Question

Consider the molecules CH₄, NH₃ and H₂O. Which of the given statement is false?

Options

• The H-C-H bond angle in CH₄, the H-N-H bond angle in NH₃, and the H-O-H bond angle in H₂O are all greater than 90°.

• The H-O-H bond angle in H₂O is larger than the H-C-H bond angle in CH₄.

• The H-O-H bond angle in H₂O is smaller than the H-N-H bond angle in NH₃.

• The H-C-H bond angle in CH₄ is larger than the H-N-H bond angle in NH₃.

Answer 1

The H-O-H bond angle in H₂O is larger than the H-C-H bond angle in CH₄.

Explanation:

The bond angle in CH₄ is 109.5°, in NH₃ about 107°, and in H₂O about 104.5°. So, H-O-H angle is smaller than H-C-H, not larger. This trend is due to increasing lone pair–bond pair repulsions from CH₄ to H₂O.