NHi4 = 18.

There is no metallic ammonium (L. Ammoni-a + um, fr. (sal) ammoniac, obtained from near temple of Jupiter Ammon, in Libya, by burning camel's dung); the nearest approach to it, so far, being the ammonium amalgam or alloy made by dissolving potassium in mercury, and adding a strong solution of ammonium chloride, when potassium chloride and ammonium amalgam are formed, this latter being a soft spongy metallic substance readily decomposing into mercury, hydrogen, and ammonia gas. Although we have not the metal as represented in these elements thus joined, we nevertheless have many salts consisting of NH4 in combination with various acids, all of which by physical and chemical properties resemble those of potassium, sodium, and lithium.

Tests for Ammonium Salts: 1. All compounds evolve ammonia gas when heated with calcium, potassium, or sodium hydroxide; the gas is recognized by odor, by restoring reddened litmus-paper, by dark-blue with cupric sulphate paper. 2. With platinic chloride + HC1 get yellow precipitate. 3. Salts are white, volatile, and soluble in water. 4. In neutral solutions cobaltic nitrite gives yellow precipitate.

Ammonii Benzoas. Ammonium Benzoate, NH4C7H5O2. - (Syn., Amnion. Benz., Ammonium Benzoicum. Ammoniae Benzoas, Benzoas Ammonicus; Fr. Benzoate d'Ammoniaque; Ger. Benzoesaures Amnion.)

Manufacture: Dissolve benzoic acid in 20 p. c. ammonia water by warming, stirring, keeping solution always alkaline, set aside to crvstal-lize - NH4OH + HC7H5O2 = NH4C7H5O2 + H2O. It is in thin, white, laminar crystals or crystalline powder, odorless or slight odor of benzoic acid, saline, bitter, acrid taste; loses ammonia on exposure, soluble in water (10), alcohol (35.5), glycerin (8); heated evolves ammonia and benzoic acid; ash .05 p. c.; aqueous solution neutral or slightly acid. Tests: 1. Aqueous solution (1 in 10) + ferric chloride T. S. - pink precipitate. 2. Heated with potassium hydroxide T. S. - evolves ammonia; contains 98 p. c. of the pure salt. Impurities: Heavy metals, etc. Should be kept cool in well-closed containers. Dose, gr. 5-30 (.3-2 Gm.), best given in mixture.

Properties and Uses. - Stimulant, diuretic, alterative. Due to the benzoic acid, which is absorbed and eliminated by the kidneys as hippuric acid - the ammonia base as nitric acid; for defective action, solvent for phosphatic deposits (phosphaturia), cystitis, gouty affections, uric acid gravel, muscular rheumatism.

Incompatibles: Acids, ferric salts, solution potassium hydroxide.

Ammonii Bromidum. Ammonium Bromide, NH4Br. - (Syn., Ammon. Brom.; Fr. Bromure d'Ammonium; Ger. Ammonium bro-matum, Ammoniumbromid, Bromammonium.)

Manufacture: 1, Neutralize hydrobromic acid with ammonia water or carbonate, evaporate, crvstallize - HBr + NH4OH = NH4Br + H2O; 2, 2NH4OH + FeBr2 = 2NH4Br + Fe(OH)2; 3, (NH4)2SO4 + 2KBr = 2NH4Br + K2SO4; this last method is the best. It is in colorless, transparent, prismatic crystals, white, crystalline or granular powder; odorless, pungent saline taste; somewhat hygroscopic, soluble in water (1.3), boiling water (.9), alcohol (12), boiling alcohol (1.2); heated volatilizes without fusing. Tests: 1. Aqueous solution, neutral or slightly acid, heated with potassium hydroxide T. S. - evolves ammonia. 2. With silver nitrate T. S. - yellowish-white precipitate, insoluble in nitric acid, or moderate excess of ammonia water. 3, Incinerate - ash .05 p. c; contains 98.5 p. c. of the pure salt. Impurities: Heavy metals, iron, barium, bromate, iodide, sulphate. Should be kept in well-closed containers. Dose, gr. 5-30 (.3-2 Gm.), ter die.

Preparations. - (Unoff.): Elixir, 8.5p. c, dose, 3 j-2 (4-8Ml. (Cc.)). Elixir Trium Bromidorum - Ammonium, potassium, sodium bromides, each 8 p. c, + cudbear .2, comp. elixir of almond q. s. 100.

Properties and Uses. - Like potassium bromide, but less depressing upon the arteries and muscles. Epilepsy, neurosis, delirium tremens, whooping-cough, rheumatism, menorrhagia.

Incompatibles: Acids, acid salts, spirit of nitrous ether.

Ammonii Valeras. Ammonium Valerate, NH4C5H9O2. - (Syn., Ammon. Valer., Ammonium Valerianate, Ammonii Valerianas; Fr. Valerianate d'Ammoniaque; Ger. Baldriansaures (Valeriansaures) Ammon, Valerianas Ammonicus.)

Manufacture: Saturate valeric acid with ammonia gas - i. e., pass gas into solution of the acid until it is neutral, crystallize. It is in colorless, white quadrangular plates, odor of valeric acid, sharp, sweetish taste, deliquescent, soluble in water (.3), alcohol (.6), ether; heated - fuses giving off vapors of ammonia and valeric acid, finally volatilizes - residue .05 p. c. Tests: 1. Aqueous solution heated with potassium hydroxide T. S. - evolves ammonia. 2. Supersaturated aqueous solution + sulphuric acid - oily layer of valeric acid rises to the surface; composition somewhat varying. Impurities: Heavy metals, acetate. Should be kept in well-closed containers. Dose, gr. 2-10 (.13-.6 Gm.).

Preparation. - (Unoff.): Elixir, 3.5 p. c, + chloroform .15, ammonia water to render alkaline, +, dose, 3j-2 (4-8 Ml. (Cc.)).

Properties and Uses. - Hysteria, epilepsy, chorea, neuralgia, nervous headache, insomnia, heart palpitation.

Ammonii Chloridum. Ammonium Chloride, NH4C1. - (Syn., Ammon. Chlor., Muriate of Ammonia, Ammonium (Muriaticum) Hydrochloratum'Depuratum, Sal (Ammoniacum) Ammoniac, Chloru-retum Ammonicum;- Fr. Chlorure d'Ammonium, Sel Ammoniac, Chlorhydrate d'Ammoniaque; Ger. Ammonium chloratum, Ammo-niumchlorid, Reiner Salmiak, Chlorammonium.)

Manufacture: The gas-liquor, an aqueous liquid condensed in the preparation and purification of illuminating gas from coal, contains chiefly ammonium carbonate, also sulphide, cyanide, and empyreumatic products; this liquor is distilled with lime and the generated ammonia gas passed into sulphuric acid, forming ammonium sulphate, which is then sublimed with sodium chloride - (NH4)2SO4 + 2NaCl = Na2SO4 + 2NH4Cl, or the ammonia gas may be passed directly into hydrochloric acid, forming the chloride. It is a white, crystalline, granular powder, odorless, cooling saline taste, somewhat hygroscopic, soluble in water (2.6), boiling water (1.4), alcohol (100), glycerin (8); heated volatilizes without fusing; cold aqueous solution - not immediately acid; contains 99.5 p. c. of the pure salt. Tests: 1. Aqueous solution (1 in 10) + silver nitrate T. S. - white curdy precipitate, insoluble in nitric acid, readily soluble in ammonia water. 2. Aqueous solution heated with potassium hydroxide T. S. - evolves ammonia. Impurities: Heavy metals, sulphocyanate, non-volatile substances. Dose, gr. 3-20 (.2-1.3 Gm.).