Air is a mixture of gases. It is not an element or a compound. The primary components of air are nitrogen (about 78%) and oxygen (about 21%). The remaining 1% consists of other gases like argon, carbon dioxide, and trace amounts of other elements and compounds.
An element is a substance that cannot be broken down into simpler substances by chemical means. A compound is a substance formed when two or more elements are chemically bonded together. In contrast, a mixture is a combination of two or more substances that are not chemically bonded and can be separated by physical means.
Since the gases in air are not chemically bonded and can be separated by physical processes like fractional distillation, air is classified as a mixture.