Consider fi lling a “type A” gas cylinder with water from a high-pressure supply line as shown on next page. Before fi lling, the cylinder is empty (vacuum). The valve is then opened, exposing the tank to a 3-MPa line at 773 K until the pressure of the cylinder reaches 3 MPa. The valve is then closed. The volume of a “type A” cylinder is 50 L.

(a) What is the change in entropy of the universe immediately after the valve is closed?

(b) If the cylinder then sits in storage at 293 K for a long time, what is the entropy change of the universe?