Stannous salts

Stannic and stannous chloride are best prepared by the reaction of chlorine with tin metal. Stannous salts are generally prepared by double decomposition reactions of stannous chloride, stannous oxide, or stannous hydroxide with the appropriate reagents. MetaUic stannates are prepared either by direct double decomposition or by fusion of stannic oxide with the desired metal hydroxide or carbonate. Approximately 80% of inorganic tin chemicals consumption is accounted for by tin chlorides and tin oxides. 

Staono-. stannous, stanno-, tin(II). -azetat, n. stannous acetate, tin(II) acetate, -chlorid, n. stannous chloride, tin(II) chloride, -chlor-wasserstoffsMure, /. chlorostannous acid, -hydroxyd, n. stannous hydroxide, tin(II) hydroxide. -jodid, n. stannous iodide, tin(II) iodide. -jodwasserstoffsaure, /. iodostannous acid, -oxyd, n. stannous oxide, tin(II) oxide, -salz, n. stannous salt, tin(II) salt, -sulfid, n. stannous sulfide, tin(II) sulfide. -verbindung, /, stannous compoimd, tin(II) compound,... 

Tin anodes dissolve by etching corrosion in acid baths based on stannous salts, but in the alkaline stannate bath they undergo transpassive dissolution via an oxide film. In the latter the OH" ion is responsible for both film dissolution and for complexing the tin. Anodes must not be left idle because the film dissolves and thereafter corrosion produces the detrimental divalent stannite oxyanion. Anodes are introduced live at the start of deposition, and transpassive corrosion is established by observing the colour of the film... 

The method of Y. Meyer, reduction of the diazonium chlorides to arylhydrazines with strongly acid stannous chloride solution, is less elegant. The difference in the actions of stannous salt in acid and in alkaline solution should be noted. 

The method is based upon the precipitation of a solution of a stannous salt by hydrogen sulfide. The most available stannous salt is the chloride, which may... 

Aqueous solutions of the salts, or of tellurium dioxide in acids, easily undergo reduction.to elementary tellurium. Phosphorus, phosphorous acid,-7 hypophosphorous acid,8 sulphurous acid,9 thiosulphuric acid,10 hyposulphurous acid,11 hydriodic acid,12 hydrogen sulphide,13 ferrous salts, stannous salts,14 hydrazine 15 and phenylhydrazine, as well as various metals,18 e.g. zinc, iron, tin, cadmium, antimony and copper, are able to effect this reduction. 

The addition of slaked lime and the initiation of polymerization reactions with 11.Og and feme 01 stannous salts are techniques employed to lemove aminophenols from wastewaters... 

Sulfates, [CAS 7488-55-3], Stannous sulfate, a white powder soluble in water and H2SO4, is obtained commercially by action of H2SO4 on SnCU or Sn. Stannic sulfate may be formed by the solution of stannic hydroxide in dilute H2SO4, or by action of oxidizing agents on stannous salts. 

Sulfides. Stannous sulfide SnS, dark brown precipitate, by reaction of stannous salt solution and H2S, insoluble in sodium sulfide solution but soluble in sodium polysulfide solution, forming sodium thiostannate stannic sulfide SnS , yellow precipitate, by reaction of stannic salt solution and H>S, soluble in sodium sulfide solution, forming sodium thiostannate. 

They also tried soln. of cupric chloride in acetic acid, formic acid, acetone, and methyl and ethyl alcohols. With 0-37, 0-62, and 0-925 litre of soln. with a mol of cupric bromide, 0-515, 0-120, and 0-000 litre of nitric oxide were respectively absorbed. They also tried soln. of cupric bromide in ethyl alcohol. E. Peligot found that nitric oxide is absorbed by aq. soln. of stannous salts (vide infra) and chromous salts. According to G. Chesneau, a soln. of ckromous chloride absorbs nitric oxide in the ratio CrCl2 NO=3 1, and the blue liquid becomes dark red. When heated, the nitric oxide is not expelled as in the case of ferrous salts, but the liquid becomes greenish-brown, and the nitric oxide is reduced to ammonia or hydroxylamine. The action of nitric oxide on soln. of chromous salts was also studied by V. Kohlschiitter, and J. Sand and O. Burger. 

