Acid Rain on our Environment
Acid rain or acid deposition is the major pollutants of our environment form by precipitation of acidic components like sulfur trioxide or nitric oxide comes down in the atmosphere as sulfuric or nitric acid rain, snow, fog, hail or even dust. The formation of acid rain from different sources causes to effect general plants, aquatic life, and archeological specimen in the world. Therefore, we need to study scientific environmental chemistry learning to solve problems of acid rain to save our environment. Acid rain formed mainly by the emission of SOx and NOx from different heat sources like coal, oils or automobile engine burning, etc. Natural rain-water also slightly acidic (pH scale = 5.6) because it contains some atmospheric carbon dioxide that forms the carbonic acid solution with water.
Sulfur dioxide is a major pollutant for the study of environmental chemistry. Sulfur dioxide released by burning oil and coal and industry by the formation of sulfuric acid which damages our plant, animal, and humans life. About 200 million tonnes of the mass of this gas released over the world from industries and equal amounts released by natural processes.
Formation of Sulphuric Acid in Environment
Sulfur dioxide partially oxidation to sulfur trioxide in the air by the photolytic or catalytic process initiated by ozone, hydrocarbon, nitrogen oxides, and soot or dust. This sulfur trioxide reacts with rainwater or moisture gives sulfuric acid. This acid rain comes down the atmosphere in the form of sulfuric acid rain, snow.
2SO3 + O2 → 2SO3
SO2 + O3 → SO3 + O2
SO3 + H2O → H2SO4
Formation of Nitric Acid in Environment
The smoke released by the automobiles engines contains greenhouse gases nitrogen dioxide. This smoke obtained by the thermodynamic combustion of petrol or diesel in engines. Many chemical plants like explosives or nitrogenous fertilizers produce nitrogen dioxide. Large amounts of sulfur or nitrogen dioxide also emitted from power plants and many industrial processes. These mixtures containing sulfur or nitrogen dioxide is called flue gases mixture. The nitrogen dioxide produces from the above sources reacts with the rainwater or moisture in the presence of oxygen or ozone to produces nitric acid rain or snow.
2NO + O2 → 2NO2
NO + O3 → NO2 + O2
NO2 + NO3 → N2O5
N2O5 + H2O → 2HN03
Causes and Effects of Acid Rain
Acid rain form from nitrogen dioxide and sulfur dioxide serves many impacts of our environment like animal or plant life.
- Acid rain has served ecological impacts and eating up limestone and marble of the bridges, statues, monuments, tombstones, and other cultural artifacts. Due to the corrosive nature, these pollutants decolorize building materials like limestone, marble, roof slate, and metals.
- Fabrics, leather, paper, and paints undergo fading of thair color in the presence of SO2 and NO2.
- The negative effect of acid rain increases the acidity of the soil. This changes the solubility of the different metal element salt in soil mainly the aluminum salt in the soil.
- The effects of acid rain are seen in the fish, plants, and humans life of our environment. Therefore, the increasing acidity of the water fertility of fishes decreases, or young fishes are dying.
- It does not affect humans directly. The concentration of many dangerous metal elements particles is increased through the acidic water. When we drink such water, it transported to our body which affects our lungs. It also affects our skin, cells, and neuronal system of our body.
Control the Emission of SO2 and NO2
Nitrogen dioxide can be controlled by reducing with air in the presence of the platinum catalyst produces nitrogen and ammonia molecule. Therefore, before this enters the atmosphere this process may be applied. The density of sulfur dioxide decreases by treating the flue gases with the slurry of calcium carbonate which absorbed the SO2 gases due to the formation of CaSO3. But the process is quite economical. SO2 may also be reduced partially by desulphurization of coal and Naptha or using natural gas in place of coal. But this technical information for the solutions of acid rain not fully utilizes in practice in many cases.
Scientific Solutions for Acid Rain
- Increasing the use of nuclear energy, wind, and solar energy, hydroelectric energy unit for the source of electricity.
- Using requisite technology for reducing the emission of NOx and SOx from the thermal power plant or different production factory.
- Decreasing the use of fossil fuel in our daily life.
- Using technology in vehicles for reducing the emission of NOx.