Ammonia in a piston/cylinder arrangement is at 80°C, 700 kPa. It is now cooled at constant pressure to saturated vapour (state 2) at which point the piston is locked with a pin. The cooling continues to −10°C (state 3). Find the work.

Ammonia in a piston/cylinder arrangement is at 80°C, 700 kPa. It is

1.	Ammonia in a piston/cylinder arrangement is at 80°C, 700 kPa. It is now cooled at constant pressure to saturated vapour (state 2) at which point the piston is locked with a pin. The cooling continues to −10°C (state 3). Find the work.
A.	-28.64 kJ/kg
B.	-38.64 kJ/kg
C.	-48.64 kJ/kg
D.	-58.64 kJ/kg
Answer» C. -48.64 kJ/kg

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Ammonia in a piston/cylinder arrangement is at 80°C, 700 kPa. It is now cooled at constant pressure to saturated vapour (state 2) at which point the piston is locked with a pin. The cooling continues to −10°C (state 3). Find the work.

Ammonia in a piston/cylinder arrangement is at 80°C, 700 kPa. It is now cooled at constant pressure to saturated vapour (state 2) at which point the piston is locked with a pin. The cooling continues to −10°C (state 3). Find the work.

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