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1 個解答

  • 1 十年前

    1. H3C-S-CH3 應該係


    Iodomethane, commonly called methyl iodide and commonly abbreviated "MeI", is the chemical compound with the formula CH3I. This dense volatile liquid is related to methane by replacement of one hydrogen atom by an atom of iodine and its dipole moment is 1.59 D. Refractive index is 1.5304 (20 °C, D), 1.5293 (21 °C, D). It is miscible with common organic solvents. It is colourless, although upon exposure to light, samples develop a purplish tinge caused by the presence of I2. Storage over copper metal absorbs the iodine. Methyl iodide is widely used in organic synthesis to deliver a methyl group, via the transformation called methylation. It is naturally emitted by rice plantations in small amounts.

    2. 係, 因為fluoromethane係一氟甲烷, 又名methyl fluoride, 即係氟化甲基


    Fluoromethane, also known as methyl fluoride, Freon 41, Halocarbon-41 and HFC-41, is a non-toxic, liquefiable, and flammable gas at standard temperature and pressure. It is used in the manufacture of semiconductor and electronic products. In the presence of an RF field fluoromethane will dissociate into fluoride ions that selectively etch silicon compound films.

    Bond energy of C-F is 552 kJ/mol and its length is 0.139 nm (typically 0.14 nm).

    Its specific heat capacity is Cp = 38.171 J.mol-1.K-1 at 25 °C. Critical point of fluoromethane is at 44.9 °C (318.1 K) and 6.280 MPa. Its global warming potential is GWP = 150.

    資料來源: 維基