Delta Vap H Latent Heat of Vaporization Delta Hvap of Water calculated by corresponding states correlation Use Hess's law to prove that Delta subH = Delta vapH + Delta fusH. Homework.Study.com Delta_{vap}H^ for water is +40.49 kJ moi^ 1 at 1 bar and 100C . Change in internal energy for this vaporization under same condition is Sarthaks eConnect Largest Online Education Community Calculated and Experimental Enthalpies vap H and vap H exp of Download Table Vapor Pressure