When an excess of nitric acid of 10-50 per cent, strength is treated in the cold with stannous salt soln., hydroxylamine salts are the primary end-product of the reaction, but when the conditions of temp, and cone, are such that the nitric acid and the hydroxylamine salts react, then nitrous oxide is the. chief product together with small amounts of nitHe oxide, nitrogen and traces of nitrogen peroxide. No ammonium salts are formed. When stannous salts are used in excess over the nitric acid, the reaction takes place with hydroxylamine and ammonium salts as the products either in hot or cold soln., but the reaction is very slow in the latter case. When an excess of nitric acid is treated with titanous salt soln., the reaction takes place very rapidly with the formation of nitric oxide as the chief... 

Gosselin RE, Smith RP, Hedge HC. 1984. Stannic and stannous salts. In Clinical toxicology of commercial products. 5th ed. Baltimore, MD Williams and Wilkins, 11-146. 

Black precipitate of bismuth metal Violet coloration with stannous salts the following interfere strong reducing agents (hydrogen sulfide, dithionites, sulfites, and selenites) also, U, V, Te, Hg, Bi, Au, Pd, Se, Sb... 

M T - stannous salt of long fatty acid Union Carbide Silicone... 

This salt can be prepared by the action of hydrochloric acid upon metallic tin, but since the action is exceedingly slow, it is hastened by the addition of a very small quantity of nitric acid, which oxidizes the tin. Nitric acid is ordinarily reduced only to the oxide NO by its action upon a metal but in the course of this preparation no red fumes of oxides of nitrogen are found to escape, because, under the influence of tin and stannous chloride, the reduction does not stop at nitric oxide, but continues to the lowest possible step, which is ammonia or in this case its salt, ammonium chloride. Stannous salts are oxidized quite readily to stannic by the oxygen of the air to prevent this happening during the evaporation of the solution, an excess of metallic tin is kept in the liquid. 

There are two series of compounds of tin and the halogens those related to stannous oxide, SnO, in which the metal has a valence of 2 (stannous salts), and those related to stannic oxide, Sn02, in which it has a valence of 4 (stannic salts). The compounds with lower valence are usually prepared by the action of the halogen acids on the metal. Stannous chloride, for example, is formed when hydrochloric acid reacts with tin. Stannic salts, on the other hand, are prepared by the reaction of tin and the free halogen. In this preparation stannic bromide results from the reaction of bromine and tin. The reaction between the two ele-... 

Hydrolysis of Stannous Salts. Dissolve 0.5 gram crystallized SnCl2-2H20 in a few drops of water. A clear solution can be obtained if the preparation is fresh. Dilute the solution with water and note the white precipitate. Add a little HC1 and note that the precipitate redissolves. 

Stannous salts in which tin displays the lower valence of 2 are derivatives of the hydroxide Sn(OH)2. That salts, such as... 

Reducing Action of Stannous Salts, (a) Add SnCl2 solution drop by drop, to 2 cc. of HgCl2 solution diluted with 10 cc. of water. Notice the white precipitate which turns gray and then black with more of the reagent. 

III.18 TIN, Sn (Ar 118-69) - Tin(II) Tin is a silver-white metal which is malleable and ductile at ordinary temperatures, but at low temperatures it becomes brittle due to transformation into a different allotropic modification. It melts at 231-8°C. The metal dissolves slowly in dilute hydrochloric and sulphuric acid with the formation of tin(II) (stannous) salts ... 

Cacotheline reagent (a nitro-derivative of brucine, C21H2101N3) violet colouration with stannous salts. The test solution should be acid (2m HC1), and if tin is in the quadrivalent state, it should be reduced previously with aluminium or magnesium, and the solution filtered. 

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