Which concept explains the shapes of molecules by repulsion of electron pairs?

• A. Hybridization
• B. Dipole
• C. VSEPR theory
• D. London dispersion forces

Answer: (C)

Electron pairs around a central atom arrange themselves to minimize repulsion, and this arrangement determines the molecule’s shape. This is described by VSEPR theory (Valence Shell Electron Pair Repulsion). In VSEPR, you count electron groups (bonding pairs and lone pairs) around the central atom and predict geometry from how those groups push on each other. Lone pairs take more space than bonding pairs, so they distort angles and shapes more, leading to real geometries that differ from the idealized ones. For example, two groups give a linear shape; three groups give trigonal planar; four groups give tetrahedral, with lone pairs causing shapes like bent or trigonal pyramidal in many common molecules. This concept stays focused on repulsion between electron pairs, rather than orbital mixing (hybridization) or intermolecular forces (dipole moments, London dispersion).