Acid Rain

Acid rain, or acid deposition, is a broad term that includes any form of precipitation with acidic components, such as sulfuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms.  This can include rain, snow, fog, hail or even dust that is acidic. 

Acidity is determined on the basis of the pH level of the water droplets. Normal rain water is slightly acidic with a pH of 5.6, because carbon dioxide and water present in the air react together to form carbonic acid, which is a weak acid. When the pH level of rain water falls below this range, it becomes acid rain (Typically acid rain has a pH value of 4.0).

CAUSES OF ACID RAIN

Natural Causes

Natural sources comprise of Volcanoes as Sulfur dioxide can be emitted into the atmosphere.

Some natural processes also contributes such as soil, forest fires, volcanic action and lightning these contributes to Nitrogen oxide emissions.

Anthropogenic Causes

It causes due to emissions from industries, fossil fuels burning all contribute to the emissions of Nitrogen Dioxide and Sulfur dioxide the 2 major gases for the formation of acid rain.

Reaction of ACID RAIN


Reaction to form nitric acid

Reaction to form sulfuric acid

Formation of acid rain

Types of acid rain

Dry deposition

It occurs when acidic chemicals are released in the air and weather is dry so the acid pollutants slips back in the form of dust or smoke and fall to the ground as dry particles.

Wet deposition

Wet deposition is what we most commonly think of as acid rain. The sulfuric acid and nitric acids formed in the atmosphere fall to the ground mixed with rain, snow, fog, or hail.