What is Acid Rain?
Rainfall made so acidic by atmospheric pollution that it causes environmental harm, mainly to forests and lakes.
pH of Acid Rain
The pH scale ranges from 0-14. Normal rain water is slightly acidic and has a pH range of 5.3-6.0. Acid rain has pH lower than that of normal rainfall.
How are they formed?
Occurs when compounds like Sulfur Dioxide and Nitrogen Oxides react with water and oxygen to form acidic pollutants.
These acidic pollutants dissolve in water vapour and is carried by air away from the source before it falls as acid rain.
Causes of Acid rain
Natural activity, such as volcanoes and decaying vegetation.
Human activities are the main cause of acid rain, fossil fuel combustion to produce electricity, car exhausts etc emit a lot ofnitrogen oxides and sulfur dioxide into the air.
Sources of Acid Rain
A mixture of wet and dry deposition (deposited material) from the atmosphere containing higher than normal amounts of nitric and sulfuric acids.
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