Question

The maximum s-character is exhibited by the orbitals of which central atom?

• A. $C{H}_4$
• B. $Xe{O}_3$
• C. $Xe{O}_6^{4-}$
• D. $S{F}_4$

Answer 1

The correct option is A $C{H}_4$

The hybridisation on C in $C{H}_4$ is $s{p}^3$ - each hybrid orbital shows 25% s-character.
In $Xe{O}_3$ also, the hybridisation is $s{p}^3$ (but has pyramidal shape with bond angle < 109.5 ${}^{\circ }$), so that we expect 25% s-character for each hybrid orbital.
But % s-character depends on the bond angle$\left(\theta \right)$.
$cos\theta =\frac{s}{s-1}$
$s-character\propto bondangle$
Thus, hybrid orbitals of $C{H}_4$ will be having more s-character.
The hybrid orbitals of $Xe{O}_6^{4-}$ having $s{p}^3{d}^2$ hybridisation shows approximately 16.7% s-character. $S{F}_4$ having $s{p}^{3}d$ hybrid orbitals will show approximately 20% s-character.