One liter of saturated liquid water is contained in a piston-cylinder assembly. Initially,the water pressure is 2bar. 1000 kJ of heat are transferred to the water, after which the pressure of the water reaches again 2bar. Assume the process is reversible and that the boundary temperature is kept at 100 ºC all the time. Calculate the quality of the water when the process has been completed and the work done by the piston to the surroundings.
One liter of air is at 27ºC and its pressure is 10 bar. 500 J of heat are transferred to theair allowing the pressure of the system to vary until it returns again to 10 bar. Assume the process is reversible. During the process the boundary temperature is kept at 80 ºC.
Determine the work done by the piston to the surroundings. For the air consider
cp=1kJ/kgK and mean molecular weight 28.96kg/kmol.