Question

The relative strength of intermolecular forces as follows:

hydrogen bonding>dipole-dipole>London dispersion

Which of the following intermolecular force, when present in a substance, will typically result in the lowest vapor pressure?

Select the correct answer below:

dispersion forces

dipole-dipole

hydrogen bonding

There is no relationship between type of intermolecular force vapor pressure, so any of the above is equally likely.

Answer 1

Answer : Hydrogen bonding

Vapor pressure is the pressure exerted by molecules in vapor phase[gas phase] when
liquid is evaporated.
when more gas molecules are present higher will be its vapor pressure.

Stronger intermolecular force indicates molecules have more tendency to stay together
due to attraction.So they will remain in liquid state/evaporation will be less.Because In gaseous phase there is no intermolecular forces. Thus
vapor pressure of compounds having strong intermolecular force will be small.
Hydrogen bonding is the strongest intermolecular force. Hence vapor pressure

of compounds having hydrogen bonding will be the lowest