge]c = 4 – (1/2) × 6 – 2 = 4 – 3 – 2 = -1 ⇒ This is a anion.

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Retrieved Text: Electron dot structures, also called Lewis structures, are a graphical representation of the way electrons are distributed throughout a compound. Each element's chemical symbol is surrounded by lines, representing bonds, and dots, representing non-bonded electrons. When drawing an electron structure, your goal is to make each element's valence, or outer electron shell, as full as possible, without going over the maximum number of electrons for that shell.
Determine each element in the structure by looking at its chemical formula. For example, carbon dioxide's formula is CO2. Therefore it has one carbon atom and two oxygen atoms.
Look up each element on the Periodic Table. Note each group, or column number. This reflects how many valence electrons the element has. For instance, carbon is in group 4A and oxygen is in group 6A; therefore carbon has four valence electrons and oxygen has six.
Add the valence electrons of all the elements. This is the total number of electrons available for the dot structure. Since 4 + 6 + 6 = 16, there will be 16 electrons in carbon dioxide's Lewis structure.
Determine which element is the least electronegative, or has the weakest pull on the electrons, by looking on an electronegativity chart or by examining the element's position relative to the other elements on the Periodic Table. Elements generally increase in electronegativity from left to right and from bottom to top. Carbon is the least electronegative element in the compound, with a value of 2.5.
Place the least electronegative element in the center of the structure, then surround it with the other

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Retrieved Text: Pure semiconductors are relatively good insulators as compared with metals, though not nearly as good as a true insulator like glass. To be useful in semiconductor applications, the intrinsic semiconductor, pure undoped semiconductor must have no more than one impurity atom in 10 billion semiconductor atoms. This is analogous to a grain of salt impurity in a railroad boxcar of sugar. Impure, or dirty semiconductors are considerably more conductive, though not as good as metals. Why might this be? To answer that question, we must look at the electron structure of such materials in Figure below.
The crystal lattice in Figure below (a) contains atoms having four electrons in the outer shell, forming four covalent bonds to adjacent atoms. This is the anticipated crystal lattice. The addition of a phosphorus atom with five electrons in the outer shell introduces an extra electron into the lattice as compared with the silicon atom. The pentavalent impurity forms four covalent bonds to four silicon atoms with four of the five electrons, fitting into the lattice with one electron left over. Note that this spare electron is not strongly bonded to the lattice as the electrons of normal Si atoms are. It is free to move about the crystal lattice, not being bound to the Phosphorus lattice site. Since we have doped at one part phosphorus in 10 million silicon atoms, few free electrons were created compared with the numerous silicon atoms. However, many electrons were created compared with the fewer electron-hole pairs in intrinsic silicon. Application of an external electric

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Retrieved Text: The Lewis Structure or the Lewis Dot Structure is a method of representing molecules where the individual atoms are represented by their periodic symbol (H for Hydrogen, C for Carbon etc.) around which the number of valence electrons for that atom is drawn.
The Lewis structure is an easy way to interpret the number of bonds an atom will form, its lone pair electrons, and predicting the number of electrons it will need/give up to conform to the octet rule. For Example, in drawing the lewis dot structure for Carbon we draw 4 valence electrons around it and thus know that it will need 4 more electrons to conform to the octet rule i.e. in the case of carbon, 8 electrons in its outermost shell. An easy way to remember the number of valence electrons of an atom is by following the periodic table where each group represents a particular valency number.
A few rules while making the Lewis Dot Structure for a compound involves first, drawing the dot structure for an atom, second, connecting the atoms with more than one bond, third, connecting the atoms with one bond and finally checking if each atom follows the octet rule.

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Retrieved Text: Electron dot diagrams, sometimes called Lewis dot diagrams, were first used by Gilbert N. Lewis in 1916. These diagrams are used as a shorthand notation to show the number of valence electrons in an atom. More complicated versions can be used to show the bond between different atoms in a molecule.
Write the symbol of the atom you are drawing the electron dot diagram for in the middle of your paper. This symbol represents the nucleus of the atom and each of the four sides represents an orbital.
Locate the element you are drawing an electron dot diagram for on the periodic table of elements. Find the number of electrons in one atom of the element. The number of electrons is the same as the element's atomic number.
Find the number of valence electrons by subtracting the number of electrons in each level from the total number of electrons. There are two electrons in the first level and eight in the second, third and fourth levels. The diagram will represent only the outermost level of the electron field. Take the number of electrons and subtract the number of electrons in each level until you come to a level that is not entirely full. For the noble gases, the last level will be full, with no electrons left over, and this is the level you will draw.
Place the first two dots on the right side of the element symbol. This side is referred to as the s orbital.
Place the remaining dots in a counterclockwise fashion around the edges of the

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Retrieved Text: Atom is the smallest building block of an element – it can’t be further broken by any chemical process. Everything you see around yourself is made of trillions-of-trillions atoms.
Atoms are so small that, it is not possible to see them with a powerful microscope. Only specialized microscopes (electron microscope) are able to zoom the atoms.
An atom is composed of electrons, protons, and neutrons. Neutrons and protons are held together in the center of an atom called nucleus. But, electrons orbit around atoms at fixed distances called orbits or shells. A neutral atom (without charge) contains an equal number of electrons and protons.
The total mass of the atom is concentrated in its nucleus, which is measured in a.m.u (atomic mass unit). One a.m.u is about kilogram. Mass of the atom is equal to the number of nucleons (sum of the number of protons and neutrons). One nucleon – either a proton or a neutron – has a mass equal to 1 a.m.u.
Elements are distinguished from each other by the number of protons. If somehow number of protons is changed in an element – as it happens during radioactivity – then the original element will be converted into another element. However, changing the number of neutrons doesn’t change the element itself. Instead, it will give a different isotope of the same element. An isotope of an element has the same number of protons but a different number of neutrons.
There 118 different kinds of atoms based on the number of protons, that builds 118 different elements. These elements are

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Retrieved Text: We know from the periodic table Carbon atoms have 4 valence electrons on the outer shells.
According to the Octet Rule of Electron Configuration, this means the four are free to wonder and find opportunity to PAIR UP with other atoms.
That’s because The Octet Rule requires the valence shell or outermost shell of the atoms to have 8 electrons to become stable.
When two carbon atoms come together, they can each share 1 electron and form a single bond. That will leave three valence electrons from each atom to pair up with other electrons from other atoms they come in contact with.
The skeletal structure shows the type of bonding between elements.
Here’s a trick – if you draw a line through the middle of the carbon bonds, you should be able to work out exactly 4 bonds on each side, because each carbon atom has 4 bonding electrons which are the valence electrons.

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Retrieved Text: This is “Multiple Covalent Bonds”, section 4.3 from the book Introduction to Chemistry: General, Organic, and Biological (v. 1.0). For details on it (including licensing), click here.
Recognize molecules that are likely to have multiple covalent bonds.
This does not give the carbon atom a complete octet; you will find only six electrons in its valence shell. In addition, each oxygen atom has only seven electrons in its valence shell. Finally, no atom makes the number of bonds it typically forms (Figure 4.2 "How Many Covalent Bonds Are Formed?"). This arrangement of shared electrons is far from satisfactory.

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Retrieved Text: · Instead of gaining and loosing electrons, carbon shares its 4-electrons with another element or carbon to form molecule.
· Covalent bonds are formed as a result of sharing of electrons. Example- H2, O2, N2. Covalent compounds have low melting point and boiling point due to small intermolecular forces.
· H2forms by sharing valence electrons (1 per atom of H) and produce single bond between two hydrogen atoms.
· O2 forms by sharing valence electrons (2 per atom of O) and produce double bond between two oxygen atoms.
· N2forms by sharing valence electrons (3 per atom of N) and produce triple bond between two nitrogen atoms.
· Methane, CH4is simple carbon compounds and used as a fuel on large scale and also a major component of CNG (Compressed Natural Gas). Methane formed due to sharing of 4 valence electrons of carbon with 4 hydrogen atoms.
Carbon have three allotropes i.e. Diamond, Graphite and fullerene.
Diamond formed due to rigid three dimensional structures of carbon atoms because each carbon atom bonded to another 4 carbon atoms. It is hardest substance.
Graphite formed due to presence of hexagonal array layers above one another, and layers of hexagonal arrays formed because each carbon atom bonded to another 3 carbon atoms with 2 single and 1 double bond. It is smooth, slippery and very good conductor of electricity.
Fullerenes (C-60) are also an allotrope of carbon in which carbon atoms are arranged in football like shape.
Carbon shows versatile nature because it has two characteristics features which are catenation and tetravalency. These both feature gives large numbers of compounds.
Catenation

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Retrieved Text: Thinking in terms of overlapping atomic orbitals is one way for us to explain how chemical bonds form in diatomic molecules. However, to understand how molecules with more than two atoms form stable bonds, we require a more detailed model. As an example, let us consider the water molecule, in which we have one oxygen atom bonding to two hydrogen atoms. Oxygen has the electron configuration 1s22s22p4, with two unpaired electrons (one in each of the two 2p orbitals). Valence bond theory would predict that the two O–H bonds form from the overlap of these two 2p orbitals with the 1s orbitals of the hydrogen atoms. If this were the case, the bond angle would be 90°, as shown in [link], because p orbitals are perpendicular to each other. Experimental evidence shows that the bond angle is 104.5°, not 90°. The prediction of the valence bond theory model does not match the real-world observations of a water molecule; a different model is needed.
Quantum-mechanical calculations suggest why the observed bond angles in H2O differ from those predicted by the overlap of the 1s orbital of the hydrogen atoms with the 2p orbitals of the oxygen atom. The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically

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Retrieved Text: knowledge. To understand the ... To understand these claims, one needs a knowledge of chemistry. .... This film, produced by Open University/BBC-TV, is the.
that there have been too many pet "periodic charts" published in recent years, including the same chart by the same author in this JOURNAL in 1939. Another.
a. Using the data in the table above, is the periodic table is organized by increasing atomic mass? Explain. No. There are several places on the periodic table where the mass does not increase with the atomic number, in the data table above this can be shown between Argon (Ar) and Potassium (K) and again between Tellurium (Te) and Iodine (I). b. What property is the periodic table organized by? Increasing Atomic number (protons). *In the top right hand corner of your screen check (√) the box next to “Electrons.” This will make the electron count for each element appear to the right of its symbol in the periodic table. 19. What electron pattern do you notice for all of the elements belonging to the Alkali Metal family? The last electron listed (valence electron) is 1. 20. Considering your answer above, though we know Hydrogen is a non-metal, why do you think it is placed on top of the alkali metals? It’s number of valence electrons is the same as the members of the Alkali Metal family. 21. What electron pattern can be observed with the Noble Gases? The Halogens? Noble Gases all have 8 valence electrons, except He which has 2. Halogens family members each have

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Retrieved Text: describe the three-dimensional nature of molecules.
sketch a tetrahedral molecule, CX4, using the “wedge-and-broken-line” method of representation.
make a ball-and-stick model of a simple tetrahedral molecule such as methane, CH4.
When drawing any organic structure, you must remember that a neutral carbon atom will almost always have four bonds. Similarly, hydrogen always has one bond; neutral oxygen atoms have two bonds; and neutral nitrogen atoms have three bonds. By committing these simple rules to memory, you can avoid making unnecessary mistakes later in the course.
The “wedge-and-broken-line” type of representation, which helps to convey the three-dimensional nature of organic compounds, will be used throughout the course.
Metallic bonds These bonds are found in solid metals (copper, iron, aluminum) with each metal bonded to several neighboring groups and bonding electrons free to move throughout the 3-dimensional structure.
Each bond classification is discussed in detail in subsequent sections of the chapter. Let's look at the preferred arrangements of electrons in atoms when they form chemical compounds.
Figure 1.4.1: G. N. Lewis and the Octet Rule. (a) Lewis is working in the laboratory. (b) In Lewis’s original sketch for the octet rule, he initially placed the electrons at the corners of a cube rather than placing them as we do now.
At the beginning of the 20th century, the American chemist G. N. Lewis (1875–1946) devised a system of symbols—now called Lewis electron dot symbols, often shortened to Lewis dot symbols—that can be used for predicting the number of bonds formed by most elements in their compounds. Each Lewis dot symbol consists of the chemical symbol for

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Retrieved Text: (e) H2CO (Formaldehyde) (f) C6H6 (Benzene).
3. What valence atomic orbitals formed the bonds of the compounds listed in problem (2)?
4. What compound listed in problem (2) has Pi (π) bonds that cannot be entirely described as localized Pi (π) bonds?
5. Write the general representative strings for Sigma (σ) bonds and Pi (π) bonds.
1(a) Resonance structures (also called resonance forms): the different Lewis structures that are equally acceptable descriptions of a single molecule.
(b) Sigma (σ) bond: a covalent bond in which the electron density is concentrated symmetrically about the line joining the nuclei (internuclear axis) of the bonded atoms. In other words, a covalent bond in which the internuclear axis passes through the middle of the region of orbital overlap (figure 9.16).
Pi (π) bond: a covalent bond in which the electron density is concentrated above and below the internuclear axis of the bonded atoms. In other words, a covalent bond in which the line passing through the middle of the region of orbital overlap is perpendicular to the internuclear axis of the bonded atoms (figure 9.17).
Localized electrons: σ and π electrons totally associated with the atoms that form the bond. Such bonds are localized bonds.
Delocalized electrons: electrons not totally associated with the atoms that form the bond. Such bonds are delocalized bonds. Delocalized bonds are commomly encountered in molecules that have two or more resonance structures involving π bonds. Such bonds are called delocalzed π bonds.
2(a) The valence-shell configuration of H = 1s1. Two s orbitals overlap to form H2. The internuclear axis of the atoms passes

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Retrieved Text: The inert or noble gases have a stable full outer shell of electrons which is why they are so unreactive. Which group of elements has a stable number electrons in the outer energy level. Periodic table of the elements. How many valence electrons are in an atom of chlorine.
R Another exception -- the transition metals. The elements are arranged by increasing order of atomic number. Elements whose atoms have the same number of electrons in outer energy levels are in the same family. Their arrangement is characterized by different energy levels and orbitals within these levels. How to Find the Maximum Number of Electrons That Can Occupy a Shell.
How does the number of electrons in outer energy levels to the position of an element in the periodic table. An exception to this rule is He Helium. How do valence electrons determine chemical properties. How many valence electrons are in a silicon atom. You can check these answers with the simple method if you like, but it does work out in any case.

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Retrieved Text: To find valence electrons using a period table, first see if your atom is a transitional metal, which are the elements in the middle rectangle of the table. If the atom is outside this block, locate its group number along the top of the table. The ones digit in the group number is the number of valence electrons. To solve without a periodic table, find the electron configuration of the element and count the electrons into 1 group of 2, and then into shells of 8. The number in the last group is the amount of valence electrons.

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Retrieved Text: 12. the tendency of an atom in a molecule to attract shared electrons to itself.
13. an electron pair that is localized on a given atom, an electron pair not involved in bonding.
14. a condition occurring when more than one valid Lewis structure can be written for a particular molecule.
16. the charge assigned to an atom in a molecule or polyatomic ion derived from a specific set of rules.
20. the energy required to break a given chemical bond.
22. a type of bond in which electrons are shared by atoms.
1. the energy change occurring when separated gaseous ions are packed together to form an ionic solid.
2. a property of a molecule whose charge distribution can be represented by a center of positive charge and a center of negative charge.
6. a diagram of a molecule showing how the valence electrons are arranged among the atoms in the molecule.
8. a model which assumes that a molecule is composed of atoms that are bound together by sharing pairs of electrons using the atomic orbitals of the bound atoms.
10. a model whose main postulate is that the structure around a given model atom in a molecule is determined principally by minimizing electron-pair repulsions.
11. a covalent bond in which the electrons are not shared equally because one atom attracts them more strongly than the other.
17. the observation that atoms of nonmetals tend to form the most stable molecules when they are surrounded by eight electrons (to fill their valence orbitals).
19. an electron pair found in the space between two atoms.

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Retrieved Text: A covalent bond is formed between two non-metals that have similar electronegativities. Neither atom is "strong" enough to attract electrons from the other. For stabilization, they share their electrons from outer molecular orbit with others. An ionic bond is formed between a metal and a non-metal. Non-metals(-ve ion) are "stronger" than the metal(+ve ion) and can get electrons very easily from the metal. These two opposite ions attract each other and form the ionic bond.
Covalent bonding is a form of chemical bonding between two non metallic atoms which is characterized by the sharing of pairs of electrons between atoms and other covalent bonds. Ionic bond, also known as electrovalent bond is a type of bond formed from the electrostatic attraction between oppositely charged ions in a chemical compound. These kinds of bonds occur mainly between a metallic and a non metallic atom.
The covalent bond is formed when two atoms are able to share electrons whereas the ionic bond is formed when the "sharing" is so unequal that an electron from atom A is completely lost to atom B, resulting in a pair of ions.
Each atom consists of protons, neutrons and electrons. At the centre of the atom, neutrons and protons stay together. But electrons revolve in orbit around the center. Each of these molecular orbits can have a certain number of electrons to form a stable atom. But apart from Inert gas, this configuration is not present with most of the atoms. So to stabilize the atom, each atom shares half of its electrons.
Covalent bonding is

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Retrieved Text: the smallest unit of an element that has all of the properties of the element; basic building block of matter.
the number of protons and neutrons in the nucleus of one atom of the element.
the number of protons contained in each nucleus of its atoms of the element.
a horizontal row (left to right) in the periodic table.
a vertical column (up and down) on the periodic table.
a chart that organizes information about all of the known elements according to their atomic number.
describes how likely an element is to form bonds with other elements.
group 1 metals on the periodic table that contain 1 valence electron and lose their valence electrons the most easily, making them the most reactive metals.
group 1 metals on the periodic table that contain 2 valence electrons and are the second most reactive metals.
group 3-­12 on the periodic table. They have varying valence electrons and do not follow the normal trends of the other metals. They form brightly colored compounds and ions in solution.
group 17 nonmetals on the periodic table that contain 7 valence electrons. They only need to gain 1 valence electron to have a stable octet. They gain valence electrons the most readily, making them the most reactive nonmetals.
group 18 elements on the periodic table that contain 8 valence electrons (He has 2) and a full valence shell making them very stable and inert.
an element that has some properties of a metal and some properties of a nonmetal. The metalloids are found on the boron staircase, there are 7 metalloids: B, Si, Ge, As,

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Retrieved Text: Atoms gain or lose electrons in order to achieve a noble gas configuration (an octet). The formula for the ionic compound zinc chloride is ##"ZnCl"_2##. When forming an ion, a zinc atom loses its two valence electrons, becoming a ##"Zn"^"2+"## ion. The chlorine atom has seven valence electrons, and will gain one valence electron to form a chloride ion, ##"Cl"^"1-"##. Ionic compounds are neutral, which means that the sum of the positive charges and the negative charges must equal zero. Therefore, two chloride ions, ##"Cl"^"1-"## must bond with one zinc ion, ##"Zn"^"2+"##. The sum of the positive two charge on the zinc and the negative one charge on the two chloride ions equals zero. The ionic bond is formed by the electrostatic attraction between the oppositely charged ions.

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Retrieved Text: 3. Type of waves that pass through soft body tissues but stopped by bones.
5. Type of waves that cause sunburn.
6. Part of the spectrum our eyes are sensitive to.
8. The space around the nucleus of an atom where electrons are found.
9. Neutral particle found in the nucleus of an atom.
12. Number of protons in an atom's nucleus.
13. Forms of the same element with different numbers of neutrons.
14. The sum of protons and neutrons in an atom.
15. Last name of chemisty who gave us the law of definite proportions.
16. Greek philosopher who first coined the idea of the atom.
20. A way of illustrating valence electrons.
22. Last name of scientists who discovered electrons.
23. A testable prediction to explain an observation.
24. Last name of chemisty who gave us the law of conservation of matter.
25. Type of electrons in the outermost energy level of an atom.
26. Waves with the lowest frequencies of the spectrum.
1. Regions of space in which electrons can move about the nucleus.
2. The four basic elements of matter according to the ancient Greeks [no spaces between words].
4. A fact of nature that is observed so often it is accepted as truth.
7. Type of waves that travel at the speed of light through space.
10. Small, dense, positively charged central core of an atom.
11. Positively charged subatomic particle.
17. Last name of scientist who discovered the nucleus.
18. An explanation based on many tests.
19. Type of waves with highest frequency and shortest wavelength.
21. Type of wave energy given off by the human body and other warm objects.

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Retrieved Text: Periodic table[ edit ] Electron configuration table The form of the periodic table is closely related to the electron configuration of the atoms of the elements. Phosphorus, for instance, is in the third period.
Pauli-Exclusion Principle Wolfgang Pauli postulated that each electron can be described with a unique set of four quantum numbers. The electron configuration can be visualized as the core electronsequivalent to the noble gas of the preceding periodand the valence electrons: It is possible to predict most of the exceptions by Hartree—Fock calculations,  which are an approximate method for taking account of the effect of the other electrons on orbital energies.
Nitrogen, for example, has 3 electrons occupying the 2p orbital.
In bulk materials, this idea helps explain the peculiar properties of lasers and semiconductors. That is, we follow the three important rules: For atoms, the notation consists of a sequence of atomic subshell labels e.
It may be stated as: However, the energy of an electron "in" an atomic orbital depends on the energies of all the other electrons of the atom or ion, or molecule, etc. Hund's Rule Hund's Rule states that when electrons occupy degenerate orbitals i.
The electronic configuration for Cl- can, therefore, be designated as 1s22s22p63s23p6. The fact that the Aufbau principle is based on an approximation can be seen from the fact that there Atom and electron configuration an almost-fixed filling order at all, that, within a given shell, the s-orbital is always filled before the p-orbitals.
If that were the case, the 3d-orbital would have the same energy as the 3p-orbital,

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Retrieved Text: Number of protons present in nucleus of atom of an element is known as atomic number.
Mass number is also known as atomic mass. Atomic number or mass number is equal to number of protons and neutrons in atom.
Atoms of same elements which have same atomic number but different mass number is called isotopes.
example : Protium, Deutrium, Tritium are isotopes of hydrogen.
Atoms of different elements which have similar atomic mass and different atomic number are called isobars.
In 1921, Bohr and Bury gives some laws for distribution of electrons in various orbits, which are called as Bohr-Bury Scheme.
1. Maximum number of electron in any shell should be 2n2 , where n is serial number of shell.
2. Maximum number of electron that exist in outermost shell or orbit of any atom is eight while maximum number is eighteen for penultimate shell.
3. According to this law, it is not necessary that another shell is formed after completion of 1st shell. A new shell is formed as number of electrons reaches eight in any orbit or shell.
Outermost incomplete shell of any atom is known as Valence Shell and electron present in incomplete outermost shell are known as Valence Electrons , which participate in formation of bond.

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Retrieved Text: Can someone explain how to calculate formal charges again? Or if there's another way aside from the equation we learned in class? And if we're trying to ionic element's lewis structure, do we had the charge to the number of electrons to the element/compound?
FC = VE (valence electrons) - LPE (lone pair electrons) - 0.5BE (half the bonding electrons).
I just think of it as 1. taking the number of valence electrons (which can be found on the periodic table) and 2. taking this number and subtracting the number of electrons surrounding the specific element (where a bond would only really be one electron). This way its only a two step calculation and a lot faster.
To calculate the formal charge, subtract the sum of the total number of lone electrons and total number of bonds (0.5 x total number of bonded electrons) from the number of valence electrons of that specific atom. All the atoms FC should add up to the compounds overall charge. It is preferred to have the lowest absolute value of FC for individual atoms. Like for CO2 it is preferred that each atom had a formal charge of 0,0,0 versus have 0,-1,+1.

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Retrieved Text: Gram atomic mass & Molar mass.
First recorded evidence that atoms existed.
Dalton’s theory was based on the premise that the atoms of different elements could be distinguished by differences in their weights.
o The indivisibility of an atom was proved wrong , for, an atom can be further subdivided into protons, neutrons and electrons. o The atoms of same element are similar in all respects , but isotopes of same element have different mass.
An electron is a negatively charged component of an atom which exists outside the nucleus. Each electron carries one unit of negative charge and has a very small mass as compared with that of a neutron or proton.
Since the ray was attracted to a positive electric plate placed over the cathode ray tube (beam deflected toward the positive plate) he determined that the ray must be composed of negatively charged particles.
E. Goldstein in 1886 discovered the presence of new radiations in a gas discharge and called them canal rays. These rays were positively charged radiations which ultimately led to the discovery of another sub-atomic particle.
Canal Rays: The positively charged radiation produced in the discharge tube at low pressure and high voltage are called canal rays.
Q.1 What was the model of an atom proposed by Thomson? Q.2 What is the nature of charge on electrons?
the gold foil without getting deflected. empty.
completely rebound on hitting the gold compared to the total size.
Limitation: In Rutherford’s atomic model , Nucleus & electrons are held together by electrostatic force of attraction which would lead to the fusion between them. This

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Retrieved Text: Conversion of light energy in electrical energy is based on a phenomenon called photovoltaic effect. When semiconductor materials are exposed to light, the some of the photons of light ray are absorbed by the semiconductor crystal which causes a significant number of free electrons in the crystal. This is the basic reason for producing electricity due to photovoltaic effect. Photovoltaic cell is the basic unit of the system where the photovoltaic effect is utilised to produce electricity from light energy. Silicon is the most widely used semiconductor material for constructing the photovoltaic cell. The silicon atom has four valence electrons. In a solid crystal, each silicon atom shares each of its four valence electrons with another nearest silicon atom hence creating covalent bonds between them. In this way, silicon crystal gets a tetrahedral lattice structure. While light ray strikes on any materials some portion of the light is reflected, some portion is transmitted through the materials and rest is absorbed by the materials.
The same thing happens when light falls on a silicon crystal. If the intensity of incident light is high enough, sufficient numbers of photons are absorbed by the crystal and these photons, in turn, excite some of the electrons of covalent bonds. These excited electrons then get sufficient energy to migrate from valence band to conduction band. As the energy level of these electrons is in the conduction band, they leave from the covalent bond leaving a hole in the bond behind each removed electron. These are called free electrons move randomly inside the

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Input Text: Read the passage below and choose the right answer to the following question (choices are smaller telescope or bigger telescope ):

Larger telescopes can collect more light.


Alan saw Venus through his old telescope. He then looked through his bigger, better telescope. Venus likely appears brighter through the smaller telescope or bigger telescope?

Target Text: bigger telescope

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Retrieved Text: A skygazer views Venus from the Giant’s Causeway near Bushmills, on the northeast coast of Northern Ireland. Giant’s Causeway is an area of about 40,000 interlocking basalt columns, the result of an ancient volcanic eruption some 60 million years ago.
A lone bright star now hangs low in the south during the early evening hours. First-magnitude Fomalhaut — often called “the Solitary One” — belongs to the constellation Piscis Austrinus the Southern Fish. From mid-northern latitudes, it climbs 20° above the horizon at its best. How solitary is Fomalhaut? The nearest 1st-magnitude star to it, Achernar at the southern end of Eridanus the River, lies some 40° away. It doesn’t appear quite as isolated as normal this year, however, because magnitude –0.1 Mars stands about 20° north of it.
Venus appears brilliant from the time it rises a little before 4 a.m. local time until close to sunrise some three hours later. It stands about 25° above the southeastern horizon an hour before the Sun comes up. Shining at magnitude –4.9, it appears slightly brighter today than at any other time during this morning apparition. (The difference is essentially imperceptible, however — it appears less than 0.01 magnitude brighter today than it did yesterday or will tomorrow.) When viewed through a telescope this morning, Venus spans 40" and appears one-quarter lit.
The variable star Algol in Perseus reaches minimum brightness at 9:53 p.m. EST, when it shines at magnitude 3.4. If you start watching it after darkness falls this evening, you can see it more than triple in brightness,

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Retrieved Text: When George Ellery Hale was 14 years old, he begged his father, a wealthy Chicago businessman, to buy him a telescope so he could watch the rare event of Venus passing between Earth and the Sun. Hale’s parents, pleased with their son’s interest in science, bought him the telescope, and, over the next 16 years, other professional-quality astronomical instruments. After he entered college, they built him his own laboratory, a brick building on their property.
Hale’s parents doted on him. He was often sick, and they had lost two other children to illness as infants. However, their support for his interest in astronomy turned out to be entirely justified. Hale was still in college, studying solar astronomy, when he invented the spectroheliograph, a device to photograph and analyze the Sun. The spectroheliograph would launch the design of telescopes dedicated to solar astronomy.
Hale went on to leave his fingerprints on the great American telescopes of his time. He would make plans to build a large telescope and obtain the financial backing. Then he would gather the people and materials to carry out the plan, and have the telescope built — all while working on ideas for the next, even bigger telescope. Hale was constantly trying to look deeper into the sky. He suffered from frequent depression and headaches, but nothing could keep him from his work on solar astronomy and stellar evolution, or his passion for building big telescopes.
His final project was the 200-inch telescope on Palomar Mountain. During the last few days of his life, Hale is

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Retrieved Text: Photo of the Week.. Saturn shows off its beautiful rings and banded cloudy surface, which is made of ammonia crystals. The rings consist of countless small icy rocks. The gap in the ring system, the "Cassini Division," is caused by gravitaional effects of orbiting satellites. The picture, as it appears through the telescope, is upside-down. Photo by Mark Killion.
Astronomy news for the week starting Friday, April 30, 2004.
The Moon passes through its full phase this week on Tuesday, May 4, rather well before moonrise in North America. As a result it will rise shortly after sunset in darkening twilight. It will also undergo total eclipse on that date, but since full (a requirement for lunar eclipse) takes place in the North American afternoon, the event will not be seen there. Europe and Africa, on the other hand, will get a fine view.
Venus tops the planetary list this week as it reaches its greatest brilliancy (for this orbital evening vista) on Sunday, May 2, when it hits "apparent magnitude" -4.5. (The magnitude scale is such that each division corresponds to a factor of 2.5 in brightness; the smaller the number, the brighter the object. The faintest stars visible without a telescope are magnitude 6) At that time Venus will be over eight times brighter than Jupiter (which will have a magnitude of -2.2), 16 times brighter than the brightest star, Sirius (magnitude -1.46), and a remarkable 275 times brighter than Mars, which has fallen to second magnitude and which attractively will lie up and to the left

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Retrieved Text: The waning crescent Moon stars in a series of conjunctions it this week's predawn sky as it passes Jupiter, then Venus, and finally Saturn.
A 13-percent-lit waxing crescent Moon passes 2° south-southeast of Venus in this image from the evening of September 8, 2013. On January 31, a slightly fatter, though waning crescent Moon passes a similar distance from Venus before dawn.
One of the sky’s most familiar constellations rules January’s sky from dusk until around 2 a.m. local time. Orion the Hunter appears conspicuous in the southeast after darkness falls and climbs highest in the south around 9 p.m. It then stands halfway to the zenith from mid-northern latitudes. The night sky’s brightest star, Sirius, trails about an hour behind Orion.
Mars continues to put on a nice show in January. Look for the Red Planet halfway to the zenith in the southwestern sky as darkness falls. The world shines at magnitude 0.8 against the much dimmer stars of southern Pisces. Tonight, Mars slides 0.9° south of the 4th-magnitude star Epsilon (ε) Piscium. A telescope reveals the planet’s 6"-diameter disk, but you likely won’t see any surface features unless you have exceptionally good seeing.
Last Quarter Moon occurs at 4:10 p.m. EST. The Moon doesn’t rise until nearly 1 a.m. local time tomorrow morning, however, by which time it will appear slightly less than half-lit. The Moon spends the morning hours set against the background stars of northern Libra.
Although Uranus reached opposition and peak visibility more than three months ago, it remains a tempting target. The outer planet appears

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Retrieved Text: Filter problems hamper Venus observations Sunspot, NM (Feb. 13, 2006) — Instrument problems have kept the team at the Dunn Solar Telescope from observing the planet Venus as they had hoped. “The filter on our infrared camera is leaking thermal radiation and keeping us from observing the planet,” said Dr. Nancy Chanover, the principal investigator from New Mexico State University in Las Cruces, NM. “Basically, we have excess heat shining on the detectors. We have exhausted all possibilities for working around this after a valiant effort by the Dunn Solar Telescope staff.” Chanover believes that the technique for observing Venus using a solar telescope and adaptive optics is sound, and hopes to attempt the observations again after resolving the problems with the filter. Dates for another attempt have not been set.
The planet Venus is best known for the thick layers of clouds that veil its surface from view by telescopes on Earth. But the veil has holes, and a New Mexico State University scientist plans on using a solar telescope to peer through them to study the weather on Venus.
“Observations of Venus from a nighttime telescope at a single location are very difficult because Venus is so close to the Sun in the sky,” said Dr. Nancy Chanover, a planetary scientist at NMSU in Las Cruces, NM. “You can observe it for about two hours at most.” Then the Sun rises and blinds the telescope (or Venus sets, depending on the time of year).
“Alternatively you can find a telescope designed to be open when the Sun

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Retrieved Text: Visit the observatory at the National Air and Space Museum.
It’s not every day that a telescope gets a birthday cake. But this telescope was special. It had recently traveled 400 miles to start a new life showing visitors the sky above the National Air and Space Museum in Washington, D.C., and on March 1, 2017, it was turning 50 years old. Half a century ago, its story began with a pianist.
Chester Sheldon Cook earned money for his family in two ways: He gave piano lessons, and he made high-quality optical devices during World War II. A lover of harmony and math, he was naturally drawn to astronomy. So great were his contributions to the Amateur Telescope Makers of Boston that his friends memorialized him when he died by purchasing a large telescope and naming it for him. The Cook Memorial Telescope, built by Boller & Chivens, with a 16-inch mirror, was designed for observing planets, stars, and asteroids. The Harvard-Smithsonian Oak Ridge Observatory bought the telescope in 1967 and for decades astronomy students there used it to study the sky.
When Oak Ridge closed in 2005, Cook’s telescope went dark with it. For the International Year of Astronomy in 2009, Smithsonian history of astronomy curator David DeVorkin wanted to put a telescope at the National Air and Space Museum on the National Mall, where more than eight million annual visitors would have access to it. Harvard agreed to loan the telescope to the Museum, with support from the National Science Foundation.
A truck ride and a crane lift

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Retrieved Text: Photo of Venus over a frozen lake.
Venus (upper left) over a frozen Colorado lake. The dark spots barely visible over the tree on the left is a flock of geese a few hundred meters away.
Apropos of nothing, last night I took this picture just after sunset. The sky was still bright enough to illuminate the lake at a low angle, accentuating the ripples and color variations of the thin ice covering the liquid below… but also dark enough that brilliant Venus was easily visible, dominating the sky to the south.
Yesterday was an irritating day for a number of reasons; everything I was doing seemed to get bollixed and impeded by trivialities. It was nothing major, but enough to be frustrating and put me in a dim mood. But then I saw this. It certainly didn’t fix any of the issues of the day, but it just as certainly put them in their place.
Venus orbits closer to the Sun than we do, and due to the sometimes non-intuitive dance of the planets, currently appears to be moving away from the Sun in the sky. That will change on Jan. 12, when it reaches maximum elongation from the Sun. From that point forward it appears to change direction, moving from east to west, and once again will slowly move toward the Sun in the sky. Slowly at first, that is; as it gets closer to Earth its speed will appear to increase, and it will close the distance to the Sun rapidly toward the end of February and

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Retrieved Text: This is a true story of a man who saw UFOs as an ex-air traffic controller of Japan Air Self-Defense Force (JASDF) and a comet hunter.
His name is Tsuruhiko Kiuchi (1954 -), a Japanese comet hunter who had an amazing experience of seeing UFOs.
6 How to Observe UFOs?
As a comet hunter, Kiuchi made outstanding achievements in comet hunting.
On March 16, 1990, he discovered Comet Cernis-Kiuchi-Nakamura (1990b).
On July 16, 1990, he discovered Comet Tsuchiya-Kiuchi (1990i).
On January 7, 1991, he rediscovered Comet Metcalf-Brewington (1906VI=97P/1906 V2).
On September 27, 1992, he rediscovered the Comet Swift-Tuttle (109P/Swift-Tuttle).
Before the rediscovery, it was predicted that the Comet Swift-Tuttle would return between 1979 and 1983, but it didn’t show up.
In 1990-1992, comet hunters around the world usually calculated cometary orbits using a computer and spotted a comet on a photographic plate.
However, Kiuchi calculated cometary orbits using a handy calculator and spotted comets with a large binocular telescope in Mt. Yatsugatake.
Thus, Kiuchi became famous as a Japanese amateur astronomer to hunt comets around the world.
No, there are no UFOs.
Since the existence of UFOs has not been verified scientifically so far, he had no choice but to officially say that as a comet hunter.
However, in contrast with his official answer, Kiuchi has seen UFOs several times.
According to Kiuchi, stargazers using optical telescopes often see UFOs.
When they observe the stars, they accidentally find UFOs.
Actually, Kiuchi himself has seen UFOs several times.
One day when an astronomical observation event was held, Kiuchi had a chat with staff member of an astronomical observatory in a waiting room.
Actually, I have seen

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Retrieved Text: If you haven't yet seen the Venus, Jupiter and Moon trio and you're not into waiting until 2052 to catch a glimpse of their next rendezvous, then this may be your opportunity to see what we saw in the heavens last night.
Venus (named after the Roman goddess) and Jupiter (after the Roman god of gods) are the second and fifth furthest planets from the sun respectively.
If I'd had 4 hours to take a drive I guess the best place from which to view this would have been the observatory at Sutherland. About 18km outside of the town one finds the location of SALT, the Southern African Large Telescope - the largest telescope in the southern hemisphere. Sutherland is in a cold part of the country, practically in the middle of nowhere, far away from city lights. I've never been sure exactly where Sutherland is, so I took some time to track it down on trusty Wikimapia. Click through to the Wikimapia topographical map to get an idea of where the telescope is, and then zoom in - the guys from Google have made a pretty decent photo available for us.
Posted in General on Tuesday, 2 December, 2008 by Paul.

