This topic explains how the Valence Shell Electron Pair Repulsion (VSEPR) Theory is used to determine the shapes and bond angles of molecules.
Definition
VSEPR Theory: Valence Shell Electron Pair Repulsion Theory — a model used to predict the shape of molecules based on the repulsion between electron pairs around the central atom.
Main Idea
Electrons are negatively charged, so electron pairs around a central atom repel each other. The shape of a molecule is determined by the arrangement that minimizes these repulsions. The shape depends on the number of bonding pairs and lone pairs around the central atom. Lone pairs occupy more space than bonding pairs, so they affect bond angles.
Core Concept
Electron pairs around a central atom arrange themselves as far apart as possible to minimize repulsion.
