Notes for students in chemistry : being a syllabus of chemistry compiled mainly from the manuals of Fownes-Watts, Miller, Wurz, and Schorlemmer / by Albert James Bernays.

Albert Bernays

Date:: 1878

Credit: Notes for students in chemistry : being a syllabus of chemistry compiled mainly from the manuals of Fownes-Watts, Miller, Wurz, and Schorlemmer / by Albert James Bernays. Source: Wellcome Collection.

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$soluble in etlier, but more so in benzene, turpentine and other oils. In CS,,, in S^CU and in PCI, it is freely soluble and may be obtained crystallized in i-hombic dodecaliedra. It is a non- conductor of electricity. When slowly oxydized, it gives rise to PHOsPHOEODS ANHYDRIDE P0O3: in activc, full combustion, to PHOSPHORio ANHYDRIDE If One volume of H encloses one atom, one volume of phosphorus in vapor encloses two atoms : the molecules, of two volumes, Iherefore, four atoms. 11.19 litres weigli 62 grammes. Phosphorus affords one of the most interesting illustrations of allotropism.—If common or vitreous phosphorus be exposed to light under water, it becomes wMte, opake, less fusible and of sp. gr. 1.515 ; it is re-converted into the vitreous at a temperature below 50° C.—A third variety is obtained by suddenly cooling melted phosphorus. This is black and npuke, but becomes vitreous by simple fusion and slow cooling.—A fourth, or viscous variety, by lieatiug very pure phosphorus to near its boiling-point and suddenly cooling.—The tilth is the most important variety, as it is not poi.sonous, and need not be kept under water, as it does not inflame below 260° C. First obtained by sublimation of Phosphorus iu the Torricellian vacuum by exposure to sunlight. It is now largely prepared by lieating vitreous phosphorus in an atmosphere of carbonic anhydride for 30 or 40 hours at a temperature of 230X. to 240° C. A red powder of sp. gr. 2.14. Insoluble in all media. Crystallizes in rhombohedra. At 260° C. inflames and burns to PoOj. In CU it burns, as does the vitreous, and it detonates when rubbed with ClOjOK. Used in Bryant and May's, and Bell and Black's matches. Prep, of commoii phosphorus. Cal- CHiM ortho-phosphate (POJ.,Ca, is changed by S()^H„ into Calcium svperphosfhate [(Pd.,)„H,Ca] and Calcium sulphate SO.Ca. Thus : (P0,)..Ca3 -f 2Sb,H, = 2S0,Ca + (PO,)„H,Ca. The superphosphate is filtered off from the nearly msoluble SOjCa, is mixed with charcoal, dried, and heated to rechiess. TJie superphosphate (PCi^JIjCa by loss of 2OH., becomes CALCIUM metaphosphate (P03).,Ca. And tlds metaphosphate heated to whiteness in an earthen retort with charcoal, gives calcium pyrophosphate, carbon oxide and Phosphorus, Thus: 4['P03\Ca]-f ioO=2[P.,0;Ca„]4-ioCO-|-P4. The phosphorus is received in water. Compounds. P witli H. Three compounds H3P; H,P„ and H.P^, a gas, a liquid, and a solid, a. Phos- phorus hydride or Phosphiue H3P =34- Colorless gas of strong garlic od(a-. Very inflammabic, burning into water and phos- phoric anhydi-ide. 4 \o\s. require 8 vols, of O for complete combustion. Very little soluble in water. Behaves like am- monia and unites witli IH to iodide of phosphonium H^PI. J'rep. a. distilling phosphorous acid PHO^OII).. Tlius: 4PH0(OII)., = 3PO(OII)3 + K^T.—h. boiling phosphorus with$