VSEPR Theory

Valence Shell Electron Pair Repulsion

• if there are electron pairs in the valence shell of an electron, they will repel.

• the pair of electrons will take up positions as far away from each other as possible causing a bend in the shape of the molecule

5 possible shapes:

linear

no repulsion, 2 bonding pairs, no lone pairs

bent

• repulsion, 2 bonding, pairs, 2 lone pairs

  

trigonal planar

• no repulsion, 3 bonding pairs, no lone pairs

pyramidal

• repulsion, 3 bonding pairs, one pairs

tetrahedral

• no repulsion, four bonding pairs, no lone pairs

polarity using vsepr theory:

• if there is repulsion, it’s polar

• when there is an equal sharing of e-, it is non-polar

• when the sharing is unequal, there is repulsion, therefore it is always polar when there is repulsion