Which have smallest bond angle? NH3 or N(CH3)3?

[kimiaUNY]

Hi guys, which of nh3 and N(CH3)3 have the smallest bond angle?

My answer is NH3, because H is smaller than CH3. so lone pair electron of N can easily push the H and make the bond smaller. Is this right?

 

[Evo]

Is this homework?

 

[Borek]

Definitely looks like one.

My answer is NH3, because H is smaller than CH3. so lone pair electron of N can easily push the H and make the bond smaller. Is this right?

More or less yes. Somehow I would prefer the explanation based on the term "steric effect".