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Retrieved Text: This is where I’ll be this evening…letting this beauty in.
Thanks for reminding us, Maria W!
February 26, 2009: Be careful, this sort of thing can cause an accident!
(1) Venus is at maximum brightness: magnitude -4.6. The planet is twenty times brighter than Sirius, the brightest star in the sky. It is so luminous that it can actually shine through thin clouds and cast subtle shadows on the ground.
(2) As seen from North America, the Moon-Venus separation is only a little more than 1o. Stick up your thumb and hold it out at arm’s length. Venus and the Moon will fit comfortably behind the thumb-tip. Tight conjunctions like this are the most beautiful of all.
(3) Not only is the Moon a crescent, but so is Venus. A small telescope pointed at the glittering planet will reveal a slender 20%-illuminated disk.
Add it all together and you’ve got a major distraction. Evening drivers should pull to the verge. Staring at Venus and the Moon could be riskier than texting!
Venus is a crescent because, like the Moon, it has phases. The planet can be be full, gibbous, new, or anything in between. The illuminated fraction we see on any given date depends on how much of Venus’ nightside is turned toward Earth.
The crescent phase of Venus occurs when Venus is close to Earth, very big and bright. The full phase of Venus, on the other hand, occurs when Venus is on the opposite side of the Sun, far away and relatively dim.
Crescent Venus is so bright, you can see it in

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Retrieved Text: For the next few nights, bright Venus and Jupiter will be joined by other planets at dusk.
Skywatchers have been watching with anticipation lately as Jupiter draws close to Venus in the evening twilight sky.
This week, as Venus and Jupiter draw close for a March 15 conjunction, they are joined by the planet Mercury somewhat lower in the sky. Observers with binoculars may also be able to spot Uranus, just below Mercury, and dwarf planet Ceres nearby. Another dwarf planet, distant Eris, is also close, but too faint to be seen through amateur telescopes.
The sky map of Jupiter and Venus for this story shows how the planets and other solar system objects appear in the night sky. Jupiter and Venus are currently the brightest of the planets, but present some remarkable contrasts to anyone with a small telescope.
Through a telescope, Jupiter appears almost twice as large as Venus, though that will change as Venus swings closer to Earth over the next few months. When Venus is closest to Earth on June 5, it will appear three times larger than it is at present. At that time, it will pass between Earth and the sun, appearing as a tiny black spot against the sun. This Venus transit occurs less than twice a century. The 2012 transit of Venus occurs on June 5 will not be repeated until the year 2117.
The atmospheres of the two planets are also strikingly different. Jupiter shows a complex pattern of cloud belts and spots, while Venus has only a bland, smooth white cloud

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Retrieved Text: A total eclipse of the Moon Sunday night highlights a week that also boasts a stunning predawn conjunction between Venus and Jupiter.
The Full Moon should turn orange at the height of the lunar eclipse on the night of January 20/21.
For those who recently caught the observing bug, the so-called Summer Triangle must seem like a huge misnomer. That’s because this asterism remains on view after darkness falls in January. Look for Vega, the fifth-brightest star in the sky and the brightest triangle member, low in the northwest. Deneb lies above Vega and about one-third of the way to the zenith. Deneb marks the top of another asterism, the Northern Cross, which stands nearly straight up from the horizon on January evenings. Altair, the third triangle member, scrapes the western horizon and sets around 6:30 p.m. local time.
Although Uranus reached opposition and peak visibility nearly three months ago, it remains a tempting target. The outer planet appears nearly 60° high in the southwest after darkness falls and doesn’t set until after midnight local time. The magnitude 5.8 world lies in southeastern Pisces, some 1.2° north of the 4th-magnitude star Omicron () Piscium. Although Uranus shines brightly enough to glimpse with the naked eye under a dark sky, use binoculars to locate it initially. A telescope reveals Uranus’ disk, which spans 3.6" and shows a distinct blue-green hue.
Anyone with clear skies across the Americas can witness this week’s biggest event: a total eclipse of the Moon. The Full Moon, which arrives officially at 12:16 a.m. EST tomorrow morning

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Retrieved Text: Venus is one of the four terrestrial type planets, meaning it has a rocky body. Due to its similarity in size it is often referred to as the Earth’s twin.
Where is Venus located in the solar system?
Venus is the second planet in our solar system, located between Mercury and Earth.
Since the planet is easily visible as a bright white disk in the night sky its existence was well known amongst ancient civilizations. It was first scientifically observed by Galileo Galilei in the 17th century. Using a self designed telescope, he confirmed the various phases of Venus.
Venus, like all other planets in our solar system, was formed roughly 4.5billion years ago.
When the planet is observed from a powerful telescope it appears to be yellowish-white in color. This is due to the thick layer of clouds that surrounds its atmosphere.
Venus appears relatively brighter than most other celestial objects due to its close proximity to Earth. Another reason is that the cloud cover reflects almost 70% of the sunlight received by the planet making it more luminous and radiant.
Venus does not have any rings.
Venus and Mercury are the only two planets in our solar system that are devoid of any natural satellites or moons.
How is the surface of Venus?
Very little is known about the surface of Venus as the constant cloud cover has prevented scientists from studying its geology. However, recent space missions have revealed that it is a harsh place filled with craters, volcanoes and lava plains.
What is the temperature in Venus?
The planet is extremely hot with the

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Retrieved Text: They call 2013 the Year of the Comets. When you can have 3 naked eyes comets gracing the sky in a year, 2013 definitely deserves the title.
The first one is called Comet PANSTARRS. PANSTARRS, stands for Panoramic Survey Telescope & Rapid Response System, is the telescope that discovered the comet. This 1.8-m telescope is located atop the Haleakala volcano in Hawaii. This comet already put on a great show in the southern hemisphere, and now our fellow Malaysians also had captured the comet in Negeri Sembilan and Sawarak.
It was estimated that the comet is the brightest between March 8 – 12, with roughly the magnitude of zero. But bear in mind that a comet’s magnitude is the estimate of the light emitted by the whole (extended) object, while a star is a point of light. Thus, when Comet PANSTARRS reaches a magnitude of zero, it won’t appear as bright as a zero magnitude star because the comet’s light will spread out over a larger area.
The video below shows the position of the comet for Kuala Lumpur, Malaysia from 8 to 30 March. The chart was produced using Stellarium. If you do not have Stellarium, go and download one now! It’s an open source planetarium software that can show you how the sky looks like anywhere on Earth. And since Comet PANSTARRS is the hot topic now, you wouldn’t want to miss it. So, once you have installed Stellarium, follow this video to add Comet PANSTARRS (and other comets). Now you can know when and where the

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Retrieved Text: When it is dark enough to see a few stars in the sky during evening twilight, look to the East and Southeast. About a third of the way from the horizon to the zenith (straight up), 3 bright “stars” can be seen spread out from due East to the South-South-East (see the chart below).
View of the East-Southeast sky in the early evening. The star Procyon is located between Mars and Sirius. Chart made with Stellarium.
The 3 “stars” are, in fact, 2 stars and a planet: Sirius, Procyon, and Mars. Let’s start with the Sirius, the southernmost and brightest of the three. Not only is Sirius the brightest of the three (at magnitude -1.5), it is the brightest star in the entire night sky. Only the Moon, Venus, Jupiter, and occasionally Mars are brighter.
Relative to the Sun, Sirius is twice as massive, has a radius 70% larger, and is 25 times more luminous. Still there are many stars in the sky that are even larger and more luminous than Sirius. The reason for its status as the brightest star in the sky is due more to its relatively close distance than its luminosity. At a distance of 8.6 light years, it is the 5th closest stellar system.
Sirius is an A-type star which causes it to shine with a white-blue color. Many times, though, the star will appear to rapidly change color. The reason for this is due to the Earth‘s atmosphere. Turbulence in the atmosphere causes the star’s light to be “bounced” all over the place. The

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Retrieved Text: The first time I heard about Zeiss Telementor telescope it was reading an email by my friend Luis Arguelles, explaining me how wonderful was that small 63 mm refractor.
Very strange to fall in love for a so small telescopes, especially in an amateur astronomy world were almost everyone is running toward bigger and bigger aperture.
But I was able to observe through the Telementor of my friend John Ryan in September 2002, and I found out in that lens an incredible optical quality.
I was completely astonished by a 50% phase Venus without any chromatic aberration, it was like to observe in an APO telescope … Coming back home I began to study the way to get such a lens for my observing needs.My friend Tito got the same illness, and began immediately to hunt for a Telementor: within a month, with the help of Luis, we found an amateur living near London, selling his old Telementor. After some email to adjust price and manage the shipping, the telescope was soon in Tito’s home, with a complete happiness of the new Zeiss-owner.
(new) from Baader Planetarium firm in Germany – sold in Itay by Unitron Italia.
I purchased not only the C63 doublet (63 mm diameter, focal length 840 mm) but also the C50 one (50 mm diameter, focal lenght 540 mm). Both achromats were mounted in aluminum tubes, with the right thickness to obtain the seat for the cell in front – the cell was hold in place by a screwed cap, having also the function of dew-shield.
The focusers

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Retrieved Text: Click on one of the small images of the table below to get to a bigger image, the images are presented chronologically. The last image shows the Zodiacal light as well.
Two auxiliary telescopes (1.8m diameter) and UT1, one of the 8m unit telescopes of the Very Large Telescope (VLT), looking quietly at the Moon, Venus (brightest planet on the picture), Mercury (Between Venus and the Moon) and Mars (redish point above Mercury and Venus).
Two auxiliary telescopes (1.8m diameter), UT1 and UT2, two of the four 8m unit telescopes of the Very Large Telescope (VLT), looking quietly at the Moon, Venus (brightest planet on the picture), Mercury (Between Venus and the Moon) and Mars (redish point above Mercury and Venus).
The image below shows the same scene somewhat later with the stars and zodiacal light visible, the exposure time was larger, explaining why the dome and ground can be seen.

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Retrieved Text: Originally Published: November 20, 2018 11:47 a.m.
When Galileo Galilei began studying the evening sky with his telescopes, astronomy took a huge leap forward.
Though Galileo did not invent the telescope, he was the first to use it systematically to observe celestial objects and record his discoveries. His book, Sidereus Nuncius, or The Starry Messenger, was first published in 1610, which made him famous. In it he reported his observations of the moon, Jupiter, Venus, the sun and objects in the Milky Way. These observations and his interpretations of them eventually led to the demise of the geocentric, Earth-centered, model of the universe and the adoption of the heliocentric, sun-centered, model as proposed in 1543 by Nicholas Copernicus.
The instruments Galileo used were a type of home-made refracting telescope, which had a convex objective lens mounted at one end of a long tube with a concave eyepiece mounted at the other end. Though his initial version only magnified eight times, he soon created a telescope having a power of 20 times, which he used for his observations in the Sidereus Nuncius. The main problem with his instruments was their very narrow field of view, about half the width of the moon. Typically, one of Galileo’s telescopes had a focal length of 52-inches with a one inch aperture, which magnified 14 times. Through his systematic use and refinement of these telescopes, Galileo would make several unique discoveries that would change the world and the way people see the universe.
According to Aristotle, the moon was in the heavens above the sublunary

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Retrieved Text: Today we had a great DTM seminar by Rachel Osten from the Space Telescope Science Institute (STScI). She talked about stellar activity and coronal mass ejections (CMEs).
A coronal mass ejection in time-lapse imagery obtained with the LASCO instrument. The Sun (center) is obscured by the coronagraph’s mask.
Osten pointed out that these huge eruptions from stars are important for several reasons. For example, the energy and frequency of CMEs depend on several properties of stars, including their age, rotation rates, and magnetic fields. In general, as stars age, their rotation rates drop, usually reducing the strength of their magnetic fields and the amount of CME activity. And so learning about CMEs can tell us about stellar evolution.
When a star fires off a CME, it typically flares or brightens a bit (see figure at right), and since we can’t see stars other than our Sun up close, we can use the temporary brightening of those stars to study their flare activity. Osten talked about one of her projects to use data from the Hubble Space Telescope to look for flare activity for many stars near the constellation Sagittarius.
That project had a surprising result: many stars that were thought to be older than the Sun actually showed MORE flare activity than they should have. This result might mean these stars actually have previously unknown binary companions that kept the stars spinning quickly and thereby keeping their flare activity up.
Stellar flares may also be important for planetary habitability. For example, a big stellar flare can actually disrupt the atmosphere of

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Retrieved Text: Mercury the nearest planet to the Sun is visible as both an evening and morning object during January. The small elusive planet can be seen for the first few days of the month low down above the southwestern horizon after sunset (mag. -0.3). During this time it's slightly easier to spot Mercury from tropical and southern locations. However it doesn't take long before the fading planet draws into the Sun and is lost to the bright twilight glare.
On January 14th, Mercury passes through inferior conjunction. Subsequently it re-appears in the morning sky and may be seen towards month's end low down above the ESE horizon, 45 minutes before sunrise (mag. +0.0). Much brighter Venus (mag. -3.9) is positioned 7 degrees west of Mercury.
Venus is now fading in brightness but continues to be visible as a brilliant morning object before sunrise towards the southeast (Northern Hemisphere) / east-southeast (Southern Hemisphere). The planet starts the month at magnitude -4.1, ending it at magnitude -3.9. Although now limbering towards the lower end of its brightness range it remains unmistakable, a dazzling beacon of light hovering above the horizon.
At the start of January, Venus rises up to 3 hours before the Sun although from northern temperate latitudes the visibility period shortens considerably as the month progresses. By the end of January it reduces to just over an hour. From Southern Hemisphere and equatorial regions it still rises up to 2.5 hours before the Sun at months end.
On January 6th, Venus passes 6 degrees north of red supergiant Antares (α Sco

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Retrieved Text: Astronomical observations – very interesting. One of the brightest heavenly bodies available for observation Amateur astronomer, is Venus. How to detect this planet in the sky?
Armed with a telescope. Venus looks in the sky like a bright star, it can be seen with the naked eye, but for scientific research equipment is required.
Venus orbits the Sun faster than Earth, so it is possible to observe 2 times a day. Go to the point of observation either in the morning or in the evening. In the evening Venus should be sought in the West and before sunrise in the Eastern side.
Install telescope and make the necessary calculations. You need to understand what is at the moment the Ecliptic plane. It is the path followed by the Sun across the heavens. Venus, like most other astronomical bodies are best observed in the period of elongation, that is, at a time when the planet is farthest from the Sun. The maximum angle between Venus and the day the sun never exceeds 47 degrees. Day we are interested in Planeta may not be visible due to background sunlight. We will be able to notice it only when it deviates from the Sun not less than five degrees.
Calculate the perfect time for observation. Venus will be visible for 20 minutes before sunrise and 20 minutes after sunset. It is best to observe its appearance in the sky at the day of the summer and winter solstice, i.e. during the period of greatest elongation.
Every seven months, this planet becomes the brightest object

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Retrieved Text: If somebody tells you they saw a pair of UFOs this week, ask them to be sure they weren’t just gazing at Venus and Jupiter.
The two planets have been moving toward one another in the night sky for months now, and star gazers get a special treat this week as they line up for a planetary conjunction.
Venus and Jupiter get cozy about every 13 months, but this particular tango of the sky’s two brightest planets is special because they’ll be extra visible during the long evening in the Northern Hemisphere—and that won’t happen for another several years.
By the time it peaks this Thursday night, the planetary conjunction will be visible above the western horizon for four hours. Venus, much closer than Jupiter, will be the brighter of the two planets, even though it’s much smaller in size. So take off the tinfoil hat and dust off the telescope; this close encounter of the celestial kind is worth watching.

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Retrieved Text: This story began about a year ago when the world of science celebrated the 300th anniversary of Mikhail Vasilievich Lomonosov (1711-1765)—a great polymath, founder, and key figure of Russian science. Despite enormous fame in Russia, comparable to that of Ben Franklin in the US (e.g., even Russia’s leading Moscow State University is named after Lomonosov, it’s founder), Lomonosov is still curiously unsung in the West, as indicated in an excellent article “Mikhail Who?” by Robert Crease in the Nov.11 issue of Physics World magazine. The general public got an opportunity to learn about this outstanding Russian genius in a series of publications, such as my article in the Feb. 2012 issue of Physics Today. Discovery of the atmosphere of Venus during its transit over the Sun’s disc in 1761 is one of the most remarkable of his numerous scientific achievements. Observation of a "pupyr"—the Russian term for a blister/bulge/arc of light around the part of Venus off the Sun’s disc early at the egress—was one of the keys which allowed him to conclude that: "…the planet Venus is surrounded by a significant air atmosphere similar to (if not even greater than) that which surrounds our terrestrial globe". Lomonosov published his report in Russian and in German, giving the most detailed description of the aureole effect, and a complete and correct physical explanation of the phenomena as refraction of the solar rays in the atmosphere of Venus, being accorded priority for this important observation (see the English translation at https://arxiv.org/abs/1206.3489). Many astronomers in 1769, 1874 and 1882

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Retrieved Text: Over the years I've spoken with many amateur astronomers about how their interest in the sky was fired-up upon receiving their first telescope. I can still remember when I was 9-years old peering at the moon through my own new telescope; the view was absolutely entrancing and ever since – for more than 40-years – I have never tired looking in looking up at the sky.
Perhaps you are now seriously considering purchasing a telescope, either for yourself or for someone else.
Here's a brief overview of what you must know first.
It's easy to look at the spectacular images in astronomy books or on the web and arbitrarily assume that you're going to see similar sights through a small telescope. But remember that most of those stunning views were likely taken with large observatory instruments and through cameras employing long time exposures, which bring out all the intricate details and colors.
That's not, however, what you're going to see through your backyard telescope.
But a good small telescope can reveal a surprisingly rich and varied array of celestial wonders. Let's begin with our nearest neighbor in space, the moon. Because it's the largest and brightest object in the nighttime sky, the moon is a natural target for small telescopes.
Even 30-power – which can be found in a relatively small and inexpensive setup – will show a breathtaking panorama of smooth dark regions and rugged highlands pockmarked by hundreds of craters. With higher powers, the moon completely fills the eyepiece field. By letting the moon slowly drift across your line of

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Retrieved Text: On the morning of Saturday December 4, Venus will be at its brightest for the current morning apparition.
This week Venus will be at itsbrightest for many monthsto come and hit its peak as a brilliant jewel in the sky on Saturdaymorning.
Due to a combination of its orbitalpath and amount ofreflected sunlight, on Saturday (Dec. 4), Venus will shine so brightlyitshould be unmistakable to skywatchers with a clear morning sky.
This sky mapshows where to look to see Venus onSaturday morning.
As the Earth and Venus circlearound the sun in theirrespective orbits, their changing geometry causes Venus? brightness tovary. Asyou might expect, it generally tends to be brighter when it is closerto Earth.However, this isn?t always true because Venus is an "inferior"planet.
Astronomers use "inferior" to mean"closerto the sun" rather than "lower in quality." So, the planetsMercury and Venus are both known as "inferior planets."
As a result of its orbit beingcloser to the sun than theEarth's, Venus passes between the Earth and the sun once every 584days. Thisis known as "inferiorconjunction," and last occurred on Oct. 29.
Even though Venus was closest toEarth on that date, itwas ? for all intents and purposes ? invisible. That's because on Oct.29 Venuswas almost entirely backlit, except for a tiny amount of sunlightleakingthrough its upper atmosphere.
But over the last five weeks, Venushas moved along itsorbit such that, while it is farther from the Earth than it was in lateOctober,it is now more brightly illuminated by the sun from the side. Thismakes moreof Venus'cloud tops visible and gives the planet a brilliant shine.
On Dec. 4,

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Retrieved Text: This image was taken from the Mount John Observatory at Mount John on the morning of February 4.
For the first part of this year, Sky Watch columnist Ian Griffin will be spending four nights per month at the University of Canterbury's Mount John Observatory above Lake Tekapo.
I'm taking leave from my day job at Otago Museum to work on an outreach project, the aim of which is to use one of the telescopes to obtain high-quality pictures of some of the most stunning celestial objects in the southern sky. My first ''run'' on the telescope took place last weekend, and I have to say that the results are already pretty exciting.
Photographing distant astronomical targets through a large telescope is always fascinating. However, one of the greatest pleasures of an observing run at Mount John is not using the telescopes. It is actually being able to leave the telescope dome between exposures and gaze at the truly exceptional Mackenzie Country sky.
At around 4am on my last night at the observatory, feeling sad that my time on the mountain was coming to an end, I stepped outside for a final look at the heavens. Almost instantly my eyes were drawn to an incredible scene in the east, where Venus was just clearing the horizon.
Despite its low altitude, Venus was absolutely stunning; a bright blue-white point of light appearing so bright that I was convinced it was casting shadows. Above Venus, Jupiter was also prominent. Its bright yellow-white colour making it stand out from the background sky.
As my eyes

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Retrieved Text: __1643: __Italian astronomer Giovanni Riccioli discovers a faint glow on the night side of the planet Venus. Other astronomers over the ensuing centuries will also observe the Ashen Light, but one of the longest-running mysteries of astronomy still defies conclusive explanations.
Riccioli was an astronomer of some repute. Working in the first generation after Galileo, he discovered that Mizar (the middle star in the handle of the Big Dipper) is actually a double star — the first one known. He also discovered satellite shadows on Jupiter and published a map of our moon's surface. The names he assigned (e.g., Sea of Tranquility, Sea of Storms) are still used today.
The faint luminescence Riccioli saw 366 years ago has been seen many times since, by professionals and amateurs alike. It's also not been seen by many who were looking for it. Its apparent intermittence and the lack of a satisfactory explanation has led some to chalk it up to observer error, distortion caused by Earth's atmosphere and/or artifacts induced by telescope optics.
But, still: 366 years of similar observations? Those who've seen the Ashen Light of Venus report it looks a lot like the reflected "Earthshine" that sometimes casts a dull glow on the moon, but not even that bright. It's most easily sighted when the dusk edge of the sunlight on Venus faces Earth.
The U.S. Pioneer mission and the Soviet Venera 11 and 12 landers looked for it without any luck. The Keck I telescope in Hawaii did spot a faint, green glow consistent with the 558-nanometer emission of

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Retrieved Text: Welcome to the June night sky. This is the month of the summer solstice when the Sun is as far north in the sky as it can ever get and, therefore, it will be at its highest altitude at local midday.
This also marks the beginning of summer in the northern hemisphere and this year it is on June 21. This will also be approximately the longest day and shortest night of the year.
For anyone north of the Arctic circle, the Sun will not set, giving 24 hours of daylight but, due to its low altitude in the sky, the Sun will not heat the ground very much, so it will be providing light but not warmth.
The brilliant planet Venus is still visible in the west high and bright as darkness falls. And whilst looking at Venus, right behind you will see the giant planet Jupiter rising.
Now Jupiter has just passed opposition, so it is still a large object in any telescope.
The next jewel to be seen in the night-sky through a small telescope is the ringed planet Saturn. This planet is at opposition on June 27 and the rings are still tilted towards Earth, making the view of Saturn an unforgettable sight in a small telescope.
Saturn rises in the late evening in the northern part of the constellation of Sagittarius. The full Moon is near to Saturn on the night of the 27th.
The red planet Mars is now in the constellation of Capricorn and rises in the southeast about two hours after Saturn. This planet is

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Retrieved Text: Admiral Dean walked in to his office, it was a pretty large room, for an office that is, there was some plain white paint on the walls and roof with a nice brown carpet covering the floor and a nice window behind my steel desk.
In the window you could see another building, mostly grey with some large white lines to indicate where the different offices where, most of them also had a window identical to mine, but between the buildings there was a little garden to look at.
Dean pulled out his little chair, it was a standard office chair but it was very comfortable and sturdy.
He then sat down and opened up his green laptop and pressed the power button, typed in the password ‘’Leanehound’’.
Leane was his wife and he loved dogs, he always had one.
We need another mechanic to fix the mechs in time for the assault, I have to supervise the progress so you have to find a mechanic and send him here ASAP.
He doesn’t have to be anything special; we just need someone who can follow orders.Dean proceeded to look at available crew in the Nebula, the human space explorers.
That was the one he needed, before bothering to look at the rest, thirty available crew showed up, four recommended, he read the recommended first.
Performance: A very experienced mechanic who has been on sixteen short missions and two long missions, mostly a hard worker but can get very frightened when things are really at stake.
Performance: A very high tempered mechanic who doesn’t go on

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Retrieved Text: For casual stargazing, the most rewarding part of the sky this month lies to the east and southeast in the early hours before the Sun rises. There’s so much to see here, especially from December 5-8, you need to start early before the sky brightens. The simulation below, from Stellarium, shows you what to look for.
A waning crescent Moon joins Venus, Mars, Jupiter, the bright star Spica, and Comet C/2013 US10 (Catalina). Simulated view for December 6, 2015 from Stellarium. Click to open in a new window.
At the eastern end of this long chain, you find the planet Venus, the brightest object of this morning congregation. The planet shines at magnitude -4.2 and presents a 17″-wide disk about 2/3 illuminated when viewed in a telescope. The planet is slowly getting fainter and moves back towards the rising Sun as December progresses.
Venus guides your way from December 6-10 to Comet C/2013 US10 (Catalina). The comet will lie about 5° east of Venus during these days, though it will move northward slightly from day to day on a beeline towards the bright star Arcturus on January 1, 2016. A pair of binoculars will make the comet plainly visible in the same field of view as the bright planet. The slender waning crescent Moon will also lie within a single binocular field of Venus and the comet on Dec. 7. It might make for a good photo-op as well.
West of Venus and the comet, you will find the icy-white giant star Spica, the brightest star in the constellation Virgo.

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Input Text: Read the passage below and choose the right answer to the following question (choices are greater or smaller ):

The more carbon atoms a hydrocarbon has, the greater the number of isomers.


If Jim is comparing hydrocarbons and he finds one that has more carbon atoms, the number of isomers that hydrocarbon contains is greater or smaller?

