[a. mod.L. ammonia, invented by Bergman, in 1782, as a name for the gas obtained from Sal-ammoniac: see next.]
1. A colorless gas with pungent smell and strong alkaline reaction, chemically a compound of three equivalents of hydrogen with one of nitrogen, NHc, which at a pressure of 61/2 atmospheres, at 50° Fahr., is condensed to a colorless liquid. Called also Spirit of Hartshorn, in allusion to one of its early sources, the dry distillation of nitrogenous matter, as the hoofs and horns of animals; and Volatile or Animal Alkali, in contradistinction to the ‘fixed’ alkalis, potash or ‘vegetable’ alkali, and soda or ‘mineral’ alkali.
1799. A. Aikin, Syllabus Lect. Chem., 7. Ammonia, or Volatile Alkali.
1801. Hatchett, in Phil. Trans., XCII. 50. Ammonia formed a yellow flocculent precipitate.
1810. Dalton, Syst. Chem. Philos., II. v. § 6. 415–6. It has been long known to chemists as an important element, and under various names,… namely, volatile alkali, hartshorn, spirit of sal ammoniac, &c., but authors at present generally distinguish it by the name of ammonia.
1822. J. Flint, Lett. fr. Amer., 62. A chemical manufactory in which ammonia, copperas … and various acids, are prepared.
1855. Bain, Senses & Int., II. ii. § 1. In smelling salts, ammonia is the substance given forth.
2. pop. Ammonia, or specifically Liquid Ammonia: a solution of ammonia in water, being the form in which it is commercially used.
c. 1850. J. Griffin, in Ure, Dict. Arts, I. 140. To judge at a glance of the money value of any given sample of ammonia.
1863. Watts, Dict. Chem. (1872), I. 184. Solution of ammonia, Aqueous ammonia, or simply Ammonia, Spirits of hartshorn.
3. Chem. Extended to a large series of compounds, analogous to ammonia, in which one or more of the three hydrogen atoms of NH3 are replaced by a basic metal or radical (AMINES), or by the oxygenized radical of an acid (AMIDES), or by both at once (ALKALAMIDES).
1863. Watts, Dict. Chem. (1872), I. 169. Ammonias in which 1 or more atoms of hydrogen are replaced by an acid-radicle.
1869. Roscoe, Elem. Chem., xxix. 312. Each alcohol also forms a series of compound ammonias.
4. Comb. in which ammonia stands chiefly in attrib. relation, as ammonia gas, compounds, process, solution, substitution compound, works, etc. Also ammonia alum, amalgam, carbonate, salts, etc., in which AMMONIUM is now used in more systematic nomenclature.
