Why is air considered a mixture and not a compound?

 

Air is a mixture because:

• It is made of gases like nitrogen, oxygen, carbon dioxide, and others in varying amounts.

• These gases are not chemically combined but just physically mixed.

• The composition can change (e.g., in polluted cities, more carbon dioxide is present).

In a compound, the composition is always fixed (like H₂O always has 2 parts hydrogen and 1 part oxygen), but in air it is not.