short answers please

2. Chemistry a. The pKa of salicylic acid is 2.97 while that of benzoic acid is 4.19. Why is salicylic acid a much stronger acid than benzoic acid? (it is not enough to say, because the pKa is lower...) (4 pts) b. How do you account for the smell of vinegar when you open an old bottle of aspirin. Write a reaction scheme as a part of your answer. 3. Crystallization At the end of a crystallization, where should the impurities be located? ( 4 pts) 4. Melting Point Why is the melting "point" of a substance actually a melting "range" and therefore should never be recorded as a single temperature? (4 pts)