VSEPR theory — Science definition
Valence Shell Electron Pair Repulsion — the idea that electron groups around a central atom spread out as far apart as possible, which sets the molecule's shape.
Where it is taught
- Molecular Geometry & Polarity — Bonding, Formulas & Molecular Structure, Physical Science: Chemistry, Grade 11
In use
The tool chemists use to predict that shape from a simple Lewis structure is VSEPR theory, which stands for Valence Shell Electron Pair Repulsion — a long name for one commonsense idea.
Molecular Geometry & Polarity
Questions using vsepr theory
Problem 1
VSEPR theory predicts molecular shape based on the idea that the electron groups around a central atom…
- always stay at fixed 90° angles
- have no effect on the shape
- attract each other
- repel and spread as far apart as possible
Answer and explanation
repel and spread as far apart as possible
Electron groups are all negative, so they repel and spread out as far as possible, which sets the shape.
Problem 2
VSEPR theory is used to predict a molecule's…
- mass
- temperature
- color
- three-dimensional shape
Answer and explanation
three-dimensional shape
VSEPR predicts molecular shape from how electron groups repel and spread out.