Question

explain why the bond angle of ammonia is less than that of methane​

Answer 1

lone pair occupies more space (i.e., has stronger repulsion) than a hydrogen atom, so the lone pair-N-H bond angles are greater than the perfect 109.5o tetrahedral bond angles found in methane, and the H-N-H bond angles are compressed to less than 109.5o.The empirical H-N-H bond angles in ammonia are 107.8o

Answer 2

A lone pair occupies more space (i.e., has stronger repulsion) than a hydrogen atom, so the lone pair-N-H bond angles are greater than the perfect 109.5o tetrahedral bond angles found in methane, and the H-N-H bond angles are compressed to less than 109.5o. (The empirical H-N-H bond angles in ammonia are 107.8o.)

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