Target Text: greater

#### Retrieved Documents ####

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: Hydrocarbon, an organic chemical compound composed of carbon and hydrogen. Hydrocarbons may be gases, liquids, or solids. In nature, they are found mainly in plants, petroleum, natural gas, coal, and oil shale. Most burn readily and dissolve more readily in alcohol than in water. Some are toxic and some form an explosive mixture with air. Hydrocarbons are used as fuels and solvents and in the manufacture of industrial chemicals, explosives, plastics, synthetic rubber, dyes, drugs, and other products.
More than 100,000 hydrocarbons are known. The main reason there are so many of these compounds is that carbon atoms can unite in many different ways to form complex chain or ring frameworks. Different arrangements of atoms yield different molecules. For example, the formula C30 H62 (30 carbon atoms and 62 hydrogen atoms) represents 4,111,846,763 possible isomers—compounds whose molecules differ only in structure.
In chemistry, compounds closely related in structure to hydrocarbons are called hydrocarbon derivatives. Such compounds consist of carbon, hydrogen, and other elements, usually oxygen, nitrogen, chlorine, phosphorus, or sulfur. They are often named for the hydrocarbons to which they are most closely related. For example, the organic chloride compound most closely related to ethane is called ethyl chloride. Hydrocarbons and their derivatives form a large part of the subject matter of organic chemistry.
Hydrocarbons are divided into two main groups according to structure—aliphatic (or acyclic) hydrocarbons and cyclic hydrocarbons. They are further divided into groups of compounds having similar chemical properties. Members within a group are called homologs, and each complete group is called a homologous series. Neighboring

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Retrieved Text: Chapter L3 Section 4 Organic Compounds The Four Bonds of a Carbon Atom More than 90% of all compounds belong to a group called organic compounds. Organic compounds are covalent compounds composed of carbon-based molecules. Fuel, rubbing alcohol, sugar, cotton, paper and plastic belong to this group. All organic compounds contain carbon. Each carbon atom has four valence electrons so each carbon atom can make four bonds with four other atoms.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Carbon Backbones Structural formulas are models that are used to show how atoms in a molecule are connected. Each line represents a pair of electrons that form a covalent bond.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Many organic compounds are based on the types of carbon backbones shown below. Some compounds have hundreds or thousands of carbon atoms as part of their backbone.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Organic compounds may also contain hydrogen, oxygen, sulfur, nitrogen, and phosphorus. The next slide shows three models of carbon backbones.
Section 4 Organic Compounds Hydrocarbons and Other Organic Compounds Many organic compounds contain several kinds of atoms, but some contain only two. Organic compounds that contain only carbon and hydrogen are called hydrocarbons. There are three types of hydrocarbons: saturated hydrocarbons, unsaturated hydrocarbons, and aromatic hydrocarbons.
Chapter L3 Section 4 Organic Compounds Hydrocarbons, continued Saturated Hydrocarbons An alkane, or saturated hydrocarbon, is a hydrocarbon in which each carbon atom in the molecule shares a single bond with

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Retrieved Text: Crude oil, as it is taken from the earth, is a very complex mixture of hydrocarbons.
As might be expected, the term hydrocarbon refers to the hydrogen and carbon atoms linked together and forming a majority of the individual molecules that are present. Having been transformed from living organisms being subject to heat and pressure over millions of years, the crude is termed to be an “organic” material. In addition to hydrogen and carbon, there are small amounts of other atomic elements that are present and mostly incorporated into the hydrocarbon molecules. The most common of these are nitrogen and sulfur. As part of the hydrocarbon, they are referred to as “hetero-” atoms. Heavier crude may also contain some inorganic materials such as nickel, vanadium, and iron, which are removed during refining.
Hydrocarbons form in an extraordinarily large number of configurations. They range in size from the simplest methane molecule, which contains one carbon atom and four hydrogens, to heavy asphaltic resins with structures that have not been fully mapped. Because we are dealing with mineral oil–based lubricants, we are interested in molecules of a size that fit into the range of approximately 15 to 95 carbon atoms long, corresponding roughly to a boiling range of about 300–700°C. In addition, as the number of carbon atoms in a molecule increase, the number of different ways that a molecule can be structured increases dramatically. Although many different arrangements of molecules may be imagined, for practical purposes, petroleum hydrocarbons are generally classified in a limited number of ways.
Consider the list

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Retrieved Text: A major class of organic compounds where carbon and hydrogen molecules are arranged in straight or branched chains. A type of hydrocarbon . Includes alkane s, alkene s, and alkyne s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where all of the carbon-carbon bonds are single bonds. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a double bond. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a triple bond. One of three major classes of aliphatic hydrocarbon s.
Molecules which are almost entirely carbon and hydrogen, but have had at least one chlorine atom introduced to them that has replaced one of their hydrogen atoms.
A hydrocarbon (molecule of carbon and hydrogen only) with 27 carbon atoms that is the parent structure of all mammalian steroid s.
Any of several enzyme s that put double bonds into the hydrocarbon areas of fatty acid s.
Any in a family of over 200 chlorinated organic chemicals (all heterocyclic hydrocarbons). The term is most commonly applied to a particular chemical, 2,3,7,8-tetrachlorodibenzo-paradioxin (2,3,7,8-TCDD, simply called TCDD), which is an impurity in the defoliant Agent Orange and in the pesticide 2,4,5-T (see auxin ). Dioxins are also produced when chlorinated materials such as plastics are burned. Dioxins are known to cause skin diseases (chloracne), birth defects, miscarriages, and cancer .
A

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: There are 5 lectures in this section of science wherein you are going to learn about Carbon and its compound. This is a very important chapter of Science and accounts for about 23 marks with periodic classification of elements. In Carbon and its compound You will learn the following as per the syllabus: Covalent bonding in carbon compounds. Versatile nature of carbon. Homologous series, Nomenclature of carbon compounds containing functional groups (halogens, alcohol, ketones, aldehydes, alkanes and alkynes), difference between saturated hydrocarbons and unsaturated hydrocarbons. Chemical properties of carbon compounds (combustion, oxidation, addition and substitution reaction). Ethanol and Ethanoic acid (only properties and uses), soaps and detergents.
This is first lecture of the Carbon and its compound which is the fourth chapter and is very important for SA-2 as it covers about 15-18 marks in exams. In this session you will learn about the Carbon and its properties. As you know carbon is an element and it has 4 valence electrons in its outermost shell, its valence electron are responsible for the entire change in the behavior and thus it forms maximum number of compounds. You will study here the terms covalency, catenation, tetravalency. The you will learn about the occurrence of Carbon. Sharing of electrons by Carbon. Then you will study the properties of hydrogen and how it forms compounds with hydrogen.Occurrence of allotropes of Carbon i.e.,Diamond, Graphite and Buckministerfulerene. You will study the properties of all three isotopes and difference among the three. You will also discuss the term Allotrophy, organic, Inorganic compound, saturated and

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Retrieved Text: The increasingly large number of organic compounds identified with each passing day, together with the fact that many of these compounds are isomers of other compounds, requires that a systematic nomenclature system be developed. Just as each distinct compound has a unique molecular structure which can be designated by a structural formula, each compound must be given a characteristic and unique name.
Such common names often have their origin in the history of the science and the natural sources of specific compounds, but the relationship of these names to each other is arbitrary, and no rational or systematic principles underly their assignments.
A rational nomenclature system should do at least two things. First, it should indicate how the carbon atoms of a given compound are bonded together in a characteristic lattice of chains and rings. Second, it should identify and locate any functional groups present in the compound. Since hydrogen is such a common component of organic compounds, its amount and locations can be assumed from the tetravalency of carbon, and need not be specified in most cases.
 A root or base indicating a major chain or ring of carbon atoms found in the molecular structure.
 A suffix or other element(s) designating functional groups that may be present in the compound.
 Names of substituent groups, other than hydrogen, that complete the molecular structure.
As an introduction to the IUPAC nomenclature system, we shall first consider compounds that have no specific functional groups. Such compounds are composed only of carbon and hydrogen atoms bonded together by sigma bonds (all carbons

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Retrieved Text: This page deals briefly with the combustion of alkanes and cycloalkanes. In fact, there is very little difference between the two.
Complete combustion (given sufficient oxygen) of any hydrocarbon produces carbon dioxide and water. It is quite important that you can write properly balanced equations for these reactions, because they often come up as a part of thermochemistry calculations. Some are easier than others. For example, with alkanes, the ones with an even number of carbon atoms are marginally harder than those with an odd number!
With butane (C4H10), you can again balance the carbons and hydrogens as you write the equation down.
Counting the oxygens leads to a slight problem - with 13 on the right-hand side. The simple trick is to allow yourself to have "six-and-a-half" O2 molecules on the left.
The hydrocarbons become harder to ignite as the molecules get bigger. This is because the bigger molecules don't vaporize so easily - the reaction is much better if the oxygen and the hydrocarbon are well mixed as gases. If the liquid is not very volatile, only those molecules on the surface can react with the oxygen. Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbors and turn to a gas.
Provided the combustion is complete, all the hydrocarbons will burn with a blue flame. However, combustion tends to be less complete as the number of carbon atoms in the molecules rises. That means that the bigger the hydrocarbon, the more likely you are to get a

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Retrieved Text: Covalent bond or Molecular bond or Homopolar bond : A chemical bond formed between two non-metallic elements by the mutual sharing of one or more electron pairs is called covalent bond.
Covalency : The number of electron pairs which an atom of an element mutually shares with another atom or atoms of the same or different elements, so as to acquire a stable configuration like noble gases, is called co valency.
Properties of covalent (molecular) compound : (i) They have low melting point and boiling point. (ii) They have low density, i.e., their density is generally less than that of water. (iii) They are gaseous or volatile liquids or soft solids. (iv) They are insoluble in water, but soluble in organic solvents. (v) They are generally bad conductors of electricity.
Diamond is the purest crystalline form of carbon which is the hardest naturally occurring substance.
Other pure crystalline forms of carbon are graphite and fullerenes. In Buckminster- fullerene, each molecule has 60 atoms arranged in hexagons and pentagons.
Organic Chemistry : The branch of chemistry dealing with carbon compounds other than carbon monoxide, carbon dioxide and carbonates is called organic chemistry.
Catenation : The property of carbon atoms to link with other carbon atoms or the atoms of other elements with single, double or triple covalent bonds, so as to form large number of compounds is called catenation.
Saturated organic compounds : Organic compounds in which all the four valencies of carbon atoms are satisfied by single covalent bonds, are called saturated organic compounds.
Unsaturated organic compounds : Organic compounds in which a double

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: Olefin content is an important factor in fuel production. But what exactly are olefins? In short, they’re an unsaturated hydrocarbon. Of course, there’s more to the story than that alone. Read on as we take a closer look at olefins – where they come from, what they’re made up of and why they’re important.
Olefin is a compound comprising hydrogen and carbon, with at least one pair of carbon atoms. Those atoms are linked by a double bond, which – along with the hydrogen and carbon content – makes them an unsaturated hydrocarbon.
Also known as alkene, olefins can vary in the number of double bonds per molecule, making them mono-olefins, diolefins, triolefins and so forth. They can also be categorised as either cyclic or acyclic. Cyclic olefins have a double bond between carbon atoms which makes up a closed ring of compounds. On the other hand, acyclic olefins form an open-chain group.
Where do olefins come from?
One of the earliest processes where olefins were produced came in the early 1900s through thermal cracking. This technique uses high temperatures and high pressure to break up large hydrocarbons into smaller compounds. They can also be produced by other forms of cracking, such as hydrocracking and fluid catalytic cracking.
Both petrol and diesel contain several different hydrocarbon molecules. Paraffins, olefins and aromatics account form most hydrocarbons in petrol, while diesel is mostly paraffins, aromatics and naphthenes.
Paraffins can improve the ignition quality of fuels, but can have low-termperature resistance. On the other hand, aromatics have high octane numbers – meaning the fuel can

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Retrieved Text: Any organic compound composed only of carbon and hydrogen.
Any organic compound composed only of carbon and hydrogen. Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.
Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.

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Retrieved Text: To describe the bonding in benzene and the way typical reactions of benzene differ from those of the alkenes.
Next we consider a class of hydrocarbons with molecular formulas like those of unsaturated hydrocarbons, but which, unlike the alkenes, do not readily undergo addition reactions. These compounds comprise a distinct class, called aromatic hydrocarbons, with unique structures and properties. We start with the simplest of these compounds. Benzene (C6H6) is of great commercial importance, but it also has noteworthy health effects.
The formula C6H6 seems to indicate that benzene has a high degree of unsaturation. (Hexane, the saturated hydrocarbon with six carbon atoms has the formula C6H14—eight more hydrogen atoms than benzene.) However, despite the seeming low level of saturation, benzene is rather unreactive. It does not, for example, react readily with bromine, which, is a test for unsaturation.

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Retrieved Text: Scientists may possibly have found clues to what seems to be the path to forming life's building blocks in space.
Published in Nature Astronomy journal the new study reveals that lab experiments carried out by scientists to retrace the chemical steps leading to the creation of complex hydrocarbons in space, showing pathways to forming 2-D carbon-based nanostructures in a mix of heated gases. Scientists say their findings could help explain the presence of pyrene, which is a chemical compound known as a polycyclic aromatic hydrocarbon, and similar compounds in some meteorites.
Scientists explain that Pyrene has a molecular structure composed of 16 carbon atoms and 10 hydrogen atoms. Researchers found that the same heated chemical processes that give rise to the formation of pyrene are also relevant to combustion processes in vehicle engines, for example, and the formation of soot particles.
The latest study builds on earlier work that analyzed hydrocarbons with smaller molecular rings that have also been observed in space, including in Saturn's moon Titan - namely benzene and naphthalene.
Pyrene belongs to a family known as polycyclic aromatic hydrocarbons, or PAHs, that are estimated to account for about 20 percent of all carbon in our galaxy. PAHs are organic molecules that are composed of a sequence of fused molecular rings. To explore how these rings develop in space, scientists work to synthesize these molecules and other surrounding molecules known to exist in space.
For this study, researchers explored the chemical reactions stemming from a combination of a complex hydrocarbon known as the 4-phenanthrenyl radical, which has a molecular

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Retrieved Text: Hydrocarbons containing at least three carbon atoms and non-aromatic carbon-to-hydrogen bonds are converted into hydrocarbons containing a new carbon-to-carbon linkage and having a higher carbon to hydrogen ratio by heating with an hydrogen-accepting olefine and a proportion of iodine (or hydrogen iodide, alkyl iodides or other compound which liberates iodine under the reaction conditions) of at least 0.05 mol. per mol. of hydrocarbon to be converted at at least 300 DEG C. to effect carbonto-hydrogen bond cleavage in the hydrocarbon feed and convert the olefine to paraffin. Conversions which may be effected are dehydrogenation of alkanes or aralkanes, e.g. isobutane to isobutene, n-butane to butenes and butadiene, ethyl benzene to styrene, o-methyl ethyl benzene to o-methyl styrene, and n-butyl benzene to 4 - phenyl - butadiene - 1,3; dehydrocoupling, e.g. propylene to diallyl, isobutene to dimethallyl, toluene to dibenzyl and stilbene; dehydrocyclization often with aromatization, e.g. n-hexane to benzene, n-heptane to toluene, n-octane to m-xylene and ethyl benzene, 2,5-dimethyl hexane to p-xylene, hexadiene-1,3 to benzene, hexane-1 to cyclohexene, o-diethylbenzene to naphthalene, o-methyl propyl benzene to naphthalene, n-butyl benzene to naphthalene, 2,3-diethyl naphthalene to anthracene, butylcyclohexane to naphthalene, and butylcyclopentane to indene; and dehydrogenation, often with aromatization of hydroaromatic hydrocarbons, e.g. cyclohexane to cyclohexene and benzene, and methylcyclohexane to toluene. In the case of acyclic hydrocarbons containing a quaternary carbon atom, dealkylation and/or isomerization may occur, e.g. 2,2,5-trimethylhexane gives p- and m-xylenes. The olefine used should be such that the sum of the standard free energy change for the hydrogenation of the olefine to the corresponding paraffin

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Retrieved Text: It’s well understood by physicists that stars are responsible for building most of the abundance of elements heavier than helium, through nuclear fusion. Recent observations from LIGO and optical counterparts of neutron star collisions indicate that these processes, and not supernovae, may be responsible for constructing certain elements such as gold and platinum.
But another considerable mystery is how complex chemistry occurs in outer space - how do these elemental building blocks meet and form complex hydrocarbons, like those that seem to be required for carbon-based life?
Now, new experiments have looked at conditions similar to those in outer space to assess the feasibility of processes to form a complex hydrocarbon molecule, pyrene. The study was an international collaboration between experimentalists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), astronomers from the University of Hawaii at Manoa, and theoretical chemists to understand the chemical reactions at Florida International University. The study was published March 5, in Nature Astronomy.
Hydrocarbons can include a vast array of different chemical compounds, due to the rich chemistry made possible by the hydrogenic bonding; molecular rings can form to provide a huge range of substances, many of which are used by biological organisms. Examples that have been detected in space include benzene and naphthalene. Pyrene is a slightly more complex molecule, consisting of 16 carbon atoms and ten hydrogen atoms; you can view it as four rings of benzene fused together. These polycylic aromatic hydrocarbons (PAHs) are considered possible precursors for the origin of life, and they are associated with the

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Retrieved Text: 1.3.10 compounds with same molecular formula but different structural formula.Due to different chain length, they have different physical properties (e.g. boiling point). Isomerism can occur in both alkanes and alkenes.For alkene, double bond position can be changed.We therefore can’t just say that C6H14 is simply hexane because there are more variations of C6H14 and each variation has its own name.
1.6.2 small molecules (monomers) join together to form one molecule as the only product.
Crude oil is a mixture of complex hydrocarbons with varying boiling points, depending on the number of carbon atoms and how they are arranged.
Fractional distillation uses this property to separate the hydrocarbons in crude oil.
Naphtha fraction is used for production of petrochemicals, such as medicines, plastics and synthetic fibres, aside from fuels.
When naphtha is treated, not only it becomes a better fuel, it also contain more aromatic hydrocarbons, alkene and cyclic hydrocarbons which are important for petrochemical industry.
Crude oil is mostly used as fuel, though some allocated for chemical feedstock.
hydrocarbons which the combining capacity of the carbon atoms is as fully used as possible in bonding with hydrogen atoms.
They only have single bond (–) only.
hydrocarbons which the combining capacity of the carbon atoms is not fully used, e.g. only 2 or 3 hydrogen are attached to a carbon atom.
usually indicated by double bond (=) or triple bond with another carbon atoms.
Alkanes burn in air to ALWAYS form carbon dioxide and water.
When there is insufficient oxygen, the product is ALWAYS carbon monoxide and unburnt carbon.
Example: Butane is commonly used camping gas. State the chemical equation

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Retrieved Text: How is crude oil refined? What are the products it produces? Where does Australia sit in its ability to process crude oil? Not just now but in the future? Please view our animated infographic by clicking on the image below or click here to get the answers.
Crude oil, in its raw natural form, must undergo refinement to make it useful for consumers. An oil refinery separates, converts, and purifies the components of crude oil into valuable petrochemicals. Many products, from propane to petrol to bitumen, can come from just one barrel of crude oil through refining. Australian oil refineries were constructed in the 1950s and 1960s. Together, they have a refining capacity of approximately half a million barrels per day. Let’s look at the fundamental processes in an oil refining setup, and learn more about Australia’s role in the global oil industry.
The composition of crude oil varies greatly between different natural sources. The two most important factors for profiling crude oil are its density and its sulfur content.
Oil that is less dense is referred to as “light,” whereas denser oil is classified as “heavy.” Oil with high sulfur content is called “sour,” as opposed to “sweet” oil which contains less sulfur.
As hevay oil requires more refining than light oil to yield useful products, light oil is valued higher than heavy oil. For the same reason, oil that is sweet is more valuable than oil that is sour.
Most of the crude oil found in Australia is premium crude; light and sweet.
*Total litres exceed the volume of one

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Retrieved Text: Why Does Cholesterol Lower Membrane Permeability?
What Are the Functional Groups in Cholesterol?
Cholesterol fills such important roles that your body makes its own supply rather than depending on dietary sources. Two of its jobs -- making bile acids and creating the outer coating of cells -- rely on chemical structures in the cholesterol molecule called functional groups. While cholesterol is not soluble in water, within the molecule, one type of functional group is water-soluble and another is insoluble. It turns out this dual characteristic plays an essential role.
Molecules are made from atoms, which sometimes combine to form a specific group of atoms. These are called functional groups because they’re responsible for precise tasks in your body. Functional groups also define unique characteristics of a molecule. Cholesterol has two types of functional groups. The first one, called a hydrocarbon functional group, consists of atoms of hydrogen and carbon. In cholesterol, the hydrocarbons connect to form two different shapes -- rings and chains. The second group, called a hydroxyl group, contains one atom each of hydrogen and oxygen.
Four hydrocarbon rings form the middle of the molecule. This functional group is the same one found in steroid hormones synthesized from cholesterol. A chain of hydrocarbons extends from one side of the nucleus, creating a hydrocarbon tail. One hydroxyl group is connected to the opposite side of the nucleus. There is one important difference between the groups: Hydroxyl groups are soluble in water, while hydrocarbons are not water-soluble. A molecule that has soluble and insoluble regions is called amphipathic. This amphipathic

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Retrieved Text: Having spent millions and millions of dollars surveying, exploring, appraising, designing, and developing a site, what do we have to show for it? This depends very much on the type of reservoir. ‘Oil and gas’ isn’t just one category (or even two), but covers a very broad range of mixtures defined by their chemical components.
From a commercial point of view, everything in oil or gas can be considered a hydrocarbon, an inert substance, or a contaminant. In the vast majority of reserves, hydrocarbons make up the vast majority of the mass and volume. This is just as well since they are the part we are most interested in. Hydrocarbons are, as the name implies, compounds made entirely of carbon and hydrogen, which come in an astonishing variety of shapes and sizes because of carbon atoms’ tendency to bond together in chains and rings.
The more common type of hydrocarbons is the aliphatic group, consisting of ‘chains’ and most types of ‘rings’. The simplest is methane, which is a gas has just one carbon atom and four carbon atoms. As we add carbon atoms in a line we get ethane, butane, propane, and pentane, all of which are gasses at room temperature; six carbon atoms make up the backbone of hexane, which is a liquid. These form a class of compounds called alkanes, which continue as you add more carbon atoms, forming increasingly viscous liquids and eventually solids (polythene is technically a very large alkane). Variants on the alkanes are the cycloalkanes, which are simple loops; alkenes and

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Retrieved Text: How Do You Calculate Number Of Isomers?
Where (n) is number of chiral carbon in compound?
Number of isomers are calculated using the no. Of carbon atoms in any compound. I think it is CnH4n-2 not valid for methane only.
To calculate isomers there are two methods: enumeration and counting. Finding the number of isomers in a given formula is called "counting." Finding the number of isomers, and all the individual elements of a formula is called "enumeration."
If you go to www.scctm.org./Awards/Ballard_Paper.pdf you will find a paper, which explains the calculation of numbers of isomers. Although, this article is chemistry specific, the first part of the article explains calculating the number of isomers.
On page 7 of the above paper you will find information about computerized calculations of isomers using enumeration. If you need to review isomers in general I suggest you go to www.chemistry-react.org/go/Tutorial/Tutorial_13027.html A site all about isomers. Just below the words, A creative look at Isomers, there is a green link. Click and you go to a new page Creative-Chemistry.org.uk Here you will find a simple definition of isomers, structural isomers, stereo isomers and more.
How Do You Calculate Product Of Numbers?
How Do I Calculate The Average Of Two Numbers?
How To Calculate Number Of Periods?
How Do You Calculate Percentage Increase When One Number Is 0?
How Do You Calculate 5% Of 8,648,459?
How To Do A Research Project?
Interview Question: Why Should I Hire You?
If y is inversely proportional to the square of x and y =1/9 when x =4, find y when x = 12?
I Need Some Multiple Choice Questions

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Retrieved Text: 23/03/2009 · 1. The problem statement, all variables and given/known data Name the structural isomers of C4H8Br2 and remember to number the carbon atoms …... All you have to do now is quickly draw out all the possible molecules that have five carbons and EITHER a ring or a double bond. You can't put both in there or you would be missing four carbons instead. Don't write out every C and H. Just use dots for the carbons, lines in between them for the bonds, and ignore the hydrogens. Shouldn't take much time at all.
23/03/2009 · 1. The problem statement, all variables and given/known data Name the structural isomers of C4H8Br2 and remember to number the carbon atoms … how to become a founder in monat 8/10/2015 · This video shows you how to draw the constitutional isomers of C4H10 such as butane and isobutane.
5/06/2008 · In the answers, it says there are only 2 structural isomers for butane. I thought it could be: butane, 1-methylpropane, ethylethane, or 1-2 methylethane ?

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Retrieved Text: Hydrocarbons and carbohydrates should not be confused. Hydrocarbons contain hydrogen and carbon only. Carbohydrates contain these two elements, but they also contain oxygen. In fact the "ate" suffix in chemistry implies oxygen. I'm sure you've heard of: carbonate (CO3), sulfate (SO4), phosphate (PO4), nitrate (NO3), and silicate (SiO4). These are not complete molecules - they are fragments, polyatomic anions to be precise, that are typically paired with metals to make salts or minerals, or with hydrogen to produce acids. Thus calcium carbonate, the principal component of limestone, or marble when compressed and heated over geologic time, is CaCO3. This "ate" nomenclature may help you remember that carbohydrates contain oxygen, and are a much more complicated molecule. In fact carbohydrates, along with proteins and fats, form the basis of food. These are the three macronutrients, as described earlier.
Since hydrocarbons contain only hydrogen and carbon, their structure is much simpler. In fact, the properties of a hydrocarbon molecule are determined, primarily, by the number of carbons. The simplest example has one carbon, surrounded by four hydrogens, and is called methane. It is a small, light, symmetric molecule, hence it is a gas. It does not liquify until -161C, or -258F. You've probably been out in weather that is subzero, but temperatures this cold are simply unimaginable.
The above representation is somewhat misleading, because it squashes the methane molecule onto the 2 dimensional page. Most molecules have a 3 dimensional structure. The carbon atom has four electrons in its outermost shell, four valence electrons, four bonds that must be satisfied.

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Retrieved Text: L'analyse détaillée des distillats moyens est une étape indispensable à la compréhension des mécanismes réactionnels et à la cinétique de certains procédés de raffinage comme l'hydrotraitement. Une nouvelle méthode associant, d'une part un couplage chromatographie en phase gazeuse/spectrométrie de masse (CG/SM) et, d'autre part une analyse quantitative par famille chimique par spectrométrie de masse a été développée. La chromatographie en phase gazeuse, réalisée sur une colonne apolaire, effectue la distillation des composés présents dans le gazole et la spectrométrie de masse quantifie les familles chimiques par intervalle de nombre d'atomes de carbone ou de point d'ébullition. Elle permet d'accéder ainsi à la répartition par nombre d'atomes de carbone de chaque famille chimique (alcanes, cycloalcanes, hydrocarbures aromatiques à un ou plusieurs noyaux, hydrocarbures aromatiques soufrés). Cette méthode a été validée et appliquée à une charge et à une recette d'hydrotraitement.
A detailed analysis of middle distillates is essential for understanding the reaction mechanism and for studying the kinetics of refining processes such hydrotreatment. In fact, when we see the complexity of saturated and aromatic hydrocarbon mixtures appearing in gas oil, we realize that it's necessary to have a very detailed analysis of those cuts to understand the mechanisms involved in refining processes and to be able to describe their kinetics. Each gas oil has a very different composition and therefore a specific reactivity. That is why we have tried to develop predictive kinetic models to avoid experimenting in pilot plants, which is very expensive. But, even if all the compounds of a gasoline (PI-200°C) have now been identified

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Retrieved Text: This course will help high school students in the AP program as well as college students taking introductory chemistry. Professor Hovasapian expertly breaks down concepts so that any student can understand. Every lesson also ends with four fully worked-out examples.
This biochemistry online course is geared towards college students who want to understand the complex chemical processes occurring in all living organisms. Our most popular course has helped a generation of college students ace the infamous weeder course of Organic Chemistry.
Starkey teaches with visual models, real world examples, lab walkthroughs, and fully worked out examples to make sure you understand what is going on. Everything is covered in a standard ochem course from Drawing Structures to Reactions, Transformation, and Synthesis. Each lesson contains all the steps to correctly setup and complete the experiment, as well as discussion of the theory, procedures, and calculations necessary for the lab report.
Our highest college level chemistry course, Physical Chemistry explains chemical systems using physics. Professor Hovasapian breaks down the complex theory into easy-to-understand ideas which he solidifies with several fully worked-out examples at the end of each lesson. Read on for more details about radiation chemistry! Introduces carbon structures and interactions between molecules. Basic vocabulary and ideas are introduced concerning alcohols and hydrocarbons.
Combustion of a hydrocarbon is also discussed briefly. Alkanes and alkenes are both hydrocarbons that follow the standard nomenclature procedures. Learn whether alkanes and alkenes are saturated or unsaturated, which is more reactive, and how to name a compound by looking at its structure in this lesson.
When aromatic compounds

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Retrieved Text: Carbon is termed to be an element of enormous importance to us in both elemental and combined form. Food, clothes, medicines, books, and many of the things are based on this element carbon. Also all the living structures are carbon based. Only 0.02% carbon is found in earth’s crust. Carbon is found in minerals like hydrogen carbonates, carbonates, coal and petroleum. 0.03% of carbon dioxide is present in the atmosphere. Though it is available in very small amount, its importance is very large.
Most of the carbon compounds are found to be poor conductors of electricity. Carbon compounds have covalent bonds between them. Covalent bond is a bond that is formed by sharing an electron pair between two atoms. Carbon compounds behave as poor conductors of electricity because of the presence of covalent bond between them. Carbon atoms form covalent bonds between themselves and with the atoms of other elements also.
Allotropy is defined as the property of some chemical elements to exist in two or more different forms. The two different allotropes of carbon are diamond and graphite. In diamond, each carbon atom is bonded to other four carbon atoms forming a rigid 3-dimensional structure while in the case of graphite each carbon atom is bonded to other three carbon atoms in the same plane giving a hexagonal array.Fullerene is also an allotrope of carbon containing clusters of 60 carbons joined together to form a sphere (similar to the football) and this allotrope is also called as buckminsterfullerene.
1 - Carbon has the distinctive capability to form bonds

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Retrieved Text: Here on warm, watery Earth, the molecules DNA and RNA serve as the blueprints of life, containing creatures’ genetic instruction manuals. An immense family of proteins carries out these instructions.
«The genetic molecules we have proposed could perform on ‘warm Titans’,» said paper lead author Steven Benner, a distinguished fellow at the Foundation for Applied Molecular Evolution, a private scientific research organization based in Alachua, Florida.
Bigger molecular cousins to Titan’s methane, such as the octane that helps fuel our vehicles, would also make for far more suitable solvents. Although no «warm Titans» close-in to their host stars have turned up so far in exoplanet exploration, Benner is hopeful there are worlds aplenty that fit the bill.
«Within our own solar system, we do not have a planet big enough, close enough to the Sun, and with the right temperature to support warm hydrocarbon oceans on its surface,» said Benner. «But each week, astronomers are discovering new solar systems other than our own.
» The new paper appeared in the March issue of the journal Astrobiology and was funded in part by the Exobiology & Evolutionary Biology element of the NASA Astrobiology Program.
DNA and RNA allow for a biological version of the axiom «the more things change, the more they stay the same.» Individual «letters,» or nucleobases, in the four-letter code of DNA and RNA can mutate without destroying the molecule’s overall form and function.
«This is the central point of the ‘polyelectrolyte theory of gene,’ which holds that any genetic biopolymer able to support Darwinian evolution operating in water must

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Input Text: Read the passage below and choose the right answer to the following question (choices are it will decrease or it will increase ):

Breast cancer is rare in teens but becomes more common as females get older.


Jay's risk of breast cancer is 10% at age 25. What will happen to her risk of breast cancer at age 50 it will decrease or it will increase?

Target Text: it will increase

#### Retrieved Documents ####

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Retrieved Text: Growing up in a home surrounded by Impressionist paintings, Mindy Goldfischer, MD, was taught by her parents to appreciate art. When looking at radiological studies in medical school, she found image interpretation similar to art interpretation, and she gravitated to the field of radiology. Dr. Goldfischer has served as the chief of breast imaging at Englewood Health for more than 25 years. In this interview, she discusses what women should know about breast cancer screening and the services of The Leslie Simon Breast Care and Cytodiagnosis Center at Englewood Health.
At what age should women begin breast cancer screening?
The American College of Radiology (ACR) recommends that women with an average risk of developing breast cancer begin annual screening mammography at age 40. Because younger women tend to have dense breast tissue, which can obscure masses, annual mammograms are important; sometimes a supplemental breast ultrasound is indicated. High-risk women — those who have a first-degree relative (mother, sister, daughter) with breast cancer or a BRCA gene mutation — should begin annual screening 10 years earlier, but not before the age of 25.
Is there an upper age limit for mammography?
The ACR recommends that women have an annual mammogram from ages 40 to 75. After the age of 75, women should consult their physician to determine whether they need additional screening.
Most women who develop breast cancer have no known risk factors. Only 5-10% of breast cancers occur in women with a genetic mutation, usually BRCA1 or BRCA2.
Women with a history of breast cancer are at increased risk for another breast

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Retrieved Text: This series explores medical conditions and procedures that can be devastating to the patients and families they affect — yet no one is talking about them. That is, until now. We will talk openly about these issues and dedicate these stories to the courageous individuals living with them as well as the healthcare providers and researchers committed to treating and seeking cures for these enigmatic diseases.
A planner by nature, Brittany Madonna’s life was right on track. By age 34, she had a happy marriage, two adorable children, and a fulfilling career. Everything was unfolding perfectly until May 2017, when a simple blood test revealed a ticking time bomb — the BRCA1 gene mutation. With that revelation, Brittany now knew she was at high risk for developing ovarian and breast cancer, which took her life-planning to a whole new level.
“My paternal grandmother died of ovarian cancer in her 50s — before I was even born,” says Brittany. “And 10 years ago, my aunt passed away from the same thing. We call it the ‘family curse.’” But far from being angered or immobilized by her family history, Brittany was empowered. She set out to learn everything she could about her risk factors and preventive options. And then she took action.
“I had blood drawn at my doctor’s office and she sent it to the lab. Three weeks later, Dr. Buck called me with the results. I tested positive for the BRCA1 mutation,” recalls Brittany. “Dr. Buck was surprised by the outcome. But I was stunned. My mind was a

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Retrieved Text: People with LCIS are considered to be at higher-than-average risk of developing invasive breast cancer over the next few decades of their lives. This is why doctors sometimes say that LCIS is a “marker” for increased breast cancer risk. The cancer can be either an invasive ductal carcinoma (cancer that starts in the duct and spreads beyond it) or an invasive lobular carcinoma (cancer that starts in the lobule and spreads beyond it). The invasive carcinoma may or may not develop from the original areas of LCIS that were found, and it can develop in either breast. Invasive ductal carcinoma is actually more common after LCIS than invasive lobular carcinoma is.
How greatly does having LCIS increase breast cancer risk? One estimate is that the lifetime risk of developing an invasive breast cancer is 30-40% for women with LCIS, versus a lifetime risk of 12.5% for the average woman. Another estimate suggests that an LCIS diagnosis increases breast cancer risk to 21% over the next 15 years.
If a woman with LCIS develops an invasive breast cancer, it doesn’t typically happen within a few years. Rather, it is more likely to happen over the long-term — in 10, 15, or 20 years or even beyond that. A woman with LCIS is considered to be at elevated risk for developing breast cancer for the rest of her life.
If you’ve been diagnosed with LCIS, learn what you can do to lower your risk of being diagnosed with an invasive breast cancer in the Lower Your Risk section.

