JAMB - Chemistry (2024 - No. 130)

The ammonia molecule is predicted to have a trigonal pyramidal or distorted tetrahedral shape by the valence shell electron pair repulsion (VSEPR) theory. The nitrogen atom at the center of the molecule has five electrons in its valence shell, three of which it shares with the three hydrogen atoms to form bonds. The remaining two electrons form a lone pair. The lone pair repels the bonding orbitals, which causes the molecule to have a distorted tetrahedral shape.

Consequently, The ammonia molecule (NH\(_3\)) has a trigonal pyramidal shape.