The maximum work that can be obtained from the expansion of an ideal gas at constant temperature and pressure is achieved during a reversible isothermal expansion. In an irreversible expansion, the work obtained is always less than that of a reversible process.For a reversible isothermal expansion of an ideal gas, the work done W can be calculated using the following formula:W = -nRT * ln Vf / Vi where:- n is the number of moles of the gas- R is the ideal gas constant 8.314 J/molK - T is the constant temperature in Kelvin- Vf is the final volume of the gas- Vi is the initial volume of the gas- ln is the natural logarithmSince the irreversible expansion will yield less work than the reversible process, the maximum work that can be obtained from the irreversible expansion of an ideal gas at constant temperature and pressure will be less than the value calculated using the above formula.