Question

Pyridine has 6 bonding ( $\pi$ ) and 2 nonbonding electrons, which statement is true regarding resonance in pyridine?

• A. All of these electrons are involved in resonance
  
  
• B. $4\pi$ and 2 non-bonding electrons are involved in resonance
  
• C. Only $6\pi$ electrons are involved in resonance
  
• D. Any of the 6 electrons

Answer 1

The correct option is C

Only $6\pi$ electrons are involved in resonance

Refer the molecular orbital structure of pyridine where the six $\pi$ electrons are derived from p orbitals lying parallel to each other, while the two nonbonding electrons on N belong to $s{p}^2$ orbital which lies perpendicular to the ring.