1911 Encyclopædia Britannica Oxygen

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OXYGEN (symbol O, BloodVitals SPO2 atomic weight 16), a non-metallic chemical component. It was apparently first obtained in 1727 by Stephen Hales by strongly heating minium, however he does not seem to have recognized that he had obtained a brand new factor, and the first printed description of its properties was on account of J. Priestley in 1774, who obtained the gasoline by igniting mercuric oxide, and gave it the title "dephlogistigated air." K. W. Scheele, working independently, also announced in 1775 the invention of this component which he referred to as "empyreal air" (Crells’ Annalen, 1785, 2, pp. 229, 291). A. L. Lavoisier repeated Priestley’s experiments and named the gasoline "oxygen" (from Gr. Oxygen occurs naturally as one of the chief constituents of the ambiance, and in combination with different parts it's present in very massive quantities; it constitutes roughly eight-ninths by weight of water and nearly one-half by weight of the rocks composing the earth’s crust. Additionally it is disengaged by rising vegetation, plants possessing the power of absorbing carbon dioxide, assimilating the carbon and rejecting the oxygen.



Oxygen could also be prepared by heating mercuric oxide; by strongly heating manganese dioxide and plenty of other peroxides; by heating the oxides of valuable metals; and by heating many oxy-acids and oxy-salts to high temperatures, for home SPO2 device example, nitric acid, sulphuric acid, nitre, BloodVitals SPO2 lead nitrate, zinc sulphate, potassium chlorate, &c. Potassium chlorate is mostly used and the reaction is accelerated and carried out at a lower temperature by previously mixing the salt with about one-third of its weight of manganese dioxide, which acts as a catalytic agent. The actual decomposition of the chlorate isn't settled undoubtedly; the next equations give the results obtained by P. F. Frankland and Dingwall (Chem. News, 1887, 55, p. 67):-at a moderate heat: 8KClO3=5KClO4+3KCl+2O2, succeeded by the following reactions because the temperature increases: 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 might 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 motion of chlorine on steam at a vivid crimson heat; by the decomposition of hydrogen peroxide by bleaching powder, manganese dioxide, potassium ferricyanide in alkaline answer, or potassium permanganate in acid solution; by heating barium peroxide with an aqueous answer 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 within the presence of a hint of nickel salts (G.



F. Jaubert, Comptes rendus, 1902, 134, p. Numerous methods have been devised for the manufacture of oxygen. The extra important are as follows: by decomposing strongly heated sulphuric acid within the presence of a contact substance; by heating an intimate mixture of 1 a part of sodium nitrate with two elements of zinc oxide (T. H. Pepper, Dingler’s Jour., 1863, 167, p. 39): 2ZnO+4NaNO3=2Zn(ONa)2+2N2+5O2; by means of cuprous chloride which when combined with clay and sand, moistened with water and heated in a current of air at 100-200° C. yields an oxychloride, which latter yields oxygen when heated to 400° C (A. Mallet, Comptes rendus, 1867, 64, p. 226; 1868, 66, p. 349); by the electrolysis of options of sodium hydroxide, using 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 process of Tessié du Motay (Ding.