Tin II Iodide

Tin(n) iodide is a less commonly encountered compound than other tin halides such as tin(II) fluoride, tin(II) chloride, or tin(lV) iodide. Although Snl2 has a simple stoichiometry, its chemical stracture is rather complex. Pale yellow acidic aqueous solutions of Snl2 afford brilliant red-orange crystals that contain an extended array in which some tin(ll) ions arc surrounded by six iodide anions, and others by seven. In the gas phase or in solution, monomeric tin(ll) halides are 

Department of Chemistry, West Virginia University, Morgantown, WV 26506. Departrrrent of Chemistry, Connectieut College, New London, CT 06320. 

Into a lOOmL one-necked round-bottomed flask is placed 20 mesh tin powder (1.5 g). The flask is clamped to a ring stand or other support, and placed on a 100 mL heating mantle. The flask is fitted with a reflux condenser topped with a Claisen adapter, and the reflux condenser is attached with rubber or plastic tubing to a cold water tap and a drain. The straight neck of the Claisen adapter is stoppered, and the curved neck is fitted with a gas inlet adapter (either a vacuum 

Iodine (2.1 g) and 2 M hydrochloric acid (15 mL) are measured out. The stopper on the Claisen adapter is removed, and the nitrogen flow to the flask is temporarily increased by closing the hose clamp. Into the open neck of the Claisen adapter is inserted a funnel, through which the iodine and dilute hydrochloric acid are added to the flask. Care should be taken so that the iodine crystals do not become stuck in the greased joint or in the condenser. After the addition is complete, the funnel is removed, the hose clamp is opened, and the stopper is replaced. The water to the reflux condenser is turned on, and the solution in the flask is then heated to reflux. As the sohd iodine is consumed, the solution becomes very pale yellow. The remaining tin should maintain a bright appearance for 5-10 min. 

The reaction mixture should not be stirred. Stirring causes Sn(II) to be formed while the solution is still cold, thus causing premature precipitation of the product. 

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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,... 

Interaction of the chloride with ammonia or sulfur dioxide is very violent, even at —75°C, and is vigorous with tin(II) bromide or tin(II) iodide. 

A considerable increase in sensitivity is obtained when bromide [41] or iodide [42] is used instead of chloride. In the bromide method, a yellow-orange complex is obtained (e = 2.9-10" at max 427 nm a = 0.29). The rhodium-tin(II) iodide complex is red and has an absorption maximum at 460 nm (e = 3.9-10 a = 0.34). In the iodide method, the optimum concentration of HCl is 1 M. The concentration of KI should not be lower than 4% in the final coloured solution. The quantity of SnCF only slightly affects the absorbance. The iodine liberated by air in the initial stage of the procedure is reduced when the SnCh is added. 

Tin(II) iodide method. To the sample solution containing not more than 50 pg of Rh, add 5 ml of the KI solution. Mix well, and heat for 15 min in a boiling water-bath. To the... 

Also, the tin(II) iodide method is less sensitive than the Sn(II) bromide method [75]. 

Germanium a)t 7V (ii), and Lead(ii) Halides and Halide Complexes. The crystal structures of hydrated tin(ii) chloride and bromide, and of anhydrous tin(ii) iodide, have been determined. That of SnQ2,2H20 is a more accurate redetermination and is shown in Figure 38. The tin atom is pyramidally... 

PURPOSE OP EXPERIMENT Prepare tin(II) iodide, Snl2/ tin(IV) iodide, Snl4, and study some physical and chemical properties of these compounds and of potassium iodide, KI. 

Calculate the volume of 12 M hydrochloric acid, HCl, solution required to react stoichiometrically with tin and also the mass of sodium iodide, Nal, required to react stoichiometrically with the tin dissolved in 12 M HCl solution in order to form tin(II) iodide, Snl2. Show clearly your calculations. 

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