“The rainwater which contains a large amount of poisonous acids like sulphuric acid, sulphurous acid, nitrous acid and other pollutants is known as the Acid Rain.”
Formation of Acid Rain
As evident from the definition, Acid rain is caused by a chemical reaction that begins when compounds like sulphur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain. Sulphur dioxide and nitrogen oxides dissolve very easily in water and can be carried very far by the wind. As a result, the two compounds can travel long distances where they become part of the rain, sleet, snow, and fog that we experience on certain days.
Human activities are the main cause of acid rain. Over the past few decades, humans have released so many different chemicals into the air that they have changed the mix of gases in the atmosphere. Power plants release the majority of sulphur dioxide and much of the nitrogen oxides when they burn fossil fuels, such as coal, to produce electricity. In addition, the exhaust from cars, trucks, and buses releases nitrogen oxides and sulphur dioxide into the air. These pollutants cause acid rain.
The main causes of acid rain are as follows:
Lightning strikes (cause nitrogen molecules to be oxidized)
Combustion of hydrogen sulphide (hydrogen sulphide is formed from the breakdown of sulphates in organic matter in the absence of oxygen- anaerobic conditions). This reaction forms sulphur dioxide.
- Combustion engines (car, airplanes etc.)
- Burning of fossil fuels and coal
- Some mineral ores contain sulphur dioxide, and this is released when the minerals are processed.
Effect Of Acid Rain:
i) Kills flora and fauna
ii) Damages the buildings
iii) Causes skin cancer
iv) Increases the acidity of the soil
v) Kills fish and other aquatic animals
vi) Pollutes the water
vii) Causes spotting of leaves
viii) Causes corrosion of metal, painted surfaces and even stone buildings and monuments.
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