1911 Encyclopædia Britannica/Oxygen > 자유게시판

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OXYGEN (image O, BloodVitals tracker atomic weight 16), a non-metallic chemical factor. It was apparently first obtained in 1727 by Stephen Hales by strongly heating minium, however he does not appear to have recognized that he had obtained a brand new ingredient, and the first published description of its properties was as a result of J. Priestley in 1774, who obtained the gasoline by igniting mercuric oxide, and gave it the name "dephlogistigated air." K. W. Scheele, working independently, additionally introduced in 1775 the discovery of this element which he known as "empyreal air" (Crells’ Annalen, 1785, 2, pp. 229, home SPO2 device 291). A. L. Lavoisier repeated Priestley’s experiments and named the gas "oxygen" (from Gr. Oxygen happens naturally as one of the chief constituents of the ambiance, and together with different elements it is present in very giant quantities; it constitutes approximately eight-ninths by weight of water and practically one-half by weight of the rocks composing the earth’s crust. It is also disengaged by rising vegetation, plants possessing the power of absorbing carbon dioxide, assimilating the carbon and rejecting the oxygen.

Oxygen may be ready by heating mercuric oxide; by strongly heating manganese dioxide and many different peroxides; by heating the oxides of precious metals; and by heating many oxy-acids and oxy-salts to excessive temperatures, for example, nitric acid, sulphuric acid, nitre, lead nitrate, zinc sulphate, potassium chlorate, BloodVitals SPO2 device &c. Potassium chlorate is generally used and the response is accelerated and carried out at a lower temperature by beforehand mixing the salt with about one-third of its weight of manganese dioxide, which acts as a catalytic agent. The precise decomposition of the chlorate will not be settled positively; the next equations give the outcomes obtained by P. F. Frankland and Dingwall (Chem. News, 1887, 55, p. 67):-at a average heat: 8KClO3＝5KClO4＋3KCl＋2O2, succeeded by the next reactions because the temperature will increase: 2KClO3＝KClO4＋KCl＋O2 and 2KClO3＝2KCl＋3O2 (see additionally F. Teed, ibid., 1887, 55, p. 91; H. N. Warren, ibid., 1888, 58, p. 247; W. H. Sodeau, Proc. Chem Soc., 1901, 17, p.

149). It could also be obtained by heating manganese dioxide or potassium bichromate or potassium permanganate with sulphuric acid; by the action of cobalt salts or manganese dioxide on a solution of bleaching powder (Th. Fleitmann, Ann., 1865, 134, p. 64); by the motion of a ferrous or manganous salt with a salt of cobalt, nickel or copper on bleaching powder (G. F. Jaubert, Ger. pat. 157171); by passing chlorine into milk of lime (C. Winkler, Jour, prakt. Chem., 1866, 98, p. 340); by the action of chlorine on steam at a shiny red heat; by the decomposition of hydrogen peroxide by bleaching powder, manganese dioxide, potassium ferricyanide in alkaline resolution, or potassium permanganate in acid solution; by heating barium peroxide with an aqueous solution of potassium ferricyanide (G. Kassner, Zeit. angew. Chem., 1890, p. 2＋O2; by the decomposition of sodium and potassium peroxides with an answer of potassium permanganate in the presence of a trace of nickel salts (G.

F. Jaubert, Comptes rendus, 1902, 134, p. Numerous methods have been devised for the manufacture of oxygen. The more vital are as follows: by decomposing strongly heated sulphuric acid within the presence of a contact substance; by heating an intimate mixture of 1 part of sodium nitrate with two parts of zinc oxide (T. H. Pepper, Dingler’s Jour., 1863, BloodVitals test 167, p. 39): BloodVitals tracker 2ZnO＋4NaNO3＝2Zn(ONa)2＋2N2＋5O2; by the use of cuprous chloride which when blended with clay and sand, moistened with water and BloodVitals SPO2 heated in a present of air at 100-200° C. yields an oxychloride, which latter yields oxygen when heated to 400° C (A. Mallet, Comptes rendus, BloodVitals tracker 1867, 64, p. 226; 1868, 66, p. 349); by the electrolysis of options of sodium hydroxide, utilizing nickel electrodes; by heating calcium plumbate (obtained from litharge and calcium carbonate) in a present of carbon dioxide (G. Kassner, Monit. Scient., 1890, pp. 503, 614); and from air by the means of Tessié du Motay (Ding.