Halogen

A halogen is an element from group 17 of the periodic table, that is, one of fluorine, chlorine, bromine, iodine or astatine. The name is derived from the Ancient Greek ἅλς (hals, genitive ἁλός halos, "salt") and -γενής (genēs, "producer of"), and was first used in 1811 by the German chemist J. S. C. Schweigger (1779–1857) to refer to chlorine, the only element that was known at that time to react directly with metals to produce salts.{{#tag:ref|It is often stated that the term "halogen" was coined by Swedish chemist Jöns Jacob Berzelius (1779–1848): this misconception seems to arise from the first English use of the word, which was in a translation of one of Berzelius' papers in the Proceedings of the American Philosophical Society (1832, 2, 219).</ref>Halogen. In A New English Dictionary on Historical Principles; Oxford University Press, 1901; Vol. 5, p 44</ref><ref>Greenwood, Norman N.; Earnshaw, A. Chemistry of the Elements; Pergamon: Oxford, 1984; pp 920–21. ISBN 0-08-022057-6.<ref>