(3) A piston-cylinder has been filled with liquid water (H2O) and is being heated on top of a burner. 78 kJ of heat are delivered to the piston cylinder while 10

kJ of heat are lost to the surroundings during the entire process (over 4t). As the liquid water is heated it undergoes a phase change and begins to expand. During this expansion, the liquid water will push the cylinder upwards in order to make room for itself, performing 6.5 kJ of work on the surroundings. Part A: Determine the AEsystem (neglect AKE, APE) during this energy transfer process. Part B: This system was designed to change a heat input into a mechanical work output and raise the piston. As a result, we can define its efficiency as n = Wout/Qin. Determine the efficiency of the process. W to push surroundings out of the way H₂O Qin Qloss Part C: If the walls of the system were well insulated (adiabatic), what is the efficiency? How come the efficiency is not 1 (i.e. where did some of the heat go during this process?).