We have a heat engine working between to thermostats and filled with an ideal gas. It is based on a reversible thermodynamic cycle with two isotherm steps and two adiabatic steps. The minimum and maximum temperatures are $300C$ and $600C,$ the minimum and maximum volumes are $1l$ and $5l,$ the amount of gas is $n=1$mol. Calculate the efficiency of the cycle, and compare it to the Carnot cycle between the same thermostats. How would the efficiency change if we use a real gas instead of an ideal gas?

Efficiency of this cycle:

Compared to the Carnot cycle:

Comparison with an engine using real gas: