Problem 6.5: Liquid propane boils in a constant pressure boiler to produce propane vapor at 30 bar and 245 °C. At the inlet of the boiler the propane is saturated liquid.
a) Draw a PV graph and show this process. Show all the relevant temperatures and pressures as well as the critical isotherm and the critical pressure.
b) Calculate the entropy change of propane between the inlet and outlet of the boiler. Explain your calculations and procedure clearly.
Additional data
1. The saturation temperature at 30 bar is 78 °C.
2. The heat of vaporization at 78 °C is 8780 J/mol.
3. The ideal-gas CP of propane vapor is 112 J/mol K.