Identify the correct order of acidic strength for the following compounds: (i) (ii) (iii)

Step-by-step solution

Compounds (i) and (iii) are carboxylic acids, whereas compound (ii) is a phenol. Carboxylic acids are significantly more acidic than phenols because the carboxylate anion is highly stabilized by two equivalent resonance structures. Therefore, both (i) and (iii) are more acidic than (ii). Comparing the carboxylic acids, compound (i) is 2,6-di-tert-butylbenzoic acid and compound (iii) is benzoic acid. In compound (i), the presence of two bulky tert-butyl groups at the ortho positions forces the carboxylate group out