Chemistry - ALCOHOL & ETHER Question with Solution | TestHub

Question Explanation:

The question asks to compare the rate of acidic hydrolysis of ethers and identify which ether undergoes

cleavage most rapidly.

Concept Used:

This question is based on Substitution reactions of ethers, SN¹ mechanism, Carbocation stability

Solution:

Acidic hydrolysis of ethers (with HX) often proceeds via an SN¹ mechanism when a stable carbocation

can be formed.

Rate of SN¹ ∝ stability of the carbocation

A phenyl (aryl) group stabilizes a carbocation by resonance.

A para-methoxy (–OCH₃ ) substituent is a strong +M (electron-donating) group, which further

stabilizes the carbocation through resonance donation.

Replacing phenyl groups with p-methoxyphenyl groups therefore increases carbocation stability,

leading to a faster rate of ether hydrolysis

Thus two phenyl groups are replaced by two para-methoxyphenyl groups increases rate of reaction.