How does vsepr theory classify molecules?
Valence shell electron pair repulsion theory (vesper for short) classifies molecules on the basis of the number of electron pairs, bonding and lone pairs, associated with the central atom.
It is a fact that electron pairs arranged around a central atom repel each other (hence vesper). In the molecule, they assume a shape, a geometry, that will minimize electronic interaction. These shapes can correspond to the Platonic solids: 2 pairs, linear; three pairs, trigonal planar; 4 pairs, tetrahedral; 5 pairs, trigonal pyramidal; 6 pairs, octahedral.
Sometimes, this geometry is not readily apparent. There are 4 electron pairs around the central oxygen atom in water,
So the ideal
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