Hydrogen Sulphide ITS

Organic materials Corrosive vapours are sometimes emitted by organic materials used either in packaging or in the manufactured article, and may be troublesome in confined spaces. Some woods, particularly unseasoned oak and sweet chestnut, produce acetic acid (see Section 18.10), and certain polymers used in paints, adhesives and plastics may liberate such corrosive vapours as formic acid and hydrogen sulphide . It may be necessary to carry out exposure trials, particularly where materials capable of liberating formaldehyde or formic acid are involved. Most corrosion problems of this kind can be prevented by using desiccants, and in many cases they are confined to imperfectly cured materials. For an excellent review see Reference 9. 

Hydroxy-4-methylthiazole-2(3//)thione carbamates, e.g. the cyclohexyl derivative 336, are precursors for monoalkylaminium cation radicals, which cannot be prepared from 2-thioxopyridinyloxycarbamates. The carbamate is obtained from 3-hydroxy-4-methylthiazole-2(3//)-thione and cyclohexyl isocyanate. When irradiated in the presence of malonic acid and /-butyl hydrogen sulphide it yields the cyclohexylaminium cation... 

Chloro - pentammino - iridium Chloride, [Ir(NH3)sCl]Cl2, is formed by the action of ammonia on iridium trichloride, iridium tetrachloride, or the ehloro-double salts. It may also be prepared from chloro-pentammino-iridium sulphate by treating it with barium chloride. Prepared by the first method it separates in wine-coloured crystals, whilst by the second method it is yellow. The red colour of the first product is due to a small quantity of iridium trichloride, which separates with the chloro-ehloride and may be removed by heating the hot aqueous solution with hydrogen sulphide. It crystallises in 1 Jorgensen, J. prakt. Ghem., 1888, 34, 394 Palmaer, Ber., 1891, 24, 2090. 

In agreement with the relative reactivities of the alkali hydroxides and carbonates towards hydrogen sulphide, it has been observed that the blackening of basic lead carbonate by the gas is due to the conversion into sulphide of the lead hydroxide only and not of the carbonate.6... 

These hydrosulphides of the alkaline earth metals are soluble in water and therefore, by treating an emulsion of the normal sulphides with a current of hydrogen sulphide, it is possible to obtain solutions of the hydrosulphides 1 Ca(SH)2, Sr(SH) Ba(SH)2 and Mg(SH) . 

Sulphur Thiocyanate, S(SCN)2, is formed as colourless, pearly crystals, when a solution of thiocyanogen in ether reacts with dry hydrogen sulphide. It decomposes at atmospheric temperatures. Heated in an open tube on a water-bath it darkens rapidly and then suddenly decomposes, evolving orange fumes. A solution of sulphur thiocyanate in a mixture of ether and benzene does not react with powdered iron, but on the addition of a drop of water the characteristic red colour of ferric thiocyanate develops immediately. By this reaction sulphur thiocyanate can be distinguished from free thiocyanogen.2... 

This powder takes fire in air at a summer s heat, and burns with a white flame to form phosphoric acid it is violently oxidized and dissolved by nitric acid, forming sulphuric and phosphoric acids it inflames in the vapours of nitrogen peroxide it has no odour when freshly prepared, but after exposure to air, it acquires the smell of hydrogen sulphide it forms a turbid soln. when treated with water, which deposits sulphur and smells of hydrogen sulphide it evolves ammonia when treated with alkali-lye and it is dissolved by hot alkali-lye but not by aq. ammonia or hydrochloric acid. The product is probably a mixture of phosphorus sulphide, and ammonium salts. 

Thiols can be prepared by the action of alkyl halides with an excess of KOH and hydrogen sulphide. It is an SN2 reaction and involves the generation of a hydrogen sulphide anion (HS ) as nucleophile. In this reaction, there is the possibility of the product being ionised and reacting with a second molecule of alkyl halide to produce a thioether (RSR) as a by-product. An excess of hydrogen sulphide is normally used to avoid this problem. 

This highly reactive compound may be utilized for various reactions (Zincke [20, 21]). For example, with hydrogen sulphide it forms a tetranitro derivative of diphenyl sulphide (Zincke and Weisspfennig [22]). 

Potassium monosulphide, KaS.—The sulphide can be formed by direct union of the elements,13 by reduction of potassium sulphate with hydrogen or charcoal, and by the interaction of aqueous solutions of potassium hydroxide and potassium hydrogen sulphide. It is also produced by the action of sulphur on a solution of excess of potassium in liquid ammonia.14 On evaporation of its aqueous solution in vacuum at low temperature, the pentahydrate16 crystallizes. A dihydrate and a dodecahydrate are also known.18 The anhydrous salt can be obtained... 

