A constant pressure piston-cylinder device of volume 2-m^3 contains 1.5kg of wat

Question

A constant pressure piston-cylinder device of volume 2-m^3 contains 1.5kg of water at a pressure of 200kPa.

(A). What is the specific volume, v, of the water? (ANS: v=1.33 m^3/kg)

(B). What is the temperature of the water? (ANS: T=305 degrees C)

(C). If the energy is removed until the volume is 1.0 m^3, what is the temperature? (ANS: T=120.2 degrees C)

(D). If energy continues to be removed until the temperature is 110 degrees C, what is the total internal energy, U, of the water in units of kJ? (ANS: u=691.9kJ)

These are the questions and answers, I'm interest in how to get those answers. Please be very specific and how you arrived at the answers, including the name of any table you used. Thanks.

Explanation / Answer

It won't let me upload my images.... I had to convert P =200kPa to 2bar in order to use my tables
A. v=V/m. So v=2.0m^3/1.5kg= 1.33m^3/kg
B. using the super heated water vapor tables and interpolating I found T with P=2bar and v=1.33m^3/kg. My T was 200'C. Interpolation= (y2-y1)/(x2-x1) = (y{need} - y1)/(x{given} - x1) Solve for y{need}
I see that this is not your answer. I do however feel that this could be because of a discrepancy between the Tables used or perhaps a math error in the interpolation.
C. Using the pressure driven water table and P=2bar I fond T =120.2 'C

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