Acid Rain

When pollutants(gases) from factories react with water vapour present in the atmosphere it forms acid 

And when this acid drops down with rain,it is known as Acid rain.

Example

Sulphur Dioxide    +    Water Vapour    =     Sulphuric Acid

Nitrogen Dioxide  +     Water Vapour    =     Nitric Acid

How does Acid Rain Occur?

The burning of fossil fuels, petrol and diesel releases harmful gases in atmosphere like Sulphur Dioxide and Nitrogen Dioxide 

These gases get mixed with water vapour present in the atmosphere.

And form harmful acids like Sulphuric Acid and Nitric Acid

These acids dissolve in rainwater and fall on the earth in the form of rainwater

This is called Acid Rain

Harmful effects of Acid Rain

Acid rain effects both living and non living things 

Plants

• It damages the leaves of the plants and decreases the fertility of the soil

Animals and Humans

• Acids present in the acid rain makes it difficult for humans and animals to breathe

• Aquatic Life
  Acid rain causes the water in ponds, lakes and rivers to become more acidic and hence unsuitable for survival of aquatic plants and animals

• Non Living things 

Monuments and building get discoloured due to acid rain

Example - Acid Rain has caused white marble of Taj Mahal to turn yellow

Refer to NCERT Question 6