You already know why
phenols are more acidic than alcohols The higher acidity of carboxylic
acids as compared to phenols can be understood similarly The conjugate
base of carboxylic acid, a carboxylate ion, is stabilised by two equivalent
resonance structures in which the negative charge is at the more
electronegative oxygen atom The conjugate base of phenol, a phenoxide
ion, has non-equivalent resonance structures in which the negative charge
is at the less electronegative carbon atom