Answer:
The enthalpy of vaporization (symbol Hvap), also known as the (latent) heat of vaporization or heat of evaporation, is the amount of energy (enthalpy) required to convert a quantity of a liquid substance into a gas. The enthalpy of vaporization depends on the pressure at which the transformation occurs.
The enthalpy of vaporization is frequently used to describe a substance’s normal boiling temperature.