Question

Which of the following species contains equal number of $\sigma$ and $\pi$ bonds?

• A. $Xe{O}_4$
• B. $(CN{)}_2$
• C. $C{H}_2(CN{)}_2$
• D. $HC{O}_3^{-}$

Answer 1

The correct option is A $Xe{O}_4$

Each double bond has one $\sigma$ and one $\pi$ bond. Each triple bond contains one $\sigma$ and two $\pi$ bonds.


The number of $\sigma$ and $\pi$ bonds are given below:

Molecule	Number of $\sigma$ bonds	Number of $\pi$ bonds
$Xe{O}_4$	4	4
$(CN{)}_2$	3	4
$C{H}_2(CN{)}_2$	6	4
$HC{O}_3^{-}$	4	1

Thus, $Xe{O}_4$ contains equal number of $\sigma$ and $\pi$ bonds.

Hence, option (a) is correct.