. An analytical compendium of the various branches of medical science, for the use and examination of students. Anatomy; Physiology; Surgery; Obstetrics; Medicine; Materia Medica. HYDROGEN NITROGEN. ^5 heat thus produced is sufficient to melt the most refractory metals.— Symb. H;—Eq. 1. Hydrogen forms two compounds with oxygen: water, or the protoxide, and the peroxide. Water, HO,—first proved to be composed of hydrogen and oxygen, by Cavendish; this may be shown synthetically, by mixing one volume of oxygen with two of hydrogen, and exploding the mixture, when water will be the sole product,—
. An analytical compendium of the various branches of medical science, for the use and examination of students. Anatomy; Physiology; Surgery; Obstetrics; Medicine; Materia Medica. HYDROGEN NITROGEN. ^5 heat thus produced is sufficient to melt the most refractory metals.— Symb. H;—Eq. 1. Hydrogen forms two compounds with oxygen: water, or the protoxide, and the peroxide. Water, HO,—first proved to be composed of hydrogen and oxygen, by Cavendish; this may be shown synthetically, by mixing one volume of oxygen with two of hydrogen, and exploding the mixture, when water will be the sole product,—or, analytically, by decom- posing water either by red hot iron, or by galvanism; in the last case, a small portion of water is interposed between a pair of platinum plates, connected with the ex- ^^* ' tremities of a voltaic apparatus of moderate power; pure oxygen gas is evolved at the positive plate, (or that connected with the copper end,) and pure hydrogen at the negative, or zinc extremity; the gases may be properly collected and measured. The composition of water is, by weight, 8 parts of oxygen, and 1 of hydrogen; by volume, 1 vo- lume of oxygen, and 2 of hydrogen. Prop.—Colourless, inodorous, tasteless; power- ful refractor of light; imperfect conductor of heat and electricity ; very incompressible ; sp. gr. 1. It does not occur, in nature, chemically pure;—can only be procured pure by distillation. Water acts powerfully as a chemical agent, forming compounds termed hydrates; sometimes the reaction is accompanied with the evolution of heat, as in the slaking of lime. Water also enters into the composition of many crystals, constituting their water of crystallization ; its solvent pro- perties are pre-eminent. Water in its natural state al\7ays contains atmospheric air, as may be shown by placing it under a receiver and exhausting the air ; bubbles of gas will make their escape. Re- cently boiled water has the property of absorbing gases, though in different
Size: 1047px × 2385px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., booksubjectmateriamedica, booksubjectmedi, booksubjectphysiology
