Acid Rain and Its Chemistry

Acid Rain and its Chemistry

Acid rain is a type of pollution that is becoming a major threat to our planet and is need of attention. Acid rain has significantly increased ever since the industrial revolution, and now around the world, countries like Russia, China, and those in Europe are facing increasing levels of acidity in their rain. Not only is it becoming more acidic but it is also spreading by the pumping of sulfuric gasses deeper into the atmosphere from of the use of taller smokestacks at factories, which were made to reduce acid rain in local areas. Acid rain, is basically any precipitation like rain, fog or snow that is abnormally acidic with a pH around 5 - 5.5. Although pure water has a pH of 7, unpolluted rainwater has a pH of 5.6 – 6 because of carbon dioxide in the atmosphere reacting with the water and forming a weak carbonic acid. The acidity in the precipitations (rain, snow, fog) come from gasses released into the atmosphere by industrial factories, the combustion of fossil fuels, and even volcanoes. These gasses, sulfur dioxide and various nitrogen oxides, chemically react with the water vapors and oxygen in the atmosphere forming acidic vapors that will eventually rain back down on people, cities, and the environment. Normal rain water is a little acidic because of the presence of carbon dioxide. The carbon dioxide reacts with the water molecules to form a very weak acid named carbonic acid. Once this acid mixes with water it can then ionize to form low concentration ions that won’t corrode or damage. The process of the sulfuric gasses and nitrogen containing gasses to acid rain is much different and varies in complexity. For nitrogen dioxide, the only one thing has to happen and that is that it has to react with hydroxide to form nitric acid and then mix with the water molecules. Sulfur dioxide is a little more complicated and long. First the sulfur dioxide has to also react with hydroxide and then with oxygen to form sulfur trioxide gas. This sulfur trioxide quickly reacts with the water vapor particles to form sulfuric acid which mixes with the rest of the water. When these acids mix with water and rain down its called wet deposition, but when the sulfuric or nitric acid don’t mix with water, like in very dry places, the acid particles come down and stick to surfaces. The affects of acid rain on stone sculptures and buildings can be very damaging because the acidic rain accelerates erosion and it is almost impossible to fix. In cities acid rain can decay and erode paint from buildings and also make their structures weaker, which could cause major problems. The way the acid rain erodes buildings and statues that are made of limestone, sandstone, granite, or marble is that the sulfuric acid in the rain reacts with the calcium in the stones and forms gypsum, which crumbles off. Another example would be gravestones. Many times we can’t read gravestones because they are too eroded. This would be caused by acid rain. Throughout the world, the premature erosion and loss of statues and buildings is a concern because many of these things have historical value or are of great importance to certain cultures. The affects of acid rain on the environment is very terrible and if they continue to increase, we will be badly affected also. Acid rain or snow can turn lakes, streams or rivers acidic. As a result of this acidity, the lakes, streams, and rivers’ ecosystem chain can break or collapse, causing mass amounts of deaths. Acid rain also has a very negative effect on land with trees, plants, soil, and even entire forests. When acid rain enters soil, a chemical reaction occurs that causes the rain to take away the soils nutrients and minerals, causing the soil to be greatly altered. During the reaction the hydronium ions of the acid activate poisons like aluminum and suck out nutrients like magnesium. It is in this way that trees, plants, and even forests are halted of growth, and sometimes even destroyed. Overall, acid rain has the potential of becoming a world-wide emergency but because of chemistry, solutions are being researched and developed. For example, knowing that sulfuric gasses cause acid rain, some factories use limestone to absorb the sulfur out of the gas and then either sell the gypsum that was formed or throw it away. Chemistry is the key to solving this problem because acid rain is made up of atoms and molecules, and the way it damages is by chemical reactions. If no one tries to stop the spread and growth of acid rain many of our beautiful historical buildings and sculptures may be lost prematurely as a result of speeded erosion from the acids. Also, the environment would be badly damaged from the waters becoming too acidic for animals and the soil would be too depleted to support any life. By knowing how acid rain is formed and how it destroys, we can possibly help stop it.

Bibliography
1.
National Biological Service, USGS. (2009) Acid Rain: Do You Need to Start Wearing a Rain Hat? Retrieved May 22, 2009, From USGS, Website: http://ga.water.usgs.gov/edu/acidrain.html
2.
Environmental Protection Agency. (2002) What is acid Rain and What Caused it? Retrieved May 22, 2009, from Almanac of policy issues. Website: http://www.policyalmanac.org/environment/archive/acid_rain.shtml
3.
Rachel Casiday and Regina Frey. (1998) Acid Rain Retrieved May 22, 2009, from Washington university. Website: http://www.chemistry.wustl.edu/~edudev/LabTutorials/Water/FreshWater/acidrain.html
4
U.S. Department of Energy. (2000), Acid Rain—A contemporary world problem retrieved May 22, 2009, from geocities, http://www.geocities.com/narilily/acidrain.html

Bibliography: 1. National Biological Service, USGS. (2009) Acid Rain: Do You Need to Start Wearing a Rain Hat? Retrieved May 22, 2009, From USGS, Website: http://ga.water.usgs.gov/edu/acidrain.html 2. Environmental Protection Agency. (2002) What is acid Rain and What Caused it? Retrieved May 22, 2009, from Almanac of policy issues. Website: http://www.policyalmanac.org/environment/archive/acid_rain.shtml 3. Rachel Casiday and Regina Frey. (1998) Acid Rain Retrieved May 22, 2009, from Washington university. Website: http://www.chemistry.wustl.edu/~edudev/LabTutorials/Water/FreshWater/acidrain.html 4 U.S. Department of Energy. (2000), Acid Rain—A contemporary world problem retrieved May 22, 2009, from geocities, http://www.geocities.com/narilily/acidrain.html