Sulphuric Acid, Anhy′drous. SO3. Syn. Sulphuric anhydride, Dry sulphuric acid; Acidum sulphuricum sine aquâ, L. Prep. 1. By heating Nordhausen acid to about 100° Fahr. in a glass retort connected with a well-cooled receiver.
2. By distilling anhydrous bisulphate of soda, which has previously been raised to a low red heat in an earthen retort, to which a receiver is fitted without the aid of corks.
3. (Barreswill.) 2 parts of the strongest oil of vitriol are gradually added to 3 parts of anhydrous phosphoric acid, contained in a retort surrounded by a freezing mixture; when the compound has assumed a brown colour, the retort is removed from the bath, and connected with a receiver which is set there in its place; a gentle heat is now applied to it, when white vapours pass over into the receiver, and condense there under the form of beautiful silky crystals. The product equals in weight that of the phosphorus originally employed. “If a few drops of water be added, a dangerous explosion ensues.”
Prop. White, silky, asbestos-like crystals,
deliquescing rapidly, and fuming in the air; put into water, it hisses like a red-hot iron; it melts at 77°, and rapidly volatilises at 86° Fahr.; it does not redden dry litmus paper; sp. gr. 1·97 at 78° Fahr.
Sulphuric Acid, Aromat′ic. Syn. Elixir of vitriol, Acid e. of v.; Acidum sulphuricum aromaticum (B. P., Ph. E. & D.), L. Prep. 1. (Ph. E. & D.) Oil of vitriol, 31⁄2 fl. oz.; rectified spirit, 11⁄2 pint; mix, add of powdered cinnamon, 11⁄2 oz.; powdered ginger, 1 oz.; digest for 6 days (7 days—Ph. D.), and filter. Sp. gr. ·974—Ph. D.
2. (Wholesale.) From compound tincture of cinnamon, 1 gall.; oil of vitriol, 1 lb.; mix, and in a week filter—Dose, 10 to 30 drops, in the same case as the dilute acid.
3. (B. P.) Sulphuric acid, 3; rectified spirit, 40; cinnamon, in powder, 2; ginger, in powder, 11⁄4; mix the acid gradually with the spirit, add the powders, macerate for 7 days, and filter.—Dose, 5 to 30 minims.
Sulphuric Acid, Dilute′. Syn. Spirit of vitriol; Acidum sulphuricum dilutum (B. P., Ph. L., E., & D.), L. Prep. 1. (Ph. L.) Take of sulphuric acid, 15 fl. dr., and dilute it gradually with distilled water, q. s. to make the whole exactly measure a pint. Sp. gr. 1·103. “1 fl. oz. of this acid is exactly saturated by 216 gr. of crystallised carbonate of soda.”
2. (Ph. E.) Sulphuric acid, 1 fl. oz.; water, 13 fl. oz. Sp. gr. 1·090.