Calculation of Enthalpy of Vaporization at a Given Temperature 24 19. (a) Use Trouton's rule, Delta Hvap^circ approx (88 5 gram Delta 8 Disposable THC HHC Vape Pen with Preheat 4asvapes Vaping Products Standard enthalpy of vapourisation `Delta_("vap")H^( )` for water at `100^@C` is `40.66 kJ mol^( 1)`. The internal energy of vapourisation of water at `100^@C` (in kJ `mol^( 1)`) is (Assume water vapour to behave like Solved The standard enthalpy of vaporization (delta H Chegg.com