Question

Why are the melting and boiling points of noble gases much lower as compared to those of other substances of comparable molecular masses?

Answer 1

1. Noble gases are monoatomic and have very stable closed-shell electronic configurations.
2. Their atoms are held together only by very weak van der Waals forces in the liquid or solid state.
3. These weak forces require only a small amount of heat to break, resulting in very low melting and boiling points.
4. The melting and boiling points increase down the group because atomic size increases, strengthening van der Waals forces.
5. Compared to other substances of similar molecular mass, noble gases have much lower melting and boiling points due to these weak intermolecular forces.