Chlorofluorocarbons (CFCs) are nontoxic, nonflammable chemicals containing atoms of carbon, chlorine, and fluorine. They are used in the manufacture of aerosol sprays, blowing agents for foams and packing materials, as solvents, and as refrigerants. CFCs are classified as halocarbons, a class of compounds that contain atoms of carbon and halogen atoms. Individual CFC molecules are labeled with a unique numbering system. For example, the CFC number of 11 indicates the number of atoms of carbon, hydrogen, fluorine, and chlorine (e.g., CCl3F as CFC-11). The best way to remember the system is the ‘rule of 90’ or add 90 to the CFC number where the first digit is the number of carbon atoms (C), the second digit is the number of hydrogen atoms (H), and the third digit is the number of fluorine atoms (F). The total number of chlorine atoms (Cl) is calculated by the expression: Cl = 2(C + 1) – H – F. In the example, CFC-11 has one carbon, no hydrogen, one fluorine, and therefore three chlorine...
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Bibliography
Albritton, D. L., Watson, R. T., and Aucamp, R. J. (eds), 1995. Scientific Assessment of Ozone Depletion: 1994. Geneva: World Meteorological Organization, 451 pp.
Cagin, S., and Dray, P., 1993. Between Earth and Sky: How CFCs Changed our World and Threatened the Ozone Layer. New York: Pantheon Press, 512 pp.
Elkins, J. W., Thompson, T. M., Swanson, T. H., Butler, J. H., Hall, B. D., Cummings, S. O., Fisher, D. A., and Raffo, A. G., 1993. Decrease in the growth rates of atmospheric chlorofluorocarbons 11 and 12. Nature, 364, 780–3.
Farman, J. C., Gardiner, B. G., and Shanklin, J. D., 1985. Large losses of total ozone in Antarctica reveal seasonal ClOx/NOx interaction. Nature, 315, 207–10.
McElroy, M. B., Salawitch, R. J., Wofsy, S. C., and Logan, J. A., 1986. Reductions of Antarctic ozone due to synergistic interactions of chlorine and bromine. Nature, 321, 759–62.
Midgley, T., and Henne, A., 1930. Organic fluorides as refrigerants. Ind. Eng. Chem., 22, 542–7.
Molina, M. J., and Rowland, R. S., 1974. Stratospheric sink for chlorofluoromethanes: chlorine atom catalyzed destruction of ozone. Nature, 249, 810–14.
Montreal Protocol, 1987. Montreal Protocol on Substances that Deplete the Ozone Layer. New York: United Nations Environmental Programme (UNEP), 15 pp.
Montzka, S. A., Myers, R. C., Butler, J. H., Cummings, S. C., and Elkins, J. W., 1993. Global tropospheric distribution and calibration scale of HCFC-22. Geophys. Res. Lett., 20, 703–6.
Montzka, S. A. Myers, R. C., Butler, J. H., Elkins, J. W., Lock, L. T., Clarke, A. D., and Goldstein, A. H., 1996. Observations of HFC-134a in the remote troposphere. Geophys. Res. Lett., 23, 169–72.
Prinn, R. G., Weiss, R. F., Miller, B. R., Huang, J., Alyea, F. N., Cunnold, D. M., Fraser, P. J., Hartley, D. E., and Simmonds, P. G., 1995. Atmospheric trends and lifetimes of CH3CCl3 and global OH concentrations. Science, 269, 187–92.
Solomon, S., Garcia, R. R., Rowland, R. S., and Wuebbles, D. J., 1986. On the depletion of Antarctic ozone. Nature, 321, 755–8.
Toohey, D. W., Avallone, L. M., Lait, L. R., Newman, P. A., Schoeberl, M. R., Fahey, D. W., Woodbridge, E. L., and Anderson, J. G., 1993. The seasonal evolution of reactive chlorine in the northern hemisphere stratosphere. Science, 261, 1134–6.
Waters, J., Froidevaux, L., Read, W., Manney, G., Elson, L., Flower, D., Jarnot, R., and Harwood, R., 1993. Stratospheric ClO and ozone from the Microwave Limb Sounder on the Upper Atmosphere Research Satellite. Nature, 362, 597–602.
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Elkins, J.W. (1999). Chlorofluorocarbons (CFCs). In: Environmental Geology. Encyclopedia of Earth Science. Springer, Dordrecht. https://doi.org/10.1007/1-4020-4494-1_55
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