Two moles of a monatomic ideal gas are warmed from 300 K to 400 K at constant pressure (R = 8.31 J/mol K). The work done by the gas is about:

The Carnot cycle alternates two isothermal steps (heat absorbed at T_H, released at T_C) with two adiabatic steps (no heat exchange); the enclosed loop area equals the net work output, and η = 1−T_C/T_H is the maximum possible efficiency between those two temperatures.