Sodium trisulphide

H. Quantin showed that when sodium carbonate and carbon tetrachloride are heated together, sodium chloride, carbon dioxide, and carbonyl chloride are produced. M. J. Fordos and A. Gelis obtained a mixture of sodium sulphide and thiosulphate by heating an intimate mixture of the sodium carbonate and sulphur to 275° while H. E. Schone says that if the mixture is fused, a mixture of sodium trisulphide and sulphate is formed. J. B. Senderens found that sulphur acts slowly on a soln. 

Laboratory Preparation of Iron Disulphide.—In the laboratory iron disulphide may be prepared by several wet methods. Thus, it is formed when ferrous sulphide is boiled with flowers of sulphur and when sodium trisulphide is added slowly to a boiling solution of ferrous sulphate, provided excess of the trisulphide is avoided. Sulphur is simultaneously precipitated.4 It is obtained also by boiling the freshly precipitated monosulphide suspended in water with sulphur in the absence of alkalies 5 by the action of sodium thiosulphate solution upon ferrous sulphate6 in sealed tubes at temperatures even below 100° C. —... 

Arsenic. The presence of arsenie in an organie eompound is generally revealed by the formation of a dull grey mirror of arsenic on the walls of the test-tube when the eompound is fused with sodium in the Lassaigne teat. Usually sufficient arsenic is found in the fusion solution to give a yellow precipitate of arsenic trisulphide when the solution is acidified with hydrochloric acid and treated with hydrogen sulphide. 

It is recommended that the eompound be fused with a mixture of sodium carbonate (2 parts) and sodium peroxide (1 part) as in the test for Plvoaphoms. Extract the fused mass with water, filter, and acidify with dilute hydrochloric acid. Pass hydrogen sulphide through the hot solution arsenic is precipitated as yellow arsenic sulphide. If antimony is present, it will be precipitated as orange antimony trisulphide. 

Sulphur and selenium unite when warmed with the metal 51 when sulphur is triturated with sodium, the reaction proceeds with explosive violence which can be moderated by dilution with common salt. Under boiling toluene, sulphur forms the trisulphide Na2S3. Selenium forms the monoselenide, Na2Se, when heated with sodium. Sodium is attacked by hydrogen sulphide at ordinary temp., and at the fusion point the metal bums in the gas. Gaseous ammonia reacts readily with sodium, and liquid ammonia forms blue soln.—the so-called alkali-ammoniums. 

This seems to suggest that the sulphur unit is S2. This unit is capable of uniting with hydrogen sulphide to form the trisulphide, H2S3 but sodium sulphite can only combine with one atom of sulphur to yield thiosulphate. The catalytic activity of the hydrogen sulphide would thus appear to be due to its ability to absorb a whole sulphur unit, Sa, and subsequently to give up, on reduction, each atom of sulphur separately, thus ... 

Fusion with sodium thiosulphate yields arsenic trisulphide.7... 

Sodium hydrosulphite reduces arsenates and arsenites, yielding precipitates containing sulphides the composition of which varies with conditions. In strongly acid solutions arsenic trisulphide is the main product.2 Sodium thiosulphate also precipitates arsenic as the trisulphide from acid solutions,3 but the amount of precipitation depends on the nature and concentration of the acid present. Thus, with hydrochloric, perchloric or sulphuric acid, the precipitation reaches a maximum of 50 to 80 per cent, for 0-1N acid,4 and above this concentration the amount of precipitation falls to zero with hydrochloric acid but passes through a minimum with perchloric acid at N concentration and with sulphuric acid at 2 to 3N concentration. At still higher acid concentrations precipitation becomes almost quantitative. 

When the trisulphide is ignited with sodium carbonate and nitrate, sulphate and arsenate are formed ... 

How do the trisulphides of arsenic and antimony behave when treated with a solution of Na S With a solution of Na S-S How does the solution obtained with sodium polysulphide behave when it is acidified Give equations for all the reactions. 

The trisulphide in the form of trihydrate was similarly prepared by Bottger as golden-yellow crystals. The anhydrous substance is produced by the interaction of sodium monosulphide and the calculated amount of sulphur in boiling toluene.5 Its melting-point is given by Friedrich 8 as 320° C. Its heat of formation in solution is 106-4 Cal.7... 

Compounds Bis-dimethylstibinyl oxide Bis(dimethylthallium) acetylide Butyllithium Nonacarbonyldiiron Octacarbonyldicobalt Pentacarbonyliron Tetracarbonylnickel Dibismuth trisulphide Dicaesium selenide Dicerium trisulphide Digold trisulphide Europium (II) sulphide Germanium (II) sulphide Iron disulphide Iron (II) sulphide Manganese (II) sulphide Mercury (II) sulphide Molybdenum (IV) sulphide Potassium sulphide Rhenium (VII) sulphide Silver sulphide Sodium disulphide Sodium polysulphide Sodium sulphide Tin (11) sulphide Tin (IV) sulphide Titanium (IV) sulphide Uranium (IV) sulphide ... 

Colloidal Tungsten Trisulphide.—It W as obser% ed by Berzelius that when the freshly precipitated trisulphide is washed with water, it dissolves to a slight extent, forming a yellow solution. If the precipitate is boiled with pure water it dissolves in considerable quantity, yielding a brownish-yellow solution. Winssinger obtained a dark brown solution of tungsten trisulphide by adding to a solution of sodium thiosulphate a little more dilute hydrochloric acid than was... 

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