Random ideal law question.

[September24]

1. I was just thinking. I know the answer to this question but I don't know... Why. For some reason.

If you have a closed right container with a certain volume of liquid. As the liquid vaporizes, what happens to pressure in the container. There would be more gases so gases would be bouncing around and hitting the walls. Therefore the pressure should increase? But can the ideal gas law explain this?

Pv=nrt
if pressure increases, what on the right side changes? I assume it would be moles. I'm just making sure. I know it's a silly question.

2. This is also random but has anyone faced any questions regarding density and the ideal has law? Like how does density change as temperature, pressure, and moles change. If so, how should the density relate to the ideal gas law. It's a really vague question so any help is appreciated. None of my books covered this I believe.

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[Sammy1024]

If pressure increases, moles or temperature can increase (r usually stays the same, since its a constant).

As liquid vaporizes, temperature within the container is increasing, which gives the molecules more energy to collide, increasing the pressure (if the volume of the container remains constant).

 

[DrknoSDN]

I assume it would be moles. I'm just making sure.

Moles increase. You could also ask if you have 1 gram of water vapor and add another gram of water vapor to it (regardless of how you do it, but in your example it's evaporation), what increases?
Pressure and Moles.

 

[camaryal]

For your second question, you can find out how density relates to the ideal gas law through the following equations:
1) density=mass/volume (density=m/V)
2) PV=nRT or P=[(mass/molecular weight)RT]/V
Now substitute #1 into #2. We have mass/volume in #2, so that just becomes density:
P=(density)RT/molecular weight
Density=P*MW/RT
This equation is now independent of the amount of material, so only P and T can change.