1. INTERMOLECULAR FORCES

2. Intermolecular Forces
Forces of attraction and repulsion between molecules.
They are weak – if we say that a covalent bond has a strength of 100 then intermolecular forces would range from to 15.

3. Dipole-Dipole
A relatively strong force of attraction between two polar molecules. † Can also have ion-dipole forces between ions and a polar molecule

4. Hydrogen Bonding Is an exceptionally strong dipole-dipole force
One of the three most electronegative elements, F, O or N must be covalently bonded to a hydrogen (such as HF, H2O, NH3 , CH3OH and CH3NH2).

5. London Forces The only attractive force nonpolar molecules.
… Basically the electrons in one atom are slightly attracted to the nuclei (positive core) of another atom.
… The greater the number of electrons the stronger the L.F.