What are the Properties of Refrigerant 134a in a Piston-Cylinder Device?

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The discussion focuses on determining the properties of refrigerant 134a in a piston-cylinder device, specifically the final pressure, change in volume, and change in enthalpy as the temperature increases from -10 to 15 degrees Celsius. The initial pressure is calculated to be 90.4 kPa, which is confirmed as correct. For the change in volume, the user is advised to utilize specific volume tables for refrigerant 134a at both initial and final states. The user expresses frustration over a lack of responses after two days, indicating a need for guidance on applying the tables correctly. Overall, the thread highlights the challenges in thermodynamic calculations involving refrigerants.
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A piston-cylinder device contains 0.85 kg of refrigerant 134a at -10 degrees celsius. The piston that is free to move has a mass of 12 kg and diameter of 25 cm. The local atmospheric pressure 88 kPa. Now, heat is transferred to refrigerant 134a until the temperature is 15 degrees celsius. Determine
(a)the final pressure
(b)the change in the volume of the cylinder and
(c)the change in enthalpy of the refrigerant 134a

I did part a and got it to be 90.4 kPa as P1 = P2, a value of which I am about 95% sure being correct.

As for part b, I deduce that I should use the tables in some method but I'm stumped with how to proceed. I tried to calculate the V of initial and final to get delta V but I am stuck at this equation

V = mv

So I figure i may have to use -10 degrees celsius and 90.4 kPa to get the specific volume at the initial state and 90.4 kPa and 15 degrees celsius to get specific volume at the final state.

Plz pt me in the right direction if you can.
 
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c'mon guys its been over two days an no help...oh man
 
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