Inorganic chemistry / by the late George Wilson ... revised and enl. by H.G. Madan.

  • George Wilson
Date:
1872
Catalogue details

Licence: Public Domain Mark

Credit: Inorganic chemistry / by the late George Wilson ... revised and enl. by H.G. Madan. Source: Wellcome Collection.

    499/550 (page 481)
    siphon, and forces the liquid past the zinc into the longer tube. In this way evolution of gas ceases, when the liquid and zinc are separated from each other. When the stop-cock is opened, the liquid returns from the long limb, and reproduces gas, forcing out what had accumulated. 1177. Both Marsh’s and Reinsch’s tests are often applied for the detection of arsenic in cases of poisoning. It is, of course, absolutely essential that the materials should be previously proved to be pure, since common copper, zinc, and hydric sulphate often contain arsenic. The liquid to which Marsh’s test is to be applied should not contain organic matter. This may be got rid of by heating it for some time with a solution of potassic chlorate and a little hydric nitrate; or, as Dr Odling suggested, by adding an excess of hydric chloride, and dis- tilling nearly to dryness. The distillate contains the arsenic as chloride. ANTIMONY. Symbol. Weight. I Atom Sb 122 ] Density =6-7. xi78. Antimony was discovered in the fifteenth century, but one of its compounds, the sulphide, had been known for a long period, and was, and still is, employed in the East as a pigment for darkening the eyebrows. This native sulphide, which is the mineral ‘ antimonite,’ is very abundant in Hungary, Saxony, and other places, and is the chief ore of the metal, although the latter also occurs in combination with arsenic and silver, some- times as a native alloy, sometimes as a double sulphide. The symbol for its atom, Sb, is derived from the Latin stibium, which is the old name of the pigment above alluded to, formed from antimonious sulphide. 1179. In order to obtain the metal, the sulphide is „first roasted at a temperature insufficient to melt it, until the sulphur is driven off, and an impure oxide remains. This is mixed with charcoal and sodic carbonate, and fused at a low red heat in a crucible, when the metal is reduced and sinks to the bottom in 2 E