Question

(i) Arrange the following in the increasing order of acidic strength and justify your answer.

CH₃COOH, CHCI₂COOH, CH₂CICOOH, CCI₃ COOH

(ii) Suggest a method to convert acetic acid to chloroacetic acid. Name the reaction and write the chemical equation.

Answer 1

(i) CH₃COOH < CH₂CI-COOH < CHCI₂COOH < CCI₃COOH 

This is due to the electron withdrawing character of chlorine.

(ii) HVZ reaction – When a carboxylic acid is treated with red P and halogen, the a-H atoms are successively replaced by halogen.

This reaction has great synthetic importance as the halogen atom can be replaced by a number of other groups giving useful products.