question_answer

                Which one of the following alkenes will react faster with H2 under catalytic hydrogenation conditions?

A)                                                                                                                                                                                             

B)                

C)                

D)                

Correct Answer: A

Solution :

                Stability of alkene: \[\propto \,\,\frac{1}{Heat\,of\,hydrogenation\,of\,alkene}\]                 Greater the number of alkyl groups attached to the doubly bonded carbon atoms, more stable is the alkene. Hence, given alkene   follow the following order of stability.                                 Hence, faster hydrogenation in                                 (R = Alkyl substituent)