Question

Rank the following compounds in order of increasing acidity (weakest acid first).

• A. $2<3<1$
• B. $3<1<2$
• C. $1<2<3$
• D. $2<1<3$

Answer 1

The correct option is D $2<1<3$

The phenoxide ion (which is formed after the removal of proton from phenol) is stabilized by presence of electron withdrawing group. More the electron withdrawing effect, more it will be stabilized and consequently more will be its acidic strength. On the other hand, electron - donating groups decreases its acidic strength.
Hence, the order of acidic strength will be $2<1<3$.