Sources of Oxides of Nitrogen
In our atmosphere and relating to air pollution, nitrogen oxides are most commonly referring Nitric Oxide(NO) and Nitrogen Dioxide(NO₂), collectively reffered to NOx.
Nitrogen Monoxide and Nitrogen Dioxide can be found naturally: during thunderstorms, around geothermal hot springs, and also in the soil. People also do introduce Nitrogen to the soil, via synthetic fertilizers.

 

People also cause the emission of Nitrous oxide when introducing Nitrogen to the soil, via synthetic fertilizers. 
It is also produced as a byproduct from industrial sources, such as thermal power generation plants, internal combustion engines vehicles burn fuel in, the production of Nitric acid, and the production of Adipic acid.



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Chemistry "O"Level TextBook 


 

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