Question

Place the following liquids in ascending order (from lowest to highest) of viscosity, surface tension and vapor pressure.

methanol (bp = 64.7oC) CCl4 (bp = 76.72oC) C4H6Br4 (bp = 310oC)

Surface tension

Vapor pressure

Methanol is CH3OH

Answer 1

Methanol has inter molecular hydrogen bonds among its molecules.

C4H6Br4 has dipole dipole interactions among its molecules.

CCl4 has only weak london forces among its molecules.

So,

The increasing order of strength of intermolecular forces is,

CCl4 < C4H6Br4 < methanol

It is known that strength of inter molecular forces is inversely proportional to viscosity, surface tension and vapour pressure.

So the increasing order of viscosity , vapour pressureand surface tension is

Methanol < C4H6Br4 < CCl4