Prop., &c. Long, slender crystals, or a crystalline mass, freely soluble in both alcohol and water, and deliquescent in the air; taste sharp and cooling, and somewhat sweetish. Its solutions cannot be evaporated without loss of the ammonia; even the salt passes off in large quantities with the vapour of water. Its aqueous solution becomes alkaline on keeping, from decomposition of the acid. Distilled with anhydrous phosphoric acid, it is converted into ACETONITRILE. An aqueous solution of this salt was introduced into the Materia Medica by Boerhaave, and has since been extensively used as a diaphoretic and febrifuge, under the popular name of MINDERERUS SPIRIT, after Minderer or Mindererus, who extensively employed it and extolled its virtues. When pure, both the salt and its solutions are neutral to test-paper, and are wholly volatilised by heat. See Solutions.
Ammonium, Arseniate of. (NH4)3AsO4. Syn. Ammoniæ arse′nias, L. Prep. 1. (Neutral.) Saturate a warm concentrated solution of arsenic acid with carbonate of ammonium in slight excess; evaporate by a gentle heat, that crystals may form on cooling.
2. Ammonium, Binarseniate of. H(NH4)2AsO4. As above, but adding an additional equiv. of the acid, as soon as any excess of ammonia has been expelled by the heat employed to evaporate the solution.—Dose (of either). 1-24th to 1-12th gr.; in phthisis, certain skin diseases, &c. See Solutions (and below).
Ammonium, Arsenite of. NH4AsO2. Syn. Ammoniæ ar′senis, L. Prep. From a hot concentrated solution of arsenious acid, and sesquicarbonate of ammonium, as the last.—Used (chiefly) to make arsenite of iron. The properties and physiological effects of the above arsenical preparations are for the most part similar to those of arseniate and arsenate of potassa. They are all poisonous.
Ammonium, Benzoate of. Prep. 1. Dissolve benzoic acid in ammonia solution to saturation, then further add ammonia in slight excess, and crystallise by refrigeration, or in vacuo.
2. (Liquid; Solu′tio ammoniæ benzoa′tis, L.) As the last, but without evaporating the solution.
Prop., &c. Very soluble and very difficult to crystallise. If the solution is boiled for a short time and then abandoned to spontaneous evaporation, crystals of ACID BENZOATE OF AMMONIUM are deposited. It is used chiefly as a chemical test; but has been recently recommended in chronic bronchitis, old coughs, &c.; and to check the formation of chalk-stones and urinary calculi.—Dose, 10 to 15 gr.; (of the solution) 15 drops to 1 fl. dr., or more. See Benzoic Acid.
Ammonium, Bromide of. NH4Br. Syn. Ammo′′nii bromi′dum, A. bro′mis, L.; Hydrobromate d’ammoniaque, Bromure d’ammonium, Fr. A salt which is obtained from hydrobromic acid, bromide of iron, &c., by similar processes to those adopted for the iodide. The following process for the preparation of bromide of ammonium is from the formula for the new medicaments adopted by the Paris Pharmaceutical Society: “Add bromine very slowly to a solution of ammonia, with continual stirring, until the liquid remains faintly and persistently coloured by a slight excess of bromine.” It forms white prismatic crystals; and, in its general properties, resembles bromide of potassium. It is volatile, and easily decomposed.
Used as a nervine in hysterics; especially useful for sleeplessness where there is no organic disease; given in epilepsy when bromide of potassium fails.—Dose, 2 to 20 grains.
Ammonium, Carbonates of[47]—