1. A car air-conditioning unit has a 0.5-kg aluminum storage cylinder that is sealed with a valve. It contains 2 L of refrigerant R-134a at 500 kPa, and both are at room temperature, 20?C. It is now installed in a car sitting outside, where the whole system cools down to ambient temperature at -10?C. What is the irreversibility of this process?
2. R-134a is flowed into an insulated 0.2-m3 initially empty container from a line at 500 kPa, saturated vapor until the flow stops by itself. Find the final mass and temperature in the container and the total irreversibility in the process.