Question

Which of the following statement(s) would be incorrect about the following compound?

• A. All three $C-N$ bonds are of the same length
• B. $C_1-N$ and $C_3-N$ bonds are of the same length but shorter than the $C_5-N$ bond
• C. $C_1-N$ and $C_5-N$ bonds are of the same length but longer than the $C_3-N$ bond
• D. $C_1-N$ and $C_5-N$ bonds are of the same length but both are shorter than the $C_3-N$ bond

Answer 1

Answer: (A), (B), (D)

The correct options are
A All three $C-N$ bonds are of the same length
B $C_1-N$ and $C_3-N$ bonds are of the same length but shorter than the $C_5-N$ bond
D $C_1-N$ and $C_5-N$ bonds are of the same length but both are shorter than the $C_3-N$ bond

Due to the steric hinderance of three groups, the $-N{O}_2$ group go out of the plane with benzene ring and so conjugation of $-N{O}_2$ group with benzene is slightly diminished. So, $C_1-N$ and $C_5-N$ bonds are of same length but longer than $C_3-N$ bond