Acid rain is one of the repercussions of pollution in the air. It is a form of precipitation containing a pH of about 5.2 or below. The emissions of sulfur dioxide (SO2) and nitrogen oxides from human activities produce it, mainly from the combustion of fossil fuels.
The Royal Society of Chemistry believes Scottish chemist Robert Angus Smith is the “father of acid rain” where he discovered the word acid rain in 1852 while comprehending rainwater chemistry adjoining industrial towns in England and Scotland. Things such as power stations, factories and cars all burn fuels and lead to polluting gases. Some of these gases, mainly nitrogen oxides and sulphur dioxide, react with the small droplets of water in clouds to create sulphuric and nitric acids. The rain from these clouds then comes out as fragile acid, called “acid rain”.
Scientists measure how much acid is in rain or a body of water by undertaking the pH scale. There are 14 numbers mentioned on it, ranging from 0 to 14. If a lake has a low pH, there is a large amount of acid in the lake. If a lake contains a pH 8 or above, it is termed alkaline, implying there is not much acid. A body of water or substance with a pH of 7 is considered neutral as it is in the middle.
Rain is invariably slightly acidic because it combines with natural oxides in the air. Rain, which is not polluted, includes a pH value between 5 and 6. When the air becomes more polluted with nitrogen oxides and sulphur dioxide, the acidity can be increased to a pH value of 4. Some instances of rain have been registered as pH2.
Acid rain has varied forms, namely snow, mists and dry dust. There are times when the rain comes many miles from the origin of pollution, but wherever it comes, it can have a hazardous impact on trees, soil, buildings and water.
Its deposition occurs in two ways such as wet and dry. Wet deposition is any type of precipitation that separates acids from the atmosphere and is positioned on the earth’s surface. When there is no precipitation, dry deposition of polluting particles and gases remains on the ground through dust and smoke.
Consequences of acid rain
- It severely affects agriculture as it changes the composition of the soil.
- It leads to respiratory issues in animals and humans.
- It leads to the corrosion of water pipes which results in the leaching of heavy metals, namely lead, iron and copper, into drinking water.
- It annihilates buildings and monuments composed of stones and metals.
- Uttar Pradesh’s Agra has numerous industries that release Sulphur and Nitrogen oxides in the atmosphere. People continue to adopt low-quality coal and firewood as domestic fuel, which creates a problem.
