phase changes.svg 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 How to calculate Delta S? Problems, Formulas, Units 5.4: Vapor Pressure Chemistry LibreTexts 24 19. (a) Use Trouton's rule, Delta Hvap^circ approx (88 Delta Vap H Latent Heat of Vaporization Delta Hvap of Water calculated by corresponding states correlation