Question

What are the components of clean air?

Answer 1

In clean air there are 5 elements present.
Argon
Carbon Dioxide
Nitrogen
Oxygen
and Hydrogen
Hope this helps! :)

Answer 2

Using information I've learned doing GCSE core science, the air should contain:

78% Nitrogen (N2)
21% Oxygen (02)
0.035% Carbon Dioxide (CO2)
Fluctuating proportions of noble gases (such as argon) and water vapour

There are also trace amounts of many other gases.