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Retrieved Text: According to the American Cancer Society, about one in eight women in the United States will develop invasive breast cancer during her lifetime. Fortunately, death rates for breast cancer patients have been declining since about 1989, partly because of earlier detection through regular screenings and increased awareness.
“Finding breast cancer early reduces the risk of dying from the disease by 35 percent in women over 50 years of age,” notes radiologist Dr. Mimi Lin, director of mammography for the Washington Radiologists Medical Group.
The decision to offer breast cancer risk assessments resulted from community-needs surveys conducted in the communities served by Washington Hospital.
The Breast Cancer Risk Assessment Tool adopted by Washington Hospital was developed in 1989 as part of the Breast Cancer Detection and Demonstration Project. It is a statistical tool to estimate a patient's risk for breast cancer. The assessment is based on a statistical model known as the "Gail model," which is named after Dr. Mitchell Gail, Senior Investigator in the Biostatistics Branch of National Cancer Institute’s Division of Cancer Epidemiology and Genetics. The model uses a woman's own personal medical history, her own reproductive history and the history of breast cancer among her first-degree relatives (mother, sisters, daughters) to estimate her risk of developing invasive breast cancer over specific periods of time.
“The Breast Cancer Risk Assessment Tool is a well-established and valid statistical measure that is considered appropriate by most insurance providers, including Medicare,” Dr. Sharma notes. “The risk factors evaluated in the assessment tool are ones that highly correlate with increased risk for breast

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Retrieved Text: Embed from Getty ImagesBreast cancer is, without any doubt, women’s most feared cancer. In spite of increased awareness through women’s education, campaigns for its early detection and extensive research, some misconceptions persist and many issues are still a subject or debate, even among doctors and scientific organisations.
You are at increased risk of breast cancer if you have a family history, but of all breast cancers, only 5 to 10% are hereditary.
If you have one first-degree female relative (mother, sister or daughter) with breast cancer, then your risk is doubled; with two first-degree relatives, your risk of breast cancer is 5 times higher. If your affected relative is a male (yes, men do get breast cancer, but is very rare), your risk of getting breast cancer is higher. The same seems to be true for having a female relative with breast cancer from your paternal side (e.g. an aunt or your grandmother).
Most (but not all) hereditary breast cancers are caused by a defective gene passed from mother to child, the best known of which are BRCA1 and BRCA2. If you have a family history of breast cancer, you may discuss with your doctor whether you should be checked, what being positive means and what you can do about it. As a rough estimation, while an average woman has about 12% risk of developing breast cancer in her lifetime (that is, of 100 women, 12 will develop breast cancer at some point in their lives), a woman with a gene defect may have 45 to 80% risk (4

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Retrieved Text: Both women AND men can get breast cancer from inherited breast cancermutations.
Dr. Dharmen Patel was most recently Fellow at Westchester Medical Center and Dr. Lawrence Shapiro is Professor of Pediatrics at New York Medical College and Director, Regional Medical Genetics Center, Westchester Medical Center.
Not long ago, breast cancer was shrouded in mystery. Though doctors knew it affected the human body and had a number of fairly effective treatments, they knew little about its cause. The same could be said for the factors that affect risk. Now, however, thanks to recent advances in genetics, this is all changing, and quickly.
Today medical scientists can pinpoint mutations in individual genes which increase breast cancer risk. While these mutations do not account for all cases of breast cancer — there are other factors remaining to be explored — the presence of the mutations offers a more accurate picture of a person's risk for breast cancer. Some of these mutations are passed down through families and ethnic groups. For many women, this has important implications for monitoring, prevention and even treatment of breast and other cancers, such as ovarian cancer.
For example, let us look at the case of one real woman.
A 44-year-old woman, whom we will call Sarah, is asking her doctor for advice about whether or not to seek genetic counseling. With good reason — she has an extensive family history of breast and ovarian cancer. Her mother had been diagnosed with ovarian cancer at age 67. Her maternal grandmother reportedly had breast cancer in her 40's. Her maternal aunt

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Retrieved Text: A Blood Test for Breast Cancer Risk Led Jolie to Remove Her Breasts—Should You?
Last month, Angelina Jolie chose to announce to the world that she had undergone a double mastectomy and reconstruction to decrease her risk of breast cancer. Jolie had a family history of breast cancer, which led her to undergo a blood test for breast cancer risk that looks for genetic markers believed to indicate high risk.
Her doctors found that she had a mutation of the BRCA1 gene, and estimated her chance of getting breast cancer at 87 percent.
As Jolie explained in the opinion pages of the New York Times, her mother died from breast cancer at the age of 56 after a decade of fighting the disease. She didn’t want her children to lose her the same way.
Jolie, research shows, isn’t the only one opting to remove her breasts rather than take the risk.
Peggy Orenstein reported in New York Times Magazine results from a study in The Journal of Clinical Oncology: from 1998 to 2005 there has been a 188% jump among women given a diagnoses of D.C.I.S.—also known as “Stage Zero”—in just one breast who choose to have both breasts removed just in case.
D.C.I.S., which stands for ductal carcinoma in situ, means that there are abnormal cells found in the lining of the milk-producing ducts within the breast.
Unfortunately, there is no way to tell if those abnormal cells will turn into invasive cancer, so every case is treated as potentially life threatening.
One of the researchers Orenstein interviewed, Laura Esserman, likened this to

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Retrieved Text: Analysis of 102,927 women from the Breast Cancer Now Generations Study finds those who have smoked may be 14% more likely to develop breast cancer than never-smokers.
A major new prospective study funded by Breast Cancer Now has found that smoking is associated with an increased risk of breast cancer, particularly among those who began smoking during adolescence and those with a family history of the disease.
It has been thought for some time that smoking might increase breast cancer risk, with a number of plausible biological reasons being suggested due to the carcinogenic effects of tobacco smoke – but previous epidemiological studies have produced inconsistent evidence into the link between the two.
However, a new analysis of 102,927 women from the Breast Cancer Now Generations Study – one of the world’s largest prospective cohort studies into the causes of breast cancer, which is following more than 113,000 UK women for 40 years – found that smoking was associated with an increase in breast cancer risk.
The findings – published today in Breast Cancer Research – may also have particularly important implications for women already at an increased risk of breast cancer due to having a family history of the disease. The study found that female smokers with a family history of breast cancer were around 35% more likely to develop the disease than someone with a family history who had never smoked.
Scientists at The Institute of Cancer Research, London, established participants’ smoking history through questionnaires at their recruitment to the study and during follow-up, from 2003 onwards. They determined

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Retrieved Text: Is a teenage girl you are about at risk for breast cancer?
Caring Women’s Brochure: Is a teenage girl you are about at risk for breast cancer?
This brochure is written for mothers, caregivers and other caring women in the lives of girls in the 16 – 22 age range.
This pamphlet raises awareness about the link between lifestyle risk factors, including alcohol consumption among young women and the increased risk for breast cancer.
Caring Women’s Brochure is part of PAD program Hookup to Breast Cancer Prevention. Learn more or visit hookuptobreastcancerprevention.ca.
Support for Caring Women’s Brochure is gratefully acknowledged from the Canadian Breast Cancer Foundation – Ontario Region.
Is a teenage girl you care about at risk for breast cancer? Evidence says – she could be.
Eating: The risk of breast cancer is likely to increase with unhealthy eating habits.
Physical activity: The risk of breast cancer increases for girls and young women who do not exercise regularly.
Alcohol: The risk of breast cancer increases with every alcoholic drink consumed. All drinks carry the same risk – beer, wine, liquor.
Why are teenage girls at risk?
When girls are young, moms or caregivers often make sure they get healthy food and drinks and exercise. As they get older, teens start to make their own choices on what to eat, drink and do. Research shows that when girls enter their teens, they often adopt unhealthy eating habits, drink more alcohol, and become less physically active. These lifestyle patterns cluster at this age, and can become fixed for life. So what they do now can affect their breast

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Retrieved Text: October is breast cancer awareness month, therefore I wanted to shed light on Ontario’s breast screening program guidelines. Breast cancer is the most common cancer in women, and will affect many families – including mine. I am fortunate to say that my grandmother is a breast cancer survivor and now I use my voice and education to help educate women about what they can do about their risk of getting this disease.
Of course, I will also begin with diet and lifestyle – however, it is crucial to screen yourself or get it done annually to decrease your risk.
Mammograms are recommended every two years for women over the age of 50, who have average risk. You may need a health care provider referral or self-referral (this may happen by doing a self exam). Criteria include: not experiencing any acute breast symptoms, no personal history of breast cancer, no current breast implants and no screening mammogram in the last 11 months.
They received chest radiation before they were 30 years old, and at least 8 years before.
How often should screening happen?
For average risk women, screening happens every 2 years using a mammogram.
For high risk women, screening happens every year using a mammogram and breast MRI/ultrasound.
Self-screening should be done every month, no matter your age or risk.
For average risk women, screening stops at 74 years old.
For high risk women, screening stops at 69 years old.
Self breast exams should be done on a monthly basis, and be part of your annual physical exam. When you are performing them yourself, there are

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Retrieved Text: When Michele de Jager discovered a lump in her breast while taking a shower, she wasn’t too concerned. She was a healthy 35-year-old, and had no family history of cancer. Just to be sure, however, she made an appointment with her doctor. This appointment lead to a mammogram, breast ultrasound (sonogram) and eventually a needle biopsy that confirmed what Michele was beginning to fear. She had breast cancer, one of the most common cancers in South African women.
Michele decided that she was going to do what it would take to survive. That meant following her doctors’ instructions, taking care of herself and living her life as normally as possible – from going to work to taking her daughters (then 10 and 12) to school. Now, six years after her diagnosis, this 41-year-old credit manager at Old Mutual Healthcare is living proof that breast cancer can be beaten.
Michele and other survivors’ victories confirm current optimism about this illness. Thanks to early detection and medical advancements, the outlook for breast cancer patients is better than ever before.
After the initial shock of her diagnosis, Michele realised that she needed to learn all she could about breast cancer. "My surgeon explained the details pertaining to my case, but the day after my diagnosis I headed straight for Old Mutual Healthcare’s oncology department for information and advice. The more you know, the easier it is to look at the situation realistically," she says.
She learnt that although breast cancer is often thought of as a single entity, it really is a general

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Retrieved Text: Who Are More At Risk Of Getting Breast Cancer?
Home Women's Health Breast Cancer Who Are More At Risk Of Getting Breast Cancer?
There are lifestyle and genetic factors that increase the risk of breast cancer; however this is not to say that all those who are at risk will get the actual disease.
Gender of being a woman is the first risk factor. Breast cancer a hundred times more likely to affect women than men.
Age is the other factor. The older a woman gets, the higher her risk of breast cancer is.
Early menstruation, or getting one’s first period at or before the age of 11 years also marginally increases the risk.
Like early menstruation, late menopause also increases ones risk of developing breast cancer, because of a prolonged exposure to the female hormone estrogen.
Women who have had not had any children or those who have had their first child at age 30 and above are also more at risk.
Women having had a previous breast cancer are more likely to develop another separate cancer of the breast.
Those women who have undergone hormone replacement therapy (HRT) are also thought to be more at risk of breast cancer. Use of the birth control pill also increases exposure to hormones, and hence is also thought to increase breast cancer risk.
Race and ethnicity are also risk factors; white Caucasian women are slightly more likely to develop breast cancer than black women.
Dense breast tissue that contains more glandular tissue and less fatty tissue is also seen to up the risk.
Certain benign breast conditions also are

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Retrieved Text: That is a great question - and it is a question that researchers continue to ask... According to the National Cancer Institute, a woman’s risk of developing breast cancer depends on several factors, some of which are related to her natural hormones. Hormonal factors that increase the risk of breast cancer include conditions that may allow high levels of hormones to persist for long periods of time, such as beginning menstruation at an early age (before age 12), experiencing menopause at a late age (after age 55), having a first child after age 30, and not having children at all. One study found that that women who were current or recent users of birth control pills had a slightly elevated risk of developing breast cancer. Interestingly, this same study suggested that 10 or more years after women stopped using oral contraceptives, their risk of developing breast cancer returned to the same level as if they had never used birth control pills, regardless of family history of breast cancer, reproductive history, geographic area of residence, ethnic background, differences in study design, dose and type of hormone, or duration of use. However, another study indicated that current or former use of oral contraceptives did not significantly increase the risk of breast cancer. Overall, there is not currently any conclusive evidence about the link between oral contraceptives an breast cancer.

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Retrieved Text: I was sitting next to her as she told her story of being diagnosed with inflammatory breast cancer at the age of 27. It wasn't the first time that I had heard a young woman talk through diagnosis and treatment of aggressive breast cancer, but I had to fight back tears while listening to Charity speak. Our entire video production team was struggling not to cry. What was it about her situation that captured all of us? Was it hearing Charity talk about her initial doctor’s visit and being told that the lump in her breast was probably nothing? Or maybe it was hearing her say that the next time she saw a doctor about it was in the emergency room, when the cancer had eaten through her breast and she had to be hospitalized, receive several rounds of chemotherapy, and later have a non-skin sparing double mastectomy. It could have been the moments when she talked about coming to terms with infertility at such a young age. I’m not sure which part of Charity’s story drew us in, but I do know that the experience of hearing and capturing stories like hers was a powerful experience for me and the production team of the Bring Your Brave educational campaign.
The Centers for Disease Control and Prevention (CDC) launched the Bring Your Brave campaign in 2015 to provide information about breast cancer to women younger than age 45. Our campaign tells real stories about nine young women whose lives have been affected by breast cancer. These stories

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Retrieved Text: By Caitlin Lopez, M.D., and Susan Gazzillo, R.N., M.S.N.
We know for a fact that annual mammograms for women starting at age 40 absolutely save lives. But we also now know that for women at higher risk of breast cancer due to family history and other factors, an additional layer of screening – specifically annual MRI scans – can provide another life-saving measure of early detection. For women with known genetic mutations, those two annual screening tests should begin at age 30, according to a new recommendations issued this month from the American College of Radiology.
Women overall in the U.S. have a roughly 12 percent lifetime risk of getting breast cancer. That means that for every eight women in the U.S., one will be diagnosed with breast cancer during her lifetime. In an assessment based on family history, personal medical history and other variables, women are considered to be at high risk if their lifetime risk of breast cancer is 20 percent or greater.
So, what are those risk factors? Well, simply being a woman and getting older for starters. But it’s important to understand that the risk factors themselves do not cause breast cancer; they simply increase the chance it may develop. Having several risk factors for breast cancer does not mean you definitely will get breast cancer. Conversely, most of the women who develop breast cancer have no known risk factors aside from being female. That’s why it’s important that all women, regardless of their risk profile, remain vigilant and get screened annually.
To know whether or

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Retrieved Text: In the UK, women between 50 and 70 are invited for breast screening every three years as part of a national breast screening programme. At your appointment, you will have a test called a mammogram (a breast x-ray) to look for cancer that may be too small to see or feel. The sooner breast cancer is diagnosed, the more effective treatment is likely to be.
If you have any questions or concerns about breast screening you can call our free Helpline on 0808 800 6000.
Something that may look unusual on your mammogram may be entirely normal for you, and most women who are recalled for assessment will not have breast cancer. You may find it useful to read our information on being referred to a breast clinic.
Listen to a discussion with one of our nurses about breast screening.
What happens at a routine breast screening appointment?
Your mammogram will usually take place at a breast screening unit, but in some areas you'll be invited to a mobile unit. A female practitioner will take your mammogram. The clinic will let you know how you will get your results. Learn more about having a mammogram.
Who is invited for screening?
To be invited for screening you have to be registered with a GP (local doctor). The screening service takes the names from your GP’s list at regular set times and you’ll be sent an appointment to come for a mammogram. This may not happen the year you turn 50, but it will happen by the time you are 53.
Women under 50 are not

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Retrieved Text: Breast Cancer Res Treat. 2015 Feb;150(1):181-9. doi: 10.1007/s10549-015-3286-6. Epub 2015 Feb 13.
Mammographic breast density and breast cancer risk: interactions of percent density, absolute dense, and non-dense areas with breast cancer risk factors.
Yaghjyan L1, Colditz GA, Rosner B, Tamimi RM.
We investigated if associations of breast density and breast cancer differ according to the level of other known breast cancer risk factors, including body mass index (BMI), age at menarche, parity, age at first child's birth, age at menopause, alcohol consumption, a family history of breast cancer, a history of benign breast disease, and physical activity. This study included 1,044 postmenopausal incident breast cancer cases diagnosed within the Nurses' Health Study cohort and 1,794 matched controls. Percent breast density, absolute dense, and non-dense areas were measured from digitized film images with computerized techniques. Information on breast cancer risk factors was obtained prospectively from biennial questionnaires. Percent breast density was more strongly associated with breast cancer risk in current postmenopausal hormone users (≥50 vs. 10 %: OR 5.34, 95 % CI 3.36-8.49) as compared to women with past (OR 2.69, 95 % CI 1.32-5.49) or no hormone history (OR 2.57, 95 % CI 1.18-5.60, p-interaction = 0.03). Non-dense area was inversely associated with breast cancer risk in parous women, but not in women without children (p-interaction = 0.03). Associations of density with breast cancer risk did not differ by the levels of BMI, age at menarche, parity, age at first child's birth, age at menopause, alcohol consumption, a family history of breast cancer, a history of benign breast disease,

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Retrieved Text: 3 days ago. Property Insurance · Vehicle Insurance · Family Insurance. Breast cancer is the most commonly diagnosed cancer in women, but that. The risk of getting breast cancer increases with age, so as long as a woman is. Shepherd Insurance is honored to announce our most recent. 21, 22, 23, 24, 25, 26, 27.
Carolyn Gammon needs your help today! Curly Car’s Cancer Fund – My name is Carolyn Gammon and I live in South Wales, with.
May 23, 2018. That same CDC report concluded that the number of Americans age 18 to 64 with a high-deductible. In other words, they're opting for insurance that only covers them if. For serious conditions, like breast cancer, even short gaps between. into a pickup truck that was towing a car carrier near Worcester.
After that, child care is an expensive patchwork: in 23 states it costs more than in-state public-college. Anna had left S.
In California’s Central Valley, T.J. Cox tells voters that before Obamacare, his insurance refused to cover his wife. both of whom have had breast cancer. “For a dozen or so Democrats — most of the.
A risk factor is anything that affects your chance of getting a disease, such as breast cancer. But having a risk factor, or even many, does not mean that you are.
Oct 20, 2015. Kathleen was only 23 and the last thing she was thinking about was. it over with and get them taken out, while I was still on their insurance.
Support, information and resources for breast cancer patients from CancerCare.
I did have travel

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Retrieved Text: A risk factor is anything that increases the possibility that you will develop breast cancer. Risk factors are attributes that you cannot control, such as your age and family history, as well as those you can control – “lifestyle” factors like diet, alcohol consumption and weight. When talking about risk factors, we often hear about a family history of breast cancer – and while this is an important factor, it’s not the only one. In fact, it’s not even the most common one.
The most common risk factor? Well, being female, for starters. It seems obvious, because breast cancer is known as a “woman’s disease,” but men do get it. It’s rare, but about 1% of the 225,000 diagnoses of breast cancer a year are given to men. After that, age is the most common risk factor. Most cases of breast cancer are found in women over 50, and the average age of a diagnosis is 63.
Obviously, we can’t control some of these factors. Age and genetics are two things we can’t escape from. But environmental factors we can control. Alcohol is linked to a clear increase in breast cancer risk, as is obesity. The link to certain foods is less certain, but researchers agree diet plays a part. Most experts agree that significant health benefits result from eating a diet rich in fruits and vegetables and lower in fat and animal products, and more than just in terms of cancer risks. Take a good look at the foods you eat and what you can substitute –

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Retrieved Text: If your mother, sister, father or child has been diagnosed with breast or ovarian cancer, you have a higher risk of being diagnosed with breast cancer in the future. Your risk increases if your relative was diagnosed before the age of 50.
If you have been diagnosed with breast cancer in one breast, you have an increased risk of being diagnosed with breast cancer in the other breast in the future. Also, your risk increases if abnormal breast cells have been detected before (such as atypical hyperplasia, lobular carcinoma in situ (LCIS) or ductal carcinoma in situ (DCIS)).
Early menstruation (before age 12), late menopause (after 55), having your first child at an older age, or never having given birth can also increase your risk for breast cancer.
Having dense breast tissue can increase your risk for breast cancer and make lumps harder to detect. Be sure to ask your physician if you have dense breasts and what the implications of having dense breasts are.
A sedentary lifestyle with little physical activity can increase your risk for breast cancer.
A diet high in saturated fat and lacking fruits and vegetables can increase your risk for breast cancer.
Being overweight or obese can increase your risk for breast cancer. Your risk is increased if you have already gone through menopause.
Having radiation therapy to the chest before the age of 30 can increase your risk for breast cancer.
Taking combined hormone replacement therapy, as prescribed for menopause, can increase your risk for breast cancer and increases the risk that the cancer will be detected at

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Retrieved Text: The chances are that any woman feeling a lump in her breast goes into panic mode but not every lump is breast cancer. Most breast lumps are benign (not cancer) and cause few or no health problems. However, at age 40 your risk of developing breast cancer in the next ten years increases sharply.
Breast cancer develops when cells in the breast grow out of control. As the cancer cells grow, they can begin to push on or damage nearby organs, blood vessels, and nerves causing symptoms.
Breast cancer is the most commonly diagnosed cancer among African women and worldwide.
It is second only to cervical cancer as the leading cause of cancer death among women in Africa.
Rates of cancer have doubled in many African countries over the last 20 years.
Most women with Breast cancer in Africa seek medical attention in the late stages of the illness. Often, there’s not a lot that can be done at that point to save the patient.
Poor health awareness on the part of women, combined with the lack of early detection programs, create the huge problem of late diagnosis.
In Africa, there is limited access to timely and proper medical treatment for cancer in general.
What can increase your risk for Breast cancer?
A Breast cancer risk factor is something that makes a woman more likely to get breast cancer than other women. Nevertheless, having one or even many breast cancer risk factors doesn’t necessarily mean you’ll develop breast cancer. Many women who have breast cancer don’t have any risk factors other than simply being women.
A

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Retrieved Text: October can be a month of empowerment, reflection and fundraising for those who have been affected by breast cancer. "It takes everyone-both women and men alike -to help fight breast cancer".
"We are pleased to be able to support this worthy cause and help raise awareness of the impact this disease has on so many people every year", said company president Allan Raikes. You can look out for some of the signs and symptoms of breast cancer on their own.
The next stage was a CT scan to see if the cancer had spread to other parts of Ger's body. People still lack information yet they need this if they are to beat the deadly ailment. Fellows will spend one year developing a strong knowledge of all aspects of breast disease, breast medical oncology, and breast surgery.
Following the walk, the three organizations will host the "DREAM to Inspire and Tour for a Cure" brunch from 1 p.m.to 6 p.m.at Katch Brew and Grill - located at 31-19 Newtown Ave.in Astoria - to honor those who now are battling or have battled breast cancer.
He also says there are people who have genetic predisposition where cancers run in the family. However, very few cases of breast cancer are hereditary. However, there are certain factors that would put women in a higher risk category. Is she a teenager?
"Only 5 to 10 percent of breast cancer diagnoses are genetic", said Dr. Joyce Slingerland, director of the Braman Family Breast Cancer Institute at Sylvester Comprehensive Cancer Center at the University of Miami, where

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Retrieved Text: A research team from the Mayo Clinic has identified specific genes that go with an increased risk for developing triple-negative breast cancer, according to a new study published in the Journal of the National Cancer Institute.
While breast cancer is the most common cancer among women in the United States, not all breast cancers are the same. There are different types of breast cancer, which are determined by the specific cells in the breast that are affected, according to the American Cancer Society.
“Triple-negative breast cancer accounts for 15 percent of breast cancer in the Caucasian population and 35 percent in the African-American population," Dr. Fergus Couch, lead author of the study, said in a press release. "It is also associated with an increased recurrence risk and poor five-year survival rates relative to other breast cancers."
A woman faced with breast cancer, of course, hopes for a definitive test that can tell her what form of cancer she has, and the best steps to treat it. Right now, genetic testing for breast cancer looks mostly at the genetic changes that come from a person's parents and grandparents, and the increased risk of being genetically predisposed to some cancers.
But only 5 to 10 percent of breast cancers are inherited genetically, according to the American Cancer Society. Triple-negative breast cancer is one of the hardest types of breast cancer to treat because it moves so quickly that screening tests don’t often “catch it” before it becomes serious.
So, what exactly is triple-negative breast cancer?
This type of cancer means that the three most

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Retrieved Text: “I tell my patients to begin annual mammograms at age 40 and continue as long as they are in good health,” says Claire Edwards, MD, breast surgeon, The Reinsch Pierce Family Center for Breast Health, VHC Physician Group. As a woman ages, her risk of getting breast cancer increases. According to Susan G. Komen®, the median age for breast cancer diagnosis in the United States is 62. To catch breast cancer early, having mammograms on an annual basis is the safest, most cautious guideline to follow.
If there is a strong family history, you should begin mammogram screening 10 years before the age when breast cancer affected your youngest family member. That means if your paternal aunt was diagnosed at age 45, you should begin having mammograms at age 35. Ethnicity is also a factor in determining when to be screened. Because breast cancer can be more aggressive in African American women and women of Ashkenazi Jewish descent, they should have a breast cancer risk assessment at age 30, and be screened subsequently according to their individual risk.
Mammograms have changed significantly with the advent of 3D (three-dimensional) mammograms (also called tomosynthesis), which take multiple images of the breast to create a 3D picture. “I highly encourage all women to get a 3D mammogram. It allows us to detect tumors earlier at smaller sizes. Because it is more accurate than a standard 2D mammogram, there are fewer false positive readings and callbacks for repeat imaging,” says Dr. Mezban.
Having dense breast tissue makes it harder to detect cancer on

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Retrieved Text: Leslie Bernstein delayed her scientific career to raise a family and received her Ph.D. in biostatistics at age 42. She then pursued a career as a cancer epidemiologist and was the first to demonstrate that exercise lowers women’s breast cancer risk. Her research seeks to identify modifiable factors like exercise, body size, and hormone therapy use, which alter cancer risk. She has also documented how chemotherapy and hormonal therapy for breast cancer affect the development of subsequent cancers, stroke, and heart disease and how certain lifestyle habits extend survival after treatment is completed. With more than 450 publications in her 29-year career, Bernstein has won numerous national and international awards for her breast cancer research, particularly for showing how exercise lowers breast cancer risk, and for her advocacy for women in science and her creative mentoring. After spending 25 years at the University of Southern California where she held an endowed chair and served as medical school dean for faculty affairs and university vice provost for medical affairs, Bernstein has built the Division of Cancer Etiology at the City of Hope Comprehensive Cancer Center and is again dean for faculty affairs.

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Retrieved Text: In order to make mature decisions about breast cancer screenings, it is important to understand the risk factors of breast cancer. Keep in mind, however, that having a risk of breast cancer does not mean that you’re destined to develop it; most women with one or two breast cancer risk factors will never develop breast cancer at all.
Although men can get breast cancer, women are about a hundred times more likely to get it than men are. Besides the fact that women have more breast tissue, they also produce more of the hormones estrogen and progesterone, which can promote the growth of cancer. Age is a risk factor for breast cancer as well, with about two thirds of breast cancer patients being above the age of 54. White women are also more likely to develop breast cancer than most other nationalities, although cancer in African American women is more likely to be aggressive, caught at a later stage, and diagnosed at an earlier age.
Between 5% and 10% of breast cancer cases are believed to be hereditary cancer. The most common genetic cause of breast cancer is a mutation in the BRCA1 or BRCA2 genes. In normal cells, these genes code for the production of proteins that prevent cells from growing abnormally. In other words, they indirectly prevent cells from becoming cancerous. A mutated copy of these genes, however, does not work as well, which is why women and men who inherit these mutations are at a higher risk of developing breast cancer (as well as some

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Retrieved Text: Dr. Domchek: One of our questions is what type of screening options are available to a 25 year old woman who has just been found to have a BRCA1/2 mutation. And the key is that for 25 year old women, the major risk for them over the next 10 years of their life is their risk of breast cancer. Things like risk of ovarian cancer and other cancers don't tend to occur at that very young age. Our current guidelines are to start with a breast MRI once a year, between ages 25 and 30, at which point we add on a mammogram at a 6 month interval. And those are the major recommendations we have at that time. Of course women can choose to consider a preventative mastectomy, but the key is to get started on the breast MRIs.

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Retrieved Text: Outside of skin cancers, breast cancer is the most common cancer in American woman. Women have approximately a 12% chance of developing this cancer sometime in her life. There are more than 3 million breast cancer survivors in the U.S.
When cells in the breast begin to grow out of control due to changes in DNA, breast cancer can begin. Often from a tumor, these cells may be visible on imaging or felt as a lump in the breast. If the cells invade other tissues or spread to distant parts of the body, the tumor would be considered malignant. While men can get this cancer, it is most commonly found in women.
Breast cancer can originate in any part of the breast but is commonly found in the ducts and glands. It is important to note that not all breast cancers can be felt as a lump in the breast, which is why screening mammograms are so important. Any lump or change should be discussed with your healthcare provider.
Breast cancers can spread to other areas of the body through the lymphatic system or through the blood system. If cancer cells are found in lymph nodes, there is an increased risk the cancer may have spread to other organs and can affect the treatment plan. This is not a sure fact, as some women with cancer in their lymph nodes do not have metastases.
Finding breast cancer early can help improve the prognosis of the disease and allow for more successful treatment. Self exams are an important part of overall

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Retrieved Text: It was already known that obesity is associated with an increased risk of breast cancer. Now a new study presented at an American symposium on breast cancer suggests that diabetes in women after the age of 60 is also associated with an increased risk of this type of tumour. According to the study, up to four years after a diabetes diagnosis, women of any age had a 37 percent higher risk of developing breast cancer.
For this study, researchers looked at the medical records of more than 2,700 patients for up to 10 years before they developed breast cancer and compared their records with those of over 20,000 patients who never developed this type of tumour.
They concluded that obesity after age 60 increased breast cancer risk by 55 percent. This means that 15 obese women out of 100 would be diagnosed with breast cancer, versus fewer than 10 out of 100 women in the general population. The link between breast cancer and diabetes was maintained even when taking into account patients’ obesity and other criteria (such as blood cholesterol levels).
These finding will have to be verified by other analyses before they can be confirmed, but in the meantime they do provide further incentive for women of any age to adopt a healthy lifestyle. By doing so, they are reducing their risk of obesity, diabetes and breast cancer, not to mention heart disease.

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Retrieved Text: Breast cancer is the most common form of cancer in women who are pregnant or have recently given birth, occurring once in every 3,000 pregnancies. An estimated 30 percent of all breast cancer in young women is diagnosed within a few years after a woman has a baby.
Younger women usually don’t think about getting breast cancer because their risk is much lower than older women. However, about 11 percent of all new breast cancer cases in the US are detected in women under the age of 45. More importantly, when breast cancer is diagnosed at a young age (under the age of 40), it can be more aggressive and fast-growing.
Often, a breast cancer diagnosis is delayed in younger women because they don’t think it can happen to them and they ignore the warning signs – a breast lump, a harmless cyst or an unusual discharge, for example. By the time a lump in a younger woman’s breast can be felt, the cancer may be advanced. Also, younger women tend to have denser breasts, and diagnosing breast cancer is more difficult.
That is why knowing your personal risk factors and taking preventive steps are important no matter how old you are.
Young women with breast cancer face different challenges.
Can young women screen for breast cancer?
The American Cancer Society (ACS) recommends that all women age 20 and older conduct monthly breast self-examinations.
Know your breasts and how they look and feel.
Report any changes to your family physician.
Have an annual clinical breast exam beginning at the age of 20 (annual screening mammograms

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Input Text: Read the passage below and choose the right answer to the following question (choices are bigger or smaller ):

In bigger atoms, valence electrons are farther from the nucleus.


If valence electrons are close to an atom's nucleus, the atom is likely bigger or smaller?

Target Text: smaller

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Retrieved Text: As seen in the previous section on the octet rule, atoms tend to lose or gain electrons in order to attain a full valence shell and the stability a full valence shell imparts. Because electrons are negatively charged, an atom becomes positively or negatively charged as it loses or gains an electron, respectively. Any atom or group of atoms with a net charge (whether positive or negative) is called an ion. A positively charged ion is a cation while a negatively charged ion is an anion. In this section, we briefly look at some of the processes through which electrons are gained and lost in the formation of ions.
The process of gaining or losing an electron requires energy. There are two common ways to measure this energy change: ionization energy and electron affinity.
The ionization energy is the energy it takes to fully remove an electron from the atom. Ionization energy is a property that varies predictably across the periodic table. Group I and II elements with few electrons in their outer shell have very low ionization energies, while ionization energies increase dramatically moving right along the periodic table. The octet rule gives a straightforward (albeit simplified) explanation of this trend: elements with few valence electrons (those on the left of the periodic table) readily give them up in order to attain a full octet within their inner shells.
When several electrons are removed from an atom, the energy that it takes to remove the first electron is called the first ionization energy, the energy it takes to

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Retrieved Text: 3. Type of waves that pass through soft body tissues but stopped by bones.
5. Type of waves that cause sunburn.
6. Part of the spectrum our eyes are sensitive to.
8. The space around the nucleus of an atom where electrons are found.
9. Neutral particle found in the nucleus of an atom.
12. Number of protons in an atom's nucleus.
13. Forms of the same element with different numbers of neutrons.
14. The sum of protons and neutrons in an atom.
15. Last name of chemisty who gave us the law of definite proportions.
16. Greek philosopher who first coined the idea of the atom.
20. A way of illustrating valence electrons.
22. Last name of scientists who discovered electrons.
23. A testable prediction to explain an observation.
24. Last name of chemisty who gave us the law of conservation of matter.
25. Type of electrons in the outermost energy level of an atom.
26. Waves with the lowest frequencies of the spectrum.
1. Regions of space in which electrons can move about the nucleus.
2. The four basic elements of matter according to the ancient Greeks [no spaces between words].
4. A fact of nature that is observed so often it is accepted as truth.
7. Type of waves that travel at the speed of light through space.
10. Small, dense, positively charged central core of an atom.
11. Positively charged subatomic particle.
17. Last name of scientist who discovered the nucleus.
18. An explanation based on many tests.
19. Type of waves with highest frequency and shortest wavelength.
21. Type of wave energy given off by the human body and other warm objects.

