Composition of atmospheric air and mean thermal speed

02 Jul 2021 - tsp
Last update 02 Jul 2021
Reading time 1 min

Gas type	Partial pressure (mbar)	Mean speed ($\frac{m}{s}$)	Mean molecule mass ($\frac{kg}{mol}$) at 20 Celsius
Nitrogen $N_2$	$791$	471	28
Oxygen $O_2$	$212$	440	29
Argon $Ar$	$9.46$	394	40
Water vapor ($H_2O$)	$\leq 23$	587	18
Carbon dioxide ($CO_2$)	$0.32$	375	44
Neon ($Ne$)	$1.8 * 10^{-2}$	557	20
Helium ($He$)	$5.3 * 10^{-3}$	1245	4
Krypton ($Kr$)	$1.1 * 10^{-3}$	272	84
Hydrogen ($H_2$)	$5.1 * 10^{-4}$	1761	2
Xenon ($Xe$)	$8.7 * 10^{-5}$	217	131
Ozone ($O_3$)	$2.0 * 10^{-5}$	360	48

This article is tagged: Atmosphere, Partial pressure, Thermal speed, Vacuum

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