{"knowledge_schema": {"broad_category": "Chemistry \u2192 Organic Chemistry \u2192 Spectroscopy", "refinement": "This problem involves interpreting 13C NMR data to identify an organic compound based on its chemical shifts.", "specific_scope": "The task is to analyze the provided chemical shifts in relation to known compounds to determine which one matches the data.", "goal": "Identify the unknown organic compound from the given options based on the 13C NMR chemical shifts."}, "summary": "In this problem, we are tasked with identifying an unknown organic compound using 13C NMR data, which provides information about the carbon environments in the molecule. The chemical shifts given (170.0, 135.0, 128.0, 20.0 ppm) suggest the presence of specific functional groups and structural features. By comparing these shifts to the known compounds\u2014Methyl acrylate, Ethyl acetate, Methyl methacrylate, and Ethyl acrylate\u2014we can deduce that the unknown compound is Methyl acrylate, as its chemical shifts align with the expected values for this compound."}