Consider a liquid at 90 bar and 40 °C. What is the change in entropy of the substance as you change the conditions to 1 bar and 150 °C by expanding the liquid while heating?
Vapor pressure = 59.2 bar
heat of vaporization = 1.82 kJ/mol , both at 150 degree C
Heat capacity = 17.5 J/mol K
equation of pressure - PV/RT = 1 + (BP/RT)
2nd virial coeff, B = b - (a/T^2)
where a = 4.9*10^7 K^2cm^3/mol and b = 24cm^3/mol