6. A piston-cylinder contains 2 lb of water, initially at 300°F . The water undergoes two processes: (20 points) Constant volume heating followed by a constant pressure process. At the end of constant lbvolume process, the pressure is 100 , and the water is a two -phase, liquid-vapor mixture in?with quality of 80%. At the end of the constant pressure process, the temperature is 400°F . Neglect Kinetic and potential energy effects. a) Sketch T – v and P – v diagrams showing the key states and the processes. b) Determine the work and heat transfer for each of the two processes, all in Btu.

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