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CHLORATES
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CHLORATES , the metallic salts of chloric See also:acid; they are all solids, soluble in See also:water, the least soluble being the See also:potassium See also:salt. They may be prepared by dissolving or suspending a metallic See also:oxide or hydroxide in water and saturating the See also:solution with See also:chlorine; by See also:double decomposition; or by neutralizing a solution of chloric acid by a metallic oxide, hydroxide or carbonate. They are all decomposed on See also:heating, with See also:evolution of See also:oxygen; and in contact with concentrated sulphuric acid with liberation of chlorine peroxide. The most important is potassium chlorate, KCIO3, which was obtained in 1786 by C. L. Berthollet by the See also:action of chlorine on See also:caustic potash, and this method was at first used for its manufacture. The See also:modern See also:process consists in the See also:electrolysis of a hot solution of potassium chloride, or, preferably, the formation of See also:sodium chlorate by the electrolytic method and its subsequent decomposition by potassium chloride. (See See also:ALKALI MANUFACTURE.) Potassium chlorate crystallizes in large See also: Chem. See also:Soc., 1886, p. 141), the decomposition of potassium chlorate by See also:heat is not at all See also:simple, the quantities of chloride and perchlorate produced depending on the temperature. A very See also:gentle heating gives decomposition approximating to the See also:equation of 22KC103=14KC104+8KC1+502, whilst on a more rapid heating the quantities correspond more nearly to 10KC1Os=UKCIO4+4KCI+302. The decomposition is renderedmore easy and See also:regular by mixing the salt with powdered See also:manganese dioxide. The salt finds application in the preparation of oxygen, in the manufacture of matches, for pyrotechnic purposes, and in See also:medicine. Sodium chlorate, NaClOa, is prepared by the electrolytic process; by passing chlorine into See also:milk of See also:lime and decomposing the See also:calcium chlorate formed by sodium sulphate; or by the action of chlorine on sodium carbonate at See also:low temperature (not above 35° C.). It is much more soluble in water than the potassium salt. Potassium chlorate is very valuable in medicine. Given in large doses it causes rapid and characteristic poisoning, with alterations in the See also:blood and rapid degeneration of nearly all the See also:internal See also:organs; but in small doses—5 to 15 grains—it partly undergoes reduction in the blood and tissues, the chloride being formed and oxygen being supplied to the See also:body-cells in nascent See also:form. Its See also:special uses are in ulceration of the mouth or See also:tongue (ulcerative stomatitis), See also:tonsillitis and See also:pharyngitis. For these conditions it is administered in the form of a See also:lozenge, but may also be swallowed in solution, as it is excreted by the saliva and so reaches the diseased See also:surface. Its remarkable efficacy in healing ulcers of the mouth—for which it is the specific—has been ascribed to a decomposition effected by the carbonic acid which is given off from these ulcers. This releases chloric acid, which, being an extremely powerful antiseptic, kills the bacteria to which the ulcers are due. Additional information and CommentsThere are no comments yet for this article.
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