Question

The acidic hydrolysis of ether (X) shown below is fastest when

A. one phenyl group is replaced by a methyl group
B. one phenyl group are replaced by a para-methoxyphenyl group
C. two phenyl groups are replaced by two para-methoxyphenyl groups
D. no-structural change is made to X

Answer 1

Correct Answer - C
The acid hydrolysis preeeds by `S_(N^(1))` mechanism in which a carbocation intermediate is formed . The ease of hydrolysis or the rate of reaction depends upon the stability of the carbocation intermediate. The p-methoxyphenyl `(pCH_(3)O)C_(6)H_(5)`-group because of its greater electron releasing nature stabilises the carbocation intermediate more than the phenyl group.

Therefore ,(c) is the correct option.