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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    a paint in priming. Prepared by carefully heating losvigated lead oxide in a reverberatory furnace at 5 20° C. Decomposed by NO,_.OH into lead nitrate and lead peroxide PbO„. 4. Plumbic peroxide PbO„ = 239. Native as heavy lead ore,'' in iron- black, lustrous, 6-sided prisms. Absorbs SO, and changed into SO„0.,Ph: test for S0„. Prep, of FhO„. 2PbO,Pb02+4N020H = 2[(N0„)..0.,Pb] -f PbO„ + 20H„. ' Also : (C„H30),0jPb + CO(ONa), + CI2 + 20H;= 2ClNa -1- 2(C„H30,OH) + OH^ -1- CO2 -I- Pbbo. Lead sulphide or plumbic sulphide SPb = 239, black. Precipitated in acid solutions by SH„. As galena it is found both massive, as in cubes and dodecahedra, of leaden hue, very lustrous and very brittle. Chief ore of lead. Metal- lurgy. SPb is first roasted. One portion remains unchanged SPb. Another portion oxydizes into lead sulphate SO„0„Pb, and yet another into SO, and lead oxide PbO. Now, when the furnace doors are shut, the lead sulphate and the lead oxide react upon the unchanged lead sulphide, and give lead with sulphurous anhydride. Thus: SPb -1- 2PbO = SO., + 3Pb. Again: SO^Pb + SPb = 280, -t- Pb„. Soluble salts' of PbO. Plumbum chloride CUPb, brilliant needles soluble in 135 parts of cold and 33 of boiling water. CIH precipitates soluble lead salts, when solution not too dilute. Nitrate (N02)oO,Pb, in white octahedra, soluble in 8 parts of cold water. Heated to red- ness into: PbO + 2NO, -|- O (p. 10). Acetai e (CJd30),0,Pb, 3OH2 is the sugar of lead of commerce. Eight rliombic prisms, soluble in 2 of water. Basic acetate contains 2PbO,OH2. Insoluble lead-salts. Oxy-cMoride 2PbO,Cl„Pb, native as Mendipite. Turner's Yellow yPbO.CLPb. * Chlorosulphide 3SPb,2Cl2Pb, is precipitated white by insutflcient SH„ from CljPb. Bromide BrjPb, white, sparingly soluble. Iodide IjPb, yellow, soluble in boiling water, separating on cooling in golden scale.s. Cyanide C,N„Pb, white. Sulphate SO .Pb = 303. W^hite. Native as ' lead vitriol in colorless prisms and octahedra. Soluble in sulphuric acid: contained in f)il of vitriol''and precipitated white by water. Chromate CrO.Fb yellow. Native as Lehmannite in oblique prisms. Di-plumbic chromate PbO,CiO|Pb is vermilion-colnred. Sulphite SOO„Pb, white. Carbonate COO.,Pb, native as Gerussite in needles. White lead (0H),Pb,2C002Pb. Dissolves in NO,OH as lead-nitrate. Water must be added to ascertain whether residue of SO,Ba. Silicate Si(0,Pb),. Flint-glass fiSiOj.K^OjPbO. Silicate and borate 3(Si002Pb),2B„03,3PbO. Paste or SlrasD for imi- tating gems 8Si02,K.,0,3PbO. Leafl-salts are poisonous. Antidote is Glauber salt, or Epsom salt, which precipitates SO.,Pb. Lead is weighed as lead sul- phate S04Pb containing 68.31 per cent, of metal.