Elements of chemistry, in two volumes / by John Murray.

  • Murray, John.
Date:
1828
Catalogue details

Licence: Public Domain Mark

Credit: Elements of chemistry, in two volumes / by John Murray. Source: Wellcome Collection.

    81/768 (page 69)
    muM, is possessed of the following properties. It is so- lid, of a white colour, with metallic lustre, having a re- semblance to silver. It melts at a heat inferior to igni- tion, but is not volatilized even when heated to redness. Exposed to the air, it tarnishes rapidly, from absorbing oxygen, and falls into a white powder, which is barytes. Dropt into water, it immediately decomposes it, evolving hydrogen, and being converted into barytes. It sinks not only in water, but in sulphuric acid ; and Davy sup- posed it to be four or five times heavier than water. It is flattened by pressure strongly applied. Barium, it has been stated by Dr Clarke, may be obtained by exposing barytes mixed with oil to a kindled stream of oxygen and hydrogen. The combining weight of Barium has been determined to be 70 : united with one equivalent of oxy- gen, 8, it forms barytes, the combining weight of which is therefore 78. An oxide of barium may be formed, containing an ad- ditional atom of oxygen, by heating barytes to a low red heat, exposed to the air, or to oxygen gas; oxygen is ab- sorbed, and the barytes vitrifies at the surface, and be- comes of a greyish colour; this is the deutoxide or per- oxide of barium: it was employed by Thenard, as has been stated, in the formation of oxygenated water. Sulphuret of barium, procured by the methods of Ber- thier and Berzelius, is described as a light grey coloured mass, composed of crystalline grains loosely aggregated. When thrown into water it was completely dissolved forming a clear and colourless solution, being converted, it is inferred, into a hydro-sulphuret of barytes, the barium attracting oxygen from the water, and the sulphur uniting with the evolved hydrogen : accordingly, the addition of muriatic acid disengaged sulphuretted hydrogen. When heated with three or four times its weight of nitre, the