Practical chemistry / by Stevenson MacAdam.

  • MacAdam, Stevenson.
Date:
[1865]
Catalogue details

Licence: Public Domain Mark

Credit: Practical chemistry / by Stevenson MacAdam. Source: Wellcome Collection.

    169/180 (page 153)
    Solution of Substances. 297. The substance is neither a Metal nor an Alloy. Treat the substance with water and acids as directed at pars. 233—237. Tlie substance is insoluble in water and in acids, ia.) Yellow, and burns with odour of SOq, = ScLPHUR. {h.) Black, burns on platinum vessel, and deflagrates with KOjNOs, = Charcoal. (c.) Add NH4S,HS to a small quantity of the substance under examination. / The substance becomes black. ■ “ 'i The substance remains white. 1. If fused when heated in glass tube, may indicate PbCl, PbBr, AgCl, AgBr, or Agl. Mix -with 4 parts of white flux, and fuse in porcelain capsule before the blow-pipe. When cold, add water, boil, filter, and test the liquid for HCl, HBr, or HI (pars. 222—224). The residue is either the metal Ag or Pb, Digest in HO5, and test the solution (pars. 204—209). 2. Cy was evolved from glass tube, and metallic Ag remains, = AgCy. 3. T^e substance did not change when heated in glass tube, = Pb0,S0.3. Add solution of Xa0,C02, and boil, filter. Filtrate. Test for SO3 (par. 221). Contents of filter. Dissolve in NO5, and test for Lead (pars. 204, 205, and 210). 1. Mix a portion with fine sand and H0,S03 ; heat in plat- inum capsule. Irritating fumes are evolved, which are acid to test papers, and corrode glass; indica- tive of HF from CaF. Treat the residue with HCl, boil, filter; add HH4O; filter again if necessary, and test for lime. 2. No fumes are evolved. Mix with 4 times its weight of white flux, and fuse on platinum before blow-pipe. When cold, add water, boil, filter. / Filtrate. Add HCl and BaCl for Sulphuric Acid. If no SO3, then evapo- rate, and retreat with water, and insoluble flakes de- note Silica or SiLi- Contents of filter. If SO3 has been de- tected, the metallic oxide is on the filter. Add —HCl; filter again, and test the liquid for BaO, SrO, or CaO. CATES. 298. The substance is a metal or an alloy. Proceed as at pars. 243—245.