Question

Consider the molecules $ CH_4, NH_3$ and $H_2O$. Which of the given statements is false?

• A. The $H - O - H$ bond angle in $H_2O$ is larger than the $H - C - H$ bond angle in $CH_4$
• B. The $H - O - H$ bond angle in $H_2O$ is smaller than the $H - N - H$ bond angle in $NH_3$
• C. The $H - C - H$ bond angle in $CH_4$ is larger than the $H - C - H$ bond angle in $NH_3$
• D. The $H - C - H$ bond angle in $CH_4$ , the $H - N - H$ bond angle in $NH_3$, and the $H - O - H$ bond angle in $H_2O$ are all greater than $90^{\circ}$

Answer 1

Answer: (A)

All the three molecules are $sp ^3$ hybridised but the bond angles are different due to the presence of lone pair. The bond angle of $H _2 O$ is $104.5^{\circ}$ due to bond pair - lone pair repulsion and the bond angle of $CH _4$ is $109.25^{\circ}$.