Multiple choice

Which gas is most abundant in the atmosphere?

  1. N2

  2. O2

  3. H2

  4. CO2
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nitrogen (N2) makes up approximately 78 percent of Earth's atmosphere, making it the most abundant gas. Oxygen (O2) follows at about 21 percent.

Keep practicing — related questions