Question

Twenty five pounds of propane are held in a sealed container at 350 psia. The volume of the container is 3 cu ft. calculate the weights and volumes of the two phases in the container.

Answer 1

25 pounds of propane will be the equivalent of 14.1 cubic feet of liquid propane. I'm not sure you can get it into a 3 cubic foot container.

If the propane is all vapor at 350 psia, the specific volume is about .30 cubic foot per pound. This means 25 pounds of propane would occupy about 7.5 cubic feet

You will need another fact to set the amount of liquid or vapor since at 350 psia, propane can be a liquid up to about 150 degs F. From that point it can be a mixture of liquid and vapor or all vapor. You should look for a Mollier diagram for propane and you can see what I am talking about.