Any of a group of five chemically related nonmetallic elements including fluorine, chlorine, bromine, iodine, and astatine.
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Of or relating to the group of elements that are halogens.
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Of or relating to a bright incandescent light bulb containing a halogen gas that prevents the filament from disintegrating at higher temperatures.
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Any of the five very reactive, nonmetallic chemical elements making up group VIIA of the periodic table: fluorine is the lightest and most reactive of the group, and astatine is the heaviest and least reactive.
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Any of a group of five nonmetallic elements with similar properties. The halogens are fluorine, chlorine, bromine, iodine, and astatine. Because they are missing an electron from their outermost shell, they react readily with most metals to form salts.
From Ancient Greek ἅλς (hals, “salt”) + -gen (“produce”), referring to elements which produce a salt in union with a metal.
Sentence Examples
This change only occurs when the halogen atom is in the orthoor paraposition to the - N2 - group.
It is decomposed by the halogen elements and also by sulphuretted hydrogen.
It is to be noted that only traces of the aromatic amines are produced by heating the halogen substituted benzenes with ammonia, unless the amino group be situated in the side chain, as in the case of benzylamine.
Molybdenum combines with the halogen elements in varying proportions, forming with chlorine a di-, tri-, tetraand penta-chloride, and similar compounds with bromine and iodine.
Similarly, the formation of organic halogen products may be effected by electrolytic chlorine, as, for example, in the production of chloral by the gradual introduction of alcohol into an anode cell in which the electrolyte is a strong solution of potassium chloride.