question_answer

Most stable carbocation among the following is

A)  

B)  

C)  

D)  All are equally

Correct Answer: A

Solution :

The stability of carbocation increases with increasing the number of alkyl groups attached to positively charged carbon atom or with increasing the number of hyperconjugative structures. Thus, \[{{1}^{o}}\] carbocation \[<{{2}^{o}}\] carbocation \[<{{3}^{o}}\] carbocation. Allyl and benzyl carbocation are stabilised by resonance. Hence,  is most stable because it is  \[{{3}^{o}}\] allylic carbocation.