Intro Thermodynamics Question using Steam Tables

AI Thread Summary
The discussion revolves around determining the pressure reading in a rigid container filled with water as it is heated to the point of becoming saturated vapor. Initially, the container holds 2 gallons of water at a pressure of 10.2 psig, with the absolute pressure calculated to be 25 psia. The participant understands the use of steam tables and T-v diagrams but is uncertain about how to relate the saturated vapor condition to the pressure after heating. They identify that, with a constant volume and all liquid turning to vapor, the specific volume remains the same, leading to the need to consult steam tables for the corresponding pressure and temperature. Clarification on these calculations and the relationship between the conditions is sought for a better understanding.
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Homework Statement



A transparent rigid container is filled with 2 gallons of water. Initially the pressure is
measured to be 10.2 psig, using a gage attached to the container. The local atmospheric pressure is 14.8 psia. It is observed that the liquid water in the container occupies two percent of the container volume. The water in the container is heated. Determine the reading on the pressure gage in psig when all the liquid has just turned to vapor (all saturated vapor). Show this process on a sketch of a T-v diagram.

Homework Equations



Equatin for quality: v = vf + x(fg)

The Attempt at a Solution



I understand the concept of steam tables. And I understand exactly what this looks like on a T-v diagram. I guess I am getting too bogged down in the information given to not know what to consult the steam tables for.

I understand that the absolute pressure in the container before being heated is 25 psia, so I can get a saturated temperature reading from that, and a specific volume based on the fact the 98% of the water is steam (see above equation). But I'm not sure how to related that to the container once it's been heated. The volume stays constant and I'm left with saturated vapor, but what does that mean for the pressure?

Any help is appreciated and I'll be happy to clear up any blurry areas of my question.
 
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Condition 1: P1=25psia. T1:240 F, V1=.8 ft^3/Lb, X=4.8%

Condition 2: V2=.8 ft^3/lb, x=100% because you are saturated vapor, Vg=V2=.8 ft^3/lb

look on steam tables at Vg= .8 ft^3/lb to find P2 and T2
 
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