Question

Why are London dispersion forces related to boiling point?

Answer 1

Simply because `"London"` or `"dispersion forces"` are intermolecular (or interatomic) bonds........

Explanation:

As you know, boiling points reflect intermolecular forces. Molecules with strong intermolecular forces tend to have higher boiling points. Thus water and ammonia have disproportionately high boiling points, which are what at normal pressure?

In the absence of other intermolecular forces, larger molecules tend to have higher melting and boiling points, as they have larger, and more polarizable electron clouds. And thus the boiling points of the inert gases INCREASE down the Group, as the atomic number increases, the electronic cloud becomes larger and more disperse, and dispersion forces increase proportionately.