Question

What is the source of sulphur dioxide emissions?
(A) Agricultural forms
(B) Petroleum Refineries
(C) Hydroelectric power stations
(D) None of the above

Answer 1

Hint: Sulphur dioxide is a very harmful pollutant that causes Acidification, Eutrophication and air pollution. The major sources of sulphur dioxide are power plants that burn fossil fuels containing sulphur to produce electricity, Smelting of mineral ores containing sulphur and burning of sulphur-containing fuels by large vehicles, ships, and large equipment

Complete answer:
Sulphur dioxide emissions are given out by those industries which aid in refining sulphur containing products. One of the major industries that has to deal with sulphur is petroleum refineries which employ different catalytic processes to remove the sulphur from the gasoline and diesel. The method of removal of sulphur from petrol is known as desulphurization which gives immense sulphur dioxide into the atmosphere as a pollutant.
The most dangerous environmental impact caused by sulphur dioxide is the formation of acid rain. Acid rain occurs when the sulphur dioxide emitted from various sources combine with water vapour in the atmosphere, forming sulphuric acid. This then falls to the ground as acid rain causing acidification, Eutrophication and various other adverse effects on the environment.
Thus we can say that the correct option is option (B).

Note:
Acid Rain can also be caused due to another pollutant known as oxides of nitrogen or nitrogen dioxide and nitrogen oxide. They are mainly produced by burning of fossil fuels and vehicular emissions. These pollutants combine with water in the atmosphere forming nitric acid which is another component of acid rain.