Comment by pfdietz
Gases in the atmosphere separate by molecular weight only at very high altitude, above the "homopause". This is from 80 to 120 km. Below that altitude, turbulence remixes gases faster than they can separate.
Gases in the atmosphere separate by molecular weight only at very high altitude, above the "homopause". This is from 80 to 120 km. Below that altitude, turbulence remixes gases faster than they can separate.