Benzene (l) has a vapor pressure of 0.1269 bar at 298.15 K and an enthalpy of vaporization of 30.72 kJ mol-1. The CP,m of the vapor and liquid phases at that temperature are 82.4 and 136.0 J K-1 mol-1, respectively. Calculate the vapor pressure of C6H6(l) at 340.0 K assuming

When liquid is freezing the energy flows out the the liquid. As the kinetic energy decreases, they move more slowly. At the freezing point, some molecules move slowly enough for the attractions between molecules to have effect. Any energy removed from solid after phase change will mean decrease in kinetic energy or temperature.

The answer is when it’s freezing!.