Chemistry - GOC Question with Solution | TestHub

Removing ${\mathrm{H}}_1$ gives the phenoxide :

Removing ${\mathrm{H}}_2$ gives the carboxylate :

Both charges are on oxygen, so compare resonance quality : the carboxylate shares the charge equally over two oxygens, while the phenoxide pushes the charge onto ring carbons, which are less electronegative. The carboxylate is more stable, so the carboxylic O-H proton ${\mathrm{H}}_2$ is more acidic.