How do Van der Waals forces affect the boiling point?

The boiling point increases with the strength of the Van der Waals forces.

If intermolecular forces hadn't been present, all molecules would have been gases. Intermolecular forces act as forces between molecules, causing them to become attracted to one another and transform into liquids or solids. This means that all simple molecules only need to be boiled or melted.

Therefore, the higher the boiling point, the more energy will be needed to overcome the intermolecular forces and transition from the liquid to the gaseous state.

Larger molecules will have higher boiling points because the strength of Van der Waals forces is primarily dependent on the total number of electrons in the molecule. For isoelectonic molecules, or isomers with the same number of electrons, the strength of the forces is determined by the area of surface contact; the more branched the isomer, the less closely it can pack, and therefore the weaker the Van der Waals forces.

Van der Waals forces affect the boiling point by increasing the attraction between molecules, which requires more energy to overcome, resulting in a higher boiling point.