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Retrieved Text: – An element is defined as a substance which cannot be decomposed into other substances. The smallest particle of an element which takes part in chemical reaction is known as atom.
– All matter is composed of atoms which are infinitesimally small.
from the stand point of electrical conductivity, as conductors, semiconductors or Insulators .To be conductor, the substance must contain some mobile electrons that can move freely between atoms. These free electrons come only from the valence (outer) orbit of the atom Conductivity depends on the number of electrons in the valence orbit.
“The energy level of an electron increases as its distance from the nucleus increases. Thus an electron in the second orbit possesses more energy than electron in the first orbit, electrons in the third orbit have higher energy than in the second orbit and so on. It follows, therefore, that electrons in the last orbit will possess very high energy. These high energy electrons are less bound to the nucleus and hence they are more mobile. It is the mobility of last orbit electrons that they acquire the property of combining with other atoms. Further due to this combining power of last orbit electrons of an atom they are called valence electrons”.
Atoms with fewer than four valence electrons are good conductors.
Atoms with more than four valence electrons are poor conductors.
Atoms with four valence electrons are semiconductors.
Normally, the atoms are electrically neutral, that is, the number of electrons and protons are the same, cancelling each other’s electrical force. Atoms “stay together’ because unlike charges attract each

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Retrieved Text: Electron dot structures, also called Lewis structures, are a graphical representation of the way electrons are distributed throughout a compound. Each element's chemical symbol is surrounded by lines, representing bonds, and dots, representing non-bonded electrons. When drawing an electron structure, your goal is to make each element's valence, or outer electron shell, as full as possible, without going over the maximum number of electrons for that shell.
Determine each element in the structure by looking at its chemical formula. For example, carbon dioxide's formula is CO2. Therefore it has one carbon atom and two oxygen atoms.
Look up each element on the Periodic Table. Note each group, or column number. This reflects how many valence electrons the element has. For instance, carbon is in group 4A and oxygen is in group 6A; therefore carbon has four valence electrons and oxygen has six.
Add the valence electrons of all the elements. This is the total number of electrons available for the dot structure. Since 4 + 6 + 6 = 16, there will be 16 electrons in carbon dioxide's Lewis structure.
Determine which element is the least electronegative, or has the weakest pull on the electrons, by looking on an electronegativity chart or by examining the element's position relative to the other elements on the Periodic Table. Elements generally increase in electronegativity from left to right and from bottom to top. Carbon is the least electronegative element in the compound, with a value of 2.5.
Place the least electronegative element in the center of the structure, then surround it with the other

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Retrieved Text: You will place electrons in the appropriate energy levels outside of an atom.
Explain that an atoms outermost electrons are responsible for an elements reactivity.
Identify the electron arrangement within atomic energy levels.
Explain that an electrons energy is related to its distance from the nucleus.
An atom has three subatomic particles: the proton, the neutron, and the electron. The proton has a positive charge, is located in the nucleus and is responsible for an atom's identity. The number of protons does not change in an element, and is equal to the atomic number on the periodic table. Neutrons are also located in the nucleus, but have no charge.
The electrons are located outside the nucleus, and have a negative charge. The electrons will arrange themselves into specific energy levels, starting with the level closest to the nucleus. Each energy level has a maximum number of electrons it can hold: two in the first, eight in the second, 18 in the third and 32 in the fourth. As the distance of the energy level from the nucleus increases, so does the energy the electrons contain.
The arrangement of the electrons in their energy levels is called the "electron configuration." In a neutral atom, the number of electrons will be the same as the atomic number, or number of protons. For learners to place the electrons in the appropriate energy level, they should identify the atomic number, and start placing the electrons in energy levels, the closest to the nucleus first. Once the energy level has its maximum number of electrons, they should

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Retrieved Text: As a homeschooling mom, I think hands on activities make learning science so much more interesting and fun. I also think they help children to understand science in a more concrete way. Things like atoms and molecules are pretty hard for a young child to comprehend without something tangible to relate to. In this post, and in a series of posts that will follow, I want to share with you some ideas for teaching elementary and middle school aged children about chemistry.
Let’s start with atoms and molecules.
Atoms are tiny tiny particles that make up all matter. You can’t see them - in fact, they are so tiny that millions and millions of them can fit in the point of the very sharpest pencil. But eveything around us is made of millions and millions of atoms - our bodies, our homes, our pets, the trees, even the air we breathe! To help make this concept more concrete, take a look through a magnifying glass at an image in a book or a picture printed from your computer. This will work best with a magnifying glass that magnifies at 4X or higher.
What do you see? Can you see that the picture is made from many many tiny dots? When you look at the picture with just your eyes, you don’t see the dots, but the picture is really just a whole lot of tiny dots of color put together. Atoms are like this - only even smaller!
This is a fun activity for a group of children. You build

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Retrieved Text: the smallest unit of an element that has all of the properties of the element; basic building block of matter.
the number of protons and neutrons in the nucleus of one atom of the element.
the number of protons contained in each nucleus of its atoms of the element.
a horizontal row (left to right) in the periodic table.
a vertical column (up and down) on the periodic table.
a chart that organizes information about all of the known elements according to their atomic number.
describes how likely an element is to form bonds with other elements.
group 1 metals on the periodic table that contain 1 valence electron and lose their valence electrons the most easily, making them the most reactive metals.
group 1 metals on the periodic table that contain 2 valence electrons and are the second most reactive metals.
group 3-­12 on the periodic table. They have varying valence electrons and do not follow the normal trends of the other metals. They form brightly colored compounds and ions in solution.
group 17 nonmetals on the periodic table that contain 7 valence electrons. They only need to gain 1 valence electron to have a stable octet. They gain valence electrons the most readily, making them the most reactive nonmetals.
group 18 elements on the periodic table that contain 8 valence electrons (He has 2) and a full valence shell making them very stable and inert.
an element that has some properties of a metal and some properties of a nonmetal. The metalloids are found on the boron staircase, there are 7 metalloids: B, Si, Ge, As,

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Retrieved Text: According to Bohr’s atomic model, the electrons revolving around the nucleus are governed by a definite path and hence have a definite energy level so the electrons in an atom have well-defined energy levels.
When the atoms are brought close to each other, they begin to influence each other due to mutual interaction between them. This mutual interaction is more in case of outer shell than the inner shells.
If we take silicon as an element which is a semi-conduct with electronic configuration of 152 252 2P6 352 3P2. Since the crystal contains at least 1023 atoms per unit volume so there may be at least 1023 sub-levels which are created. These sublevels lie very close to each other and hence they are known as the energy band.
When separation is d1, the electrons in the outer-most shell of one atom do not interact with the electrons in the atoms the other due to large separation so, at this stage, each atom has its own specified energy level.
When separation is d2, the inter-atomic separation is less, so the electrons in the outermost shell start interacting with another due to which the modification of levels start (3s and 3p) levels, but still at this stage, energy gap occurs.
When separation is d3, inter-atomic separation reduces further and the independent 3s and 3p levels disappear. They are now distributed in a continuous manner, hence forming an energy band.
When separation is r, the atoms are at there actual inter-atomic separation due to which the energy band splits up into two levels with a

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Retrieved Text: An atom is one of the most basic units of matter in the known universe. Of course, you'll learn that far smaller components exist as you move forward through the physical sciences, but for the purposes of basic chemistry and physics, the atom--along with the protons and neutrons that make up its nucleus, and the electrons that orbit it like planets around the sun--is as basic as you'll need to get. If you want to make a model of a neon atom, you should keep in mind that it has 10 electrons.
Spray paint your foam balls to differentiate what they represent. Separate them into three groups: the large foam ball, two of the small ones, and the remaining eight. Lay each group on a different piece of newspaper (to protect the surface) and spray each group a different color, making sure your room is well ventilated. The large ball represents the atom's central nucleus, while the first two small balls represent its inner two electrons. The other eight balls represent its outer, or valance, electrons. Allow the balls at least two hours to dry before handling them.
Label the nucleus (large foam ball) using a black, permanent marker. Write neon's symbol "Ne" on it, as well as "P: 10" and "N: 10" to indicate the respective numbers of protons and neutrons.
Snip a piece of craft wire long enough to form a ring outside the nucleus and thread it through the two designated inner electrons (small foam balls). Attach each of the electrons to the nucleus using a

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Retrieved Text: Gram atomic mass & Molar mass.
First recorded evidence that atoms existed.
Dalton’s theory was based on the premise that the atoms of different elements could be distinguished by differences in their weights.
o The indivisibility of an atom was proved wrong , for, an atom can be further subdivided into protons, neutrons and electrons. o The atoms of same element are similar in all respects , but isotopes of same element have different mass.
An electron is a negatively charged component of an atom which exists outside the nucleus. Each electron carries one unit of negative charge and has a very small mass as compared with that of a neutron or proton.
Since the ray was attracted to a positive electric plate placed over the cathode ray tube (beam deflected toward the positive plate) he determined that the ray must be composed of negatively charged particles.
E. Goldstein in 1886 discovered the presence of new radiations in a gas discharge and called them canal rays. These rays were positively charged radiations which ultimately led to the discovery of another sub-atomic particle.
Canal Rays: The positively charged radiation produced in the discharge tube at low pressure and high voltage are called canal rays.
Q.1 What was the model of an atom proposed by Thomson? Q.2 What is the nature of charge on electrons?
the gold foil without getting deflected. empty.
completely rebound on hitting the gold compared to the total size.
Limitation: In Rutherford’s atomic model , Nucleus & electrons are held together by electrostatic force of attraction which would lead to the fusion between them. This

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Retrieved Text: The History of the Atom Timeline: 400 BC Scientist: Democritus (Greek Philosopher) Democritus was a Greek philosopher who was Each atom (of an element) is different in structure from other atoms (of other elements) An atom can be divided in smaller subatomic particles: Protons, Electrons and Neutrons The nucleus is the centre of an atom. It contains protons and neutrons. Electrons orbit... History of the Atom – Worksheet/Review sheet Name: Answer Key Period:-1. State 2 similarities between Dalton’s and the Modern Day model of the atom.
For example, water is a compound made up of 2 atoms of hydrogen and 1 atom of oxygen (a ratio of 2:1). Three atoms of hydrogen and 2 atoms of oxygen cannot combine to make water. Three atoms of hydrogen and 2 atoms of oxygen cannot combine to make water.... Calculated that the atom consisted mostly of empty space through which electrons move and also concluded that there was a tiny, dense region "the nucleus" centrally located within the atom that contained all of an atom's positive charge and virtually all of its mass.
Historical Development of Atomic Theory: Aristotle to Rutherford1. Democritus and Aristotle in 400 B.C.2. Aristotle: matter can be divided into smaller andsmaller particles.3. Democritus: the atom is the smallest unit.4. Aristotle’s theory was most popular.

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Retrieved Text: Questions and Answers - How do I read an electron configuration table?
Are you making a model of an atom and need to know how to place the electrons around the nucleus? If so, you will need to know how to read an element's electron configuration table. Follow these easy directions to learn how!
What is an electron configuration table?
The first number is the energy level. We can tell right away that an atom of gold contains 6 energy levels.
The lowercase letter is the sub-shell. The sub-shells are named s, p, d and f. The number of available sub-shells increases as the energy level increases. For example, the first energy level only contains an s sub-shell while the second energy level contains both an s sub-shell and a p sub-shell.
The number in superscript is the number of electrons in a sub-shell. Each sub-shell can hold only a certain number of electrons. The s sub-shell can hold no more than 2 electrons, the p sub-shell can hold 6, the d sub-shell can hold 10 and the f sub-shell can hold as many as 14.
How many energy levels does an atom have?
How many electrons are in each energy level?
How many electrons are in an atom's outer energy level?
Video - How to Draw an Atom!

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Retrieved Text: Molecular polarity occurs when atoms with different electronegativity rates combine in a fashion that results in an unsymmetrical distribution of electrical charge. Since all atoms have a certain amount of electronegativity, all molecules are said to be somewhat dipole. However, when a molecule possesses a symmetrical structure, the charges cancel each other out, thus resulting in a non-polar molecule. The same thing happens when all the atoms in a molecule contain the same electronegativity.
Determine each atom's electronegativity by using a periodic table of elements. If all the atoms have the same electronegativity, then the molecule is by default non-polar. Given the molecule CH4, Carbon (C) has an electronegativity of 2.5 and Hydrogen (H) has one of 2.1. Given the molecule NH3, Nitrogen (N) has an electronegativity of 3.0. However, given the molecule NCl3, Nitrogen and Chlorine both have the same electronegativity of 3.0, so the molecule is non-polar.
Draw the molecule using the Lewis dot diagram method. Count the number of valence electrons each atom contains. Arrange the atoms so that the one with the greatest electronegativity is in the center. Connect the atoms with single electron bonds and remove these electrons from the valence count. Position pairs of electrons around the outer atoms until you achieve an octet, and then remove these electrons from the count. Place any remaining electrons around the atom in the center.
Determine the molecule's polarity by inspecting its shape for symmetry. Given the example, the molecule CH4 has a tetrahedral shape that is symmetric. Thus, it is non-polar. The molecule NCl3 has

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Retrieved Text: Home › Kilted Suds ~ The Dirty Truth › What Are Free Radicals?
Usually when people ask me how I make my soap, my first response is "Very Carefully!" The truth of this process is actually quite simple, it's a lot of chemistry, a lot of formulas, a lot of trial and error, and a lot of practice. Why am I talking about chemistry? Simple, free radicals are all about chemistry too!
Let's put this in simpler terms: a free radical is an atom (or group of atoms) that has an unpaired electron and is therefore unstable and highly reactive. To fully understand what this means, you must have a basic knowledge of chemistry. High school chemistry (Ugh!) taught us that our bodies are all composed of a myriad of different cells, each consisting of multiple atoms and/or elements which are joined by chemical bonds. Each atom consists of a nucleus, neutrons, protons and electrons, protons being positive, electrons being negative. The number of protons in the atom's nucleus directly determines how many electrons surround the atom. The electrons are the part we are focused on. Electrons are responsible for bonding one atom to another to create molecules. Electrons orbit an atom in "shells". Each shell can hold a certain number of electrons before it is considered full and the next shell begins to fill. The first shell holds 2 electrons, the second holds eight, and so on.
It is the number of electrons in an atom's outermost shell that determines its chemical behavior. Atoms by nature want to

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Retrieved Text: When an electron is free to assume higher energy states around an atom's nucleus (due to its placement in a particular "shell"), it may be free to break away from the atom and comprise part of an electric current through the substance. If the quantum limitations imposed on an electron deny it this freedom, however, the electron is considered to be "bound" and cannot break away (at least not easily) to constitute a current. The former scenario is typical of conducting materials, while the latter is typical of insulating materials.
Some textbooks will tell you that an element's conductivity or nonconductivity is exclusively determined by the number of electrons residing in the atoms' outer "shell" (called the valence shell), but this is an oversimplification, as any examination of conductivity versus valence electrons in a table of elements will confirm. The true complexity of the situation is further revealed when the conductivity of molecules (collections of atoms bound to one another by electron activity) is considered.
A good example of this is the element carbon, which comprises materials of vastly differing conductivity: graphite and diamond. Graphite is a fair conductor of electricity, while diamond is practically an insulator (stranger yet, it is technically classified as a semiconductor, which in its pure form acts as an insulator, but can conduct under high temperatures and/or the influence of impurities). Both graphite and diamond are composed of the exact same types of atoms: carbon, with 6 protons, 6 neutrons and 6 electrons each. The fundamental difference between graphite and diamond being that

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Retrieved Text: Electron dot diagrams, sometimes called Lewis dot diagrams, were first used by Gilbert N. Lewis in 1916. These diagrams are used as a shorthand notation to show the number of valence electrons in an atom. More complicated versions can be used to show the bond between different atoms in a molecule.
Write the symbol of the atom you are drawing the electron dot diagram for in the middle of your paper. This symbol represents the nucleus of the atom and each of the four sides represents an orbital.
Locate the element you are drawing an electron dot diagram for on the periodic table of elements. Find the number of electrons in one atom of the element. The number of electrons is the same as the element's atomic number.
Find the number of valence electrons by subtracting the number of electrons in each level from the total number of electrons. There are two electrons in the first level and eight in the second, third and fourth levels. The diagram will represent only the outermost level of the electron field. Take the number of electrons and subtract the number of electrons in each level until you come to a level that is not entirely full. For the noble gases, the last level will be full, with no electrons left over, and this is the level you will draw.
Place the first two dots on the right side of the element symbol. This side is referred to as the s orbital.
Place the remaining dots in a counterclockwise fashion around the edges of the

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Retrieved Text: An atom is the smallest particle of matter that can combine chemically with another atom or molecule. It has a nucleus, composed of protons and neutrons, around which electrons orbit.
The electron carries a charge equal to the proton but opposite in charge (-e).
An atom has as many protons as electrons. The total charge is zero which is why matter is usually neutral.
In some cases, with the help of an external energy input, an atom can lose or gain one or more electrons. This is the phenomenon of ionization.
Example: An atom of sodium (Na) has 11 protons and 11 electrons. If it loses an electron, it then has 11 protons but only 10 electrons. A positive charge +e is no longer balanced and the resulting sodium ion is positively charged. The sodium ion, Na+, indicates that it carries a charge +e.
A molecule is an assembly of atoms that share electrons to achieve greater stability.
Click on one of the four active zones to start the animation.
To know the structure of an atom and a molecule.
To define an electrical charge.
To understand the phenomenon of the ionization of an atom.
To know the difference between a valence electron and a free electron.
To recognize two types of atomic bonds.

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Retrieved Text: Number of protons present in nucleus of atom of an element is known as atomic number.
Mass number is also known as atomic mass. Atomic number or mass number is equal to number of protons and neutrons in atom.
Atoms of same elements which have same atomic number but different mass number is called isotopes.
example : Protium, Deutrium, Tritium are isotopes of hydrogen.
Atoms of different elements which have similar atomic mass and different atomic number are called isobars.
In 1921, Bohr and Bury gives some laws for distribution of electrons in various orbits, which are called as Bohr-Bury Scheme.
1. Maximum number of electron in any shell should be 2n2 , where n is serial number of shell.
2. Maximum number of electron that exist in outermost shell or orbit of any atom is eight while maximum number is eighteen for penultimate shell.
3. According to this law, it is not necessary that another shell is formed after completion of 1st shell. A new shell is formed as number of electrons reaches eight in any orbit or shell.
Outermost incomplete shell of any atom is known as Valence Shell and electron present in incomplete outermost shell are known as Valence Electrons , which participate in formation of bond.

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Retrieved Text: principle that relates to electron energies.
separation for two atoms or ions.
separation and the bonding energy.
hydrogen, and van der Waals bonds.
protons and neutrons within the nucleus.
atomic masses, which are called isotopes.
 Electrons are assumed to revolve around the atomic nucleus in discrete orbitals, and the position of any particular electron is more or less well defined in terms of its orbital.
 Another important quantum-mechanical principle stipulates that the energies of electrons are quantized; that is, electrons are permitted to have only specific values of energy. An electron may change energy, but in doing so it must make a quantum jump either to an allowed higher energy (with absorption of energy) or to a lower energy (with emission of energy). Often, it is convenient to think of these allowed electron energies as being associated with energy levels or states. These states do not vary continuously with energy; that is, adjacent states are separated by finite energies.
- values of energy that are permitted for electrons.
 Bohr model was eventually found to have some significant limitations because of its inability to explain several phenomena involving electrons. A resolution was reached with a wave- mechanical model, in which the electron is considered to exhibit both wavelike and particle-like characteristics. With this model, an electron is no longer treated as a particle moving in a discrete orbital; but rather, position is considered to be the probability of an electron’s being at various locations around the nucleus. In other words, position is described by a probability distribution or electron cloud.
 Using wave mechanics,

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Retrieved Text: This chapter lays the foundation for your understanding of electronics. This unit introduces you to the fundamental concepts, terms, and units of measures common to all electronics technology. The material presented forms the basis for all subsequent studies in electronics. The information here in chapter two is very foundational to your understanding of electronics.
First of all, we're going to look at atomic structure. All matter is composed of increasingly smaller building blocks. Those building blocks are and there's a mention here of the building blocks of matter. I'm going to let you read through the first few here. If you want to press your pause button and stop and read through those, please go ahead. I'm going to pick up on down here at electrons. Electrons, negatively charged particle orbiting the nucleus of all atoms. That's what an electron is. A proton, positively charged particle in the nucleus of all atoms. A neutron, atomic particle having no charge located in the nucleus of an atom.
Below is a hydrogen atom. Atoms can be viewed as a miniature planetary system, similar in concept to our solar system. Here we have a single hydrogen atom and here is a large one. You get the idea here of a miniature planetary system. Each atom has a dense nucleus, which contains the protons and the neutrons. This is this area right here. Electrons orbit the nucleus of an atom. Notice here the electrons orbit the nucleus of an atom and an electron has a minute mass compared to the nucleus. A

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Retrieved Text: Periodic table[ edit ] Electron configuration table The form of the periodic table is closely related to the electron configuration of the atoms of the elements. Phosphorus, for instance, is in the third period.
Pauli-Exclusion Principle Wolfgang Pauli postulated that each electron can be described with a unique set of four quantum numbers. The electron configuration can be visualized as the core electronsequivalent to the noble gas of the preceding periodand the valence electrons: It is possible to predict most of the exceptions by Hartree—Fock calculations,  which are an approximate method for taking account of the effect of the other electrons on orbital energies.
Nitrogen, for example, has 3 electrons occupying the 2p orbital.
In bulk materials, this idea helps explain the peculiar properties of lasers and semiconductors. That is, we follow the three important rules: For atoms, the notation consists of a sequence of atomic subshell labels e.
It may be stated as: However, the energy of an electron "in" an atomic orbital depends on the energies of all the other electrons of the atom or ion, or molecule, etc. Hund's Rule Hund's Rule states that when electrons occupy degenerate orbitals i.
The electronic configuration for Cl- can, therefore, be designated as 1s22s22p63s23p6. The fact that the Aufbau principle is based on an approximation can be seen from the fact that there Atom and electron configuration an almost-fixed filling order at all, that, within a given shell, the s-orbital is always filled before the p-orbitals.
If that were the case, the 3d-orbital would have the same energy as the 3p-orbital,

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Retrieved Text: esting relationship that exists between the electromotive series and the periodic table. ... so far from the nucleus by the fifty-four other planetary electrons of the.
Modern text-books of first-year chemistry do not emphasize an interesting relationship that exists between the electromotive series and the periodic table. In fact one of the most widely used texts in first-year college chemistry lists among the defects of the periodic system the absence of any relationship between these two important generalizations of the science. It is true the relation that may be derived from the order in which the elements stand in the two tables is limited, but it is sufficient to furnish a striking example of how our modern conceptions of the structure of atoms enable us to obtain a clearer insight into the mechanism of chemical reactions. In following our present-day practice of placing emphasis upon interpretations based on atomic structure the anthor has found this illustration very enlightening to students of first-year chemistry. Reference to a periodic table and to a table of the order of activity of the metals will show that in the alkali family the heaviest metal is the most active, the next heaviest is second in order of activity, and that this relation holds throughout this family. Immediately below lithium, the lightest and least active metal of the alkalies, we find in the electromotive series the following for the order of decreasing activity of the alkaline earth family: barium, strontium, calcium, and magnesium; turning to the periodic table we find this to he

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Retrieved Text: UNDERNEATH ALL REALITY is broiling and industrious machinery. An atom is not a static structure ; it is a nano-machine. Everything within it—electrons, protons, neutrons, quanta—is moving and interdependent. Holding atomic machines together while the parts move about at thousands of miles per hour are strong and weak forces in the nucleus, and electromagnetic forces between electrons in their shells and the nucleus.
An atom has plenty to occupy it just going about its business being what it is. It is not thinking about becoming something else unless it is tinkered with. If the nucleus is bombarded with radiation it may start to decay (the entire nuclear industry is based upon such nuclear changes). If electrons are added or taken away, the atom's resulting imbalance will cause it to seek out ways to restore balance by combining with other atoms that may have too many or too few electrons (the entire chemical industry is based upon this). But such things are just normal social behavior of atom machines and are what they must do to keep running and be happy. We cannot get overly enthusiastic, implying evolution, and construe from this behavior that an atom wants to become part of a novel, painting, computer, or amoeba.
The same machine principles apply to proteins, nucleic acids, lipids, organelles, cells, and organisms. They are all machines with trillions of moving parts. Their goal is to stay running and keep their parts together. Homeostasis is their desire, not transmutation (evolution). A protein machine does not want to become a muscle machine,

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Retrieved Text: Semiconductors are utilized widely in electric circuits. As its name signifies, a semiconductor is a component which carries out electric power, but only partially. The conductivity of a semiconductor is someplace in between that of an insulator, that has basically no conductivity, and a conductor, that has basically complete conductivity. Many semiconductors are crystals made from specific components, many generally silicon.
To comprehend how semiconductors function, you should initially comprehend a little about how electrons are arranged in an atom. The electrons in an atom are arranged in layers. These layers are known as shells. The outer shell is known as the valence shell.
The electrons within this shell are the ones which form bonds with surrounding atoms. This type of bonds are known covalent bonds. Many conductors have only one electron in the valence shell. Semiconductors, however, generally have 4 electrons in their valence shell.
it is feasible for all the valence electrons to connect with valence electrons coming from other atoms if all the surrounding atoms are of the exact same type. The atoms organize on their own into structures known crystals while that occurs. Semiconductors are produced of such crystals, generally silicon crystals.
Right here, each circle stands for a silicon atom, and the lines in between the atoms stand for the shared electrons. Each of the 4 valence electrons in each silicon atom is provided one surrounding silicon atom. Hence, every silicon atom is bound with 4 other silicon atoms.
Pure silicon crystals aren’t all that effective digitally. If you present little quantities of other elements into

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Retrieved Text: Covalent bonds are chemical bonds that are formed by sharing valence electrons between adjacent atoms. This type of bonding is mostly seen in interactions of non-metals. Covalent bonds allow elements the ability to form multiple bonds with other molecules and atoms - a fundamental necessity for the creation of macromolecules. In the covalent bond, as the distance between the nuclei decreases, each nucleus starts to attract the other atom's electron, which lowers the potential energy of the system. Anyway, when the attraction increases, the repulsions between the nuclei and between the electrons increase as well. In covalent bonding, each atom achieves a full outer (valence) level of electrons. Each atom in a covalent bond counts the shared electrons as belonging entirely to itself. Most covalent substances have low electrical conductivity because electrons are localized and ions are absent. Overall, the atoms in a covalent bond vibrate, and the energy of these vibrations can be studied with the IR spectroscopy.
A general rule to follow when looking at covalent bonding is the octet rule, also known as the noble gas configuration. An atom participating in covalent bonding must (with few exceptions) follow the octet rule, which states that an atom must have eight electrons around it. These electrons can be shared or unshared. The two atoms do not need to share their electrons equally; an electron pair can be donated from one atom instead of each atom donating one electron. A periodic table can be used to determine the number of valence electrons an atom. The general rule

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Retrieved Text: The Atomic Age. The Rutherford-Bohr model of the atom. An atom's nucleus. Electrons. Whether this hat makes you think of chemistry, particle physics, or the second half of the 20th century, it has a place in your geeky wardrobe. The sun may be 93 million miles away, but everyone needs protection from it.
This ThinkGeek exclusive men's six-panel hat is black with the ThinkGeek logo embroidered on the back and a yellow atomic model embroidered on the front, a symbol of the Atomic Age. Its snapback is adjustable for a custom fit. One size.

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Retrieved Text: What is an ion with a postive charge called?
What do we call a substance containing atoms of different elements in definite fixed ratios that are bonded together? Can atoms turn into ice? What two forces are at work in the nucleus of an atom? What is the equation for beta decay of americium-243? How many valence electrons does krypton have?

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Retrieved Text: semiconductor is like that of an insulator. The main difference is that the semiconductor has a much smaller energy gap EI/ between the top of the highest filled band (called the valence band) and the bottom of the vacant band just above it (called the conduction band). Thus, there is no doubt that silicon (Ell = 1.1 eV) is a semiconductor and diamond (Ell = 5.5 eV) is an insulator. In silicon-but not in diamond-there is a real possibility that thermal agitation at room temperature will cause electrons to jump the gap from the valence band to the conduction band. In we compared three basic electrical properties of copper, our prototype metallic conductor, and silicon, our prototype semiconductor. Let us look again at that table, one row at a time, to see how a semiconductor differs from metal.
silicon in which the portion has J.ee projecte4 ont8 a ,Jane; compare the figure with which represents the unit cell of the lattice in three lIimensions. Each SiliCORatom c contributes its pair of 3s electrons and its pair of 3p electrons to form a rigid two-electron covalent “nd with each ef its four nearest neighbors. (A covalent bond is a link between two atoms in which the atoms share a pair of electrons.) The four atoms that lie within the unit cell in show these four bonds. The electrons that form the silicon-silicon bonds constitute the 1’llle1¥’eHnjof the silicon s.mplt. U an e\ectrot\ is tom ftOm one of these ~ends so that it some free to wander throughout the

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Retrieved Text: For further discussion, see also Theoretical chemistry and Quantum chemistry.
In chemistry, a chemical bond is an arrangement of electrons among atoms that keeps the atoms together. The bond originates in the electrical attraction of opposite charges, and is made possible by the attraction of the positive nucleii of atoms to the electrons associated with them. The central issue in understanding the bond is finding how the electrons associated with atoms distribute their negative charge so as to overcome the natural repulsion between positive atomic cores. A useful understanding can range from an entirely qualitative model based upon the attraction of one atom for electrons compared to another (their electronegativity) to very detailed computer calculations based upon quantum mechanics.
If the total energy of two or more bound atoms is lower than the sum of the energies of the free component atoms, the aggregate of atoms form a stable molecule (or crystal) and the energy lowering is the binding energy of the molecule (or crystal).
The chemical bond takes on many forms, ranging from simple atomic pairs in a diatomic molecule, to large organic molecules like DNA. Examples of atomic pairs are two nitrogen atoms chemically bound to the stable dinitrogen molecule (written as N2) and a hydrogen atom with a fluorine atom forming hydrogen fluoride (HF). As an example of larger complexes, carbon (C) and oxygen (O) form the pair C—O that appears in many organic molecules, one of the simplest being methanol H3C—OH. Atoms may also be bound to form a crystal, such as sodium (Na) and

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Retrieved Text: The atomic mass number is the number of protons plus the number of neutrons in an atom. Fluorine, chlorine, bromine, and iodine make up Group 7, the halogens.
Remember, we said ions were elements with a positive or negative charge. If you've found an issue with this question, please let us know. By having three electrons in the outside shell, boron should be a metal element. This property can be easily seen with mercury.
Radioactive decay is the result of an unstable nucleus in an atom. Of the three naturally occurring ones, only uranium is likely to be referred to in any way in a basic chemistry course. At the end of the change, the alcohol is gone and has been replaced by carbon dioxide a colorless gas and water vapor water that is in the gas state.
How much of a 100 mg sample of I-123 is left after 60 hours? These properties are things that you can observe or measure about the substance. Preservation of food. We can tell the number of valence outer electrons as well as other useful properties an element has from its group number.
Future Changes to the Periodic Table The periodic table is not set in stone. The inert gases or noble gases all have a complete outside shell of electrons.
He left a space for gallium below aluminum, naming it eka- aluminum, and predicting the properties of gallium fairly closely.
All of these elements are metals and exist as solids at room temperature. The solution to this problem came in 1913 when Henry Moseley

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Input Text: Read the passage below and choose the right answer to the following question (choices are earth or mars ):

The further objects are away from each other, the smaller the gravitational force.


The sun exerts gravitational force on all the planets, which has a higher gravitational force earth or mars?

Target Text: earth

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Retrieved Text: Question: Why does the earth orbit the sun? Why doesn't the gravitational force cause all the planets to just crash into the sun?
Asked by Zobo64 to Colin, John, Kevin, Shikha, Triona on 13 Nov 2014. This question was also asked by xX_FaZe_FiNnErS_Xx.
You’re right that the Sun puts a huge gravitational force on the Earth (and every other planet too). Earth doesn’t fall into the Sun because the Earth has a velocity in the direction at 90 degrees to the force of the Sun’s gravitational pull. If the Sun’s gravitational pull wasn’t there, the Earth would travel on in a straight line. But the gravity of the Sun alters its course, causing it to travel around the Sun in an almost circular orbit.
The planets (plus asteroids, comets, dwarf planets etc) are lucky. They’re in nice stable orbits. The Sun is made of stuff that wasn’t so lucky and fell into it as the Solar System formed 4.5 billion years ago.
The Earth is not rotating around the sun: but the Earth and Sun are rotating around a common point between the two which is really really close to the Sun. The same for all the other planets, but it gets even more complicated in that all the planets exert gravitational forces on each other too. So the Sun is pulling the earth towards it and Jupiter is pulling the earth in the other direction away from the Sun. This orbital system has taken billions of years to stabilise and settle down and is still evolving over time really

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Retrieved Text: Calculate the force of gravity between a newborn baby of mass 4 kg and the obstetrician of mass 75 kg, who is 0.2 m from the baby.
Which exerts more gravitational force on the baby, Mars or the obstetrician, given that Mars has a mass of 6.4 1023 kg and is 8. 1010 m from Earth?
obstetrician exerts more gravitational forcethen Mars.

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Retrieved Text: Gravitational pull depends on two things: (1) the size of an object, and (2) your distance from it. The bigger the object, the greater the pulling power—and the closer you are to an object, the greater the pulling power. But note, contrary to popular belief, spinning objects generate no pulling power—i.e., rotating planets do not create gravity.
Imagine a pair of dice—just a few centimeters from one another—floating in outer space! In a day or so, the two dice will come together. Why?—because each of the dice has mass, which exerts gravitational pull, which draws the pair together as they orbit round their mutual center of mass.
All objects with mass or energy create gravity waves—which attract other objects. Remarkably, gravity waves move at the speed of light! Scientists now believe that gravity waves actually curve, twist, and distort the fabric of space and time! The size of a gravity wave depends on the size of the object that emits it—small objects create tiny ripples, while large objects create gigantic tidal waves. And because gravity waves collide, it turns the universe into a churning sea of gravity.
As the story goes, Sir Isaac Newton “discovered” gravity when he saw an apple fall from an apple tree. With clever mathematics, Newton proved that objects are in constant freefall towards the center of the Earth, and he also proved that all objects, regardless of their weight, fall to the ground at the same rate of speed. Both feather and hammer fall at the same rate and both hit the ground at

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Retrieved Text: Titan, the largest moon of Saturn, has a mean orbital radius of 1.22 x 109m. The orbital period of Titan is 15.95 days. Hyperion, another moon of Saturn, orbits at a mean radius of 1.48 x 109m. Use Kepler’s third law of planetary motion to predict the orbital period of Hyperion in days.
The mass of Earth is 5.97 x 1024 kg, the mass of the Moon is 7.35 x 1022kgand the mean distance of the Moon from the center of Earth is 3.84 x 105 km. Use these data to calculate the magnitude of the gravitational force exerted by Earth on the Moon.
Find the mass of the bowling ball.
Compare the weight of the first ball with the gravitational force exerted by the second ball.
The planet Mercury travels around the Sun with a mean orbital radius of 5.8 x1010m. the mass of the Sun is 1.99 x 1030 kg. Use Newton’s version of Kepler’s third law to determine how long it takes Mercury to orbit the Sun. Give your answer in Earth days.
Io, the closest moon to Jupiter, has a period of 1.77 days and a mean orbital radius of 4.222 x 108 m. Use this information together with Newton’s version of Kepler’s third law to determine the mass of Jupiter.
Earth has an orbital period of 365 days and its mean distance from the Sun is 1.495 x 108 km. The planet Pluto’s mean distance from the Sun is 5.896 x109 km. Using Kepler’s third law, calculate Pluto’s orbital period in Earth days.
The mass of Earth is

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Retrieved Text: The weight (or the mass) of a planet is determined by its gravitational effect on other bodies. Newton's Law of Gravitation states that every bit of matter in the universe attracts every other... How to Calculate Your Weight in Other Planets Calculate your weight by multiplying mass by the gravity on the surface of the planet. Weight = Mass x Surface Gravity Then surface gravity is the gravitational force exert on the surface.
How do scientists measure or calculate the weight of a planet?
Planet Facts There are 8 planets in our solar system, they are Mercury , Venus , Earth , Mars , Jupiter , Saturn , Uranus and Neptune . With the exception of Neptune and Uranus the other 6 planets can be seen unaided and all 8 are visible with a small telescope or binoculars. how to write about things you know nothing about To investigate your hypothesis, find out how much you weigh on other planets using the CERES Solar System Weight Calculator. Then use the Solar System Data Table or books from the school library to see which planets have properties that might affect your weight on other planets.
g p = gravitational acceleration of planet Plug in the values for G, M, m, and r in the equation and solve. Check and see if your answer comes close to the gravitational acceleration in the table of values for that planet.
Weight is the force you feel due to gravity, and 'apparent weight' is the force you feel due to your total acceleration. This means

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Retrieved Text: I enclose a copy of the Society�s lecture programme for the 2005/2006 session. The first lecture takes place on Thursday the 22nd September and will be on The Cassini Huygens Mission by Nick Achilleos of Imperial College.
Ordinary members � Simon Lang, Eric Morgan, John Oakes, Michael Sabel, Betty Weale.
1905 was Einstein�s annus mirabilis. He published five seminal papers on Physics. One, on light as quanta, effectively invented Quantum Optics; two demonstrated the reality of the kinetic-molecular theory of heat; two more resolved the fundamental problems between classical mechanics and electrodynamics through his Special Theory of Relativity and postulated E=mc�. But it took ten more years to develop his General Theory of Relativity; this offered the only development in gravitational theory since Newton�s in 1687. The article by Doug Daniels overpage will bring you up to date.
The conventional theory for the formation of the gas giant Jupiter postulates its growth from a core of solid material by the gravitational attraction of gas, mainly hydrogen and helium, from the protoplanetary nebula until it reached its present size of 318 earth masses. It is argued that the solid material could only collect in relatively cool regions beyond the �ice line�, typically at least 3 AU from the star. (An astronomical Unit, AU, is the sun-earth distance). So far we have been able to detect spectroscopically many extra-solar planets, mainly by the perturbation of the radial velocity of the star; the method favours the detection of massive gas giants with short orbital periods. Ten years ago �Pegasi� planets were discovered

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Retrieved Text: Force is defined as the pull or push which produces or tends to produce, destroys or tends to destroy motion in a body, increases or decreases the speed of the body or changes its direction of motion. Therefore, Force is an external or internal agent present to influence the natural state of motion of an object.
Sir Isaac Newton has established the subsequent formula relating to the mass and acceleration of a body when it is subjected to force.
Force (F) = Mass (m) x Acceleration (a).
The magnitude of force can be made use of in diverse types of units founded on different systems of measurements.
Therefore, the unit of forces are categorized into two system called absolute and gravitational systems. The measurement of forces in absolute system is not dependent on gravitational force while the measurement of forces in gravitational system is dependent on gravitational forces. Hence, the measures of force in gravitational system vary on other planets compared to earth.

