Which of the following correctly arranges the acids in decreasing order of acidity? (pKa: CH3COOH 4.76, ClCH2COOH 2.86, Cl2CHCOOH 1.29, Cl3CCOOH 0.65)

Cl3CCOOH > Cl2CHCOOH > ClCH2COOH > CH3COOH

ClCH2COOH > Cl2CHCOOH > Cl3CCOOH > CH3COOH

Cl3CCOOH > Cl2CHCOOH > ClCH2COOH > CH3COOH

Cl2CHCOOH > Cl3CCOOH > ClCH2COOH > CH3COOH

CH3COOH > ClCH2COOH > Cl2CHCOOH > Cl3CCOOH

JEE Main levelSingle correct optionDifficulty 2 of 3co178

Which of the following correctly arranges the acids in decreasing order of acidity? (pKa: $CH X_{3} COOH$ 4.76, $ClCH X_{2} COOH$ 2.86, $Cl X_{2} CHCOOH$ 1.29, $Cl X_{3} CCOOH$ 0.65)

A lower pKa means a stronger acid. Each additional chlorine adds a

- I

effect that stabilises the carboxylate, so the order of pKa is 0.65 < 1.29 < 2.86 < 4.76.