Hydrogen sulphide physical properties

Hydrogen sulphide occurs naturally, e.g. in natural gas and petroleum, volcanic gases, and from decaying organic matter. It may be present near oil wells and where petroleum is processed. Commercially it is obtained as a by-product from many chemical reactions including off-gas in the production of some synthetic polymers (e.g. rayon, nylon) from petroleum products, and by the action of dilute mineral acids on metal sulphides. Physical properties are summarized in Table 9.14 and effects of temperature on vapour pressure are shown in Figure 9.5. 

Physical Properties.—Hydrogen sulphide is a colourless gas with the unpleasant odour which is commonly associated with a bad egg (see p. 48), the smell of which is actually due largely to this gas. It is 1-189 times as dense as air and one litre at N.T.P. weighs 1-539 grams.5... 

Physical Properties.—Hydrogen selenide is a colourless gas the odour of which at first suggests hydrogen sulphide, but afterwards is unpleasantly pungent, causing headache and affecting the mucous membrane of the nose in such a way as to induce a form of catarrh. 

Stannic sulphide, SnS2, is the higher sulphide of tin, and can be prepared by direct combination of the metal or, still better, of the lower sulphide, SnS, with sulphur. Under ordinary conditions these two substances will not react at a temperature below that which will decompose stannic sulphide. If, however, they are mixed with ammonium chloride the presence of this substance makes possible the combination at a lower temperature. The stannic sulphide formed in this way appears as soft, glistening, yellow crystals. It is used as a bronzing powder, and is known under the name of mosaic gold. In physical properties it is very different from the stannic sulphide which can be precipitated by hydrogen sulphide from a solution of stannic chloride. 

Synthesis of Isothiazoles, Isothiazolines, and Isothiazolidines 151 From amidoketones and hydrogen sulphide (Type A C-C-C-N + S) 151 From iminonitriles and mercaptoacetic acid derivatives (Type B C-C-N + S-C) 151 From cyclisation of enaminothiones (Type C N-C-C-C-S) 152 From sulphonamidoacetates and diethyl oxalate (N-S-C + C-C) 152 From ketenes and sulphur di-imides (N-S-C + C-C) 152 Physical Properties of Isothiazoles and Isothiazolines 152 Chemical Properties of Isothiazoles, Isothiazolines, and Isothiazolidines 153... 

Table 20. Some Physical Properties of Hydrogen Sulphide...

Other Physical Properties.—Conformational information for thiols and sulphides can be obtained from enthalpy of formation data. Proton-transfer of benzyl-mercaptan (protonation at sulphur with CF3SO3H, and de-protonation by imidazole) has been studied. Thermodynamic parameters for acidity constants of substituted benzenethiols, and for hydrogen-bonding interactions between alkanols and di-n-octyl sulphide and the analogous ether and N-methylamine, reveal a dominant electronic influence of the orM<>-substituent, and substantially higher hydrogen-bond acceptor ability for the aliphatic sulphide than is generally assumed. ... 

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