Electron pair repulsion
What Electron pair repulsion means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of Electron pair repulsion
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Reference: OCR
Every pair of electrons around a central atom acts as a charge cloud that pushes other pairs away, so the pairs spread out as far as possible.
Explains the shapes of molecules and ions by the number of electron regions around the central atom and how many are lone pairs.
Like charges repel, so the clouds push each other as far apart as they can, and the positions they settle into fix the shape.
Topics that use Electron pair repulsion
- Shapes of simple molecules and ions (AQA A-Level)
- Bonding and structure (OCR A-Level)
Related terms
- Anomalous melting and boiling points
- Average bond enthalpy
- Averaging over similar compounds and its limitation
- Bond angles
- bond length and strength
- Bond polarity and lone pairs
- Bond polarity versus molecular polarity
- Comparison of solid, liquid and aqueous states
Using Electron pair repulsion in the exam
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