{"knowledge_schema": {"broad_category": "Chemistry \u2192 Solutions \u2192 Concentration Calculations", "refinement": "This problem involves calculating the concentration of a specific ion (orthophosphate) in a solution containing two phosphate salts.", "specific_scope": "The focus is on determining the concentration of orthophosphate ions (PO4^3-) in a solution made from KH2PO4 and Na2HPO4\u25cf2H2O, considering the dissociation of these compounds and the equilibrium constants of phosphoric acid.", "goal": "Calculate the concentration of orthophosphate ions in the solution based on the given masses of the salts and their molecular weights."}, "summary": "This problem is centered around calculating the concentration of orthophosphate ions in a solution containing two phosphate salts. It requires understanding the dissociation of these salts in water and applying the equilibrium constants for phosphoric acid to find the concentration of the orthophosphate ions. The goal is to determine the concentration in molarity (M) based on the provided masses and molecular weights of the compounds."}