Manual of qualitative analysis / by Robert Galloway.

  • Galloway, Robert.
Date:
1861
Catalogue details

Licence: Public Domain Mark

Credit: Manual of qualitative analysis / by Robert Galloway. Source: Wellcome Collection.

    64/272 (page 46)
    taken not to touch, even with the fingers, that end’of it on which the substance is to be placed. SPECIAL REMARKS. 104. AmmMont1a.—This substance is a gas, transparent and colourless, of a very pungent and peculiar smell and taste. It is instantly absorbed by water, forming the solution of the gas called aqua ammonia. If this liquid is boiled, the gas is expelled. When organic substances con- taining nitrogen decay and putrefy, carbonate of ammonia is constantly produced. The same salt is likewise formed when nitrogenized organic substances are submitted to de- structive distillation. 105. When any volatile acid is brought into an atmo- sphere of ammonia, they unite together, forming a solid salt; this is the white fumes observed in testing for ammonia. 106. Ammonia may be liberated from its combinations, and the most securely detected, in the following way :—the substance supposed to contain the ammoniacal salt, either in the solid state or dissolved, is mixed with an excess of hydrate of lime in a small beaker, and, if necessary, a little water ; if the substance supposed to contain ammoniacal salt is in a state of solution, sufficient hydrate of lime must be added to the portion of the solution examined for ammonia to render it perfectly dry and solid. The beaker is covered, after the mixing, with a glass plate, on the lower side of which adheres a small piece of moist turmeric or moist red- dened litmus paper. 107. Bichloride of platinwm (PtCl,) produces in neutral and acid solutions of ammonia a yellow crystalline pre- cipitate, which is a double salt of CHLORIDE OF AMMONIUM and CHLORIDE OF PLATINUM (NH,Cl, PtCl,).