1. groupChemistry, See also 官能基
2. (free) radicalSee also 遊離基
3. counter for installed or mounted objects (e.g. stone lanterns, gravestones, satellites)
Wikipedia definition
4. Functional groupIn organic chemistry, functional groups are lexicon specific groups of atoms or bonds within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reaction(s) regardless of the size of the molecule it is a part of. However, its relative reactivity can be modified by nearby functional groups.
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Read “Functional group” on DBpedia


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