Question

With respect to the compounds I-V, choose the correct statement(s).

(A) The acidity of compound I is due to delocalization in the conjugate base. 

(B) The conjugate base of compound IV is aromatic. 

(C) Compound II becomes more acidic, when it has a -NO₂ substituent. 

(D) The acidity of compounds follows the order I > IV > V > II > III.

Answer 1

Answer: (A,B,C)

(C) –NO₂ is –I group (electron withdrawing group). It increases acid strength. 

(D) Acid strength order : IV > V > I > II > III