1. The problem statement, all variables and given/known data Ammonia at 10C with a mass of 10kg is in a piston/cylinder assembly with an initial volume of 1 m^3. The piston initially resting on the stops has a mass such that a pressure of 900 kPa will float it. Now the ammonia is slowly heated to 50C. Find the final pressure and volume. 2. Relevant equations Vo(specific volume)=volume/mass Vf of saturated ammonia @ 10C = .0016 m^3/kg Vf of sat. ammonia @ 50C= .00177 m^3/kg Vg of sat. ammonia @ 10C = .20541 m^3/kg Vg of sat. ammonia @ 50C = .06335 m^3/kg 3. The attempt at a solution My attempt was assuming the final pressure to be 900kPa and solve for V that way, but there is no way for me to check if that is correct.