A constant-volume tank contains 5 kg of air at 100 kPa and 327°C. The air is cooled to the surroundings temperature of 27°C. Assume constant specific heats at 300 K.
(a) Determine the entropy change of the air in the tank during the process, in kJ/K,
(b) Determine the net entropy change of the universe due to this process, in kJ/K, and
(c) Sketch the processes for the air in the tank and the surroundings on a single T-s diagram. Be sure to label the initial and final states for both processes.