The bond angle between two hybrid orbitals is $105^{\circ}$ Calculate the percentage of $s$ -character of hybrid orbital.

Question

Aicharya · Accepted Answer

$s$ -character $\propto$ bond angle
For $25 \% s$ character (as in $s p^{3}$ hybrid orbital), bond angle is $109.5^{\circ}$, for $33.3 \% s$ character (as in $s p^{2}$ hybrid orbital), bond angle is $120^{\circ}$ and for $50 \% s$ character (as in $s p$ hybrid orbital), bond angle is $180^{\circ}$. Similarly, when the bond angle decreases below $109.5^{\circ}$, the $s$ -character will decrease accordingly. Decrease in angle $=120^{\circ}-109.5^{\circ}=10.5^{\circ}$
Decrease in $s$ -character $=33.3-25=8.3$
Actual decrease in bond angle $=109.5^{\circ}-105^{\circ}=4.5^{\circ}$
Expected decrease in $s$ -character
$=\frac{8.3}{10.5} \times 4.5=3.56 \%$
Thus, the $s$ -character should decrease by about $3.56 \%$
i.e.,$s$ -character $=25-3.56=21.44 \%$

The bond angle between two hybrid orbitals is $105^{\circ}$ Calculate the percentage of $s$ -character of…

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