Environmental chemistry acid rain

Atmospheric emissions of sulphur dioxide are either measured or estimated at their source and are thus calculated on a provincial or state basis for both Canada and the United States (Figure 2). While much research and debate continues, computer-based simulation models can use this emission information to provide reasonable estimates of how sulphur dioxide and sulphate (the final oxidized form of sulphur dioxide) are transported, transformed, and deposited via atmospheric air masses to selected regions. Such "source-receptor" models are of varying complexity but all are evaluated on their ability to reproduce the measured pattern of sulphate deposition over a network of acid rain monitoring stations across United States and Canada. In a joint effort of the U.S. Environmental Protection Agency and the Canadian Atmospheric Environment Service, eleven linear-chemistry atmospheric models of sulphur deposition were evaluated using data from 1980. It was found that on an annual basis, all but three models were able to simulate the observed deposition patterns within the uncertainty limits of the observations (22). 

In the 20 years since the Brunddand report, great developments have taken place in industries toward sustainable practices. As a case in point, the problem of acid rain, an issue of concern in 1987, has improved to a large extent, thanks to catalytic pollution abatement both in stationary and automotive emissions. Catalysis for Green Chemistry and Engineering will continue to have a cracial role in improving the environmental performance of industry [25-27]. Nowadays, catalytic procedures are often implemented according to the green chemistry... 

Dietrich, D., Schlatter, C., Blau, N. and Fischer, M. (1989). Aluminium and acid rain mitigating effects of NaCl on aluminium toxicity to brown trout (Salmo truttafario) in acid water. Toxicological and Environmental Chemistry 19,17-23. 

Dolan, E. Zhang, Y. Klarup, D. The Distribution Coefficient of Atrazine with Illinois Soils ALaboratory Exercise in Environmental Chemistry, /. Chem. Educ. 1998, 75, 1609-1610. Driscoll, J. A. Acid Rain Demonstration The Formation of Nitrogen Oxides as By-Products of High Temperature Flame in Connection with Internal Combustion Engines, /. Chem. Educ. 1997, 74, 1424-1425. 

Powers, D. C. Higgs, A. T. Obley, M. L. Leber, P. A. Hess, K. R. Yoder, C. H. Analysis of Natural Buffer Systems and the Impact of Acid Rain. An Environmental Project for First-Year Chemistry Students, 7. Chem. Educ. 2005, 82, 274-277. 

J. W. Jones, "Estimating Performance and Costs of Retrofit SO., and NO Controls for Acid Rain Abatement," ACS Extended Abstract Preprint, ACS Division of Environmental Chemistry Meeting (June 5—11,1988, Toronto, Ontario). 

Recognizing Cause and Effect Environmental chemistry has a number of cause-and-effect relationships. Describe these relationships in a) the formation of acid rain, b) ozone depletion. 

It is probably true to say that the term environmental chemistry has no precise definition. It means different things to different people. We are not about to offer a new definition. It is clear that environmental chemists are playing their part in the big environmental issues—stratospheric ozone (C) () depletion, global warming and the like. Similarly, the role of environmental chemistry in regional-scale and local problems—for example, the effects of acid rain or contamination of water resources—is well established. This brief discussion illustrates the clear link in our minds between environmental chemistry and human beings. For many people, environmental chemistry is implicitly linked to pollution . We hope this book demonstrates that such a view is limited and shows that environmental chemistry has a much wider scope. 

Some of these environmental problems are discussed in the Chemistry in Use essay Acid Rain. ... 

After Japan, the most extensive chemistry data set in the Asian region is for China. The Institute of Environmental Chemistry initiated a survey of precipitation chemistry in some cities in the late 1970s, and nationwide surveys have been reported since 1982. The results of these studies show that acid rain occurs in many parts of China, especially in the southwest (Zhao and Sun, 1986 Galloway et al, 1987 Zhao and Xiong, 1988, Naritaetal, 1997). 

Figure 19.12 Formation of acidic precipitation. A complex interplay of human activities, atmospheric chemistry, and environmental distribution leads to acidic precipitation and its harmful effects. Car exhaust and electrical utility waste gases contain lower oxides of nitrogen and sulfur. These are oxidized in the atmosphere by O2 (or O3, not shown) to higher oxides (NO2, SO3), which react with moisture to form acidic rain, snow, and fog. In contact with acidic precipitation, many lakes become acidified, whereas limestone-bounded lakes form a carbonate buffer that prevents acidification.

Nitrogen oxides (NO ) are environmental pollutants that lead to hazards such as acid rain and smog. As much as 15% of the total NO emissions comes from the process of coal utilization [70]. It has been an important problem in coal chemistry to understand the pyrolysis mechanism of nitrogen-containing structures. In addition, the role of nitrogen migration in coal is very complex and has not been understood at the molecular level [71,72]. The formation of NO is considered to occur in two steps the... 

Atmospheric nitrogen cycling plays an important role in a number of key environmental processes, including atmospheric photochemistry and smog, acid rain, climate, stratospheric chemistry, and eutrophication. 

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