Solve the following problem:
Q: A 100-L insulated tank contains N2 gas at 200 kPa and ambient temperature 25°C. The tank is connected by a valve to a supply line flowing CO2 at 1.2 MPa, 90°C. A mixture of 50% N2, 50% CO2 by mole should be obtained by opening the valve and allowing CO2 flow in to an appropriate pressure is reached and close the valve. What is the pressure? The tank eventually cools to ambient temperature. Find the net entropy change for the overall process.