Chemistry Computation of Liquid/Vapor Result during a Volume Expansion

AI Thread Summary
The discussion centers on finding methodologies to calculate the liquid-to-vapor phase change during volume expansion beyond Boyle's Law. The user, Bruce, seeks guidance on formulating equations to determine vapor production and liquid volume reduction as pressure decreases. Key parameters include the number of moles, density, and molar mass, which Bruce provides for water. Suggestions for references on phase change mechanics are shared, emphasizing the need for understanding vapor pressure and enthalpy data. The conversation highlights the complexity of accurately modeling the phase change process under varying conditions.
Bcavender
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Homework Statement
PROBLEM:

An expandable container, with a starting volume of 0.5 liter is filed completely with a liquid having a vapor pressure of 2.4 kPa.

The internal starting pressure is 1 atm and temperature of 20 degrees C.

The container expands to a new volume of 30 liters.

What are:

(1) The final volume of liquid at equilibrium?

(2) The internal pressure at equilibrium?

(3) The temperature of the gas?

(4) The temperature of the liquid?
Relevant Equations
I am searching for the appropriate methodology/equation(s) to step beyond Boyle's Law to account for the phase change and solve this problem.

All suggestions/guidance is greatly appreciated!
Bruce
I am searching for the appropriate methodology/equation(s) to step beyond Boyle's Law to account for the phase change and solve this problem.

All suggestions/guidance is greatly appreciated!
Bruce
 
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You have not fully constrained your inquiry; what other information do you need to furnish for us to answer your question?
 
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Bystander said:
You have not fully constrained your inquiry; what other information do you need to furnish for us to answer your question?

Good afternoon Bystander,

I am not sure what further constraints you speak of. My chemistry background is limited as I do mostly electrical/electronic work and I am exploring for a methodology for my super.

Boyles Law may come into play some way partially or not, but I lack the understanding of how to approach a formulation of the equation(s) for the vapor production and liquid volume reduction as the volume increases and pressure drops.

How can I further determine the parameters that are necessary to "fully constrain" the question?

Thanks!
Bruce
 
Bcavender said:
parameters that are necessary to "fully constrain" the question?
Number of moles, or equivalent information (density plus molecular weight plus total volume/mass) for starters; get you going?
 
Bystander said:
Number of moles, or equivalent information (density plus molecular weight plus total volume/mass) for starters; get you going?

Density = 0.99802 g/cm^3
Starting Volume = 500 cm^3 (all liquid)

Molar mass = 18.01528 g/mol
Total Mass = 499.01/18.01528 = 27.7 mol

Can you suggest a reference where I can find the methodology to understand the mechanics and computation of how much mass becomes vapor after expansion from 0.5L to 30L and other conditions?
 

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Bystander said:

OK, let's see if this is progress.

For a given amount of volume expansion, a new liquid/gas equilibrium point would be where the amount of vapor moles produced would allow the pressure in the gas volume to grow to equal the vapor pressure of the remaining liquid given compensation for by the phase change temperature drop in the gas molecules as well as the liquid volume reduction due to vaporization.

Would this statements be correct?Bruce
 
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You need any enthalpy/latent heat data for this ?
 
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