Pressure increase closed container

[marantinj]

I was hoping someone can help me out with calculating the amount of pressure generated for a certain evaporation. I have a certain compound which is at liquid state below minus fifty degrees celcius (-50C).

It is then warmed up to room temperature 30C (completely closed system). The amount of liquid initially collected in the container is 1000g (31 mol). The container volume is 10L. If the critical temperature is below room temperature, then at room temperature all the liquid would have turned to dry gas. What is the pressure at this point? Since the mols does not change, is the PV=nRT equation valid?

 

[zdas04]

mariantnj,
You are new here and probably don't realize how annoyed people get with "a certain compound" and "certain evaporation" problem statements. Different compounds act differently and we mostly don't take well to trying to give generic answers to specific questions. To add to that the only place that anyone ever sees a container that is exactly 1,000g is in school work. School work is not allowed and this sure does look like school work.

David

 

[bchoate]

marantinj
I agree with zdas04's post that your post is suspicious. The liquid occupies about 10% of the container volume. If the container is filled with air at ambient conditions prior to adding the cold liquid, the number of moles of air is insignificant. There are several unknowns and a generalized solution can be attempted. Assuming that all the liquid vaporizes at 30 C, use the PV = nRT equation to calculate the pressure in psi (keep consistent units). An estimate of the pressure is 1100 psi. If the vapor pressure of the liquid is less than 1100 psi, then some of the liquid will not vaporize and both liquid and vapor will be in the container. The pressure will then be at the vapor pressure at 30 C.