e 23 million tons of nitrogen oxides into the atmosphere in the course of the year. Transportation sources account for 40%; power plants, 30%; industrial sources, 25%; and commercial institutions and residues, 5%. What makes these figures particularly distributing is that nitrogen oxide emissions have tripled in the last thirty years. CAUSES Acid rain is a cancer eating into the face of Eastern Canada and the North Eastern United States. One of the main causes of acid rain is sulphur dioxide. Natural sources which emit this gas are volcanoes, sea spray , rotting vegetation and plankton. However, the burning of fossil fuels, such as coal and oil, are largely to be blamed for approximately half of the emissions of this gas in the world. When sulphur dioxide reaches the atmosphere, it oxidizes to first form a sulfate ion. It then becomes sulphuric acid as it joins with hydrogen atoms in the air and falls back down to earth. Oxidation occurs the most in clouds and especially in heavily polluted air where other compounds such as ammonia and ozone help to catalyze the reaction, converting more sulphur dioxide to sulphuric acid. However, not all of the sulphur dioxide is converted to sulphuric acid. In fact, a substantial amount can float up into the atmosphere, move over to another area and return to earth unconverted. The following are the stoichiometric equations for the formation of sulphuric acid: S (in coal) + O2„_ SO2 2 SO2 + O2„_ 2 SO3 SO3„_ + H2O H2SO4 Nitric oxide and nitric dioxide are also components of acid rain. Its sources are mainly from power stations and exhaust fumes. Like sulfur dioxide, these nitrogen oxides rise into the atmosphere and are oxidized in clouds to form nitric acid. These reactions are also catalyzed in heavily polluted clouds where iron, manganese, ammonia and hydrogen peroxide are present. In Canada, the main sulfuric acid sources are non-ferrous smelters and power generation. On both sides of the border, cars and trucks are the main sources for nitric acid(about 40% of the total), while power generating plants and industrial commercial and residential fuel combustion together contribute most of the rest. In the air, the sulfur dioxide and nitrogen oxides can be transformed into sulfuric acid and nitric acid, and air current can send them thousands of kilometers from the source. When the acids fall to the earth in any form it will have large impact on the growth or the preservation of certain wildlife. NO DEFENSE One of the direct effects of acid rain is on lakes and its aquatic ecosystems. There are several routes through which acidic chemicals can enter the lakes. Some chemical substances exist as dry particles in the air while others enter the lakes as wet particles such as rain, snow, sleet, hail, dew or fog. In addition, lakes can almost be thought of as the "sinks" of the earth, where rain that falls on land is drained through the sewage systems eventually make their way into the lakes. Acid rain that falls onto the earth washes off the nutrients out of the soil and carries toxic metals that have been released from the soil into the lakes. Another harmful way in which acids can enter the lakes is spring acid shock. When snow melts in spring rapidly due to a sudden temperature change, the acids and chemicals in the snow are released into the soils. The melted snow then runs off to streams and rivers, and gradually make their way into the lakes. The introduction of these acids and chemicals into the lakes causes a sudden drastic change in the pH of the lakes - hence the term "spring acid shock". The aquatic ecosystem has no time to adjust to the sudden change. Areas in Ontario mainly southern regions that are near the Great Lakes, such substances as limestone or other known antacids can neutralize acids entering the body of water thereby protecting it. However, large areas of Ontario that are near the Pre-Cambrian Shield, with quartzite or granite based geolo

Some common words found in the essay are:
H2SO4 Nitric, SO2 NO2, Mountains Hampshire, Eastern United, Indiana Illinois, RAIN Acidity, CONSISTS Canada, Coal Cleaning, Concentric Firing, DYING Acid, acid rain, toxic metals, sulphur dioxide, flue gas, nitrogen oxides, + o2„_, sulfur dioxide, sulfur content, sulphuric acid, suffer dioxide, causes acid rain, dry scrubbing process, flue gas desulfurization, tons suffer dioxide, spring acid shock,
Approximate Word count = 2644
Approximate Pages = 11 (250 words per page double spaced)