Do you know what Gas makes up most of the earth’s atmosphere?

On this page, we will discuss what Gas makes up most of the earth’s atmosphere. The atmosphere of Earth, commonly known as air, is the layer of gases retained by Earth’s gravity that surrounds the planet and forms its planetary atmosphere.

The most abundantly present gas in the atmosphere by far is nitrogen, which accounts for about 78% of the mass of dry air. While the second most abundant gas in the atmosphere is Oxygen, present at levels of 20 to 21%. 

List of available gases in the atmosphere and their percentages

Gas Name	Chemical Formula	Percent Volume
Nitrogen	N2	78.08%
Oxygen	O2	20.95%
*Water	H2O	0 to 4%
Argon	Ar	0.93%
*Carbon Dioxide	CO2	0.0360%
Neon	Ne	0.0018%
Helium	He	0.0005%
*Methane	CH4	0.00017%
Hydrogen	H2	0.00005%
*Nitrous Oxide	N2O	0.00003%
*Ozone	O3	0.000004%

Sources

https://www.thoughtco.com/most-abundant-gas-in-the-earths-atmosphere-604006

https://kids.frontiersin.org/articles/10.3389/frym.2019.00041

http://tornado.sfsu.edu/geosciences/classes/m201/Atmosphere/AtmosphericComposition.html