I highly doubt this will be answered.?

Saturated CO2 vapor expands (in an isentropic/adiabatic expansion) from 60F (I'm using English units) and 747.4 psi to 40F and 567.3 psi. The enthalpy decreases by 4.9 btu/lb (from 132.2 to 127.3), resulting in 62.5% vapor and 37.5% liquid. Is the decrease caused by the attraction of the molecules resisting the expansion, and is this attraction of the molecules an electromagnetic force? Conversely, if the gas was compressed from the lower pressure and temperature to the higher, would there not be an increase in enthalpy in excess of the enthalpy of the lower pressure gas (which is 136.8btu/lb), caused by the attraction of the molecules isting the compression, and would this increase in enthalpy not take the form of a much higher temperature than 60F? Finally, can the attraction of the molecules be considered to be a form of potential energy which is converted into kinetic when the gas expands?