VSEPR

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VSEPR

• Valence-Shell Electron-Pair Repulsion Theory

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• The electron dot structures are not flat 2D
  stuctures, they are 3D in real life
• Electron pairs repel

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• Molecules adjust their shapes so that the valance
  electron pairs are as far apart as possible

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Tetrahedral109.5 degreesExample CH4
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PyramidalUnshared pair strongly repels the
covalent bonding pairs, pushing them closer
together. All angles are 107 degreesExample NH3
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Bent TriatomicUnshared pairs strongly repel the
covalent bonding pairs. All angles are 105.
Example H2O
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Linear triatomicAngles are 180 degreesExample
CO2
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Trigonal planarThree pairs separate as much as
possible but are unaffected by the lone pair of
electrons. Angles are 120 degrees Example BH3
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Trigonal bipyramidalFive pairs separate as
much as possible but are unaffected by a lone
pair of electrons Angles are 90 120 degrees
Example PCl5