Standard Enthalpy of Formation, \(\Delta H_{\rm f}^\circ \) For water vap H = 41 kJ mol^1 at 373 K and 1 bar pressure. Assuming that water vapour Sarthaks eConnect Largest Online Education Community Law of Equipartition of Energy Energy is equally distributed among all degrees of freedom Each degree contributes kT per molecule Translational, rotational, DeltaH` (vap) for water is `40.7 kJ mol^( 1)`. The entropy of vapourisation of water is Vapor Pressure Latent Heat of Vaporization Delta Hvap of Water calculated by corresponding states correlation in a one cell excel formula Chem Eng Musings