How to Calculate Molecular Geometry
What is Molecular Geometry?
VSEPR theory predicts molecular geometry from electron domains: electron-pair repulsion minimizes; determines molecular properties.
Step-by-Step Guide
- 1Input central atom and bonding
- 2Count bonding + lone pair electron domains
- 3Predict geometry and bond angles
Worked Examples
Input
H₂O: C = 2 bonds + 2 lone pairs = 4 domains, tetrahedral electron domain, bent molecular, 104.5° angle
Result
Polar molecule due to bent geometry
Common Mistakes to Avoid
- ✕Confusing electron domain geometry with molecular geometry
- ✕Not counting lone pairs
Frequently Asked Questions
Why do lone pairs matter?
Lone pairs occupy more space than bonds; repel more strongly, affecting bond angles.
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