What three pollutants react in the presence of sunlight to produce ozone?

1. Nitrogen oxides e.g Nitrogendioxide (NO2)

2. Carbon monooxide (CO)

3. Volatile organic compounds e.g hydrocarbons

Explanation:

Ozone (O3) is an atmospheric gas that consists of three oxygen atoms in its structure. Ozone can be found in the stratosphere (upper atmosphere) or troposphere (ground level). Ozone in the stratosphere protects the harmful ultraviolet radiation of the sun from reaching the earth while the ozone in the troposphere is harmful as it causes respiratory ailments.

Ozone in the troposphere is regarded a secondary pollutant because it is formed from the chemical combination of primary pollutants in the atmosphere. These primary pollutants react to produce ozone in the presence of sunlight. They are called OZONE PRECURSORS and they include Nitrogen oxides, volatile organic compounds and carbon monoxide.

These ozone precursors emanates from engine exhaust in vehicles, industrial emissions, refineries, chemical deposit etc.

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.