Question

The gas that makes up about 12 percent of the earths atmosphere is ?

Answer 1

Answer:

You may be referring to the gas that makes up 21% of the earth's atmosphere, which is oxygen.

Explanation:

According to NASA, the gases in Earth's atmosphere include:

Nitrogen — 78 percent

Oxygen — 21 percent

Argon — 0.93 percent

Carbon dioxide — 0.04 percent

(Trace amounts of neon, helium, methane, krypton and hydrogen, as well as water vapor)