A molecule with three bonded pairs and one lone pair has what type of geometry?

A molecule with three bonded pairs and one lone pair adopts a pyramidal geometry. This occurs because, according to VSEPR (Valence Shell Electron Pair Repulsion) theory, the presence of lone pairs affects the shape of the molecule. The three bonded pairs will arrange themselves in a way that maximizes the distance between them, creating a tetrahedral arrangement if there were no lone pairs.

However, the lone pair occupies one of the tetrahedral positions, causing the remaining three bonded pairs to be pushed closer together. As a result, the shape of the molecule is modified to a trigonal pyramidal structure, where the bonded atoms form the base of a pyramid and the lone pair is situated at the apex. This is characteristic of molecules like ammonia (NH₃), which also exhibit this pyramidal geometry due to the influence of the lone pair.