Question

Which one of the following has the smallest bond angle ?

• A. $NH_3$
• B. $BeF_2$
• C. $H_2O$
• D. $CH_4$

Answer 1

Answer: (C)

$H_2O$

Answer 2

Hybridisation involved in $NH_3$ is $sp^3$ with one lone pair, in $BeF_2$ is $sp^2$ with no lone pair, in $H_2O$ is $sp^3$ with two lone pairs, in $CH_4$ is $sp^3$
with no lone pair, in $S O_2$ is $sp^1$ with one lone pair. Therefore, least bond angle is $H_2O$ (= 104-5$^\circ$).