Question

2 kg of steam initially at 2.00 MPa and 225?C expands in a piston-cylinder assembly until the final pressure is 0.10 MPa. During the process, the temperature of steam is kept constant by keeping it in a constant temperature atmosphere at 225?C. a. What is the maximum amount of work that can be produced? What is the entropy change of steam? What is the entropy change of the universe? b. Suppose that the actual work done is 80% of the maximum work. What is the entropy change of steam in this case? What is the entropy change of the universe?

Answer #1

Entropy From Steam Tables
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