Understanding VSEPR Theory in Chemistry

VSEPR (Valence Shell Electron Pair Repulsion) theory is a model used in chemistry to predict the three-dimensional

shape (molecular geometry) of molecules based on the principle that electron pairs in the valence shell

of a central atom will arrange themselves to be as far apart as possible to minimize repulsion.

To use the theory, one must first draw the Lewis structure, then count the total number of electron

groups (both bonding pairs and lone pairs) around the central atom, and finally,

use this information to determine the electron-group geometry and the resulting molecular geometry.