Problem 9.4:
An insulated cylinder is divided by a partition into two compartments.
Compartment A contains 0.2 mol of pure methane at 50 °C, 1 bar. Compartment B contains 0.8 mol of a methane-ethane mixture at 100 °C, 1 bar with ymethane = 0.5. The partition is removed and the system reaches equilibrium.
a) What is the composition of the final mixture?
b) What is the temperature and pressure at the end of the process?
c) Calculate the entropy generation.
d) What is the change in the total Gibbs energy of the system?
e) How much work is needed to separate the final mixture into A and B at the conditions before mixing? Assume that the temperature of the surroundings is 20 °C.
f) Which of the above answer would change (and by how much), if both compartments contained methane? All other conditions are the same.
Additional data: The ideal-gas CP 's of the pure components are: ethane: 10.3 R; methane: 6.2 R; where R is the ideal-gas constant.