AllChemicals — The Online Chemical Glossary | https://allchemicals.info/chemical/380-electron-pair-repulsion
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Quick Reference
Also Known As
VSEPR (Valence Shell Electron Pair Repulsion), electron pair geometry
What is Electron Pair Repulsion?
The basis of VSEPR theory, which states that electron pairs around a central atom arrange themselves to minimize repulsion. Lone pairs repel more strongly than bonding pairs, influencing molecular geometry. This theory predicts the shapes of molecules.
Properties & Characteristics
Electron pair repulsion is the principle underlying VSEPR (Valence Shell Electron Pair Repulsion) theory: all electron pairs in the valence shell of a central atom repel each other and arrange themselves to minimise repulsion. Lone pairs repel more strongly than bonding pairs (LP-LP > LP-BP > BP-BP). This arrangement determines molecular geometry. For example: 4 BP → tetrahedral (109.5°); 3 BP + 1 LP → trigonal pyramidal; 2 BP + 2 LP → bent.
Uses & Applications
VSEPR is used to predict molecular shapes without detailed quantum mechanical calculations. It explains geometries of water (bent), ammonia (pyramidal), methane (tetrahedral), SF₆ (octahedral), and PCl₅ (trigonal bipyramidal), which determine polarity, reactivity, and biological activity.
Safety Information
Molecular geometry determines toxicity and biological action. Knowing the shape of toxic molecules (nerve agents are tetrahedral at phosphorus, fitting enzyme active sites) aids in designing antidotes and protective equipment.
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
SynonymsVSEPR (Valence Shell Electron Pair Repulsion), electron pair geometry
Frequently Asked Questions
The basis of VSEPR theory, which states that electron pairs around a central atom arrange themselves to minimize repulsion. Lone pairs repel more strongly than bonding pairs, influencing molecular geometry. This theory predicts the shapes of molecules.
VSEPR is used to predict molecular shapes without detailed quantum mechanical calculations. It explains geometries of water (bent), ammonia (pyramidal), methane (tetrahedral), SF₆ (octahedral), and PCl₅ (trigonal bipyramidal), which determine polarity, reactivity, and biological activity.
Molecular geometry determines toxicity and biological action. Knowing the shape of toxic molecules (nerve agents are tetrahedral at phosphorus, fitting enzyme active sites) aids in designing antidotes and protective equipment.
Editorial standards: Chemical data is sourced from peer-reviewed literature,
CAS Registry, NIST WebBook, and PubChem. Safety information reflects guidance from OSHA, ECHA,
and IAEA. For educational purposes only — always consult official SDS documentation and qualified
professionals before handling chemicals.
