MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

Acidic strength is directly proportional to the stability of the conjugate base. Electron-withdrawing groups (-I effect) stabilize the carboxylate ion and increase acidic strength, while electron-donating groups (+I effect) destabilize the carboxylate ion and decrease acidic strength. The +I effect of the isopropyl group ( CH _3)_2 CH - is greater than that of the methyl group CH _3-. Chlorine atoms exert a -I effect, which increases acidic strength. Thus, Cl _3 CCOOH and ClCH _2 COOH are stronger acids. Since ( CH _3)_2 CH - has the maximum +I effect among the given groups, it destabilizes the conjugate base the most, making ( CH _3)_2 CHCOOH the weakest acid. Answer: ( CH _3)_2 CHCOOH