Skeleton notes on analytical chemistry : for students in medicine / by Albert J. Bernays.

  • Albert Bernays
Date:
1879
Catalogue details

Licence: Public Domain Mark

Credit: Skeleton notes on analytical chemistry : for students in medicine / by Albert J. Bernays. Source: Wellcome Collection.

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    HgjCrO^. KI yeUow-green Hg^I,. K^FeCy^ white mercurous feiTOcyanide. SnCU first a precipitate of mercurous cliloride aud theu of grey mercury. Thus: Hg._,C]2 + SnCl„ = Hg2 + SnCl4. Copper, zinc and iron, preci]iitate Hg. Mercury is usually estimated as Hg. Salts reduced in tube with Na/JOj. Heated on platinum, HggiNOg frrst wliite, yellow, red, black, and then volatilized. 4. Argentum oxide Ag^O grey-brown, soluble in NH3. (Chief salts: nitrate and sulphate. Neutral to test-paper.) HCl white, curd-like AgCl, insoluble in water, (soluble iu concen- trated HCl, in solution of NaCl, &c., but re-precipitated on addition of water,) soluble in NH3, and changing in color from white to violet on ex]30sure to light. HjS brown-black Ag,S, soluble in boiling HNO3. Na„C03 white Ag^COj, soluble in NH3 and salts. KOH grey-brown AgoO, soluble in NH3 and in HNO3. NH3, like KOH, but precipitate so soluble, that, in presence of free acid, there is no precipitate. KjCtoOj crimson Ag2Cr04. KI yellow Agl, insoluble in NHj aud in HNO3: iodide thus distinguished from a chloride. Potassium CYANIDE KCN white, curd-like AgCN, soluble in excess of precipitant. Cu, Fe, Hg, Zn, precipitate Ag. On charcoal, with NagCOj, or alone, reduced to white, lustrous bead, without incrustation: malleable. Silver is weighed as chloride, con- taining 75 .26 per cent, of silver, or as silver. Group II. HCl -|- H2S precipitates: A. as sulphides soluble in (NH4)2S2, yellow AS2S3 and pale-yellow SnS2; orange Sb2S3; brown SnS; black AujSg and PtS,: B. as sulphides, insoluble in (NH4)2S2, yellow CdS; deep-brown Bi^Sj; blue-black PbS; brown-black CuS ; black HgS and PdS. N.B.—A FERRIC SALT is reduced to a ferrous, and a salt of CHROMIC Acru to one of chromic oxide by H2S. A. Sulphides soluble in (NH4)2S2. Arsenicum as arsenious anhydride AS2O3, or as a soluble arsenite (Di-potassium hydrogen arsenite KjHAsOj, the common salt: strongly alkaline, colorless, no reaction with NaoCOa, and yellow precipitate with AgNOa, soluble in HNO3 and in NH3). In aikaline arsenites. HCl, in con- centrated solutions, a white precii^itate of AS2O3, soluble in excess. HCl + H.,S, bright-yellow AsoS,, soluble in NH3, in (NH,)2C03 and in (NHJ.S^o- CuSO,, green CuHAsOs, soluble in NH3. AgNOj, yellow AgsAsOj, soluble in NH3 and in HNO3. BaCL, white BaHAsOj, soluble in HCl. In solutions of arsenious acid. Litmus is reddened, yet
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