Please see my question below:?

Question

Explain the trend in the normal boiling points of these liquids in terms of intermolecular forces.
CH4 normal boiling point: -161.5°C


CF4 normal boiling point: -28°C

CCl4 normal boiling point: +77°C

CBr4 normal boiling point: +190°C

Answer 1

As the total number of electrons in this series increases, the strength of the London dispersion forces also increases. As the dispersion force increases, the boiling points increase.