SQA National 5 Chemistry Molecular shapes
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Valence shell electron-pair repulsion (VSEPR) theory are a set of rules which explain the geometry that molecules adopt. The rules are governed by finding the lowest energy conformation, holding both the bonding electrons and lone-pair electrons as far apart as possible.
The geometric shapes that molecules adopt have names and specific bond angles, which optimise electron repulsion to maintain the lowest energy configuration. The presence of lone-pairs of electrons can distort the geometry, due to their stronger electron repulsion.
There are some molecules whose geometries are assumed to be common knowledge. However, for unseen molecules it expected that their geometry can be determined using the VSEPR rules.
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