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|Section2= |Section3= }} Trichlorotrifluoroethane, also called 1,1,2-Trichloro-1,2,2-trifluoroethane or CFC-113 is a chlorofluorocarbon. It has the formula Cl2FC-CClF2. This colorless gas is a versatile solvent. It has attracted much attention for its role in the depletion of stratospheric ozone.〔Günter Siegemund, Werner Schwertfeger, Andrew Feiring, Bruce Smart, Fred Behr, Herward Vogel, Blaine McKusick “Fluorine Compounds, Organic” Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. 〕 The amount of CFC-113 in the atmosphere has remained at about 80 parts per trillion, since the early 1990s. It is isomeric with 1,1,1-Trichloro-2,2,2-trifluoroethane, known as CFC-113a, which has the structural formula CF3-CCl3. The Montreal Protocol in 1987 called for the phase out of all CFC’s, including CFC-113 by 2010. ==Atmospheric reactions== CFC-113 is a very unreactive chlorofluorocarbon. It remains in the atmosphere about 90 years, sufficiently long that it will cycle out of the troposphere and into the stratosphere. In the stratosphere, CFC-113 can be broken up by ultraviolet radiation (where sunlight in the 190-225 nm (UV) range), generating chlorine radicals (Cl•), which initiate degradation of ozone requiring only a few minutes:〔()〕 :C2lF3Cl3 → C2lF3Cl2 + Cl• :Cl• + O3 → ClO• + O2 This will occur in only half a second. It is followed by: :ClO• + O → Cl• + O2 The process regenerates Cl• to destroy more O3. The Cl• thus is a catalyst, which destroy an average of 100,000 O3 molecules during its atmospheric lifetime of 1–2 years. In some parts of the world, these reactions have significantly thinned the Earth's natural stratospheric ozone layer that shields the biosphere against solar UV radiation; increased UV levels at the surface can cause skin cancer or even blindness.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「1,1,2-Trichloro-1,2,2-trifluoroethane」の詳細全文を読む スポンサード リンク
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