State 1	State 2	State 3	State 4
T (K)
P (bar)

	U (J/mol)	Q (J/mol)	W (J/mol)
1 -> 2
2 -> 3
3 -> 4
4 -> 1
Total

An ideal gas (CPig=40J/mol/K) is used to produce refrigeration in a closed system through a series of reversible steps. The gas is heated under constant volume from T1=300K,P1=1 bar, to T2=1500 K; then cooled under constant pressure to unknown temperature T3; this is followed by adiabatic expansion to T4=240K,P4=1 bar; and finally the gas is returned to its initial state by constant pressure process. Perform the energy balances and summarize your results in the table below (you must show your work to receive credit)