A rigid, well-insulated tank contains a two-phase mixture of ammonia with 0.0025 ft3 of saturated liquid and 1.5 ft³ of saturated vapor, initially at p1 = 50 lbf/in². A paddle wheel stirs the mixture until only saturated vapor at higher pressure, p2, remains in the tank. Kinetic and potential energy effects are negligible. Determine the pressure p2, in lb/in², and the amount of energy transfer by work, in Btu.

A rigid, well-insulated tank contains a two-phase mixture of ammonia with 0.0025 ft3 of saturated liquid and 1.5 ft³ of saturated vapor, initially at p1 = 50 lbf/in². A paddle wheel stirs the mixture until only saturated vapor at higher pressure, p2, remains in the tank. Kinetic and potential energy effects are negligible. Determine the pressure p2, in lb/in², and the amount of energy transfer by work, in Btu.