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Retrieved Text: The politician Douglas Carswell (UKIP) has recently been arguing with the scientist Paul Nightingale about what causes the tides on Earth. Carswell said it was the gravitational influence of the Sun and Nightingale said it was the Moon. The debate came up in the context of Brexit. Using the tides as an analogy, Nightingale had argued that trade relationships with the EU were more important than those with more distant giants like China.
Giving Carswell the benefit of the doubt (after all, hundreds of years' worth of expert opinion might be wrong) we decided to do a back-of-the-envelope calculation to see who's right.
where is the gravitational constant.
However, the tidal force the Moon exerts on the Earth is calculated by working out the ratio between its gravitational pull on the near side of the Earth and its pull on the far side.
This means that the gravitational pull of the Moon is stronger on the near side of the Earth than it is on the far side.
Now let’s do the same for the Sun, writing for the distance between Earth and Sun, centre to centre.
This means that the gravitational pull of the Sun is only stronger on the near side of the Earth than it is on the far side.
We therefore conclude that Nightingale is right. The ratio is far bigger for the Moon than it is for the Sun, so the tides we see are due to the Moon.
Interesting and fun to read.

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Retrieved Text: News & Stories > Blue Sky Science > How does the moon affect the tides?
Gravity is what makes the ocean tides happen. Gravity is the attractive force that all matter exerts on other matter, and it’s what holds us to the Earth. All the matter that makes up the Earth attracts each other, and the result is that it pulls itself into this round ball, which we know as the globe.
If there were no other external factors, the Earth would be a smooth, round sphere, and the oceans would be the same depth everywhere and would never change. But our moon exerts its own gravitational force that affects some of our life on Earth.
As the Earth rotates, the position relative to the moon changes, so the bulge moves. At any one location the sea level goes up and goes down as the bulge passes that location. Every six hours the tide goes from high to low and high to low again. Over 24 hours you typically see two high tides and two low tides.
The sun can also be influential.
The sun, if it happens to be aligned with the moon, also exerts a gravitational force and can work together with the moon to make the tides even stronger. If the sun is unaligned with the moon, then it works against the moon, reducing the high tide and raising the low tide a little bit so the peak and valley are not as large.
The process is more complicated the oceans have a shape, different depths and coastlines, so

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Retrieved Text: 1. Consider this distance vs. time graph of an object.
During which intervals is the object being acted on by a force?
2. An objectâ€™s velocity vs. time graph is shown below.
During which interval is there no net force acting on the object?
3. When forces acting on an object are balanced, which characteristic of motion is zero?
4. A spaceship in deep space fires its engines for 3 seconds. Which describes its motion at the end of the 3 seconds when the engines are turned off?
It moves with a constant speed.
It moves with increasing speed, then the speed gradually decreases.
5. A 20.0-N physics textbook rests on a table. What is the force the table exerts on the textbook?
6. A sign of uniform density weighing 315 N is supported by a rigid horizontal pipe of negligible mass and a cable that makes a 50.0° angle with the wall.
What is the tension needed for the cable to support the sign?
7. A 20-kg mass is suspended from two ropes, as shown in the diagram below.
Which of the following relations is true?
8. This graph shows weight versus mass for a group of objects on planet X.
What is the acceleration due to gravity on planet X?
9. A 45-kg object is given a net force of 500 N. What is its acceleration?
10. In the drawing below, the identical inclines are frictionless and the mass of cart X is twice that of cart Y.
If the carts are allowed to roll down the inclines, which statement will be true?
The carts will reach the bottom of the inclines

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Retrieved Text: One of the things that makes me feel good about the world around me is gravity. It is a very weak force, and yet every body of matter in space exerts gravitational force on every other body in space. That means you and I. We are pulling, at each other, at the planets, stars, rocks, trees, gaseous clouds. Everything. So I wanted to make something that was, in a vague way, about gravity. Input force is stored in a spring, then transferred to a fly-wheel, then to a gear, then a lever, and finally a mangle-gear driving a rod at an odd angle. On that rod sits a figure, anchored to the machine.
I wish I had process images, but I didn't take any.
Lovely. This is great stuff.

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Retrieved Text: The tidal force is an apparent force that stretches a body towards and away from the center of mass of another body due to a gradient (difference in strength) in gravitational field from the other body; it is responsible for diverse phenomena, including tides, tidal locking, breaking apart of celestial bodies and formation of ring systems within the Roche limit, and in extreme cases, spaghettification of objects. It arises because the gravitational field exerted on one body by another is not constant across its parts: the nearest side is attracted more strongly than the farthest side. It is this difference that causes a body to get stretched. Thus, the tidal force is also known as the differential force, as well as a secondary effect of the gravitational field.
In celestial mechanics, the expression tidal force can refer to a situation in which a body or material (for example, tidal water) is mainly under the gravitational influence of a second body (for example, the Earth), but is also perturbed by the gravitational effects of a third body (for example, the Moon). The perturbing force is sometimes in such cases called a tidal force (for example, the perturbing force on the Moon): it is the difference between the force exerted by the third body on the second and the force exerted by the third body on the first.
Figure 4: The Moon's gravity differential field at the surface of the Earth is known (along with another and weaker differential effect due to the Sun) as the Tide Generating Force. This

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Retrieved Text: What is Gravity? Information on what some people think gravity really is.
Scientists still have a tough time understanding what this force is. This remains one of the greatest challenges of 21st Century science.
Here is the mainstream view of what gravity is. After we reveal some sources of alternate views of what gravity is.
Gravity is a force pulling together all matter (which is anything you can physically touch). The more matter, the more gravity, so things that have a lot of matter such as planets and moons and stars pull more strongly.
Mass is how we measure the amount of matter in something. The more massive something is, the more of a gravitational pull it exerts. As we walk on the surface of the Earth, it pulls on us, and we pull back. But since the Earth is so much more massive than we are, the pull from us is not strong enough to move the Earth, while the pull from the Earth can make us fall flat on our faces.
In addition to depending on the amount of mass, gravity also depends on how far you are from something. This is why we are stuck to the surface of the Earth instead of being pulled off into the Sun, which has many more times the gravity of the Earth.
Here is our favourite alternate view of what gravity is.
Reproduction in whole or in part in any form or medium without express written permission of antigravitytechnology.net is prohibited.
Copyright © 2001 antigravitytechnology.net All rights reserved.

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Retrieved Text: In case you have never heard of this thing, the James Webb Space Telescope (JWST) is essentially the planned next generation Hubble Space Telescope. Yes, with current budget discussions, there is a chance this telescope will not be launched. I think that is sad. As Phil Plait (of Bad Astronomy) puts it: the US spends more on lottery tickets than on NASA.
But rather than talk about the budget, let's talk about the JWST's planned orbit. The Hubble Space Telescope orbits the Earth. The JWST will orbit the Sun. However, it will orbit in a special way so that it will always be in position with the Earth between it and the Sun (but not in the Earth's shadow). This location is called the L2 Lagrange point.
If you really want to understand the L2 orbit, you need to first look at the Earth's orbit. Here is a diagram of the Earth orbiting the Sun (not anywhere close to scale).
MS is the mass of the Sun.
mE is the mass of the Earth.
rE is the distance from the center of the Earth to the center of the Sun.
The force and the acceleration are both towards the Sun (the center of the Earth's circular motion). So, I write this as a scalar equation by putting in the values for the acceleration and the force.
The key here is that for the Earth to be in a circular orbit with a certain angular velocity (in this case about 2π radians per year), the Earth must orbit at a particular radius. What if

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Retrieved Text: NASA - How Far? How Faint?
How much brighter is the Sun as viewed from the planet Mercury as compared to Earth? How much fainter is it at Neptune? How strong is the Sun's gravitational pull on the Voyager 1 spacecraft now as compared to when it was at Jupiter? How much pull does the Sun exert on the nearest star?
Actually, all of these questions can be answered through a very simple mathematical relationship known as the inverse square law.
It is a simple division problem that can be applied to a variety of interesting situations that affect planets, spacecraft that venture out into deep space and a number of other natural phenomena.
The equation relates the relative distances of two objects as compared to a third. Typically one of the objects is Earth, the second is a spacecraft and the third is the Sun. To begin, lets make some generalizations. There is a certain amount of sunlight reaching Earth at any given moment. This is not an absolute quantity since Earth is closer to the Sun at some times of the year verses others and the number of sunspots effects the Sun's energy output, but overall the Sun is remarkably constant in its behavior. If it were not, life on Earth might be impossible.
We can describe the amount of the Sun's energy reaching Earth as 1 solar constant. The average distance from the Sun to Earth is 149,597,870.66 kilometers (92,955,807.25 miles) which we can simplify to what astronomers call 1 Astronomical Unit or 1 AU. So Earth is

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Retrieved Text: How are the rings of planets formed and what are they made out of?
The rings around planets like Jupiter and Saturn (yes Jupiter has rings!) are made up of bits of ice and rock.
They form when asteroids,comets, or any other large objects pass too close to the planet and are torn apart by the planet's gravity. There is a point around the planets called the Roche Limit. This is the point where gravity will tear apart an incoming object, and prevent the particles from re-accreting back into a larger object.
Essentially, rings are just thousands of tiny moonlets that orbit a planet and don't clump back into larger objects.
There is a problem, however, if the debris orbiting a planet orbits too closely. Because gravitational force varies with distance, the different accelerations between two points at different distances from a massive object create a tidal force that has a stretching effect on nearby objects. This force from the Sun and Moon creates tides on opposite sides of the Earth, for example. When the tidal force is large enough, it overcomes the gravitational forces trying to bring individual particles together. Within a given distance from a planet, called its 'Roche Limit', tidal forces prevent debris from aggregating into larger bodies.
Planetary rings, then, consist of millions of separate small rock and ice particles, each maintaining their own orbit around the host planet. From a distance, these small orbiting particles only APPEAR to be a continuous, solid ring.

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Retrieved Text: Gravitation – Gravitation, universal law of gravitation, force of gravitation of the earth (earth’s gravity), acceleration due to gravity, mass and weight, free fall.
Flotation – Thrust and Pressure, Archimedes’ Principle, Buoyancy, Elementary idea of relative density.
The Pull of the Earth – Gravitation, universal law of gravitation, force of gravitation of the earth (earth’s gravity), acceleration due to gravity, mass and weight, free fall.
Why Bodies Float – Floating Bodies: Thrust and Pressure, Archimedes’ Principle, Buoyancy, Idea of relative density.
Centripetal force – The inward force on a body moving in a curved path around another body is called centripetal force.
When we whirl around a stone attached to a string, the force keeping the stone towards the centre of the circle is centripetal force.
Gravitational force – It is the force of attraction between any two masses in the universe.
Force of gravitation due to earth is called gravity. The more remote the body, the less the gravity.
The force of gravitation is a force of attraction only.
G is known as universal gravitational constant and its SI unit is Nm2/ kg2.
The value of G is 6.67 x 10-11 Nm2 / kg2 and in CGS system, it is 6.67 x 10-8 dyne-cm2/ gm2.
(a) the gravitational force of attraction binds us to the Earth.
(b) the moon revolves around the Earth.
(c) the planets revolve around the Earth.
(d) high tides and low tides of the oceans.
All objects falling towards the Earth under the action of gravitational force of the Earth alone are said to be in “free fall”.
Acceleration due to Gravity – The acceleration experienced by

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Retrieved Text: Like the sun attracts the planets, the Aleeka collection uses celestial inspiration to create it's own gravitational force. Concentric rings orbit around a slim and sleek cylindrical center column. Oval globes seem to float almost weightlessly on top.

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Retrieved Text: – Gravity is a force, but it’s not a force of attraction, it’s a force of pressure.
– There is a gravitational flux in motion (it could be named “aether” in motion, “galactic dust” in motion, moving “Higgs field”… science has a big problem calling to same reality with very different names) that pressures on the matter that it finds in its way, trying to pass through it. Depending on the resistance of that matter to be passed through, because of their spatial density, the gravitational flux will create a gravitational field with a specific curvature.
– Gravitational curvatures vary periodically. Gravitational fields expand and contract periodically. When the gravitational field’s pressure on matter is higher because of the higher material resistance, the gravitational curvature will experience a higher refraction or amplitude. The concave gravitational field acts like a longitudinal wave.
– The higher or lower friction of the gravitational flux on matter will determine the periodical gravitational variation and its frequency. When the pressure of the gravitational field is higher the friction on matter will became higher and it will determine a variation on the material spatial distribution, changing its density that will became lowest. It will produce that the gravitational flux passes through matter more easily, experiencing a variation on its curvature. Now the gravitational curvature will have lower refraction because of its lower pressure on matter. It is a periodical process.
– When two gravitational fields that vary periodically entangle, they create in their mutual intersection four new fields that are electromagnetic.
– By “entanglement” I mean the

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Retrieved Text: Like the sun attracts the planets,the Aleeka collection uses celestial inspiration to create its own gravitational force. Concentric rings orbit around a slim and sleek cylindrical centre column. Oval globes seem to float almost weightlessly on top, and the Classic Pewter finish delivers the final soft contemporary touch. All pendants come supplied with 2 x 150 mm and 2 x 300 mm rods.

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Retrieved Text: Our universe is afloat in space.
Everything in the galaxy has mass, which gives it its gravitational force.
So, how is it possible to have our planets levitating around the sun?
What is causing the sun to remain where it is?
The universe is a curious place, what would our world be like if our solar system was a few feet lower or higher than it is?
There must be an end to our universe, or else there would be an infinite amount of space, which is technically impossible, unless we’re in an infinite loop?
Otherwise, there would be no gravitational forces, no pressure, nothing keeping the universe or even our galaxy itself in its current shape.
Years ago, we believed we were the center of the galaxy and everything orbited around us.
Years ago, we believed that our galaxy was the only galaxy in existence.
Then we learned that there are a giant multitude of galaxies, with their own suns, stars and planets… so, that begs the question; What will we know in a few years that will be disproven, then even many more years from now?
Imagine that everything we know about this solar system is a lie.
That we aren’t actually floating in space, but actually perpetually falling downward, toward an infinite abyss of darkness and emptiness, along with all the universes around us.
That one day, we may hit the bottom. That our giant rock will crash. That one day, out-of-nowhere we are wiped out of existence, because our planet has reached the end of its journey.
Imagine that one time that you dreamt that

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Retrieved Text: The term king tide has no scientific definition – in popular usage it refers to any high tide well above average height. The popular concept is that the king tides are the higher high waters which occur around Christmas time. Equally high tides occur in the winter months but these are at night and not as obvious as those at Christmas which generally occur during the day.
2.17m on the Sunshine Coast.
In any 1 year there will be 2 spring tides that are the highest, 1 during summer and 1 during winter. These are referred to as king tides. The king tides occur because of the combined influence of a number of astronomical factors related to the Sun and the Moon (and their alignments) and the gravitational attraction they each have on the water surface of the Earth.
The earth moves around the sun in an elliptical orbit that takes a little over 365 days to complete. The sun has an influence on the tides. Its gravitational force is greatest when the earth is closest to the sun (perihelion – early January) and least when the sun is furthest from earth (aphelion – early July).
The moon has a larger effect on the tides than the sun. The moon moves around the earth in an elliptical orbit that takes about 29 days to complete. The gravitational force is greatest when the moon is closest to the earth (perigee) and least when it is furthest from the earth (apogee – about 2 weeks after perigee).

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Retrieved Text: How can you find force when given time velocity and mass?
Weight (W) is measured in newtons (N) it is a force. It depends on the mass of the objects and the gravitational field strength on the planet. An objects weight can be different on different planets because gravity can be different strength on different planets.... You can further define Δv and Δt: Δv = v f – v i and Δt = t f – t i where v f is the final velocity, v i is the initial velocity, t f is the ending time, and t i is the starting time. Use the formula to find acceleration.
Weight (W) is measured in newtons (N) it is a force. It depends on the mass of the objects and the gravitational field strength on the planet. An objects weight can be different on different planets because gravity can be different strength on different planets.... 4/12/2011 · I gave a thumbs up for the second answer, which basically says: If you start an object of mass m with velocity v, and friction brings the object to rest after a distance s, then you know that the initial kinetic energy (1/2 m v^2) was all spent on doing work against the friction.
How To Calculate Power Based On Force And Velocity?
3/09/2013 · Formula for acceleration/mass when force, distance, and initial velocity are given? Getting distance with mass, force, angle, and final velocity given.? How do you find the average force if the mass, velocity, and distance is given?
angular velocity =

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Retrieved Text: There are four fundamental forces of nature. The four forces are gravitational force, Electromagnetic Force, Weak Nuclear Force, and Strong Nuclear Force. These four forces have strengths with Strong Nuclear Force being the strongest, but has the shortest range. Then it would be Electromagnetic Force which is strong and has infinite range. Next is the weak Nuclear Force which is weak, but has short range. Lastly is the Gravitational force which is the weakest, but it has infinite range.
The definition of Gravitational Force is “the force of attraction between all masses in the universe; especially the attraction of the earth’s mass for bodies near its surface.” This force is the weakest, but it has infinite range. Gravitational force is the type of force that would attract any two objects and it would use mass in order to attract them. We call the gravitational force “attractive.” The reason that we call it attractive is because of all the mass that it attracts. One thing that gravitational force never does is push masses apart it always brings them together.
Next is Electromagnetic Force which is strong and has infinite range. Since this force is infinite range it affects everything in the universe. This force has the special ability not only to attract charges, but it can also repel them. Since the electromagnetic Force has infinite range you would think that it would be weak, but it is actually very strong. Now I’m going to give you an example that blew my mind and tell you how strong the electromagnetic

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Retrieved Text: It was in December 2011 that astronomers working at NASA’s Kepler mission in th US confirmed the existence of the first earth-like planet in the ‘habitable zone’ of a distant sun-like star. The newly confirmed planet, Kepler-22b, is about 2.4 times the radius of earth.
Scientists don’t yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding earth-like planets.
In astronomy and astrobiology, the habitable zone is the region around a star where a planet of earth-like size, composition and atmospheric pressure can maintain liquid water on its surface. In other words, it refers to the belt of orbits around sun-like star where liquid water could exist on a planet’s surface. In the words of Dr Douglas Hudgins, Kepler programme scientist at NASA Headquarters in Washington, USA,“This is a major milestone on the road to finding Earth’s twin."
Kepler-22b is located 600 light-years away from earth. In other words, what we are seeing today has happened 600 years earlier. While the planet is larger than the earth, its orbit of 290 days around a sun-like star resembles that of our world. The planet’s host star belongs to the same class as our sun, although it is slightly smaller and cooler. It is a bit smaller than our sun, so its habitable zone is slightly closer in.
Kepler 22b, as it is known, is 2.4 times the size of the earth and takes 290 days to orbit its star. If it had a reasonable atmosphere, the surface temperature on Kepler

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Retrieved Text: Download "Understanding the motion of the Universe. Motion, Force, and Gravity"
2 Laws of Motion Stationary objects do not begin moving on their own. In the same way, moving objects don t change their movement spontaneously. A force is required to cause a change in motion. We call this the law of inertia. The word inertia was invented from the Latin term for laziness. Objects are lazy, they only change their motion if forced to.
4 Isaac Newton ( ) Newton is one of the greatest thinkers in human history. He made great leaps forward in our understanding of light and optics, the physics of motion, and the nature of gravity. He also co-invented the new field of mathematics known as calculus. Newton s greatest work included much of the foundation of our understanding of physics. In this book, he published his 3 laws of motion.
5 First Law: A body continues at rest or in uniform motion in a straight line unless acted upon by some force. (law of inertia) Object (a) and (b) will remain that way. Object (c) experiences a force.
7 Second Law: A body s change in motion is in proportion to the force and in inverse proportion to the body s mass. (force law) Larger force produces larger acceleration. Larger mass results in smaller acceleration, because the body s inertia ( laziness ) is larger.
9 Third Law: In every action, there is an equal and opposite reaction. (action-reaction pairs) Forces always come in pairs. When one object exerts a force on another, the second

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Retrieved Text: The terms gravity and gravitation are mostly interchangeable in everyday use, but a distinction is made in scientific circles. "Gravitation" is a general term describing the phenomenon by which bodies with mass are attracted to one another, while "gravity" refers specifically to the net force exerted by the Earth on objects in its vicinity as well as by other factors, such as the Earth's rotation.
In everyday life, gravitation is most commonly thought of as the agency which lends weight to objects with mass. Gravitation compels dispersed matter to come together, thus accounting for the existence of the Earth, the Sun, and most of the macroscopic objects in the universe. It is the force for keeping the Earth and the other planets in their orbits around the Sun and for keeping the Moon in its orbit around the Earth. Modern physics describes gravitation using the general theory of relativity, in which gravitation is a consequence of the curvature of space time which governs the motion of objects.
Every object with mass is surrounded by its own gravitational field, which exerts an attractive force on all objects. Assuming a spherically symmetrical planet, the strength of this field at any given point is proportional to the planetary body's mass and inversely proportional to the square of the distance from the center of the body.
The strength of the gravitational field is numerically equal to the acceleration of objects under its influence, and its value at the Earth's surface, denoted g, is approximately expressed below as the standard average.
This means that, ignoring

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Retrieved Text: gravitational field intensity on the surface of the Earth will be calculated as g = 9,8 N/kg.
Gravitational potential energy is always negative. As r approaches to infinity, EG approaches to zero.
Approximate formula can be used in case the difference between r1 and r2 is not much, or ∆h is not very large.
v: Orbital speed (m/s): Orbital speed is the speed is required for an object to stay in orbit above a central body. Orbital speed of the object is undergoing uniform circular motion (m/s). Orbital speed is a constant speed and perpendicular to the gravitational force.
To escape an object from the orbit of the central body, the objects' total energy must be greater than zero. Since the gravitational potential energy of the object is always negative, and depends on the position of the object, the kinetic energy must be increased to make total energy greater than zero. This additional kinetic energy is called the binding energy. when the object escape from the central body, it will no longer to be bound to the central body.
Since the orbital gravitational potential energy does not change at the given location, kinetic energy must be increased to make the orbital total energy greater than zero.
Since the object at rest, kinetic energy of the object equals to zero and total energy of the object equals to gravitational potential energy of the object.
Escape velocity is the minimum velocity needed for an object to escape the gravitational pull of another object at a given distance. To escape an object from the potential well

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Retrieved Text: Each and every one of us is familiar with the force of gravity. It keeps us firmly planted on Earth, it is the force against which we must fight every morning to get out of bed, and it is the reason why climbing a staircase or a mountain requires effort. Thanks to gravity, we glide down snow-covered slopes on our skis, water flows from the mountains to the sea, and apples fall from trees. According to legend, this phenomenon played a significant part when Isaac Newton developed the first mathematical description of universal gravitational attraction, realizing that the same force that makes those apples fall also choreographs the celestial ballet of planets, stars and galaxies.
Without gravity, the moon would not orbit the Earth, the Earth would not revolve around the Sun, and galaxies would not exist. Newton’s profound contribution was to realize that gravity acts on all matter, at every moment, everywhere, in every corner of the Universe. It is universal!
Gravitation is also mysterious and counter-intuitive. The modern theory describing it is general relativity, developed by Albert Einstein in the years following 1910, and published in 1915. According to general relativity, space and time form a structure in which geometry is curved, far from our everyday experience of the world. In the most extreme cases, gravity gives rise to objects as exotic as black holes, from which no signal can escape. It is also at the origin of gravitational waves, discovered very recently thanks to detectors of incredible precision. Another strange aspect of gravity is that

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Retrieved Text: is bitesize good for controlled assessments?
they will be directly proportional.
If you drop a ball onto a hard floor. It will rebound, but even the bounciest ball will not bounce back to its starting position.
The ball behaves like a spherical spring. When the ball hits the floor it exerts a force on the floor and the floor exerts a force on the ball. This force compresses the ball. The force that the ground exerts on the ball does work on the ball, since it is in the same direction as the displacement. The gravitational potential energy the ball has before it is dropped is converted into kinetic energy while the ball is falling and then into elastic potential energy as the force from the ground does work on the ball. But because the material the ball is made of is not perfectly elastic, friction converts some of the energy into thermal energy.
The elastic potential energy stored in the ball when it has lost all its kinetic energy is converted back into kinetic and gravitational potential energy. However the thermal energy is not converted back.
The ball on the floor acts like a compressed spring. It pushes on the floor with a force proportional to its displacement from its equilibrium shape. The floor pushes back with a force of equal size in the upward direction. This force is greater in size than the weight of the ball. The resultant force is in the upward direction and the ball accelerates upward. When the ball's shape is the shape it has

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Input Text: Read the passage below and choose the right answer to the following question (choices are greater or lesser ):

Objects with greater mass have a stronger force of gravity between them.


Jupiter and Saturn are much larger in mass than Earth and Venus, therefore the force of gravity between Earth and Venus is greater or lesser than the force of gravity between Earth and Venus?

Target Text: lesser

#### Retrieved Documents ####

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Retrieved Text: Download "Starting from closest to the Sun, name the orbiting planets in order."
2 Chapter 9 Section 2: The Inner Planets The inner planets are referred to as the Terrestrial Planets. The inner planets are denser and rockier than the outer planets. Mercury is closest to the sun, is smaller than the Earth with less surface gravity, has a slower rotation (one rotation takes 59 Earth days), but has a faster revolution around the sun is equal to 88 Earth days. The length of time that it takes an object to rotate once is the objects period of rotation. The time that it takes an object to revolve around the sun once is the objects period of revolution. Venus is Earth s twin planet because Venus is only slightly smaller than Earth (less dense, less mass) and therefore less gravity. Venus has its differences though. Venus rotates the opposite direction that Earth rotates. We call Earth s rotation prograde (counterclockwise as viewed from above the north pole) and Venus s rotation retrograde (clockwise as viewed from the north pole). On Venus the sun rises in the direction that the Earth s sun sets. Venus has the densest atmosphere of the inner planets and it is mostly CO 2 gas. This CO 2 is a greenhouse gas and Venus is therefore has the hottest surface temperature of any planet in the universe. Radar waves have been used to map the surface of Venus and it closely resembles the valleys, plains and mountains of the Earth. Earth is considered

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Retrieved Text: The weight (or the mass) of a planet is determined by its gravitational effect on other bodies. Newton's Law of Gravitation states that every bit of matter in the universe attracts every other... How to Calculate Your Weight in Other Planets Calculate your weight by multiplying mass by the gravity on the surface of the planet. Weight = Mass x Surface Gravity Then surface gravity is the gravitational force exert on the surface.
How do scientists measure or calculate the weight of a planet?
Planet Facts There are 8 planets in our solar system, they are Mercury , Venus , Earth , Mars , Jupiter , Saturn , Uranus and Neptune . With the exception of Neptune and Uranus the other 6 planets can be seen unaided and all 8 are visible with a small telescope or binoculars. how to write about things you know nothing about To investigate your hypothesis, find out how much you weigh on other planets using the CERES Solar System Weight Calculator. Then use the Solar System Data Table or books from the school library to see which planets have properties that might affect your weight on other planets.
g p = gravitational acceleration of planet Plug in the values for G, M, m, and r in the equation and solve. Check and see if your answer comes close to the gravitational acceleration in the table of values for that planet.
Weight is the force you feel due to gravity, and 'apparent weight' is the force you feel due to your total acceleration. This means

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Retrieved Text: With eight other planets, dozens of moons, thousands of minor planets, myriads of comets and meteoroids and in addition interplanetary dust which circle around a central star named the Sun, Venus is a member of a collection of celestial objects which is called the Solar System. It extends over 12,000 million kilometres in space. Counting from the Sun, Venus is the second planet. Venus' orbit is the most circular of any planet, with an eccentricity of less than 1%. The dominant body is the Sun which accounts for more than 99% of the mass of the Solar System. Our Solar System was once regarded as the largest and central part of the Universe. But today we know it is just a tiny speck compared with the rest of the Universe.
Venus belongs to the group of planets from Mercury to Saturn that are bright and easily seen by the naked eye, and well known to the ancients. The three most distant planets - Uranus, Neptune, and Pluto - were discovered after the invention of the telescope in 1609. Uranus and Neptune can be seen with a pair of binoculars, but to detect Pluto requires a moderately-sized telescope.
Compared to the Sun, Venus and the other planets are relatively cold and only visible by reflected sunlight. To observers on Earth, both Venus and Mercury show phases like the Moon, because their orbits lie inside the Earth's orbit. So Venus and Mercury are called inferior planets. On the other hand, Mars, Jupiter, Saturn, Uranus and Neptune lie outside, so they

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Retrieved Text: Interplanetary space missions can be launched only at certain times. These launch windows are dependent upon both the relative positions of Earth and the target planets, and the capabilities of the available launch vehicles. The primary launch period for Cassini, based on the alignment of the planets and the capabilities of the Titan IV/Centaur launch vehicle, was in October 1997. The launch boosted the spacecraft into a Venus-Venus-Earth-Jupiter Gravity-Assist (VVEJGA) trajectory toward its final destination of Saturn.
A gravity assist flight path is required because the spacecraft is too heavy to be injected into a direct trajectory to Saturn. Under such a plan it would not acquire enough speed to reach Saturn in a realisitic time scale or have sufficient propellant left over to allow braking for orbit insertion around Saturn.
The principle of gravity assist boosts the spacecraft's velocity because the planet and the spacecraft tug on one another while orbiting the Sun. The spacecraft makes the planet lose some of its orbital momentum. From a planet's point of view, the spacecraft departs with no net energy gain, but from the Sun's point of view, the energy exchange makes a very small change in the planet's solar orbit. That amount of energy, though, benefits the tiny spacecraft substantially. The power comes from the planet's motion about the Sun.
The Moon as seen by Cassini from a distance of about 377 000 km, around the time of the Earth gravity assist on 18 August 1999.
Io transits the face of Jupiter, as seen by Cassini on 1 January 2001, two

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Retrieved Text: Are you a morning person? If so, and you’re blessed with clear skies, the next several mornings are for you. Just look east, the direction of sunrise. You’ll find the moon sliding by three bright morning planets.
From top to bottom, this planetary lineup showcases Jupiter, Saturn and Venus. Wake up no later than one hour before sunrise to see the spectacle. Think photo opportunity!
On the morning of February 27, 2019, the waning crescent moon closely couples up with the brilliant planet Jupiter as viewed from North America. Elsewhere around the world, the moon is not as close. From the world’s Eastern Hemisphere – Europe, Africa, Asia, Australia and New Zealand – the moon shines to the west of Jupiter on February 27. For all of us, Jupiter and our companion moon will appear very bright and close enough to make waking up early more than worthwhile.
View at EarthSky Community Photos. | Steve Pond in East Grinstead, Sussex, England, caught the waning moon and planets the last time the moon moved through this part of the sky, in late January and early February 2019.
The lighted side of a waning crescent moon points east, the direction of sunrise. The planets Saturn and Venus lie to the east of Jupiter, so the lit face of the moon will point toward the other two planets on the morning of February 27. Notice that the planets and moon make a line on our sky’s dome. This line shows you the whereabouts of the ecliptic, or Earth-sun plane. Since the other planets

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Retrieved Text: Early this month in the twilight just after sunset look for Venus still bright in the west. Then look a little more and not far away you will find another object shining without twinkling. That will be the planet Saturn. Both will have disappeared into the sunset glow by the end of the month.
Planets appear to move amongst the fixed stars and so attracted the attention of the early civilisations. Saturn was named by the Romans for the father of the king of the gods, Jupiter. This planet was the most distant known to the ancients and travelled through the stars more slowly than any other planet they watched. Thus it seemed logical to name it for an elderly and presumably slow-moving god. The planet speeding fastest was called Mercury – the messenger of the gods whose sandals were winged. Venus is the brightest and most beautiful planet visible from Earth and not surprisingly was named for the goddess of beauty and love.
As you will see, Venus is far more brilliant than Saturn. Indeed you may not be able to make out the latter until the twilight begins to darken. Does this mean that Venus is bigger than Saturn? By no means – it is just an optical effect of distance. Just as a candle in your hand would seem brighter than a searchlight miles away so nearby but tiny Venus outshines gigantic but distant Saturn. Both shine by reflected sunlight.
In between Earth and Saturn lie the orbits of Mars, the asteroids and Jupiter. It is

