A frictionless piston–cylinder device contains saturated liquid water at 40-psia pressure. Now 600 Btu of heat is transferred to water from a source at 1000°F, and part of the liquid vaporizes at constant pressure. Determine the total entropy generated during this process, in Btu/R.

5 kg block of steel initially at 160°C is dropped into an insulated tank that contains 12 L of water at 20°C. Determine (a) the final equilibrium temperature, (b) the specific entropy generated in this process.

An insulated piston-cylinder device contains 0.5L of saturated liquid water at a constant pressure of 100 kPa. An electric resistance heater inside the cylinder is now turned on, and 1178.36 kJ of electrical work is transferred to the steam. Determine (a) the entropy change of the water during this process; (b) the entropy generation during this process? 1178.36 kJ M H₂O 100 kPa Sat. liquid

A piston–cylinder device initially contains 15 ft3 of helium gas at 25 psia and 70°F. Helium is now compressed in a polytropic process (PVn = constant) to 70 psia and 300°F. Determine the entropy change of helium.