Lond. Acetate of Soda.

Syn. Acetate de Soude (F.), Essigsaures Natron ( G.), Acetato di Soda (i..).

This salt is prepared in considerable quantity by the manufacturers of pyroligneous acid. It is formed by saturating the impure acid, distilled from wood, with chalk, then boiling the mixture and completing the saturation with slaked lime. A black scum forms, which being removed, the acetate is next decomposed by sulphate of soda; an insoluble sulphate of lime and a soluble acetate of soda are the result. After the sulphate, which carries down with it many impurities, has fully subsided, the solution of the acetate is decanted, evaporated to a pellicle, and crystallised. It is purified by submitting it to the action of heat till it fuses, after which it is again dissolved in water, filtered and re-crystallised.

Qualities. - Acetate of soda as it is usually procured, is a white irregularly crystallised salt, with a sharp, bitterish, not unpleasant taste. When crystallised with care, the crystals are a modification of the oblique, rhombic prism. Exposed to the air, the crystals slowly effloresce, and lose about 40 per cent. of their weight: at 550° Fahrenheit, they lose the whole of their water of crystallisation, and undergo igneous fusion without decomposition, which takes place at 600°. Acetate of soda is soluble in 3 parts of water at 60°, and in 24 parts of alcohol. It is a compound of 1 eq. of acetic acid = 51.48+ 1 of soda'= 31.3 + 6 of water = 54-equiv. 136.78.

Medical properties and uses. - Acetate of soda is diuretic; but although it is not deliquescent, and> consequently is more manageable than the acetate of potassa, yet it is seldom ordered. The dose is from Эj. to. 3j. It is chiefly used for the preparation of acetic acid.

Officinal preparation. - Acidum aceticum.