What is the effect of electron withdrawing group on the acidity carboxylic acid?
An electron withdrawing group increases the acidity carboxylic acid. It disperses negative charge by inductive/ resonance effect and stabilizes the carboxylate ion. Thus, p-nitro benzoic acid (pKa 3.41) is more acidic than benzoic acid (pKa 4.19). Nitro group is electron withdrawing group.