Question

1-kg of R-134a initially at 600 kPa and 25 °C undergoes a process during which the entropy is kept constant until the pressure drops to 100 kPa. Determine the final temperature of the R-134a and the final specific internal energy.

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A closed system containing R-134a initially at 280 kPa and 30 °C
undergoes a reversible isothermal process, after which its quality
is 0.40. (a) What is the specific heat and work transfer, q and w,
experienced by the system? (b) Sketch the process on a T-s diagram,
labeling the states and the isobars.

Problem Statement. A steel bottle with a volume of 0.1-m^3
contains R-134a at 20°C and 200-kPa. It is placed in a deep freezer
where it is cooled to -20°C. The freezer sits in a room with an
ambient temperature of 20°C and has an inside temperature of -20°C.
The internal energy of the R-134a before it is placed in the
freezer is … -kJ/kg
173.65
323.99
395.27
985.53
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Question 124 pts
The mass of the R-134a in...

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