At the molecular level, solubility is controlled by intermolecular forces. However a simple, empirical rule “like dissolves like” and it is based on the polarity of the systems i.e. polar molecules dissolve in polar solvents (e.g. water, alcohols) and non-polar molecules in non-polar solvents (e.g. the hydrocarbon hexane). This is why ionic compounds like table salt (sodium chloride) or compounds like sugar, dissolve in water do not dissolve to any great extent in most organic solvents. The polarity of organic molecules is determined by polar bonds1 due to the presence of electronegative atoms (e.g. N, O) in polar functional groups such as amines (-NH2) and alcohols (-OH). Water-soluble organic compounds include organic anions, dicarboxylic acids, oxo acids, dicarbonyls, carbohydrates, amino acids, aliphatic amines, urea, and some miscellaneous multifunctional compounds containing multiple hydroxy, carboxyl, and carbonyl groups (e.g. glyceraldehyde, malic acid, citric acid, lactic acid, and tartaric acid). Lower molecular weight compounds with polar functional groups are the most water soluble. Methanol (CH3OH), ethanol (CH3CH2OH) and isopropanol ((CH3)2CHOH) are a few examples of low molecular weight alcohols that are completely miscible with water. Dimethylamine, HN(CH3)2 and acetic acid, CH3COOH, are two more examples of organic compounds that are soluble in water.   _{Your Comment}