Question

Why is `n-C_10 H_22` boiling point higher than `Br_2` boiling point?

`Br_2` has bigger relative mass than `n-C_10 H_22` , and both are linear molecules. However, it has lower boiling point than `n-C_10 H_22` .

What is the cause of such situation?

Answer 1

Decane has a very slight dipole, whereas bromine has no dipole. Carbon and hydrogen have approximately a `0.35` difference in electronegativity.

This is a demonstration of how negligible dispersion forces are when there are also dipole-dipole interactions.

There may be other reasons, which I'm open to hearing!