Geothermal Thesaurus

Heat of vaporization

The Heat (or Enthalpy) of Vaporization is the quantity of heat that must be absorbed if a certain quantity of liquid is vaporized at a constant temperature. In a solution with both a vaporized and liquidized states, the kinetic energy of the vapor is higher than the kinetic energy of the liquid. Temperature follows kinetic energy, showing a lower temperature in the remaining liquid.

http://chemwiki.ucdavis.edu/Physical_Chemistry/Thermodynamics/State_Functions/Enthalpy/Enthalpy_Of_Vaporization

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