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Retrieved Text: Cosmic bodies may have different shape of orbit: 8-shape, elongated and circular. This article considered only the movement on orbits almost the circular. The planets and some their satellites rotating, usually, on such orbits.
In an ideal case, when these two forces are equal, the vector of speed of a rotating body is directed on a tangent to an orbit, perpendicularly radius. However, in the actual world, it is difficult to find something ideal. The predominance of one force, over another leads to a deviation of a vector of speed aside greater force and to rotation on a spiral.
If force of gravitation prevails, the vector of speed deviates to the center of rotation, and movement goes on a descending spiral. If centrifugal force prevails, movement goes on an ascending spiral. The last satellite can 'come off ' from the star, if force of gravitation significantly will weaken. So in cosmos appears free moons. The satellite, nearest to the center, rotates on a descending spiral, because of predominance of force of gravitation. Ultimately, it can lead to falling of the satellite on the central body. Both these forces are not constant and tend to equilibrium.
If the orbit has removing, the speed will be decreasing and, consequently, centrifugal force will be decreasing too. That is, the centrifugal force as though would, adjusts to the changing force of gravity. Although these two forces are not equal, they can be regarded as relatively equal at this point of time Fc=-Fg.
Fc=-mp*v2/R, mp – mass of planet, v – speed of planet, R

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Retrieved Text: The reason they are considered to be sister, or twin planets, is because they are almost identical in size, and because they both appear to be blue. Their chemical makeup is almost identical as well.
Where is the planet Uranus?
Uranus is the 7th planet from our Sun.\n. \nIt's orbit lies between the orbits of Saturn and Neptune..
Why was the planet uranus named uranus?
What planet is after Uranus?
How far away is Uranus from Neptune?
i want the anwser Comment: Unfortunately there isn't an exact answer. These planets orbit the Sun at different speeds and the distance between them is always changing.
Which is bigger Uranus or Neptune?
Uranus is a little bit bigger if you measure it with Neptune, buteven though Uranus is bigger- Neptune is actually heavier if youmeasure their weight. Which means even if Uranus is bigger, Neptune is heavier.
When were telescopes used to see and to photograph the planets Neptune Uranus and Pluto?
Uranus was discovered by Sir William Herschel in 1781. Neptune was discovered by John Couch Adams in 1846. Pluto was discovered by astronomer Clyde Tombaugh in 1930.
What is the distance between the planet Uranus and Neptune in miles?
Who discovered the planets Jupiter and Saturn and Uranus and Neptune and when?
Why is Uranus a planet?
What is the distance between the planets Uranus and Neptune?
The first planets discovered since ancient times were Uranus and Neptune How were they discovered?
Is the planet Neptune colder than Uranus?
Because Uranus's internal heat is lower than Neptune's -- possibly because it doesn't have a moon as large as Triton providing friction from gravitational

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Retrieved Text: "The discovery of a dark ribbon of weak hydrogen ion emissions that encircles Jupiter has overturned previous thinking about the giant planet's magnetic equator."
The smaller vortices also seem to come in - + pairs, like sun spots, and occasionally resolved in to more concentric 'tubes' .
"The latest data sent back by the Juno and Cassini spacecraft from giant gas planets Jupiter and Saturn have challenged a lot of current theories about how planets in our solar system form and behave.
"The detailed magnetic and gravity data have been "invaluable but also confounding," said David Stevenson from Caltech, who will present an update of both missions this week at the 2019 American Physical Society March Meeting in Boston. He will also participate in a press conference describing the work. Information for logging on to watch and ask questions remotely is included at the end of this news release.
""Although there are puzzles yet to be explained, this is already clarifying some of our ideas about how planets form, how they make magnetic fields and how the winds blow," Stevenson said.
"Cassini orbited Saturn for 13 years before its dramatic final dive into the planet's interior in 2017, while Juno has been orbiting Jupiter for two and a half years.
"Juno's success as a mission to Jupiter is a tribute to innovative design. Its instruments are powered by solar energy alone and protected so as to withstand the fierce radiation environment.
"Stevenson says the inclusion of a microwave sensor on Juno was a good decision.
""Using microwaves to figure out the deep atmosphere was

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Retrieved Text: I recently realized that when I say “ice,” most people don’t understand what I mean.
I am a planetary scientist, and I have studied (among other things) the ice giants of our solar system: Uranus and Neptune. What do you think “ice giant” means? It does not mean that Uranus and Neptune have crystalline water-ice interiors. Much like other potentially misleading words “rock,” “sand,” and “haze,” the word “ice” has a different and particular meaning to planetary scientists.
Only Voyager 2 has visited the ice giants, Uranus (left) in 1986 and Neptune (right) in 1989. These Voyager portraits are newly reprocessed to show the 2 planets at correct relative size and color. Since Voyager, planetary astronomers have studied the ice giants from Earth and have seen their faces change.
Uranus and Neptune, like all the other planets, formed within the solar nebula, a disk of material surrounding our newborn star. Some nebula materials -- silicate minerals or iron, for instance -- were in the solid phase almost everywhere in the nebula, except very close to the young Sun. Other materials, such as hydrogen and helium, were gaseous at any distance from the Sun. But some materials, like methane, ammonia, and water, were gases at the higher temperatures close to the Sun, and snowy solids farther away.
Close to the Sun, only silicates and metals could condense. Farther from the Sun, more volatile components -- chiefly water -- could condense, coating dusty particles with ices.
The behavior of ices in the early solar system explains the difference between the giant planets Jupiter,

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Retrieved Text: While we have been learning about the nine planets in our solar system since childhood, of late there has been a bit of confusion about the number of planets with Pluto being knocked off the list.
Solar system is a minute component of the vast universe which was formed billions of years ago. It consists of the Sun and several celestial bodies revolving around it. These include planets (and their satellites), asteroids, meteoroids, etc. Until 2006 the number of planets in our solar system was nine, but the exclusion of Pluto has left us with only eight planets.
The Sun is the center of our solar system and has eight planets orbiting it. These include―starting from the nearest to the Sun―Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Initially considered a planet, Pluto was officially declared a dwarf planet by the International Astronomical Union (IAU) in 2006, thus bringing the number of planets down to eight. Let's have a brief look at each of these planets.
Mercury: Mercury is the smallest planet in our solar system. At 3031.670 miles, its diameter is 38 percent the diameter of the Earth. It has extreme climate with temperature ranging between −180 to 430 °C. It is located at a distance of 0.39 AU. On the basis of information sent by Mariner 10 spacecraft, scientists suspect that some volcanic activity is occurring on Mercury.
Venus: Venus is a small, rocky planet, typically characterized by a thick blanket of yellowish clouds of sulfuric acid. With a diameter of 7521.076 miles, Venus is bigger than

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Retrieved Text: The year was 2565: Humans had colonized most of their solar system. There were orbiting habitats around Venus, Earth, Mars, Jupiter, Neptune, and in the rings of a Saturn and Uranus. Diamonds were mined in the heavy gravity of Uranus and shipped back to Earth while fossil fuels where found on Jupiter and Saturn. Colonies had formed on most of the moons of the gas giants and economy was booming for rich businessmen. In the later years before colonization, the peoples of earth decided that they would share the wealth. However, it was usually the poor who were sent to be colonists on some worlds. One such place was the floating cities of Neptune.

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Retrieved Text: Here's another thought: Try our best not to use the DailyMail (UK) as a source or citation for anything you ever do again in your life, or at least not here in the TB Forum. The reason is, it has a terrible global reputation for fear-mongering, exaggeration and playing to the crowds' lowest imaginable taste. Using this source, no matter how impressive in it's immediate appearance, will do more to damage your case and your reputation - right out of the starting gate! - than any statement or remark you might subsequently make in connection with that source or citation.
Re: Does gravity make the core compact?
Although this is not entirely related to the opening post, the gravity mapping just underlines that the gravity constant (G) is misguided and would have implications on any gravity driven model. The question whether it may be related to charge is a good one, and Wallace Thornhill has brought up the very same issue. I really recommend the DVD set of his seminar at SIS this summer, where he summarized the issues of current cosmology and gravity, as well as explaining Plasma Cosmology and The Electric Universe.
Select "Other Purchases" and type "W.Thornhill Electric Universe DVDs"
But I feel that clever visual representation should help intellectually honest ones to intuitively realize this: if our planet formed as a result of a gravity-driven coalescing of a spinning cloud of matter, it wouldn't have resulted in a truly round planet. Thus gravity is NOT be the primary driving force behind planet formation.
That's my non-scientist take

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Retrieved Text: A conjunction of Mercury and Venus appears above the Moon, as viewed from the Paranal Observatory in northern Chile.
When two objects always appear close to the ecliptic—such as two planets, the Moon and a planet, or the Sun and a planet—this fact implies an apparent close approach between the objects as seen on the sky. A related word, appulse, is the minimum apparent separation on the sky of two astronomical objects.
Conjunctions involve either two objects in the Solar System or one object in the Solar System and a more distant object, such as a star. A conjunction is an apparent phenomenon caused by the observer's perspective: the two objects involved are not actually close to one another in space. Conjunctions between two bright objects close to the ecliptic, such as two bright planets, can be seen with the naked eye.
A conjunction of Mars and Jupiter in the morning of 1 May 2011, when, about an hour before sunrise, five of our Solar System's eight planets and the Moon could be seen from Cerro Paranal, Chile.
More generally, in the particular case of two planets, it means that they merely have the same right ascension (and hence the same hour angle). This is called conjunction in right ascension. However, there is also the term conjunction in ecliptic longitude. At such conjunction both objects have the same ecliptic longitude. Conjunction in right ascension and conjunction in ecliptic longitude do not normally take place at the same time, but in most cases nearly at the same time. However, at triple

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Retrieved Text: At about 1000 times larger in volume compared to Earth, Jupiter is the largest planet in our solar system.
In fact, if Jupiter was 50 times larger than it is now, it would be a star on its own. And if you combined all the planets in the solar system, it still wouldn’t be as big as Jupiter.
Other than its tremendous size, Jupiter has tons more superlatives. What are some other facts about Jupiter?
Jupiter spins at an incredible pace. The velocity at Jupiter’s equator is about 28,000 miles per hour, compared to Earth’s 1000 mph.
This means that one day on Jupiter takes a bit less than 10 hours. Because of its fast rotation and heaping size, the coriolis effect is extraordinary in size.
Jupiter’s weather is so extreme that we can see it from space. For example, astronomers have observed an everlasting hurricane ever since we’ve first seen it.
We see this enormous cyclone as a red spot on it because of the Coriolis effect. Also, the Coriolis effect gives Jupiter its banded appearance.
The aurora borealis isn’t unique to Earth. Jupiter has a similar display of lights but of much greater size in comparison.
Electrically charged particles in the magnetosphere and solar radiation from the sun create a magnificent display of aurora borealis on Earth.
Similarly, solar storms cause huge auroras on Jupiter. But they glow much brighter than Earth because Jupiter’s tremendous size gives it more electrical potential.
It’s believed that Jupiter has 79 moons. Only 53 of the moons have names and 26 are awaiting for names.
They were all formed

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Retrieved Text: I'm into the Saturn System but perhaps some time periods have been ascribed to Saturnian times when they were Velikovskian times. One could expect a lot of memories of the old system to be expressed in the later times. If Earth was on an elliptical orbit that took it out to where Jupiter or even Saturn are now, then we could have very confusing Saturn and Jupiter stories in the Velikovsky time period.
If Amun was Venus then Amun-Re would surely be either when Venus approaches the Sun, the near conjunction being a very electrical time for the Earth, or there was a visible Birkeland current connecting Venus and the Sun.
Sorry about the Mercury, not the Moon, coming out of Mars. Still think that is very unlikely. But where did the Moon come from then ? Born from Jupiter. As I wrote before, the Moon is in equilibrium with it's plasma environment and this suggests the Moon was in this environment for a long time, so not born from Jupiter.
* Aten, I think Cardona, Talbott et al have developed the most plausible chronology of ancient history, which involves primarily the Saturn System. You seem to ignore the Saturn influence. Have you bothered to read about the Saturn Configuration at all? Much of what you say seems to contradict the Saturn theory and thus seems largely wrong.
What I think the problem is that Gary and maybe others have deciphered the Egyptian evidence and found references to Saturn and Jupiter that clearly have nothing to do with a Saturn

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Retrieved Text: Jupiter completes a rotation on its axis in about 10 hours.
The solar system has eight planets, which orbit around the sun. Out of the eight planets, six rotate around their axis in the same direction besides revolving around the sun. Jupiter is the fastest spinning planet while Venus is the slowest. Venus takes 243 Earth days to complete one rotation on its axis, making it the slowest of all planets. At the equator, Venus is spinning at the speed of 4.05 miles per hour compared to the Earth which spins at its equator at a speed of 1,037.6 miles an hour. Jupiter completes its rotation on its axis in about 10 hours, and its equator rotates at 28,273 miles an hour.
Jupiter is the 5th planet from the sun and it is the biggest of all planets in the solar system. It is a giant gaseous planet and about 2.5 times the size of all planets combined in the solar system. It spins on its axis in the opposite direction as opposed to most planets. Other gas planets include Saturn, Uranus, and Neptune. Jupiter is believed to have a solid core made of rocks. Like most other planets, Jupiter does not have a defined solid surface. As a result of its rotation, the planet has an oblate spheroid shape having a bulge along the equator. The atmosphere of the planet is divided into different bands that vary with the altitude. At the boundaries are great turbulence and storms and the popular one is the Great Red Spot;

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Retrieved Text: A Wikibookian suggests that this book or chapter be merged into Solar System.
From our small world we have gazed upon the cosmic ocean for thousands of years. Ancient astronomers observed points of light that appeared to move among the stars. They called these objects planets, meaning wanderers, and named them after Roman deities -- Jupiter, king of the gods; Mars, the god of war; Mercury, messenger of the gods; Venus, the goddess of love and beauty; and Saturn, father of Jupiter and god of agriculture. The stargazers also observed comets with sparkling tails, and meteors -- or shooting stars apparently falling from the sky.
Since the invention of the telescope, three more planets have been discovered in our solar system: Uranus (1781), Neptune (1846) and Pluto (1930). Pluto was reclassified as a dwarf planet in 2006. In addition, our solar system is populated by thousands of small bodies such as asteroids and comets. Most of the asteroids orbit in a region between the orbits of Mars and Jupiter, while the home of comets lies far beyond the orbit of Pluto, in the Oort Cloud.
The four planets closest to the sun -- Mercury, Venus, Earth, and Mars -- are called the terrestrial planets because they have solid rocky surfaces. The four large planets beyond the orbit of Mars -- Jupiter, Saturn, Uranus, and Neptune -- are called gas giants. Beyond Neptune, on the edge of the Kuiper Belt, tiny, distant, dwarf planet Pluto has a solid but icier surface than the terrestrial planets.
Nearly every planet -- and some

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Retrieved Text: Bollinger, C.J. (1952). A 44.77 year Jupiter-Earth-Venus configuration Sun-tide period in solar-climate cycles. Academy of Science for 1952 – Proceedings of the Oklahoma 307-311.
who illustrated the ~22 year JEV cycle over 60 years ago — see the configurations illustrated in Table 1 on p.308.
The dominant planetary gravitational force acting upon the outer convective layer of the Sun is that produced by Jupiter.
Other than Jupiter, the two planets that apply the greatest tidal forces upon the outer convective layer of the Sun are Venus and the Earth.
Periodic alignments of Venus and the Earth, on the same or opposite sides of the Sun once every 0.7997 sidereal Earth years, produces temporary tidal bulges on opposite sides of the Sun's surface layers (red ellipse in the schematic diagram above).
Whenever these temporary tidal-bulges occur, Jupiter’s gravitational force tugs upon these tidally-induced asymmetries and either slows down or speed-up the rotation rate of plasma near the base of the convective layers of the Sun.
It is proposed that it is the resultant variations in the rotation rate of the Sun’s lower convective layer, produced by the planetary tidal torquing of Venus, the Earth and Jupiter, that modulate the Babcock-Leighton solar dynamo. Hence, we claim that it is this modulation mechanism that is responsible for the observed long-term changes in the overall level of solar activity. In addition, this mechanism may be responsible for the torsional oscillations that are observed in the Sun's convective layer, as well.
It naturally produces a net increase in the rate of rotation of the outer layers of the

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Retrieved Text: Which Planet Has More Rings: Jupiter or Saturn?
Scientists still have a lot to learn about the vast, fascinating, mysterious zone around Earth they refer to as space. Space research discovers new facts about the cosmos all the time. One thing they do know is that there are eight primary planets in our solar system: Earth, Saturn, Jupiter, Uranus, Neptune, Mercury, Venus and Mars. (Pluto was demoted to a dwarf planet.) From Earth, you can see any of the other seven planets through a telescope. Four of these planets are known to have rings, but not all of the rings are made equally – Saturn stands out for having the largest and most impressive set.
Which Planet Has the Largest Set of Rings?
While all the so-called "giant" planets in our solar system – Saturn, Jupiter, Uranus and Neptune – have rings, none of them are as spectacular as Saturn's. Neptune has six known rings, and Uranus has 13 known rings. While scientists don't know for sure how many rings Saturn has, they believe it's in the region of 500 to 1,000. By contrast, only four rings have been identified around Jupiter.
Mercury, Venus and Mars have no rings.
Jupiter is named after the Roman god of the sky and thunder and is the fifth planet from the Sun. It is made of gas and covered in swirling clouds of ammonia and water. Although it doesn't have a solid surface, it may have a solid inner core about as big as Earth. Jupiter is famous for its Great Red Spot, a

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Retrieved Text: Use a steel ball rolling past magnets to model gravity assist (also called gravitational slingshot and swing-by), which is used to alter the path and speed of spacecraft in the solar system.
We have used rockets to send probes to many parts of the solar system, and beyond.
For sending spacecraft these long distances, we need to keep the fuel usage to a minimum, as much of the weight of a rocket is fuel (90%). Once rockets have used much fuel to escape earth’s gravity, we can use the gravity of the sun or other planets to alter the path and speed of a spacecraft, with minimal further fuel usage. Using the gravity of other bodies to change the speed and direction of a spacecraft is called “gravity assist”, “gravitational slingshot”, or “swing-by”, and has been used to send probes to the outer reaches of, and beyond, the solar system. The amount by which the spacecraft speeds up or slows down is determined by whether it is passing behind or in front of the planet as the planet follows its orbit.
Students will model gravity assist by rolling a steel ball (the "spacecraft") down a ramp onto a plexi sheet, which has a magnet (the "gravity" of a planet) in its path. The spacecraft is deflected by the gravity of the planet as it passes by. The amount of deflection depends on the speed of the spacecraft, how close it passes by the planet and the gravitational strength of the planet.
Draw a line down the centre of the plexi,

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Retrieved Text: NASA has revealed its final plans to crash the Cassini probe into Saturn next year.
Cassini–Huygens, to give the craft its full name, launched in 1997 and skipped past Venus twice and Earth once for some gravity-assisted acceleration action. It then grazed Asteroid 2685 Masursky, used Jupiter for acceleration and arrived at at Saturn on July 1st, 2004.
It's orbited ever since, clocking up 243 orbits, discovering ten moons and sending home 599GB of data that helped to fuel 3,616 scientific papers.
But the probe is now running out of fuel meaning NASA won't be able to control Cassini for much longer. It's therefore been decided to send the craft straight into Saturn because of the risk the craft may carry a terrestrial microbe that could damage the ecosystems it's speculated may exist on the gas giant's moons.
NASA's therefore started the year-until-death countdown for the probe, which will meet its fate on September 15th, 2017.
Cassini has a busy year to get through before dying. At present it's using Titan's gravity to raise its orbital tilt with respect to Saturn's equator and rings. From that position Cassini will be able to visit Saturn's “F rings” “kinked and braided”. Cassini's not had a good look at the F rings since 2004 and then only managed to see one side. This time around – or times, because the mission plans 20 orbits – the craft will get a very good look at the rings from a distance of just 7,800 kilometers.
The probe will then sneak between Saturn and the rings 22 times,

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Retrieved Text: As Earth and the various other planets and other bodies of the solar system travel on their respective orbits around the sun, it happens from time to time that, from our vantage point here on Earth, two (sometimes more) of the other planets (and/or other bodies) will lie along the same line of sight and appear close to each other in the sky. This apparent nearness to each other is simply an effect of viewing perspective, as the respective planets are usually at vastly different distances from us.
Such an event is usually called a conjunction.
Several nights last week featured one such conjunction taking place in our evening southern sky, slightly east of the head of the prominent constellation Scorpius. Shining fairly brightly slightly to the north of the bright star Antares is the red planet, Mars, and about 4 degrees – eight times the apparent diameter of the moon – to Mars’ north is the somewhat dimmer planet Saturn.
The fact that this conjunction is simply due to viewing perspective is underscored by the fact that, while Mars is currently just under 80 million miles from Earth, Saturn is over eleven times farther away, current distance just over 910 million miles.
Conjunctions such as these are always transitory. Both Mars and Saturn are traveling eastward relative to Scorpius, although Mars, being much closer, will rather rapidly leave Saturn and Antares behind over the next few weeks, while Saturn, being much more distant, plods along much more slowly.
An even more dramatic conjunction takes place this coming week, and involves

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Retrieved Text: The Solar System was formed approximately 4.6 billion years ago and consists of the Sun, planets, dwarf planets and other astronomical objects bound in its orbit. The formation was caused by the collapse of a giant molecular cloud, the mass at the centre collecting to form the Sun and a flat disk of dust around it which the planets and other bodies would eventually be formed from.
99.86% of the system’s mass is found in the Sun and the majority of the remaining 0.14% is contained within the solar system’s eight planets.
The four smaller inner planets, also known as the “terrestrial planets” (Mercury, Venus, Earth and Mars), are primarily composed of rock and metal.
The four outer planets, also known as the “Jovian planets” (Jupiter, Saturn, Uranus and Neptune), are substantially larger and more massive than the inner planets.
The two innermost gas giants, Jupiter and Saturn, are the larger of the four and are composed mainly of hydrogen and helium.
The two outermost gas giants, Uranus and Neptune, are composed largely of ices, (water, ammonia and methane) and are sometimes also referred to as the “ice giants“.
Other objects of note in the Solar System are the dwarf planets (Ceres, Pluto, Haumea, Makemake & Eris), moons, asteroids, the asteroid belt, comets and the Kuiper belt.
Compared with the billions of other stars in the universe, the sun is unremarkable. It holds the solar system together and pours life-giving light, heat and energy on Earth.
The first planet in our system was settled in 2034 by fearless men and women not afraid of

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Retrieved Text: A planet is a celestial body, directly orbiting a star, not sufficiently massive enough to generate photons in the range of visible light, but larger than a comet or asteroid. On both ends of the mass spectrum, it is a subjective call whether a body is a planet or not.
Planets can have atmospheres ranging from thick to none, and they can have lesser bodies orbiting them as satellites. The largest satellite (Ganymede) of the largest planet (Jupiter) is bigger than the smallest planet (Mercury). Humans have taken close-up photographs of all the planets in the Solar System with probes.
Pluto isn't a planet, however. Some people decided it, plainly and simply, sucked too much to be a legitimate planet. Sorry Hades.
The four rocky planets of our solar system.
A rocky planet, also called terrestrial planet is a planet made primarily of rock and often with metallic cores. According to theories on the development of solar systems and observations of our own, this is because heavier elements stay close to the centre of the solar system, close to the star, and form planets there. Rocky planets are one of two types of planets, the other being the Gas Giants where the atmosphere composes the majority of the planet's volume, rather than just a thin skin close to the surface. Rocky planets can also be classed as dwarf planets like Pluto when they're too small to be classed as actual planets.
In our solar system, the inner planets (Mercury, Venus, Earth and Mars) are rocky planets. The famous exoplanet Gliese 581c

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Retrieved Text: "Currently, vehicles are driving around on other planets to find out more about them, orbiters are circling almost every planet in our solar system and robotic probes are expanding our understanding of our own atmosphere and the magnetic field that protects Earth from radiation."
I am wondering about his statement that we have orbiters circling "almost every planet".
I am aware of probes around Mercury, Mars and Saturn and one on its way to Pluto (if you want to count it as a planet).
The book came out in 2013, so I assume it's fairly current.
It's oversimplified. There have been flybys of all planets, including Earth (for gravity assist in that case). As you mentioned, there will be a flyby of Pluto, now considered a dwarf planet. There are currently spacecraft in orbit around Mercury, Venus, Earth, Mars and Saturn, and there was an orbiter around Jupiter and will be another in 2016 (JUNO). Dawn will orbit a dwarf planet (Ceres) and has orbited an asteroid. There have also been various other interactions with other worlds and comets.
You know, looking at the chart, after ten years of travel, Rosetta doesn't seem to have moved al that much! Oh well, in the context of this thread, Churyumov-Gerasimenko isn't a planet.
I wasn't aware of Venus Express.
Still not quite "almost every planet" but no big deal. The book is otherwise informative and well written.

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Retrieved Text: Neither the Big nor the Little Dipper holds much water after nightfall in June; the Little Dipper stands on its handle while the Big Dipper hangs down by its own. But the Big Dipper’s handle makes a handy guide to stars and planets.
Follow its curve to Arcturus, the brightest star in the evening sky this month. Arcturus shines high in the south, anchoring the kite-shaped constellation Bootes, the herdsman. Continue the curve to Spica, in Virgo, and then turn to the east, where Jupiter reigns over dim Libra, the scales, a constellation that resembles a jellyfish. Next to Jupiter is Zubenelgenubi. Its ancient, Arabic-derived name refers to the southern claw of Scorpius and recalls a time when stars of Libra were considered a part of Scorpius. The scorpion and its red heart, Antares, rise low in the southeast and trail Jupiter into the sky.
Rising even later, Saturn glows above the Teapot of Sagittarius, the archer. On the 27th, Earth laps Saturn in the orbital race, and the planet will be up all night. Its glorious rings will be tipped to show a near-maximal amount of surface area, so if you have access to a telescope, this is a perfect time to have a look.
Trailing Saturn into the night sky, Mars brightens dramatically this month as Earth gains on it. Earth laps the red planet in the last week of July — an event not to be missed.
In the west, Venus continues to outshine everything else. On the 14th, a young crescent moon begins working its way

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Retrieved Text: Titan, the largest moon of Saturn, has a mean orbital radius of 1.22 x 109m. The orbital period of Titan is 15.95 days. Hyperion, another moon of Saturn, orbits at a mean radius of 1.48 x 109m. Use Kepler’s third law of planetary motion to predict the orbital period of Hyperion in days.
The mass of Earth is 5.97 x 1024 kg, the mass of the Moon is 7.35 x 1022kgand the mean distance of the Moon from the center of Earth is 3.84 x 105 km. Use these data to calculate the magnitude of the gravitational force exerted by Earth on the Moon.
Find the mass of the bowling ball.
Compare the weight of the first ball with the gravitational force exerted by the second ball.
The planet Mercury travels around the Sun with a mean orbital radius of 5.8 x1010m. the mass of the Sun is 1.99 x 1030 kg. Use Newton’s version of Kepler’s third law to determine how long it takes Mercury to orbit the Sun. Give your answer in Earth days.
Io, the closest moon to Jupiter, has a period of 1.77 days and a mean orbital radius of 4.222 x 108 m. Use this information together with Newton’s version of Kepler’s third law to determine the mass of Jupiter.
Earth has an orbital period of 365 days and its mean distance from the Sun is 1.495 x 108 km. The planet Pluto’s mean distance from the Sun is 5.896 x109 km. Using Kepler’s third law, calculate Pluto’s orbital period in Earth days.
The mass of Earth is

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Retrieved Text: The center of the Solar System is the Sun. The Solar System is made up of the Sun and all the planets, asteroids, and other objects that orbit the Sun.
There are eight planets in our Solar System. Starting with the closest to the sun they are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. The closest four planets (Mercury, Venus, Earth, and Mars) are termed terrestrial planets, meaning they have a hard rocky surface. The furthest four planets (Jupiter, Saturn, Uranus, and Neptune) are called gas giants. These planets are much larger and their surface is composed of gas elements (mostly hydrogen).
view of the solar system and the planets.
In addition to the Sun and the eight planets, there are other objects that are part of the Solar System.
Dwarf planets - Dwarf planets are objects similar to planets in the Solar System, however they are defined as not large enough to have "cleared their orbital region of other objects." Some of the dwarf planets in the Solar System include Pluto, Ceres, Eris, Haumea, and Makemake.
Comets - Comets are objects made of ice, dust, and rocks that orbit the sun. They often have a visible "tail" of gas that comes from solar radiation and solar wind. Comets originate from the Kuiper belt and the Oort cloud.
Asteroid belt - The asteroid belt is a region between the planets Mars and Jupiter. In this region thousands of rocky objects orbit the Sun. They range in size from tiny dust like particles to the dwarf planet Ceres.
Kuiper belt - The

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Retrieved Text: The planets very much affect the earth, indirectly, by having an effect on the Sun. Some planets are very large. If the Sun was a basketball the gas giants Jupiter and Saturn would be the size of grapeftuits, and the Earth would be, on that scale, the size of a peppercorn.
Jupiter and Saturn cause extra tides on the Sun when they get on either side of the Sun (as with Moon - Earth-Sun when the moon is full) and when these gas giants get on the same side as the Sun, (as with Earth -Moon - Sun when the moon is new). These greater solar tides become sunspot activity and solar flares and can be understood as akin to the increase in tides caused by the Moon when it too gets alongside Earth or opposite Earth.
and will continue until about May. In September the Earth was right in line with Jupiter, Saturn and the Sun too. That's why there were several 7+ earthquakes around, it wasn't just us. For instance there was one in Pakistan on the same day as Christchurch. This Jupiter/Saturn alignment continues until about May, and the Earth comes back into line as well in March. It is why there may be an extreme event, perhaps a large earthquake, around 20 March, which is when the Moon may be again in a trigger position.
and by the time November comes, Jupter/Saturn have moved away.
But for now, the moon moves closer until it is the closest in March. For now there are many solar flares.

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======= Instance Index 439 =========
Input Text: Read the passage below and choose the right answer to the following question (choices are greater or smaller ):

The more carbon atoms a hydrocarbon has, the greater the number of isomers.


If Jim is comparing hydrocarbons and he finds one that has less carbon atoms, the number of isomers that hydrocarbon contains is greater or smaller?

