Methyl

[ I ] This refers to the _CH3- group. It is the simplest alkyl group and is sometimes abbreviated as Me-. [ II ] This refers to the methyl radical. It can be produced by the photolysis of acetone or the thermal decomposition of methane. A methyl radical forms a flat equilateral triangle, and its C-H bond is 0.108 nm long. It is highly reactive, and will abstract an H from compounds that contain H to form methane. Methyl radicals can also recombine with each other to form ethane.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

【Ⅰ】CH₃-基をいう．もっとも簡単なアルキル基で，Me-と略されることもある．【Ⅱ】メチルラジカルをいう．アセトンの光分解やメタンの熱分解でつくることができる．メチルラジカルは正三角形の平面をなし，C-H結合の長さは0.108 nm である．非常に反応性が高く，Hを含む化合物からHを引き抜いてメタンになる．また，メチルラジカルどうしは再結合してエタンになる．

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