Sugar in coke doesn't sink to the bottom, indeed, but if you put a sugar cube in water, it first sinks to the bottom, and then (slowly) dissolves.
Likewise, if you release helium in air, it goes up first, and then (quickly) dissolves in the air.
Disperses would be a better word than dissolves.
Diffuse would be a better word than disperses.
Re:iPhones are allergic to helium
by pankajdoharey on Wednesday October 31, 2018 @01:53PM
(#18347839)
Ahh true i didnt consider that. But the gas mixing would happen only at contact level, something like the meniscus between two fluids. i doubt they would homogenously mix unless the molecules have an affinity for each other, in heliums case it is an ideal gas.
Our atmosphere does not contain mostly O2 and N2 in the middle, with a layer of CO2, Ar, etcetera near the surface. The sugar in a bottle of coke does not spontaneously sink to the bottom.