Identify the correct order of acidic strength for the following compounds: (I) (II) (III)

Step-by-step solution

The acidic strength of benzoic acid derivatives depends on the stability of the carboxylate anion formed after losing a proton. In compound (III) (benzoic acid), there is no extra stabilization of the conjugate base other than resonance with the benzene ring. In compound (II) (salicylic acid or 2-hydroxybenzoic acid), the conjugate base is stabilized by intramolecular hydrogen bonding between the ortho-hydroxyl group and the carboxylate oxygen. This makes it significantly more acidic than benzoic acid (III). In com