What are the primary elements that make up the earth's atmosphere?

Nitrogen - 78%

Oxygen - 21%

Argon - 0.09%

Carbondioxide - 0.04%

Trace elements (neon, krypton,..)

Explanation:

The atmosphere consists of various gases. Theses gases do exists in different amount and include gases such as Nitrogen, carbondioxide, Nitrogen, Methane, Argon, krypton, hydrogen, water vapor and so on. These gases are mainly seperated into 4 based on its percentage.

The most abundant gas by far is Nitrogen which makes up about 78% of the atmospheric gases, followed by oxygen which contains about 21% and Argon with about 0.09%, carbon dioxide with about 0.04% and Other elements which include krypton, Methane, water vapor etc making up the remaining percentage and all these gases which are only a very small percentage of the atmospheric gases are called trace gases.