Heat of fusion: Meaning (information, definition, explanation, facts)

Heat of fusion is the heat absorbed by a unit mass of a solid chemical element at its melting point in order to convert the solid into a liquid at the same temperature. The heat of fusion is equal to the heat of solidification.

The energy that goes into melting a solid is used to dissociate the intermolecular bonds holding its molecules in place rather than to increasing the average thermal velocity of the molecules.