Question

Differentiate between primary pollutants and secondary pollutants.

What is the difference between the Primary and Secondary pollutants?

Answer 1

	Primary pollutants		Secondary pollutants
1	They are emitted directly from the source.	1	They are not emitted directly from the source but are formed due to chemical reactions.
2	They are found in the atmosphere in the form in which they are emitted.	2	They are formed in the atmosphere by chemical reactions between primary pollutants and atmospheric constituents.
3	Ash, smoke, dust, radioactive compounds, oxides of sulphur, carbon, and nitrogen are primary pollutants.	3	SO3, O3, hydrogen cyanide, peroxyacetyl nitrate, ketones, etc., are secondary pollutants.