At room temperature (25°C or 77°F), the enthalpy of water is approximately 105.4 kilojoules per mole (kJ/mol). Enthalpy is a thermodynamic property that represents the total heat content of a substance, including both its internal energy and the work done by its expansion. In the case of water at room temperature, this value of enthalpy corresponds to the energy required to raise the temperature of one mole of liquid water from its freezing point (0°C or 32°F) to 25°C while maintaining constant pressure.