Introduction:
Acid rain refers to the deposition of acidic substances in the form of rain, snow, fog, or dry particles onto the Earth's surface. The primary cause of acid rain is industrial burning of coal and other fossil fuels.

Main Cause: Industrial burning of coal and other fossil fuels
The combustion of coal and fossil fuels in industries releases large amounts of sulfur dioxide (SO2) and nitrogen oxides (NOx) into the atmosphere. These pollutants react with water, oxygen, and other chemicals to form sulfuric acid (H2SO4) and nitric acid (HNO3). When it rains, these acids are carried down to the Earth's surface, resulting in acid rain.

Industrial Activities:
Industrial activities such as power plants, factories, and vehicles contribute significantly to the emission of sulfur dioxide and nitrogen oxide. Coal-fired power plants are one of the major sources of sulfur dioxide emissions. When coal is burned, sulfur compounds present in coal are released into the atmosphere. Similarly, vehicles and factories emit nitrogen oxides during the combustion of fossil fuels.

Chemical Reactions:
When sulfur dioxide and nitrogen oxides are released into the atmosphere, they undergo a series of chemical reactions. Sulfur dioxide reacts with oxygen and water vapor to form sulfuric acid. Nitrogen oxides react with atmospheric moisture to produce nitric acid. These acids are then carried by wind currents and deposited onto the Earth's surface through precipitation.

Environmental Impact:
Acid rain has detrimental effects on the environment. It can damage forests, lakes, and aquatic ecosystems. When acid rain falls on trees and plants, it damages their leaves, inhibiting their ability to photosynthesize and grow. Acid rain also leaches essential nutrients from the soil, affecting the overall health of plants and vegetation.

Human Health Impact:
Acid rain can have adverse effects on human health. When acid rainwater is consumed or comes into contact with skin, it can cause respiratory issues, skin irritation, and other health problems. Additionally, acid rain can contaminate drinking water sources, posing a risk to human consumption.

Conclusion:
The main cause of acid rain is the industrial burning of coal and other fossil fuels. The release of sulfur dioxide and nitrogen oxides during the combustion process leads to the formation of sulfuric acid and nitric acid, which are then deposited onto the Earth's surface through precipitation. Acid rain has significant environmental and human health impacts, making it crucial to reduce emissions from industrial activities to mitigate its effects.