I should have posted this message before sharing what I know about
cloud chambers.
1) Consider a vessel filled with air. The bottom of that vessel is kept
at a constant temperature of -60 C while the top is kept at +20 C. At
time zero the vessel is sealed. What will the vertical distribution of
density become? What will the vertical distribution of pressure become?
2) An open dish with alcohol is placed near the top of the vessel
before it is sealed. The evaporation of alcohol will be taking place.
At the same time condensation of alcohol will be taking place at the
cold bottom "floor." What will the vertical distribution of density
become? What will the vertical distribution of pressure become?