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lbenedi
Sep11-08, 11:37 PM
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.