Notes on analytical chemistry : for students in medicine / by Albert J. Bernays.
- Albert Bernays
- Date:
- 1886
Licence: Public Domain Mark
Credit: Notes on analytical chemistry : for students in medicine / by Albert J. Bernays. Source: Wellcome Collection.
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![Aluminum phosphate, AlPO^, is white, unchangeable. The Bolutiou in HCl iiives phosphate reaction with acid molybdate (p. 41), and on platinum, when ignited with cobalt nitrate, Thenard's blue (p. 26). Insoluble in acetic acid. Barium, strontium, calcium and magnesium phos- phates dissolve in HCl with ease; also in acetic acid. Unchanged by heat. Moistened with HCl and heated, Ba gives yellowish- green color to flame, Sr crimson, Ca yellowish-red, Mg no reaction. To remove the phosphate so as to obtain only chlorides of the respective metals in solution, add to the HCl solution acetate of sodium, then ferric chloride till a distinct red color appears in the supernatant fluid: ferric phosphate, FePO^, is thrown down. Boil, filter, precipitate by ammonia any ferric in solution, filter, and examine the filtrate'for Ba, Sr, Ca, and Mg. The phosphate will be discovered by the acid molybdate in the HCl solution (p. 41). Calcium oxalate, CaG^Oi, white. Heated on platintun, be- comes grey in color, and is converted into carbonate, insoluble in water, alkaline from presence of some calcium oxide, sohible, with effervescence, in HCl, and only gives reactions of calcium (p. 31). Boiled with sodium carbonate, sodium oxalate is found in solution (p. 45). Carbonates of barium, strontium, calcium, and mag- nesium are white and infusible. Moistened with HCl, effer- vescence, and on re-heating the characteristic colors of Ba, Sr and Ca to flame, as just given. [Cream of tartar, or hydro-tartrate of potassium, KHC^H^Oe, is often passed over as insoluble. Effervescence from H2S when sulphide of ammonium added. On platinum, violet color to flame, smell of burnt sugar as the tartaric acid is decom- posed, and carbon which burns away, leaving fused carbonate of potassium. The latter dissolves in little water, is alkaline, effervesces with HCl, and yellow pr. with 2HCl,PtCl4. Very soluble in HCl. Also in KOH, and, on careful addition of HCl, white, crystalline pr. of cream of tartar (p. 68).] b. The white substance does not dissolve. When hydrochloric or nitric acid have failed in effecting solution, it is as well to look at once for several common white powders. Barium sulphate, BaSO^, white, insoluble. Moistened with HCl on platinum, it gives yellowish green flame of barium. On charcoal, heated with NaaCOg, the mass boiled with water and filtered, the insoluble part can be tested after solution in HCl for Ba (p. 30), and the soluble, containing sulphide and sulphate, indicates the former by blackening silver-coin on which laid, by the smell of H^S, &c. Strontium sulphate, SrS04, requires same treatment as BaSOj, but is sufiiciently soluble in HCl to give a reaction with CaS04 (p. 31), and the crimson color to flame. Calcium sulphate, CaSOi, is sufficiently soluble in water to](https://iiif.wellcomecollection.org/image/b21499056_0124.jp2/full/800%2C/0/default.jpg)