Target Text: smaller

#### Retrieved Documents ####

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Retrieved Text: The largest database1 of organic compounds lists about 10 million substances, which include compounds originating from living organisms and those synthesized by chemists. The number of potential organic compounds has been estimated2 at 1060—an astronomically high number. The existence of so many organic molecules is a consequence of the ability of carbon atoms to form up to four strong bonds to other carbon atoms, resulting in chains and rings of many different sizes, shapes, and complexities.
The simplest organic compounds contain only the elements carbon and hydrogen, and are called hydrocarbons. Even though they are composed of only two types of atoms, there is a wide variety of hydrocarbons because they may consist of varying lengths of chains, branched chains, and rings of carbon atoms, or combinations of these structures. In addition, hydrocarbons may differ in the types of carbon-carbon bonds present in their molecules. Many hydrocarbons are found in plants, animals, and their fossils; other hydrocarbons have been prepared in the laboratory. We use hydrocarbons every day, mainly as fuels, such as natural gas, acetylene, propane, butane, and the principal components of gasoline, diesel fuel, and heating oil. The familiar plastics polyethylene, polypropylene, and polystyrene are also hydrocarbons. We can distinguish several types of hydrocarbons by differences in the bonding between carbon atoms. This leads to differences in geometries and in the hybridization of the carbon orbitals.
Alkanes, or saturated hydrocarbons, contain only single covalent bonds between carbon atoms. Each of the carbon atoms in an alkane has sp3 hybrid orbitals and is bonded to four other

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Retrieved Text: The number of organic compounds, which are present around us and in our environment, is infinite. The large numbers are credited to the property of catenation as exhibited by carbon. Carbon can make four strong bonds; which, in turn, results in the formation of chain and ring structures. As the name indicates, hydrocarbons are organic compounds of hydrogen and carbon. Although the hydrocarbons are composed of only carbon and hydrogen, they occur in varied forms. This diversity can be attributed to the fact that hydrocarbons are present in the form of linear compounds, branched-chain structures, and ringed forms. The most common and the simplest hydrocarbon is methane. Hydrocarbons are versatile in their utility and are also present in crude oil, coal, natural gas, and other sources of energy; naturally.
Nonetheless, hydrocarbons never miss a chance to play a significant role in our daily life. The fuels that we use as sources of energy like CNG and LPG are nothing but a mixture of hydrocarbons only. Besides the uses mentioned above, the hydrocarbons render other great advantages as well. Let’s discuss the hydrocarbons in detail.
I. Saturated Hydrocarbons: The saturated hydrocarbons contain only carbon-carbon and carbon-hydrogen single bonds. They include open-chain as well as closed-ring structures. Alkanes and cycloalkanes are examples of saturated hydrocarbon; which are formed when different carbon atoms join to form an open-chain or a ringed structure.
II. Unsaturated Hydrocarbons: The unsaturated hydrocarbons contain multiple bonds; carbon makes double or triple bonds with other carbon atoms. The unsaturated hydrocarbons are of two types; alkene (containing double bonds)

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Retrieved Text: Hydrocarbon, an organic chemical compound composed of carbon and hydrogen. Hydrocarbons may be gases, liquids, or solids. In nature, they are found mainly in plants, petroleum, natural gas, coal, and oil shale. Most burn readily and dissolve more readily in alcohol than in water. Some are toxic and some form an explosive mixture with air. Hydrocarbons are used as fuels and solvents and in the manufacture of industrial chemicals, explosives, plastics, synthetic rubber, dyes, drugs, and other products.
More than 100,000 hydrocarbons are known. The main reason there are so many of these compounds is that carbon atoms can unite in many different ways to form complex chain or ring frameworks. Different arrangements of atoms yield different molecules. For example, the formula C30 H62 (30 carbon atoms and 62 hydrogen atoms) represents 4,111,846,763 possible isomers—compounds whose molecules differ only in structure.
In chemistry, compounds closely related in structure to hydrocarbons are called hydrocarbon derivatives. Such compounds consist of carbon, hydrogen, and other elements, usually oxygen, nitrogen, chlorine, phosphorus, or sulfur. They are often named for the hydrocarbons to which they are most closely related. For example, the organic chloride compound most closely related to ethane is called ethyl chloride. Hydrocarbons and their derivatives form a large part of the subject matter of organic chemistry.
Hydrocarbons are divided into two main groups according to structure—aliphatic (or acyclic) hydrocarbons and cyclic hydrocarbons. They are further divided into groups of compounds having similar chemical properties. Members within a group are called homologs, and each complete group is called a homologous series. Neighboring

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Retrieved Text: Crude oil, as it is taken from the earth, is a very complex mixture of hydrocarbons.
As might be expected, the term hydrocarbon refers to the hydrogen and carbon atoms linked together and forming a majority of the individual molecules that are present. Having been transformed from living organisms being subject to heat and pressure over millions of years, the crude is termed to be an “organic” material. In addition to hydrogen and carbon, there are small amounts of other atomic elements that are present and mostly incorporated into the hydrocarbon molecules. The most common of these are nitrogen and sulfur. As part of the hydrocarbon, they are referred to as “hetero-” atoms. Heavier crude may also contain some inorganic materials such as nickel, vanadium, and iron, which are removed during refining.
Hydrocarbons form in an extraordinarily large number of configurations. They range in size from the simplest methane molecule, which contains one carbon atom and four hydrogens, to heavy asphaltic resins with structures that have not been fully mapped. Because we are dealing with mineral oil–based lubricants, we are interested in molecules of a size that fit into the range of approximately 15 to 95 carbon atoms long, corresponding roughly to a boiling range of about 300–700°C. In addition, as the number of carbon atoms in a molecule increase, the number of different ways that a molecule can be structured increases dramatically. Although many different arrangements of molecules may be imagined, for practical purposes, petroleum hydrocarbons are generally classified in a limited number of ways.
Consider the list

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Retrieved Text: There are 5 lectures in this section of science wherein you are going to learn about Carbon and its compound. This is a very important chapter of Science and accounts for about 23 marks with periodic classification of elements. In Carbon and its compound You will learn the following as per the syllabus: Covalent bonding in carbon compounds. Versatile nature of carbon. Homologous series, Nomenclature of carbon compounds containing functional groups (halogens, alcohol, ketones, aldehydes, alkanes and alkynes), difference between saturated hydrocarbons and unsaturated hydrocarbons. Chemical properties of carbon compounds (combustion, oxidation, addition and substitution reaction). Ethanol and Ethanoic acid (only properties and uses), soaps and detergents.
This is first lecture of the Carbon and its compound which is the fourth chapter and is very important for SA-2 as it covers about 15-18 marks in exams. In this session you will learn about the Carbon and its properties. As you know carbon is an element and it has 4 valence electrons in its outermost shell, its valence electron are responsible for the entire change in the behavior and thus it forms maximum number of compounds. You will study here the terms covalency, catenation, tetravalency. The you will learn about the occurrence of Carbon. Sharing of electrons by Carbon. Then you will study the properties of hydrogen and how it forms compounds with hydrogen.Occurrence of allotropes of Carbon i.e.,Diamond, Graphite and Buckministerfulerene. You will study the properties of all three isotopes and difference among the three. You will also discuss the term Allotrophy, organic, Inorganic compound, saturated and

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Retrieved Text: Chapter L3 Section 4 Organic Compounds The Four Bonds of a Carbon Atom More than 90% of all compounds belong to a group called organic compounds. Organic compounds are covalent compounds composed of carbon-based molecules. Fuel, rubbing alcohol, sugar, cotton, paper and plastic belong to this group. All organic compounds contain carbon. Each carbon atom has four valence electrons so each carbon atom can make four bonds with four other atoms.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Carbon Backbones Structural formulas are models that are used to show how atoms in a molecule are connected. Each line represents a pair of electrons that form a covalent bond.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Many organic compounds are based on the types of carbon backbones shown below. Some compounds have hundreds or thousands of carbon atoms as part of their backbone.
Section 4 Organic Compounds The Four Bonds of a Carbon Atom, continued Organic compounds may also contain hydrogen, oxygen, sulfur, nitrogen, and phosphorus. The next slide shows three models of carbon backbones.
Section 4 Organic Compounds Hydrocarbons and Other Organic Compounds Many organic compounds contain several kinds of atoms, but some contain only two. Organic compounds that contain only carbon and hydrogen are called hydrocarbons. There are three types of hydrocarbons: saturated hydrocarbons, unsaturated hydrocarbons, and aromatic hydrocarbons.
Chapter L3 Section 4 Organic Compounds Hydrocarbons, continued Saturated Hydrocarbons An alkane, or saturated hydrocarbon, is a hydrocarbon in which each carbon atom in the molecule shares a single bond with

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Retrieved Text: This page deals briefly with the combustion of alkanes and cycloalkanes. In fact, there is very little difference between the two.
Complete combustion (given sufficient oxygen) of any hydrocarbon produces carbon dioxide and water. It is quite important that you can write properly balanced equations for these reactions, because they often come up as a part of thermochemistry calculations. Some are easier than others. For example, with alkanes, the ones with an even number of carbon atoms are marginally harder than those with an odd number!
With butane (C4H10), you can again balance the carbons and hydrogens as you write the equation down.
Counting the oxygens leads to a slight problem - with 13 on the right-hand side. The simple trick is to allow yourself to have "six-and-a-half" O2 molecules on the left.
The hydrocarbons become harder to ignite as the molecules get bigger. This is because the bigger molecules don't vaporize so easily - the reaction is much better if the oxygen and the hydrocarbon are well mixed as gases. If the liquid is not very volatile, only those molecules on the surface can react with the oxygen. Bigger molecules have greater Van der Waals attractions which makes it more difficult for them to break away from their neighbors and turn to a gas.
Provided the combustion is complete, all the hydrocarbons will burn with a blue flame. However, combustion tends to be less complete as the number of carbon atoms in the molecules rises. That means that the bigger the hydrocarbon, the more likely you are to get a

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Retrieved Text: A major class of organic compounds where carbon and hydrogen molecules are arranged in straight or branched chains. A type of hydrocarbon . Includes alkane s, alkene s, and alkyne s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where all of the carbon-carbon bonds are single bonds. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a double bond. One of three major classes of aliphatic hydrocarbon s.
An organic molecule containing carbon and hydrogen atoms in straight or branched chains, where at least one carbon-carbon bond is a triple bond. One of three major classes of aliphatic hydrocarbon s.
Molecules which are almost entirely carbon and hydrogen, but have had at least one chlorine atom introduced to them that has replaced one of their hydrogen atoms.
A hydrocarbon (molecule of carbon and hydrogen only) with 27 carbon atoms that is the parent structure of all mammalian steroid s.
Any of several enzyme s that put double bonds into the hydrocarbon areas of fatty acid s.
Any in a family of over 200 chlorinated organic chemicals (all heterocyclic hydrocarbons). The term is most commonly applied to a particular chemical, 2,3,7,8-tetrachlorodibenzo-paradioxin (2,3,7,8-TCDD, simply called TCDD), which is an impurity in the defoliant Agent Orange and in the pesticide 2,4,5-T (see auxin ). Dioxins are also produced when chlorinated materials such as plastics are burned. Dioxins are known to cause skin diseases (chloracne), birth defects, miscarriages, and cancer .
A

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Retrieved Text: The increasingly large number of organic compounds identified with each passing day, together with the fact that many of these compounds are isomers of other compounds, requires that a systematic nomenclature system be developed. Just as each distinct compound has a unique molecular structure which can be designated by a structural formula, each compound must be given a characteristic and unique name.
Such common names often have their origin in the history of the science and the natural sources of specific compounds, but the relationship of these names to each other is arbitrary, and no rational or systematic principles underly their assignments.
A rational nomenclature system should do at least two things. First, it should indicate how the carbon atoms of a given compound are bonded together in a characteristic lattice of chains and rings. Second, it should identify and locate any functional groups present in the compound. Since hydrogen is such a common component of organic compounds, its amount and locations can be assumed from the tetravalency of carbon, and need not be specified in most cases.
 A root or base indicating a major chain or ring of carbon atoms found in the molecular structure.
 A suffix or other element(s) designating functional groups that may be present in the compound.
 Names of substituent groups, other than hydrogen, that complete the molecular structure.
As an introduction to the IUPAC nomenclature system, we shall first consider compounds that have no specific functional groups. Such compounds are composed only of carbon and hydrogen atoms bonded together by sigma bonds (all carbons

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Retrieved Text: Covalent bond or Molecular bond or Homopolar bond : A chemical bond formed between two non-metallic elements by the mutual sharing of one or more electron pairs is called covalent bond.
Covalency : The number of electron pairs which an atom of an element mutually shares with another atom or atoms of the same or different elements, so as to acquire a stable configuration like noble gases, is called co valency.
Properties of covalent (molecular) compound : (i) They have low melting point and boiling point. (ii) They have low density, i.e., their density is generally less than that of water. (iii) They are gaseous or volatile liquids or soft solids. (iv) They are insoluble in water, but soluble in organic solvents. (v) They are generally bad conductors of electricity.
Diamond is the purest crystalline form of carbon which is the hardest naturally occurring substance.
Other pure crystalline forms of carbon are graphite and fullerenes. In Buckminster- fullerene, each molecule has 60 atoms arranged in hexagons and pentagons.
Organic Chemistry : The branch of chemistry dealing with carbon compounds other than carbon monoxide, carbon dioxide and carbonates is called organic chemistry.
Catenation : The property of carbon atoms to link with other carbon atoms or the atoms of other elements with single, double or triple covalent bonds, so as to form large number of compounds is called catenation.
Saturated organic compounds : Organic compounds in which all the four valencies of carbon atoms are satisfied by single covalent bonds, are called saturated organic compounds.
Unsaturated organic compounds : Organic compounds in which a double

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Retrieved Text: Cycloalkanes are named based on the number of C atoms in them, just like regular alkanes, but with the prefix cyclo- on the name. What are the names of the three smallest cycloalkanes?
Cycloalkenes are named similarly to cycloalkanes (see Exercise 1). What are the names of the cycloalkenes with five, six, and seven C atoms?
Draw the carbon backbone of all noncyclic alkanes with only four C atoms.
Draw the carbon backbone of all noncyclic alkanes with only five C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only four C atoms.
Cyclic alkanes can also have substituent groups on the ring. Draw the carbon backbone of all cyclic alkanes with only five C atoms.
Draw and name all possible isomers of pentene.
Draw and name all possible normal (that is, straight-chain) isomers of heptyne.
Polyunsaturated alkenes have more than one C–C double bond. Draw the carbon backbone of all possible noncyclic polyunsaturated alkenes with four C atoms and two double bonds. What are the complete molecular formulas for each possible molecule?
Draw the carbon backbone of all possible five-carbon cyclic alkenes with two double bonds, assuming no substituents on the ring.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between ethane and excess chlorine.
If a hydrocarbon is combined with enough halogen, all the H atoms will eventually be substituted with that halogen atom. Write the balanced chemical reaction between butane and excess bromine.
Molecules with multiple

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Retrieved Text: Propane is a fossil fuel and a component of natural gas. Over millions of years it formed from the organic remains of organisms and is mined from underground deposits. Propane gas is an organic compound made of three molecules of carbon atoms bonded with eight hydrogen atoms. The type of carbon-carbon carbon-hydrogen bonds determines the structure of propane molecules, which follows the same pattern as other types of natural gasses like methane and butane.
The chemical formula of propane is C3H8.
Propane is classified as an organic compound because it contains carbon. It is further categorized as a hydrocarbon because it belongs to a group of organic compounds that are made of only carbon and hydrogen. More specifically, propane is a type of hydrocarbon called an alkane. The atoms in alkane molecules are held together by single covalent bonds, and carbon atoms always form four covalent bonds.
Alkanes follow a general formula with a set ratio of carbon atoms to hydrogen atoms: C_nH2_n+2. The simplest alkane is methane, otherwise known as natural gas. It contains one carbon atom bonded to four hydrogen atoms. For methane, n = 1, so the number of hydrogen atoms it has is equal to 2(1)+2 which equals 4. Ethane contains two carbon atoms bonded together, and each carbon is bonded to three hydrogen atoms for a total of six hydrogen atoms. Propane has chain of three carbon atoms, with a chemical formula of C3H8, because a chain of three carbons require 2(3)+2 hydrogen atoms, which equals eight. Butane, another common alkane used as fuel

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Retrieved Text: Alkanes (also known as paraffins or saturated hydrocarbons) are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds (i.e., they are saturated compounds) without any cycles (or loops; i.e., cyclic structure). With the formula CnH2n+2, Alkanes belong to a homologous series of organic compounds in which the members differ by a constant relative molecular mass of 14. They have two main commercial sources: crude oil and natural gas.
Each carbon atom has 4 bonds (either C-H or C-C bonds), and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. The number of carbon atoms is used to define the size of the alkane (e.g., C2-alkane).
The simplest possible alkane (the parent molecule) is methane, CH4. There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon. Saturated oils and waxes are examples of larger alkanes where the number of carbons in the carbon backbone is greater than 10.
Alkanes are not very reactive and have little biological activity. Alkanes can be viewed as a molecular tree upon which can be hung the more biologically active/reactive portions (functional groups) of the molecule.

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Retrieved Text: Any organic compound composed only of carbon and hydrogen.
Any organic compound composed only of carbon and hydrogen. Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.
Because carbon atoms can form double and triple bonds, and chains and ring structures, this produces a huge variety of combinations. The simplest hydrocarbon molecules include methane, ethane, and propane. Like other hydrocarbons they are found in natural fossil fuel deposits, and are a major source of energy.

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Retrieved Text: Olefin content is an important factor in fuel production. But what exactly are olefins? In short, they’re an unsaturated hydrocarbon. Of course, there’s more to the story than that alone. Read on as we take a closer look at olefins – where they come from, what they’re made up of and why they’re important.
Olefin is a compound comprising hydrogen and carbon, with at least one pair of carbon atoms. Those atoms are linked by a double bond, which – along with the hydrogen and carbon content – makes them an unsaturated hydrocarbon.
Also known as alkene, olefins can vary in the number of double bonds per molecule, making them mono-olefins, diolefins, triolefins and so forth. They can also be categorised as either cyclic or acyclic. Cyclic olefins have a double bond between carbon atoms which makes up a closed ring of compounds. On the other hand, acyclic olefins form an open-chain group.
Where do olefins come from?
One of the earliest processes where olefins were produced came in the early 1900s through thermal cracking. This technique uses high temperatures and high pressure to break up large hydrocarbons into smaller compounds. They can also be produced by other forms of cracking, such as hydrocracking and fluid catalytic cracking.
Both petrol and diesel contain several different hydrocarbon molecules. Paraffins, olefins and aromatics account form most hydrocarbons in petrol, while diesel is mostly paraffins, aromatics and naphthenes.
Paraffins can improve the ignition quality of fuels, but can have low-termperature resistance. On the other hand, aromatics have high octane numbers – meaning the fuel can

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Retrieved Text: Scientists may possibly have found clues to what seems to be the path to forming life's building blocks in space.
Published in Nature Astronomy journal the new study reveals that lab experiments carried out by scientists to retrace the chemical steps leading to the creation of complex hydrocarbons in space, showing pathways to forming 2-D carbon-based nanostructures in a mix of heated gases. Scientists say their findings could help explain the presence of pyrene, which is a chemical compound known as a polycyclic aromatic hydrocarbon, and similar compounds in some meteorites.
Scientists explain that Pyrene has a molecular structure composed of 16 carbon atoms and 10 hydrogen atoms. Researchers found that the same heated chemical processes that give rise to the formation of pyrene are also relevant to combustion processes in vehicle engines, for example, and the formation of soot particles.
The latest study builds on earlier work that analyzed hydrocarbons with smaller molecular rings that have also been observed in space, including in Saturn's moon Titan - namely benzene and naphthalene.
Pyrene belongs to a family known as polycyclic aromatic hydrocarbons, or PAHs, that are estimated to account for about 20 percent of all carbon in our galaxy. PAHs are organic molecules that are composed of a sequence of fused molecular rings. To explore how these rings develop in space, scientists work to synthesize these molecules and other surrounding molecules known to exist in space.
For this study, researchers explored the chemical reactions stemming from a combination of a complex hydrocarbon known as the 4-phenanthrenyl radical, which has a molecular

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Retrieved Text: To describe the bonding in benzene and the way typical reactions of benzene differ from those of the alkenes.
Next we consider a class of hydrocarbons with molecular formulas like those of unsaturated hydrocarbons, but which, unlike the alkenes, do not readily undergo addition reactions. These compounds comprise a distinct class, called aromatic hydrocarbons, with unique structures and properties. We start with the simplest of these compounds. Benzene (C6H6) is of great commercial importance, but it also has noteworthy health effects.
The formula C6H6 seems to indicate that benzene has a high degree of unsaturation. (Hexane, the saturated hydrocarbon with six carbon atoms has the formula C6H14—eight more hydrogen atoms than benzene.) However, despite the seeming low level of saturation, benzene is rather unreactive. It does not, for example, react readily with bromine, which, is a test for unsaturation.

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Retrieved Text: Hydrocarbons containing at least three carbon atoms and non-aromatic carbon-to-hydrogen bonds are converted into hydrocarbons containing a new carbon-to-carbon linkage and having a higher carbon to hydrogen ratio by heating with an hydrogen-accepting olefine and a proportion of iodine (or hydrogen iodide, alkyl iodides or other compound which liberates iodine under the reaction conditions) of at least 0.05 mol. per mol. of hydrocarbon to be converted at at least 300 DEG C. to effect carbonto-hydrogen bond cleavage in the hydrocarbon feed and convert the olefine to paraffin. Conversions which may be effected are dehydrogenation of alkanes or aralkanes, e.g. isobutane to isobutene, n-butane to butenes and butadiene, ethyl benzene to styrene, o-methyl ethyl benzene to o-methyl styrene, and n-butyl benzene to 4 - phenyl - butadiene - 1,3; dehydrocoupling, e.g. propylene to diallyl, isobutene to dimethallyl, toluene to dibenzyl and stilbene; dehydrocyclization often with aromatization, e.g. n-hexane to benzene, n-heptane to toluene, n-octane to m-xylene and ethyl benzene, 2,5-dimethyl hexane to p-xylene, hexadiene-1,3 to benzene, hexane-1 to cyclohexene, o-diethylbenzene to naphthalene, o-methyl propyl benzene to naphthalene, n-butyl benzene to naphthalene, 2,3-diethyl naphthalene to anthracene, butylcyclohexane to naphthalene, and butylcyclopentane to indene; and dehydrogenation, often with aromatization of hydroaromatic hydrocarbons, e.g. cyclohexane to cyclohexene and benzene, and methylcyclohexane to toluene. In the case of acyclic hydrocarbons containing a quaternary carbon atom, dealkylation and/or isomerization may occur, e.g. 2,2,5-trimethylhexane gives p- and m-xylenes. The olefine used should be such that the sum of the standard free energy change for the hydrogenation of the olefine to the corresponding paraffin

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Retrieved Text: How is crude oil refined? What are the products it produces? Where does Australia sit in its ability to process crude oil? Not just now but in the future? Please view our animated infographic by clicking on the image below or click here to get the answers.
Crude oil, in its raw natural form, must undergo refinement to make it useful for consumers. An oil refinery separates, converts, and purifies the components of crude oil into valuable petrochemicals. Many products, from propane to petrol to bitumen, can come from just one barrel of crude oil through refining. Australian oil refineries were constructed in the 1950s and 1960s. Together, they have a refining capacity of approximately half a million barrels per day. Let’s look at the fundamental processes in an oil refining setup, and learn more about Australia’s role in the global oil industry.
The composition of crude oil varies greatly between different natural sources. The two most important factors for profiling crude oil are its density and its sulfur content.
Oil that is less dense is referred to as “light,” whereas denser oil is classified as “heavy.” Oil with high sulfur content is called “sour,” as opposed to “sweet” oil which contains less sulfur.
As hevay oil requires more refining than light oil to yield useful products, light oil is valued higher than heavy oil. For the same reason, oil that is sweet is more valuable than oil that is sour.
Most of the crude oil found in Australia is premium crude; light and sweet.
*Total litres exceed the volume of one

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Retrieved Text: Why Does Cholesterol Lower Membrane Permeability?
What Are the Functional Groups in Cholesterol?
Cholesterol fills such important roles that your body makes its own supply rather than depending on dietary sources. Two of its jobs -- making bile acids and creating the outer coating of cells -- rely on chemical structures in the cholesterol molecule called functional groups. While cholesterol is not soluble in water, within the molecule, one type of functional group is water-soluble and another is insoluble. It turns out this dual characteristic plays an essential role.
Molecules are made from atoms, which sometimes combine to form a specific group of atoms. These are called functional groups because they’re responsible for precise tasks in your body. Functional groups also define unique characteristics of a molecule. Cholesterol has two types of functional groups. The first one, called a hydrocarbon functional group, consists of atoms of hydrogen and carbon. In cholesterol, the hydrocarbons connect to form two different shapes -- rings and chains. The second group, called a hydroxyl group, contains one atom each of hydrogen and oxygen.
Four hydrocarbon rings form the middle of the molecule. This functional group is the same one found in steroid hormones synthesized from cholesterol. A chain of hydrocarbons extends from one side of the nucleus, creating a hydrocarbon tail. One hydroxyl group is connected to the opposite side of the nucleus. There is one important difference between the groups: Hydroxyl groups are soluble in water, while hydrocarbons are not water-soluble. A molecule that has soluble and insoluble regions is called amphipathic. This amphipathic

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Retrieved Text: 1.3.10 compounds with same molecular formula but different structural formula.Due to different chain length, they have different physical properties (e.g. boiling point). Isomerism can occur in both alkanes and alkenes.For alkene, double bond position can be changed.We therefore can’t just say that C6H14 is simply hexane because there are more variations of C6H14 and each variation has its own name.
1.6.2 small molecules (monomers) join together to form one molecule as the only product.
Crude oil is a mixture of complex hydrocarbons with varying boiling points, depending on the number of carbon atoms and how they are arranged.
Fractional distillation uses this property to separate the hydrocarbons in crude oil.
Naphtha fraction is used for production of petrochemicals, such as medicines, plastics and synthetic fibres, aside from fuels.
When naphtha is treated, not only it becomes a better fuel, it also contain more aromatic hydrocarbons, alkene and cyclic hydrocarbons which are important for petrochemical industry.
Crude oil is mostly used as fuel, though some allocated for chemical feedstock.
hydrocarbons which the combining capacity of the carbon atoms is as fully used as possible in bonding with hydrogen atoms.
They only have single bond (–) only.
hydrocarbons which the combining capacity of the carbon atoms is not fully used, e.g. only 2 or 3 hydrogen are attached to a carbon atom.
usually indicated by double bond (=) or triple bond with another carbon atoms.
Alkanes burn in air to ALWAYS form carbon dioxide and water.
When there is insufficient oxygen, the product is ALWAYS carbon monoxide and unburnt carbon.
Example: Butane is commonly used camping gas. State the chemical equation

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Retrieved Text: Having spent millions and millions of dollars surveying, exploring, appraising, designing, and developing a site, what do we have to show for it? This depends very much on the type of reservoir. ‘Oil and gas’ isn’t just one category (or even two), but covers a very broad range of mixtures defined by their chemical components.
From a commercial point of view, everything in oil or gas can be considered a hydrocarbon, an inert substance, or a contaminant. In the vast majority of reserves, hydrocarbons make up the vast majority of the mass and volume. This is just as well since they are the part we are most interested in. Hydrocarbons are, as the name implies, compounds made entirely of carbon and hydrogen, which come in an astonishing variety of shapes and sizes because of carbon atoms’ tendency to bond together in chains and rings.
The more common type of hydrocarbons is the aliphatic group, consisting of ‘chains’ and most types of ‘rings’. The simplest is methane, which is a gas has just one carbon atom and four carbon atoms. As we add carbon atoms in a line we get ethane, butane, propane, and pentane, all of which are gasses at room temperature; six carbon atoms make up the backbone of hexane, which is a liquid. These form a class of compounds called alkanes, which continue as you add more carbon atoms, forming increasingly viscous liquids and eventually solids (polythene is technically a very large alkane). Variants on the alkanes are the cycloalkanes, which are simple loops; alkenes and

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Retrieved Text: It’s well understood by physicists that stars are responsible for building most of the abundance of elements heavier than helium, through nuclear fusion. Recent observations from LIGO and optical counterparts of neutron star collisions indicate that these processes, and not supernovae, may be responsible for constructing certain elements such as gold and platinum.
But another considerable mystery is how complex chemistry occurs in outer space - how do these elemental building blocks meet and form complex hydrocarbons, like those that seem to be required for carbon-based life?
Now, new experiments have looked at conditions similar to those in outer space to assess the feasibility of processes to form a complex hydrocarbon molecule, pyrene. The study was an international collaboration between experimentalists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), astronomers from the University of Hawaii at Manoa, and theoretical chemists to understand the chemical reactions at Florida International University. The study was published March 5, in Nature Astronomy.
Hydrocarbons can include a vast array of different chemical compounds, due to the rich chemistry made possible by the hydrogenic bonding; molecular rings can form to provide a huge range of substances, many of which are used by biological organisms. Examples that have been detected in space include benzene and naphthalene. Pyrene is a slightly more complex molecule, consisting of 16 carbon atoms and ten hydrogen atoms; you can view it as four rings of benzene fused together. These polycylic aromatic hydrocarbons (PAHs) are considered possible precursors for the origin of life, and they are associated with the

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Retrieved Text: 23/03/2009 · 1. The problem statement, all variables and given/known data Name the structural isomers of C4H8Br2 and remember to number the carbon atoms …... All you have to do now is quickly draw out all the possible molecules that have five carbons and EITHER a ring or a double bond. You can't put both in there or you would be missing four carbons instead. Don't write out every C and H. Just use dots for the carbons, lines in between them for the bonds, and ignore the hydrogens. Shouldn't take much time at all.
23/03/2009 · 1. The problem statement, all variables and given/known data Name the structural isomers of C4H8Br2 and remember to number the carbon atoms … how to become a founder in monat 8/10/2015 · This video shows you how to draw the constitutional isomers of C4H10 such as butane and isobutane.
5/06/2008 · In the answers, it says there are only 2 structural isomers for butane. I thought it could be: butane, 1-methylpropane, ethylethane, or 1-2 methylethane ?

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Retrieved Text: Ethylene and acetylene are synonyms in the IUPAC nomenclature system for ethene and ethyne, respectively. Higher alkenes and alkynes are named by counting the number of carbons in the longest continuous chain that includes the double or triple bond and appending an -ene (alkene) or -yne (alkyne) suffix to the stem name of the unbranched alkane having that number of carbons. The chain is numbered in the direction that gives the lowest number to the first multiply bonded carbon, and adding it as a prefix to the name. Once the chain is numbered with respect to the multiple bond, substituents attached to the parent chain are listed in alphabetical order and their positions identified by number.
Compounds that contain two double bonds are classified as dienes, those with three as trienes, and so forth. Dienes are named by replacing the -ane suffix of the corresponding alkane by -adiene and identifying the positions of the double bonds by numerical locants. Dienes are classified as cumulated, conjugated, or isolated according to whether the double bonds constitute a C=C=C unit, a C=C―C=C unit, or a C=C―(CXY)n―C=C unit, respectively.
Double bonds can be incorporated into rings of all sizes, resulting in cycloalkenes. In naming substituted derivatives of cycloalkenes, numbering begins at and continues through the double bond.
Unlike rotation about carbon-carbon single bonds, which is exceedingly rapid, rotation about carbon-carbon double bonds does not occur under normal circumstances. Stereoisomerism is therefore possible in those alkenes in which neither carbon atom bears two identical substituents. In most cases, the names of stereoisomeric alkenes are

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Retrieved Text: Hydrocarbons and carbohydrates should not be confused. Hydrocarbons contain hydrogen and carbon only. Carbohydrates contain these two elements, but they also contain oxygen. In fact the "ate" suffix in chemistry implies oxygen. I'm sure you've heard of: carbonate (CO3), sulfate (SO4), phosphate (PO4), nitrate (NO3), and silicate (SiO4). These are not complete molecules - they are fragments, polyatomic anions to be precise, that are typically paired with metals to make salts or minerals, or with hydrogen to produce acids. Thus calcium carbonate, the principal component of limestone, or marble when compressed and heated over geologic time, is CaCO3. This "ate" nomenclature may help you remember that carbohydrates contain oxygen, and are a much more complicated molecule. In fact carbohydrates, along with proteins and fats, form the basis of food. These are the three macronutrients, as described earlier.
Since hydrocarbons contain only hydrogen and carbon, their structure is much simpler. In fact, the properties of a hydrocarbon molecule are determined, primarily, by the number of carbons. The simplest example has one carbon, surrounded by four hydrogens, and is called methane. It is a small, light, symmetric molecule, hence it is a gas. It does not liquify until -161C, or -258F. You've probably been out in weather that is subzero, but temperatures this cold are simply unimaginable.
The above representation is somewhat misleading, because it squashes the methane molecule onto the 2 dimensional page. Most molecules have a 3 dimensional structure. The carbon atom has four electrons in its outermost shell, four valence electrons, four bonds that must be satisfied.

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Retrieved Text: How Do You Calculate Number Of Isomers?
Where (n) is number of chiral carbon in compound?
Number of isomers are calculated using the no. Of carbon atoms in any compound. I think it is CnH4n-2 not valid for methane only.
To calculate isomers there are two methods: enumeration and counting. Finding the number of isomers in a given formula is called "counting." Finding the number of isomers, and all the individual elements of a formula is called "enumeration."
If you go to www.scctm.org./Awards/Ballard_Paper.pdf you will find a paper, which explains the calculation of numbers of isomers. Although, this article is chemistry specific, the first part of the article explains calculating the number of isomers.
On page 7 of the above paper you will find information about computerized calculations of isomers using enumeration. If you need to review isomers in general I suggest you go to www.chemistry-react.org/go/Tutorial/Tutorial_13027.html A site all about isomers. Just below the words, A creative look at Isomers, there is a green link. Click and you go to a new page Creative-Chemistry.org.uk Here you will find a simple definition of isomers, structural isomers, stereo isomers and more.
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How Do You Calculate 5% Of 8,648,459?
How To Do A Research Project?
Interview Question: Why Should I Hire You?
If y is inversely proportional to the square of x and y =1/9 when x =4, find y when x = 12?
I Need Some Multiple Choice Questions

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Retrieved Text: Naphtha is a flammable liquid mixture of hydrocarbons. It can be a component of natural gas condensate or a distillation product from petroleum, coal tar, or peat boiling. It is a broad term covering among the lightest and most volatile fractions of the liquid hydrocarbons in petroleum. Naphtha is a colorless to reddish-brown volatile aromatic liquid, very similar to gasoline.
In Petroleum Refinery Engineering, full range naphtha is defined as the fraction of hydrocarbons in petroleum boiling between 30°C and 200°C. It consists of a complex mixture of hydrocarbon molecules generally having between 5 and 12 carbon atoms. It typically constitutes 15–30% of crude oil, by weight. Light naphtha is the fraction boiling between 30°C and 90°C and consists of molecules with 5–6 carbon atoms. Heavy naphtha boils between 90°C and 200°C and consists of molecules with 6–12 carbons.
Naphtha is used primarily as feedstock for producing high octane gasoline (via the catalytic reforming process). It is also used in the bitumen mining industry as a diluent, the petrochemical industry for producing olefins in steam crackers, and the chemical industry for solvent (cleaning) applications. Common products made with it include lighter fluid, fuel for camp stoves, and some cleaning solvents. Light naphtha is also used directly as a blending component in the production of gasoline.

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Rank: 28
Score: 42.73737
Retrieved Text: L'analyse détaillée des distillats moyens est une étape indispensable à la compréhension des mécanismes réactionnels et à la cinétique de certains procédés de raffinage comme l'hydrotraitement. Une nouvelle méthode associant, d'une part un couplage chromatographie en phase gazeuse/spectrométrie de masse (CG/SM) et, d'autre part une analyse quantitative par famille chimique par spectrométrie de masse a été développée. La chromatographie en phase gazeuse, réalisée sur une colonne apolaire, effectue la distillation des composés présents dans le gazole et la spectrométrie de masse quantifie les familles chimiques par intervalle de nombre d'atomes de carbone ou de point d'ébullition. Elle permet d'accéder ainsi à la répartition par nombre d'atomes de carbone de chaque famille chimique (alcanes, cycloalcanes, hydrocarbures aromatiques à un ou plusieurs noyaux, hydrocarbures aromatiques soufrés). Cette méthode a été validée et appliquée à une charge et à une recette d'hydrotraitement.
A detailed analysis of middle distillates is essential for understanding the reaction mechanism and for studying the kinetics of refining processes such hydrotreatment. In fact, when we see the complexity of saturated and aromatic hydrocarbon mixtures appearing in gas oil, we realize that it's necessary to have a very detailed analysis of those cuts to understand the mechanisms involved in refining processes and to be able to describe their kinetics. Each gas oil has a very different composition and therefore a specific reactivity. That is why we have tried to develop predictive kinetic models to avoid experimenting in pilot plants, which is very expensive. But, even if all the compounds of a gasoline (PI-200°C) have now been identified

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Rank: 29
Score: 42.385914
Retrieved Text: Carbon is termed to be an element of enormous importance to us in both elemental and combined form. Food, clothes, medicines, books, and many of the things are based on this element carbon. Also all the living structures are carbon based. Only 0.02% carbon is found in earth’s crust. Carbon is found in minerals like hydrogen carbonates, carbonates, coal and petroleum. 0.03% of carbon dioxide is present in the atmosphere. Though it is available in very small amount, its importance is very large.
Most of the carbon compounds are found to be poor conductors of electricity. Carbon compounds have covalent bonds between them. Covalent bond is a bond that is formed by sharing an electron pair between two atoms. Carbon compounds behave as poor conductors of electricity because of the presence of covalent bond between them. Carbon atoms form covalent bonds between themselves and with the atoms of other elements also.
Allotropy is defined as the property of some chemical elements to exist in two or more different forms. The two different allotropes of carbon are diamond and graphite. In diamond, each carbon atom is bonded to other four carbon atoms forming a rigid 3-dimensional structure while in the case of graphite each carbon atom is bonded to other three carbon atoms in the same plane giving a hexagonal array.Fullerene is also an allotrope of carbon containing clusters of 60 carbons joined together to form a sphere (similar to the football) and this allotrope is also called as buckminsterfullerene.
1 - Carbon has the distinctive capability to form bonds

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