Question

Which of the following molecules has the lowest bond angle?

• A. $C{H}_4$
• B. $N{H}_3$
• C. $P{H}_3$
• D. $H_{2}O$

Answer 1

The correct option is C $P{H}_3$

A) $C{H}_4$ is $s{p}^3$ hybridized and has a regular tetrahedral structure with a bond angle of ${109}^{\circ }$.

B) $N{H}_3$ is $s{p}^3$ hybridized and it has pyrimidal shape. Due to lone pair-bond pair repulsions, the bond angle is reduced to ${107}^{\circ }$.

C) $P{H}_3$
According to Drago's rule it does not participate in hyrbidization and pure p-orbitals are involved in bonding and has a bond angle of ${93}^{\circ }$.

D) $H_{2}O$ is $s{p}^3$ hybridized and it has bent shape. Due to lone pair-lone pair repulsions and lone pair-bond pair repulsions, the bond angle is further reduced to ${104}^{\circ }$.