|MadSci Network: Chemistry|
Thank you for this interesting question.
The pressure and density of the gas in each cylinder will be a direct function of the molecular weight of each.
Xenon, with molecular weight of
131 grams/mole, has a density of 5.89grams/liter at standard temperature and
Helium on the other hand has molecular weight of only 4.9 grams/mole. At 0.179 grams/liter, it is more than 30 times lighter than Xenon.
By calculating the volume of the cylinder, you can derive the total weight of the gas it contains. The pressure at the bottom will simply be the total weights of each gas divided by the surface area of each cylinder's bottom.
E Lawrence MD
Try the links in the MadSci Library for more information on Chemistry.