Practice question · Multiple choice
Water and methane both have four electron domains around the central atom, yet their bond angles are and . Why?
Hints
- Both have four domains, so the difference must come from the KIND of domain.
- A lone pair is held by one nucleus only and spreads wider than a bonding pair.
Show the answer
B. Water’s two lone pairs repel more strongly than bonding pairs and compress the angle
Why
A lone pair is bound to a single nucleus and occupies more angular space than a shared pair. Water’s two lone pairs squeeze the H-O-H angle below the ideal tetrahedral value; methane, with none, keeps it.
Practise Molecular Geometry and Polarity
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