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.

    68/768 (page 56)
    it dissolves abundantly in water : its solution is colourless, but gives a green tinge to paper: it has a smell of sul- phuretted hydrogen. Acids produce with it a brisk ef- fervescence, and render this odour very strong; but they do not render the liquid turbid. Nitrous acid and chlo- rine, however, produce a precipitate of sulphur. Carbonate of Soda. This salt is extracted from ba- rilla by lixiviating it with warm water, and evaporating the solution, so that in cooling it shall crystallize: the salt is alkaline, its taste is acrid, and it changes the vegetable colours to a green. The crystals are octohedrons; they ai'e efflorescent; they require twice their weight of water at 60° for solution. Exposed to heat, they suffer the wa- tery fusion from the action of the water of crystallization they contain: as this is dissipated, the salt appears as a dry white powder, which by an increase of heat may be fused. The real salt, it is inferred, consists of one atom of acid, and one of soda ; but it always contains a large quan- tity of water, calculated even to amount in general to 10 atoms. Bi-carbonate of Soda may be obtained, by trans- mitting carbonic acid gas through a solution of the car- bonate : by evaporation it is then obtained in crystals. Containing twice as much carbonic acid as the other, Dr Wollaston gave it its present name. The anhydrous salt consists of two atoms of carbonic acid and one of soda, and contains, in general, also, according to Dr Thomson, an atom of water. The native carbonate of soda, found in Africa, and called Trona, consists, according to Mr R. Phillips, of one equivalent of soda, and one and a half of carbonic aoid, or it is a sesqui-carbonate of soda. Nitrate of Soda crystallizes in prisms. Its taste is cool; it slightly attracts moisture from the air ; is soluble in 3 parts of water at 60°, and in an equal weight of boil-