Standard Enthalpy of Formation, \(\Delta H_{\rm f}^\circ \) Solved The standard enthalpy of vaporization (delta H Chegg.com thermodynamics $\Delta \bar{h}_{vap}$ and $\Delta \bar{s}_{vap}$ from vapor pressure vs. temperature data Chemistry Stack Exchange Solved Heat, q, is energy transferred between a system and Chegg.com 24 19. (a) Use Trouton's rule, Delta Hvap^circ approx (88 Heat of Vaporization from Vapor Pressure (Example)