CO2 makes up approximately 0.03% of Earth's atmosphere
The atmosphere is composed of approximatly 79% Nitrogen - 20% Oxygen - 1% Argon and 'other gasses'
i think 78 of hydrogen and about 20 percent of oxygen and other gases make up the other 2 percentage
With very few exceptions (you can make argon fluorides, but you have to work at it), the noble gases are nonreactive--they won't form compounds.
Any gas or group of gases can make a thin atmosphere.
Atmosphere.
There is no air in space. If you mean what is the atmosphere in the Space Station, it is essentially an ordinary Earth air mixture of nitrogen and oxygen.
Hydrogen and helium
The gases that make up Uranus' atmosphere is mainly hydrogen, helium, and methane.
Nitrogen and oxygen.
there are five noble gasses. They are noble because they cannot combine with anything. Nitrogen is noble because nitrates make awesome explosives Boom no go noble gas
Aside from Oxygen and Nitrogen, which make up roughly 99% of the Earth's atmosphere, the atmosphere is comprised of approximately 0.93% argon, and 0.038% carbon dioxide. The remaining 0.032% is a mixture of other gasses in relatively minuscule amounts.
Nitrogen and oxygen make up the largest percentage of the atmosphere.