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
Catalogue details

Licence: Public Domain Mark

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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    arsenic. Two modifications: vitreous and crystnlline. The vitreous of sp. gr. 3.74, most soluble in water. The latter, at 100° onljr retains 11 per cent., and not more than 3 per cent, when cold. Very sululile in hot CIH. Poisonous: antiilotes magnesia and precipitated ferric hydroxide Fe^COHie. Crys- tallizes in octaliedra; rarely in prisms. Volatile without fu.siou at I 93°. 3 C. Its vajjor contains one vol. of As and 3 v<ds. of 0 condensed into 2 vols. Arsenites. Arsenious acid A.s(0H)3, is tri-basio and feebly acid. Frep. of AS2O3. By roasting arsenical ores : the As oxydizes and sublimes. PoTA.ssirai AHSENiTB As(0K)3, in Folder's solutiuu, u.sed in medicine. AuGENTUM ABSENITE A.sCOAgjj, is caiiary-yellow, soluble in H3N and in NOoOH. Cupeic hydkoxtl arsenite As(0H)(02Cu) or CuHAsOj, is Scheele's Green, toluble in H^N and in NO3H. 2. Arsenic anhydride As„Oj = 230. Arsenic pcMitoxide. White powder, somewhat deliquescent. Arsenic acid AsO(OH)3 or H3ASOJ, is a tribasic acid like orthophosphoric acid. The only well-defined hydrate answers to Pyr-arsenic acid As„03(OH)4. By oxydation of As^Oj by means of NO„OH, arsenic acid is obtained. Affords an easy method of preparing uitimis acid. AS2O3+ 3OH2+ 2NO„OH = 2AsO(OH)3+2NOOH. Arsenates. Many i^iomorphous with phospliates. Isomorphism ; similnriiy in form with analogy of composition. Silver arsenate AsO(OAg)3. liver-ljrown, soluble in H3N and in NO.^OH. CrPRic arsenate AsO(OH)(02Cu) is blue. As and S. a. Di-arsenicum disulphide ASjS., = 214 Eealgar jS'ative, in ruby-red prisms. Insoluble in water, and in CIH. Prepared artilicially 4AS2O3 -|- 78, = 4AS2S2 + 6yU2. White Indian fire is a mixture of 2 parts reidgar, 7 of sulphur and 24 of saltpetre, h. Arsenious sulphide ASjSj = 246. Orpiment: aurnm jiigmentum. Obliquo rhom- bio prisms of yellow color and brilliant lustre. Insoluble in water and in CIH. Very soluble in H3N, in ammonium car- bonate, and suljihide. Also in KOH. Thus: As.,S3-(-4KOH = OH„ -f- AsOHO >K)2 + AsSH(SK).^. Salts : Suipharsenites. c. Arsenic sulphide AsjS, = 310. Yellow substance, by fusion of S., wilh As„S.,. Not precipitated from acid solutions of arseihc acid by SIX.,. 2AsO(OH)3 + sSH, = 5OH2 -i- As.,S3 -|-S„ Sulpharseuates. [lu suipharsenites and sulpharsenates Sul- phur takes the place of Oxygen in the corresponding salts.] Sodium sulpharsenate AsS(SNa)3. End of the non-metallic elements. Eemarks. The reader will have observed that all the oxides of non- metallic compounds which arc called anhydrides, arc capable of