Acid Rain !!!!

In this modern day, there is a constant conflict between the industrial society and the environment. Acid rain is the result of human activities that causes the build up of acid that occurs as wet deposition in rain, snow or fog and as dry deposition on solid particles. One of the main forms of acid deposition is through the transformation of sulphur dioxide and nitrogen oxides into dry or moist secondary pollutants such as sulphuric acid (H₂SO₄), ammonium nitrate (NH₄NO₃) and nitric acid (HNO₃). The oxidation of SO₂ forms sulphur trioxide that will form sulphuric acid (H₂SO₄) on contact with water, including any in the atmosphere.  The reaction of N₂ and O₂ will form nitrogen oxides. NO is formed during combustions, especially in car engines and electric power plants. It forms NO₂ and HNO₃ in the air in the process that creates smog. At night, NO_x is then converted to N₂O₅, which hydrolyzes to HNO₃ in the presence of water. The strong acids such as H₂SO₄ and HNO₃ are a main concern as it dramatically affects the ph of rain.
These acidic particle and vapours occur as the pollutants are transported in the atmosphere over a wide distance. Acidic particles and vapours are deposited via two processes which are wet and dry deposition. Wet deposition is acid rain, the process by which acids with a pH normally below 5.6 are removed from the atmosphere in rain, snow, sleet or hail. Dry deposition takes place when particles such as fly ash, sulphates, nitrates, and gases, are deposited on, or absorbed onto, surfaces. The gases can then be converted into acids when they contact water.

Acid rain affects the environment in many ways. Certain shellfish and fishes die at pH values between 4.5 and 5.0 and at pH 5, most fish eggs cannot hatch. This loss of fish is a major concern that has been around for awhile. Forests have also been affected as the acid rain removes nutrients and releases toxic substances from the soil. Even if the soil is buffered, acidic fog and clouds can remove essential nutrients from the surface of leafs.  Aluminosilicates that make up most soils are extremely insoluble in water. The Al³⁺ ion is bonded to OH^- and O^2- ions in complex structures. The continual contact with the H₃O⁺ in acid rain causes these ions to react with bound Al³⁺ and dissolve. This ion is toxic to fish and will also carry away ions that serve as nutrients for plants and animals. Besides that, acid rain also dissolves calcium carbonate in marble and limestone of buildings and monuments. However, these same properties are responsible for saving lakes bounded by limestone-rich soil. It keeps the lake at a relatively stable pH, where it remains mildly basic.


ACID RAIN VIDEO....