Methane, Chlorofluoro

Figures 4.44 and 4.45 show absorption spectra of some simple chlorofluoro-methanes and ethanes, respectively (Hubrich and Stuhl, 1980). Tables 4.37 and 4.38 give the recommended absorption cross sections for some of these compounds (DeMore et al., 1997). None of these compounds absorb in the actinic region above 290 nm, but do around 180-200 nm, wavelengths only found in the stratosphere. As discussed in Chapter 12, it is photolysis at these short wavelengths to generate atomic chlorine that is responsible, along with bromine and perhaps in some cases, iodine atoms, for the chain destruction of stratospheric ozone.

Like dichloromethane, the fluoro- analogue is weakly flammable, with flammability not revealed by many conventional tests. A new method of measurement is described [1]. The explosion properties with air of both difluoro- and chlorofluoro-methane have been studied [2]. 

OICHLORO-METHANE CHLOROFLUORO-METHANE DIFLUORO-METHANE DIIODOMETHANE FORMALDEHYDE FORMIC-ACID BROMOMETHANE CHLOROMETHANE FLUOROMETHANE IODOMETHANE NITROMETHANE METHYL-NITRfTE METHYL-NITRATE METHANE METHANOL METHANETHIOL METHYLAMINE TETRA... 

Simon P.C., D. Gillotay, N. Vanlaethem-Meuree and J. Wisemberg Ultraviolet absorption cross-sections of chloro and chlorofluoro-methanes at stratospheric temperatures, ytr/nos. Chem. 7 (1988) 107-135. 

Some years ago Molina and Rowland (1974) demonstrated that chlorofluoro-methanes (see Section 3.3) are photochemically destroyed in the stratosphere by solar radiation with wavelength shorter than 0.23 pim to form chlorine atoms ... 

Increased ambient concentrations of organochlorine compounds, including chlorofluoro-methanes (freons), carbon tetrachloride, and chloroorganic compounds, constitute a great... 

Disproportionation reactions have been investigated extensively for chlorofluoro derivatives of methane.1 22,24... 

Sodium acid methanearsonate Methane base. See Bis (p-dimethylaminophenyl) methane Methane, bis (2-(2-butoxyethoxy) ethoxy)-. See Butylcarbitol formal Methanebis (N,N -(5-ureido-2,4-diketotetrahydroimidazole)-N,N-dimethylol). See Imidazolidinyl urea Methane, bromochloro-. See Bromochloromethane Methane, bromochlorodifluoro-. See Bromochlorodifluoroemethane Methane, bromodichloro-. See Bromodichloromethane Methane, bromotrifluoro. See Trifluorobromomethane Methanecarbonitrile. See Acetonitrile Methanecarboxamide. See Acetamide Methanecarboxylic acid. See Acetic acid Methane, chloro-. See Methyl chloride Methane, chlorodibromo-. See Chlorodibromomethane Methane, chlorofluoro-. See Chlorofluoromethane Methane, compressed. See Methane gas, Methane cyanine. See Malononitrile Methane, diazo-. See Diazomethane Methanedicarbonic acid Methanedicarboxylic acid. See,Malonic acid Methanedicarboxylic acid, diethyl ester. See Diethyl malonate... 

Greenhouse Gases Atmospheric gases that absorb infrared radiation the most important are carbon dioxide, methane, water vapor, and chlorofluoro-carbons. 

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