Molar Enthalpy of Fusion Definition

Ice melting into water droplet
Molar enthalpy of fusion is the energy absorbed to melt one mole of solid into a liquid.

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Molar enthalpy of fusion is the amount of energy needed to change one mole of a substance from the solid phase to the liquid phase at constant temperature and pressure. It is also known as the molar heat of fusion or latent heat of fusion. Molar enthalpy of fusion is expressed in units of kilojoules per mole (kJ/mol).

Finding Molar Enthalpy of Fusion

One method of finding molar enthalpy of fusion is experimentally using a calorimeter. The other method is to consult a table of the molar enthalpies of selected substances. A table usually includes the molar enthalpies of vaporization and fusion. Usually the pressure is 1 atm (101.325), unless otherwise stated.