A car air-conditioning unit has a 0.5-kg aluminum storage cylinder that is sealed with a valve and

Question:

A car air-conditioning unit has a 0.5-kg aluminum storage cylinder that is sealed with a valve and 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?