An uninsulated cylinder fitted with a piston contains air at 500 kPa, 200?C, at which point the volume is 10 L. The external force on the piston is now varied in such a manner that the air expands to 150 kPa, 25 L volume. It is claimed that in this process, the air produces 70% of the work that would have resulted from a reversible adiabatic expansion from the same initial pressure and temperature to the same final pressure. Room temperature is 20?C.
a. What is the amount of work claimed?
b. Is this claim possible?