Although they last mere milliseconds at any single frequency, their great
distances from Earth — and
large quantities of intervening plasma — delay their arrival at lower frequencies, spreading the signal
out over a second or more and yielding a distinctive downward - swooping «whistle» across the typical radio receiver band.
OTOH, if by this you mean that both gases will have equilibrium densities and partial pressures that more or less exponentially decay, with distinct exponential constants so that the static equilibrium mixture will not end up being perfectly homogeneous
over very
large vertical
distances, especially if one molecule is physically much
larger than and more massive than the other, I don't have a quarrel with that (and neither does Dalton), although I would want to work
out the numbers.