CARBON MONOXIDE EMISSIONS |
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Carbon monoxide, chemical formula CO, is a colorless, odorless, tasteless, flammable and highly toxic gas. It is a major product of the incomplete combustion of carbon and carbon-containing compounds. It is less dense than air under ordinary conditions, however it accumulates on the ground, meaning that if poisoning causes loss of consciousness the amount of carbon monoxide inhaled increases and so fatality is radically increased. It is very slightly soluble in water and burns in air with a characteristic blue flame, producing carbon dioxide; it is a component of producer gas and water gas, which are widely used artificial fuels. It is a reducing agent, removing oxygen from many compounds and is used in the reduction of metals, e.g., iron , from their ores. At high pressures and elevated temperatures it reacts with hydrogen in the presence of a catalyst to form methanol. Carbon monoxide is formed by combustion of carbon in oxygen at high temperatures when there is an excess of carbon. It is also formed with a byproduct oxygen by decomposition of carbon dioxide at very high temperatures (above 2,000 °C). It is present in the exhaust of internal-combustion engines, often the exhaust of automobiles, and is generated in coal stoves, furnaces, and gas appliances that do not get enough air. This may be due to insufficient ventilation or other reasons.
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COMBUSTION |
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Combustion or burning is a chemical process, an exothermic reaction between a substance (the fuel) and a gas (the oxidizer), usually O2, to release heat. In a complete combustion reaction, a compound reacts with an oxidizing element, and the products are compounds of each element in the fuel with the oxidizing element. For example:
CH4 + 2 O2 → CO2 + 2 2O + heat
CH2S + 6 F2 → CF4 + 2 HF + SF6 + heat
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POLLUTION |
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Pollution is the release of environmental contaminants. Carbon monoxide, sulfur dioxide, chlorofluorocarbons (CFCs), and nitrogen oxides produced by industry and motor vehicles are common air pollutants. Sunlight converts nitrogen oxides and hydrocarbons to ozone or smog. Water pollutants may consist of a wide range of organic and inorganic chemicals such as heavy metals, petrochemicals, chloroform, and bacteria. Water pollution may also occur in the form of thermal pollution and dissolved oxygen depletion. Soil contamination is an important aspect of environmental pollution; this phenomenon occurs when chemicals are released by spill or underground storage tank leakage. Among the most significant soil contaminants are hydrocarbons, heavy metals, MTBE, herbicides, pesticides and chlorinated hydrocarbons. The U.S., Russia, China and Japan are the world leaders in air pollution emissions; however, Canada is the number two country on a per capita basis.
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