What are CFCs?

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What are CFCs?

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Chlorofluorocarbons, of CFCs, are chemical compounds developed as an alternative to more dangerous chemicals for a variety of applications. They were developed in the 1930s for use mainly in refrigeration and as a substance for propellants in products such as aerosol cans. However, while they pose less of a direct threat to individuals, they can provide an indirect threat to the global environment. CFCs contain several organic compounds and formulas may vary. However, the most common organic compounds used are carbon, fluorine, chlorine and hydrogen. These compounds are not toxic and not flammable, which made them ideally suited for use as propellants and other home uses. One of the trade names of CFCs is freon, which is used as a coolant not only for refrigerators but for air conditioning units, both in vehicles and in homes. CFCs, after their creation in the 1930s, quickly became the product of choice for many manufacturers. However, as CFCs increased their market presence, many did

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Chlorofluorocarbons, or CFCs, were developed in the 1930s. Man-made CFCs have been the main cause of ozone depletion in the stratosphere. CFCs have a lifetime of about 20-100 years and can therefore continue to destroy ozone for a long period. One CFC molecule can result in the loss of 100,000 ozone molecules. CFCs are made up of carbon, chlorine and fluorine atoms and there are a number of different types. CFCs have been widely used as: • solvents in cleaners; • coolants in refrigeration and air conditioning; • blowing agents in the production of foam (e.g. fire extinguisher); • propellants in aerosols. The pie chart below shows the uses of CFCs in various products before countries agreed in 1987 to ban them because of the dangers they posed to the ozone layer.

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Experimental data show that chlorine and other halogens are a big part of ozone depletion. But there are only a couple of natural sources of the Cl radical and almost none of any other halogen. Where does it all come from? Humans produce some of the main sources of chlorine and bromine radicals through chemicals called chlorofluorocarbons and halons. CFCs contain carbon and halogens, especially fluorine and chlorine. Halons are like CFCs, but they contain bromine instead of or as well as chlorine. CFCs and halons are molecules that have strong bonds, which make them very stable. Chlorofluorocarbons are insoluble, nontoxic and have very low reactivity. For this reason, CFCs were considered very safe. CFCs could not be disposed through pollution in the troposphere or dissolved in rivers. In the 19070’s , the amount of CFCs were measured. The amounts of CFCs were almost equal to the total amount of the chemicals ever manufactured! So what happened to the amount that had disappeared? CFCs

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