Air is a mixture, not a single chemical compound. It's primarily composed of:

* Nitrogen (N2) - about 78%

* Oxygen (O2) - about 21%

* Argon (Ar) - about 0.9%

There are also trace amounts of other gases like:

* Carbon dioxide (CO2)

* Neon (Ne)

* Helium (He)

* Methane (CH4)

* Krypton (Kr)

* Hydrogen (H2)

* Xenon (Xe)

* Ozone (O3)

The proportions of these gases can vary slightly depending on location, altitude, and other factors.