Valence Shell Electron Pair Repulsion

  • Valence Shell Electron Pair Repulsion – allows us to predict the shape of molecules to better learn their properties (they are 3-D versus 2-D Lewis structures)
  • Molecules will assume arrangements that minimize the repulsion between the electron pairs around the central atom. 

VSEPR Models: Two bonded pair

VSEPR Models: Three bonded pairs of electron

VSEPR: Four bonded pairs of electron

VSEPR: Five and Six bonded pairs of electron

Polarity – based on the shape of the molecule

    • In a polar molecule, there is a net unequal sharing of the electrons.
    • If two dipoles are at angles they will NOT cancel out.
    • In a non-polar molecule, there is a net equal sharing of electrons.
    • If two dipoles are in opposite directions they will cancel each other.
    • This can be determined by looking at electronegativity and shape.