Xenon has the highest boiling point.
Down a group in the periodic table, due to a higher number of electrons in the molecules, there is greater distortion and higher frequency and magnitude of the temporary dipoles. Thus, Van der Waal’s forces between the molecules are stronger, and the melting and boiling points are greater down the group.
Factors affecting the boiling point
- The relative strength of the four intermolecular forces is Ionic > Hydrogen bonding > dipole> Van der Waals dispersion forces.
- The influence of each of these attractive forces will depend on the functional groups present.
- Boiling points increase as the number of carbons is increased.
- Branching decreases the boiling point.
- For molecules with a given functional group, the boiling point increases with molecular weight.