Equations Sodium sulphide

Properties of Water-Soluble Sulphide. Dissolve sodium sulphide in water. Pour the solution into two test tubes. Test the reaction of the sodium sulphide solution with indicators (phenolphthalein, litmus). How can you explain what occurs Pass a stream of carbon dioxide through the solution in the second tube. Note the odour of the evolving gas. Write the equation of the reaction. 

How does iron(III) chloride react with sodium sulphide and potassium iodide Write the equations of the reactions. Under what conditions do iron(III) salts transform into iron(II) ones and vice versa ... 

Against this latter view is the fact that little or no sulphuric acid is formed unless the mixture is boiled for a long time. In alkaline solution, alkali sulphide and trithionate react to form thiosulphate,1 but alkaline solutions of sulphate and sulphide do not.2 It would appear, therefore, that the correct explanation lies in the reversible equation (6) (p. 195). This receives support from the fact that when lead thiosulphate is boiled with water it yields, in the first instance, lead sulphide and lead trithionate.3 Conversely, lead sulphide on digestion with potassium trithionate yields lead thiosulphate.4 Further, weakly alkaline solutions of sodium thiosulphate itself yield, on boiling, sodium sulphide and sodium trithionate, with only a trace of sulphate if boiled with sodium plumbite, lead sulphide is precipitated and sodium trithionate remains in solution. 

The reaction is really an extension of that on alkaline reduction, since the solution of sodium sulphide in water is alkaline. The complete equations are ... 

Experiment Treat 0.25 gram powdered stannous sulphide with sodium sulphide (Na2S) solution, warming for about 3 minutes. Does the solid dissolve Then add about 0.1 gram of powdered sulphur and warm a little longer. Does the stannous sulphide now go into solution Write equations and explain how the sulphur could have caused the stannous sulphide to dissolve. 

Sequential treatment of the enaminones 151 with phosphorus oxychloride and sodium sulphide yields the sulphur analogues 157, which yield isothiazoles by the action of hydroxylamine O-sulphonic acid (equation 69)87. 

How much sodium sulphide is formed by heating 100 gm. of sodium sulphate with charcoal The equation is —... 

Vinyl azides, which can be obtained from olefins, are converted in high yield into the corresponding carbonyl compounds by sodium sulphide in methanol." The mercury(ii)-catalysed hydrolysis of the vinyl chloride (32) shows an interesting solvent dependence in dichloromethane, acetic acid, benzene, or acetonitrile the yield of (33) is almost quantitative and no trace of (34) is observed, whereas in methanol 83% (34) and 6% (33) are obtained [equation (7)]." ... 

The selective oxidation of the sulphide grouping in the presence of the disulphide bond was observed when a methanolic solution of amide 46 was treated with an aqueous solution of sodium metaperiodate77 (equation 20). 

It is intriguing to note that this reaction scheme for the reduction of a sulphone to a sulphide leads to the same reaction stoichiometry as proposed originally by Bordwell in 1951. Which of the three reaction pathways predominates will depend on the relative activation barriers for each process in any given molecule. All are known. Process (1) is preferred in somewhat strained cyclic sulphones (equations 22 and 24), process (2) occurs in the strained naphtho[l, 8-hc]thiete 1,1-dioxide, 2, cleavage of which leads to a reasonably stabilized aryl carbanion (equation 29) and process (3) occurs in unstrained sulphones, as outlined in equations (26) to (28). Examples of other nucleophiles attacking strained sulphones are in fact known. For instance, the very strained sulphone, 2, is cleaved by hydride from LAH, by methyllithium in ether at 20°, by sodium hydroxide in refluxing aqueous dioxane, and by lithium anilide in ether/THF at room temperature. In each case, the product resulted from a nucleophilic attack at the sulphonyl sulphur atom. Other examples of this process include the attack of hydroxide ion on highly strained thiirene S, S-dioxides , and an attack on norbornadienyl sulphone by methyllithium in ice-cold THF . ... 

For preparing larger quantities of the hydrosulphide it is more convenient to carry out the reaction in the presence of an excess of the precipitant—say 5 grins, of sodium with a mixture of 10 grms. of absolute alcohol and 100 c.c. of pure dry benzene, more alcohol is added from time to time to keep the ethoxide in soln. until all the sodium is dissolved. This liquid is treated with hydrogen sulphide as before. The reaction seems to be quantitative and to be expressed by the equation C2H50Na+H28=C2H50H+NaHS potassium salt is prepared in a similar manner. 

Reduction of MoIybdenum(VI) and Tungsten VI) Compounds. Pour 3 ml of an ammonium molybdate solution into each of four test tubes, acidify with a 2 N hydrochloric acid solution, and heat up to boiling. Add solutions of sulphuric acid, hydrogen sulphide, and tin(Il) chloride to three of the tubes, respectively, and throw one or two small pieces of zinc into the last tube. Perform similar experiments using sodium tungstate as the initial reactant. Write the equations of the reactions. 

What happens when iron(III) chloride reacts with hydrogen sulphide and ammonium sulphide Conduct the relevant reactions and write their equations. List the properties of iron(III) salts. How can sodium ferrite be prepared Which salts hydrolyze more strongly—ferrites or iron(III) salts What does this depend on ... 

Arsenic(in) and Arsenic(V) Sulphides. Pass a stream of hydrogen sulphide into sodium arsenite and sodium arsenate solutions. What happens Run similar experiments with acidified solutions of the same salts. What do you observe in this case Write the equations of the reactions and explain the occurring phenomena. 

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