Correct order of the following acids in order of their increasing acidic strength is
(A) $CCl_3COOH$
(B) $ClCH_2COOH$
(C) $CH_3COOH$
(D) $CHCl_2COOH$
Choose the correct answer from the options given below: Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (C), (B), (D), (A)
Acidic strength of carboxylic acids increases with the electron-withdrawing (–I) effect of substituents on the α-carbon. More chlorine atoms → stronger −I effect → greater stabilization of the conjugate base → stronger acid.
Given acids:
- (C) CH₃COOH (no Cl) → weakest
- (B) ClCH₂COOH (one Cl)
- (D) CHCl₂COOH (two Cl)
- (A) CCl₃COOH (three Cl) → strongest
Increasing order of acidic strength: CH₃COOH < ClCH₂COOH < CHCl₂COOH < CCl₃COOH
that is (C), (B), (D), (A)