It does not react appreciably with sulphur dioxide at dull redness.13 Raised to white heat in a current of hydrogen sulphide, it yields ferrous sulphide, accompanied by the evolution of hydrogen, sulphur dioxide, and a little sulphur trioxide.14... 

If iron wire is used exposed in a bundle to the hydrogen sulphide, it readily becomes encrusted with tiny crystals, silver-white in appearance when first prepared. The crystals 1 are regarded as belonging to the hexagonal system. 

A labile phase of iron disulphide occurs in nature under the name melnikovite It is a black, finely divided substance which impregnates certain miocene clays in Russia, and differs in many respects from the black hydrated sulphide of iron usually found in black muds of lakes. In composition it corresponds to the formula FeS2. It is magnetic, and its true density is probably 4 2 to 4 3. Cold, dilute hydrochloric acid readily attacks it, evolving hydrogen sulphide. It has probably been derived from a colloidal deposit of an iron sulphide.3... 

At high temperatures the metal will react slowly with certain gases. With carbon monoxide it produces a surface film of carbide, with nitrogen it produces a nitride film, and with hydrogen sulphide it reacts to form molybdenum disulphide. All of these films presumably interfere with the flow of gas to the metal surface, and in each case only a thin film of the product arises. Molybdenum is also very resistant to corrosive attack by mineral acids except for those such as nitric acid or chromic... 

Hydrogen Sulphide. — An important compound of sulphur is the gas, hydrogen sulphide. It is formed in many... 

On treating this dibromo compound with hydrogen sulphide, it decomposes to form hydrobromic acid and trichlorovinyl arsine and deposit sulphur ... 

When an alkaline solution of the acid is treated wilii hydrogen sulphide, it yields dibenzylthioarsinic add, (CbHs.CH2)2AsS.SH, consisting of white, glistening plates, M.pt. 197° to 199° C., soluble in alcohol, benzene, and acetic add. 

The ortho di-amino benzene prepared by the reduction of ortho-nitraniline is of special interest because of certain condensation reactions which it undergoes with aldehydes, ketones and nitrous acid. The meta compound also shows a characteristic reaction with nitrous acid. The para compound is readily oxidized and gives characteristic color reactions with ferric chloride and hydrogen sulphide. It is of importance in the preparation of dyes. All of these di-amines are colorless, crystalline solids which can be distilled. 

Make a white cardboard model of a tabby cat, and treat with a groundwork of antimony chloride, cross by markings of lead acetate. Now when antimony chloride and lead acetate are exposed to the fiunes of hydrogen sulphide, it gives the former (previoudy invisible), an orange tint and the latter a black one under such circumstances our cat becomes a tiger. 

An essential portion of sulphur in the atmosphere comes from hydrogen sulphide. It makes up 46.1%, whereas the proportions of sulphur corresponding to sulphur dioxide and to sulphites together with sulphates are... 

Thus the degree of OM decomposition, amounting to 70—80% of the initial amount (at 20°C) in the long-term experiment, is close to that in wata bodies containing hydrogen sulphides it is evidently lower for the oxygen-containing ones. 

Carbon reduces it partldly. Iodic acid decomposes it in part, liberating iodine (Uansen). With a current of hydrogen sulphide it forms Sb SjO. Sulphide of carbon reduces it ( Muller). We have also —... 

Trimethylstibine sulphide, (CHg)3SbS.—An ether solution of trimethylstibine is warmed with sulphur, or an aqueous solution of trimethylstibine oxide is treated with hydrogen sulphide. The sulphide also occurs when an ether solution of trimethylstibine dibromide is treated with potassium ethylate and the filtrate subjected to the action of a current of hydrogen sulphide. It forms crystals from alcohol, M.pt. 168° C. with decomposition, is sparingly soluble in cold water, being more soluble in alcohol or ether. 

Tetraethylstibonium nitrate, (C2H5)4SbNOg, forms long, deliquescent needles.The corresponding sulphate yields small, deliquescent crystals. A hydrosulphide is obtained by saturating the hydroxide in aqueous solution with hydrogen sulphide it is a yellow oil, soluble in water or alcohol. 

Tri-m-tolylstibine sulphide, (CH3.C6H4)3SbS, occurs when an alcoholic ammomacal solution of the dichloride is treated with hydrogen sulphide. It crystallises from alcohol in needles, M.pt. 162° to 163° C.,... 

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