What is acid rain made of?

 

Acid rain components

Acid rain consists of a mixture of nitric (HNO3) and sulfuric (H2SO4) acids, resulting from the reaction of sulfur dioxide (SO2) and nitrogen oxides (NOX) emissions through atmospheric air and currents.  wind with water, oxygen and other chemical compounds. Where nitric acid and sulfuric acid mix with water later, and it falls as acid rain on the ground, and these reactions can be explained by the following chemical equations:

Sulfur dioxide reaction to produce sulfuric acid:

• SO2 + H2O → H2SO4

•   H2SO4 →← H+ + HSO4- →← 2H+ + SO4-2

The reaction of nitrogen oxides to produce nitric acid:

• NO2 + H2O → HNO3

• -HNO3→ H+ + NO3

Pure water is a neutral substance, it is neither acidic nor basic, as its pH value is 7, while the pH of clean rain under normal conditions is between 5.0-5.5, which means that ordinary rain is slightly Acidic, while the number reaches the The pH of the rain has dropped Acid to 4, and a decrease in pH from 5 to 4 means that the acidity increased tenfold.

Sources of the components of acid rain

The sources of the components of acid rain are due to the sources of sulfur dioxide and nitrogen oxides produced by human and natural activities, and blow with the wind over long distances, causing acid rain to damage large areas, and not only in the areas close to the emission source of these oxides, here is an

Sources of sulfur dioxide emissions:

 Sulfur dioxide emissions are responsible for 60-70% of acid precipitation occurring worldwide.

Human activities: 

Human activities contribute to nearly 90% of sulfur dioxide emissions, and include coal burning activities, where coal contains 2-3% sulfur, and sulfur dioxide is released upon combustion, in addition to of metal sulfide ore smelting processes.   To obtain pure metals, this method is widely used to obtain nickel, copper and zinc metals. Combustion processes in industrial activities produce 69.4% of sulfur dioxide while transportation produces 3.7%.

Natural activities:

 Natural activities are responsible for 10% of SO2 emissions, including volcanic activities. Volcanic activities can release a large amount of sulfur dioxide into the atmosphere when they erupt, along with decaying organic matter, decaying vegetation, and sea spray.   In addition to phytoplankton and zooplankton.

NOx emission sources: NOx emission sources include:

   Human activities: 

They are the main reason for the emission of most nitrogen oxides into the atmosphere, since 95% of them are produced through various activities, including: Chemical industries produce, such as the production of fertilizers , as well as extremely high temperature processes such as combustion.  in car engines and electric power generators, 25% of these emissions.

Natural Activities:

 Natural activities alone produce 5% of nitrogen oxide emissions, and include volcanic activities, forest burning, and lightning, as well as bacterial activities in the soil.

An overview of acid rain and its different forms

Acid rain has been a widespread environmental problem since the 19th century, referring to the different ways in which acids fall from the atmosphere to the Earth's surface, and acid precipitation represents the most accurate concept to describe these ways, since includes both wet and dry.  ways they fall acids in the soil.

Wet precipitation includes snow, fog, and acid rain, as it falls on the earth's surface and flows through land and water bodies, and causes effects and damage to various animals and plants, but it is observed that gravity The impact of acid rain on wildlife depends on several factors, including; The pH of the water, the type of organisms the rain reaches, including fish, trees, and other water-dependent organisms, as well as the chemistry and buffering capacity of the soil. 

  As for dry precipitation, it refers to particles and acid gases that fall to the ground where they are carried by the winds and reach buildings, trees and cars, and it is observed that about 50% of the acids in the atmosphere fall to the ground.  Land through this type of precipitation. It is also possible that rain that falls later mixes with particles and gases that have accumulated on surfaces, making the composition of the rain more acidic.