The three main types of intermolecular forces, ranked from weakest to strongest, are:
- London Dispersion Forces: These are the weakest intermolecular forces and occur between all molecules, whether polar or nonpolar. They are caused by temporary dipoles that arise due to the movement of electrons.
- Dipole-Dipole Interactions: These forces are stronger than London dispersion forces and occur between polar molecules. They result from the attraction between the positive end of one polar molecule and the negative end of another.
- Hydrogen Bonds: These are the strongest intermolecular forces and occur when hydrogen is bonded to highly electronegative atoms like nitrogen, oxygen, or fluorine. The hydrogen atom in one molecule is attracted to the lone pair of electrons on the electronegative atom in another molecule.
Understanding these forces helps explain various physical properties of substances, such as boiling points, melting points, and solubility.