StreakPeaked· Practice

ExamsJEE MainChemistry

Rank the following resonance (canonical) structures of diazomethane in decreasing order of their contribution to the resonance hybrid: (a) CH2 = N+ = N- (b) -CH2 - N = N+ (c) +CH2 - N = N- (d) -CH2 - N+ (triple bond) N

  1. a > d > c > b
  2. b > a > c > d
  3. a > c > b > d
  4. d > a > b > c

Correct answer: a > d > c > b

Solution

Structure (a) CH2=N+=N- has the most favourable arrangement with octets satisfied and charges well placed, so it contributes most. Structure (d) -CH2-N+(≡)N places the negative charge on carbon but has a triple bond and complete octets, contributing next. Structures (c) and (b) are less favourable; (c) has separated charges with positive on carbon, while (b) is least stabilising. The accepted order is a > d > c > b.

Related JEE Main Chemistry questions

⚔️ Practice JEE Main Chemistry free + battle 1v1 →