Chemistry-TGhermodynamics Piston Cylinder Device question

AI Thread Summary
The discussion revolves around a thermodynamics problem involving a piston-cylinder device containing R-134A. The initial state includes 0.02m^3 of R-134A at 50°C, which changes as 20kg of R-134A enters at 800kPa and 80°C, leading to a final state of 1MPa, 100°C, and 0.6m^3. Participants express confusion about determining the quality of R-134A in the initial state due to the changing volume throughout the process. The conversation highlights the challenge of applying thermodynamic principles in dynamic systems where volume is not constant. Clarification on how to approach the quality calculation and the overall work and heat transfer is sought.
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Homework Statement



A piston cylinder device with a spring attached initially contains 0.02m^3 of R-134A at 50C. A valve connected to the cylinder is opened and 20kg of R-134A enters the device from a supply line at 800kPa and 80C. The spring is compressed and the piston moves up. The process stops when the pressure inside the cylinder reaches 1MPa, at a temperature of 100C and a volume of 0.6m^3.

a) The quality (x) of the R-134A in state 1?
b) Work done in this process (kJ)?
c) Amount of heat transferred to/from device (kJ)?


Homework Equations





The Attempt at a Solution



Im stuck at the quality aspect of the question. In most piston cylinder devices the volume is constant at least for a little but I think the volume is constantly changing throughout the problem. So I don't know how to get the quality with the information given.

Any help would be appreciated!
 
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I'm still thinking about "state 1"...

Quality? Perhaps that should be quantity?
 
No, it shouldnt.
 
glad it's your problem and not mine!
 
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