Sodium Pyrophosphate (Crystallised). Syn. Sodæ pyrophosphas crystallisata. (P. Cod.) Prep. This salt may be obtained by heating, gently at first, and afterwards to a red heat, crystallised phosphate of sodium in a platinum crucible until all the water is driven off, and the salt has become fused. Dissolve the
fused mass in water, filter, and concentrate until it has a density of 1·20, and crystallise in the cold.
Sodium, Salicylate of. Syn. Sodæ salicylus. Prep. Made by neutralising a solution of pure salicylic acid with caustic soda, and evaporating to dryness. It must be purified by crystallisation from alcohol. Antipyretic; given in acute rheumatism.—Dose, 10 to 20 grams.
Sodium Santonate. Syn. Sodæ santonas. This salt is made by digesting an alcoholic solution of santonic acid with carbonate of soda, evaporating, redissolving in strong alcohol, and crystallising.
Sodium, Sesquicarbonate of. Na4H2(CO3)3. A salt found native on the banks of the soda lakes of Sotrena, in Africa, whence it is exported as ‘Trona.’
Sodium Silicate. See Glass, Soluble.
Sodium, Stan′nate of. Na2SnO3. Prep. (Greenwood & Co.) Caustic soda, 22 lbs., is heated to low redness in an iron crucible, when nitrate of sodium, 8 lbs., and common salt, 4 lbs., are added; when the mixture is at a ‘fluxing heat,’ 10 lbs. of feathered block tin is stirred in with an iron rod, both the stirring and heat being continued until the mass becomes red hot and ‘pasty,’ and ammoniacal fumes are given off. The product may be purified by solution and crystallisation. Patented. (See below.)
Sodium, Stan′nite of. Prep. (Greenwood & Co.) From caustic soda, 131⁄2 lbs.; feathered block tin and common salt, of each 4 lbs.; as the last. Patented. Both the above are used to prepare tin mordants (about 12 oz. to water, 1 gall.). The stannate and stannite of potassium are prepared in a similar manner.
Sodium Sulphate. Syn. Sodæ sulphis. Prep. Pass sulphurous acid to saturation through a solution of carbonate of soda. Used internally for sarcina ventriculi, and externally as an application in skin diseases of fungous origin. Hyposulphate of soda is employed in the same cases.
Sodium, Sul′phate of. Na2SO4.10Aq. Syn. Glauber’s salt; Sodæ sulphas (B. P., Ph. L., E., & D.), Sal catharticus Glauberi†, L. This is obtained as a secondary product in various chemical processes; but it may be easily formed directly from its constituents.