At rigid vessel of 0.2 m3 is divided into two equal parts (call them A and B). The tank is insulated on the outside and the partition between the two sections is also an insulator. The partition can withstand a pressure differential across it of 400 kPa, before rupturing. Side A contains methane gas and B contains carbon dioxide, each initially at 1 MPa, 30 C. A valve on side B opens and CO2 flows out.
Assume that any CO2 remaining in B undergoes a reversible adiabatic expansion. The partition ruptures and at the same instant the valve is shut. Calculate the entropy change of the universe that occurs after the valve is closed. Assume ideal gas behavior with constant specific heats, cv meth= 27.3 kJ/(kmole-K), cv co2 = 28.9 kJ/(kmole-K).