AP BIOLOGY

Detailed explanation-1: -The most abundant gas in the atmosphere is nitrogen, second oxygen . Argon, an inert gas, is the third most abundant gas in the atmosphere.

Detailed explanation-2: -Earth’s atmosphere is composed of about 78 percent nitrogen, 21 percent oxygen, 0.9 percent argon, and 0.1 percent other gases.

Detailed explanation-3: -The most abundant naturally occurring gas is nitrogen (N2), which makes up about 78% of air. Oxygen (O2) is the second most abundant gas at about 21%. The inert gas argon (Ar) is the third most abundant gas at 0.93%.

Detailed explanation-4: -Oxygen is a major component of the solid earth, along with Si and elements such as Mg, Ca and Na. Nitrogen is not stable as a part of a crystal lattice, so it is not incorporated into the solid Earth. This is one reason why nitrogen is so enriched in the atmosphere relative to oxygen.

Detailed explanation-5: -The composition of Nitrogen in the air is 78 % which is the highest while Oxygen is present at 21 % and the percentage of Argon is   1 % while the other gases are in the trace amounts.