in literature, find melting point and solubility in water of benzoic acid, vanillin, phthalic acid, salicyclic acids. Calculate the expected volume of hot water that would be requried to dissolve 0.15g of each compound. With info on melting point and solubility in water... how can you predict the amount of volume of water needed?? I know that you start by adding one drop and if it dissolves you add 10 drops more and if it doesn't dissolve you add 0.25ml more until it does dissolve... but how do you know how much to add if you're only given the melting point and the solubility?!?!?