Silver sulphite

The solution of silver nitrate is acidified with dilute nitric acid, boiled so as to decompose any silver sulphite that might have been formed, and the precipitate filtered, washed, etc. 

When silver sulphite or a mixture of sodium sulphite and silver nitrate is heated in boiling aqueous solution, decomposition occurs with formation of silver dithionate.1... 

If the reagent is added in excess, white silver sulphite is also precipitated (cf. Section IV.4, reaction 3). 

Sodium dithionate, Na2S206.1—The dithionate is obtained by the action of sodium carbonate on barium dithionate.2 It is the principal product formed by boiling sodium silver sulphite with water 3... 

Silver sulphite, Ag2SOs.—The sulphite is prepared by precipitating silver nitrate with the theoretical proportion of sulphurous add or sodium sulphite, the salt being decomposed by excess of the acid, and dissolved by excess of the sulphite. It is a white substance, its colour changing under the influence of light to purple and then to black. Its solubility 4 in water is less than 1 20000. When boiled with water, it decomposes in accordance with the equation... 

With the salts of certain weak acids, such as carbonic, sulphurous, and nitrous acids, an additional factor contributing to the increased solubility is the actual disappearance of the acid from solution either spontaneously, or on gentle warming. An explanation is thus provided for the well-known solubility of the sparingly soluble sulphites, carbonates, oxalates, phosphates(V), arsenites(III), arsenates(V), cyanides (with the exception of silver cyanide, which is actually a salt of the strong acid H[Ag(CN)2]), fluorides, acetates, and salts of other organic acids in strong acids. 

Magnesium fluorosilicate Mercuric chloride Nickel chloride Nickel sulphate Potassium bisulphate Potassium bisulphite Potassium sulphite Silver nitrate... 

When this argentic sulphite is boiled with water, it becomes black, owing to the separation of metallic silver s—... 

An accurate electrometric method applicable to soluble sulphides consists in precipitating as silver sulphide in alkaline solution by titration with standard ammoniacal silver solution.6 The change of E.M.F. at the end-point is considerable. The method is satisfactory in the presence of sulphite, sulphate, thiosulphate, polysulphide or chloride. 

Sulphides, Sulphites, and Thiosulphates. On I ouriug I cc. of the 1 20 aqueous solution into 10 it. of decinurnwd silver nitrate solution, a yellowish-while, precipitate forms. winch should not become darker (gray to brownish to lihicki on... 

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