What percentage of the atmosphere is oxygen?
1 Answer
Oct 18, 2017
21%
Explanation:
Dry atmosphere is 78% Nitrogen, 21% oxygen and 0.9% argon. The remaining 0.1% is mostly Carbon Dioxide, the rest is trace gases.
The amount of water vapor in the atmosphere is extremely variable, from near 0 to as high as 4%. This variable is why we normally just talk about dry air.