Question

How will u convert malic acid into tartaric acid and.....?

Answer 1

First the treat the malic acid with conc $\ce {H_2SO_4} $ and heat it. The $\ce {OH} $ group will leave the molecule and , also a molecule of water from two carboxylic acid group and an acid anhydride will form, so, in the first step.,i.e Maleic anhydride will form. Then do hydrolysis to form Maleic Acid and then addBayer"s reagent(cold alkaline $\ce {KMnO_4}$) and thus you will have Tartaric acid ( meso -tartaric acid). If you want to have optically active Tartaric acid, use epoxide induced Hydrolysis.