Latent heat

Latent heat (kJ/mol) is the change of total heat energy involved in phase changes. Three types of latent heat are involved: latent heat of fusion, latent heat of evaporation, and latent heat of sublimation.

Latent heat of fusion

Latent heat of fusion or enthalpy of fusion (Δ_H__fus) is the amount of heat required to change one mole of a substance from the solid state to the liquid state.

Latent heat of evaporation

Latent heat of evaporation or enthalpy of evaporation (Δ_H__vap) is the amount of heat required to change one mole of a substance from the liquid state to the gas state.

The enthalpy of sublimation can be estimated as the sum of its enthalpy of fusion and vaporization.