Question

In which molecule is van der Waals force most likely to be important in determining the melting point and the boiling point?

• A. $ICl$
• B. $B{r}_2$
• C. $H_{2}S$
• D. $CO$

Answer 1

The correct option is B $B{r}_2$

Boiling point and melting point is determined by the strength of van der Waals forces in the case of non-polar molecules which inturn depends on the size of the molecule.

Since $B{r}_2$ is non-polar, the van der Waals forces will determine its melting and boiling point. Since the other given molecules are polar, dipole-dipole interactions will determine their melting and boiling point.