1. A heavily insulated cylinder/piston contains ammonia at 1200 kPa, 60?C. The piston is moved, expanding the ammonia in a reversible process until the temperature is -20?C. During the process, 200 kJ of work is given out by the ammonia. What was the initial volume of the cylinder?

2. Water at 1000 kPa, 250?C is brought to saturated vapor in a piston/cylinder with an isothermal process. Find the specific work and heat transfer. Estimate the specific work from the area in the P-v diagram and compare it to the correct value.