Hi people, I was in shock this morning after listening to the press review with a caption “ACID RAIN COMING- saying acid rain is expected in Lagos and Port Harcourt. As an environmentalist/scientist I am of the opinion that people should have information on a situation before making publication. Also, our press should do proper investigation before going into publication. For the record, according to study, published in November 2009 edition of Atmospheric Chemistry and Physics an international journal, studies by UK scientists have quantified for the first time the potentially harmful emission of air pollutants including carbon monoxide and volatile organic compounds (VOCs) around Lagos in Nigeria. According to Professor Alastair Lewis, director of composition research at the National Centre for Atmospheric Science, professor of atmospheric chemistry at the University of York and one of the paper's authors. 'It gives us a snapshot of what's going on, and lets us give advice on how to improve the situation. In this case, Lagos has very high VOC emissions, and this looks like an obvious area for the government to target.'
The only gas detected to be high is VOC emission. VOCs may be natural or synthetic. Like organic chemicals in general, there are many different compounds which may be classified as VOCs. The compounds the nose detects as smells are generally VOCs. Modern industrial chemicals such as fuels, solvents, coatings, feed stocks, and refrigerants are usually VOCs.
There is no clear and widely supported definition of a VOC. From a chemistry viewpoint "Volatile Organic Compound" can mean any organic compound (all chemical compounds containing carbon with exceptions) that is volatile (evaporating or vaporizing readily under normal conditions). This is a very broad set of chemicals. Definitions vary depending on the particular context. Volatile organic compounds are produced naturally through biological mechanisms such as metabolism. Industrial use of fossil fuels produces VOCs either directly as products (e.g. gasoline) or indirectly as byproducts (e.g. automobile exhaust).
However, Acid rain is rain or any other form of precipitation that is unusually acidic, i.e. elevated levels of hydrogen ions (low pH). It can have harmful effects on plants, aquatic animals, and infrastructure through the process of wet deposition. Acid rain is caused by emissions of compounds of ammonium, carbon, nitrogen, and sulfur which react with the water molecules in the atmosphere to produce acids. "Acid rain" is a popular term referring to the deposition of wet (rain, snow, sleet, fog and cloudwater, dew) and dry (acidifying particles and gases) acidic components. A more accurate term is “acid deposition”. Distilled water, once carbon dioxide is removed, has a neutral pH of 7. Liquids with a pH less than 7 are acidic, and those with a pH greater than 7 are bases. “Clean” or unpolluted rain has a slightly acidic pH of about 5.2, because carbon dioxide and water in the air react together to form carbonic acid, a weak acid (pH 5.6 in distilled water), but unpolluted rain also contains other chemicals.
H2O (l) + CO2 (g) → H2CO3 (aq)
Carbonic acid then can ionize in water forming low concentrations of hydronium and carbonate ions:
2 H2O (l) + H2CO3 (aq) CO32− (aq) + 2 H3O+ (aq)
The most important gas which leads to acidification is sulfur dioxide. Emissions of nitrogen oxides which are oxidized to form nitric acid are of increasing importance due to stricter controls on emissions of sulfur containing compounds. In 1990, the US Congress passed a series of amendments to the Clean Air Act. Title IV of these amendments established the Acid Rain Program, a cap and trade system designed to control emissions of sulfur dioxide and nitrogen oxides.
Note: the most important gases responsible for acid rain or deposition is sulfur dioxide and nitrogen oxides which are usually not high in Lagos environment.
Please reliable information is available for people to known the fact from fallacy. Let stop this misinformation.
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