1. One pound mass of water in a piston-cylinder assembly, initially a saturated liquid at 1 atm, undergoes a constant- pressure, internally reversible expansion to x 5 90%. Determine the work and heat transfer, each in Btu. Sketch the process on p-y and T-s coordinates. Associate the work and heat transfer with areas on these diagrams.
2. A gas within a piston-cylinder assembly undergoes an isothermal process at 400 K during which the change in entropy is 20.3 kJ/K. Assuming the ideal gas model for the gas and negligible kinetic and potential energy effects, evaluate the work, in kJ.
3. Water within a piston-cylinder assembly, initially at 10 lbf/in.2, 5008F, undergoes an internally reversible process to 80 lbf/in.2, 8008F, during which the temperature varies linearly with specific entropy. For the water, determine the work and heat transfer, each in Btu/lb. Neglect kinetic and potential energy effects.