Sulphide solid

Heavy Metals and Arsenic. — Evaporate to dryness on (lie sand-bath a mixture of 5 gm. of potassium liisulphite and 5 cc. of sulphuric acid (sp. gr. 1.84), and dissolve ll)c residue in 20 cc. of water. 10 cc. of this solution. should show ne change on the addition of hydrogen. sulphide water. On adding to the other 10 cc. of the potassium sulphide solid ion a solution of ammonium molylxhito in nitric, acid, mid hen t mg the mixture to 70 to 80° C., the liquid should not impure a yellow color, nor should a yellow precipitate Form. 

Tsu] Tsurkan, V., Demeter, M., Schneider, B., Hartmann, D., Neumann, M., Exchange Sphtting of the Cr, Fe and Mn 3s XPS Spectra in Some Ternary Magnetic Semiconductor Sulphides , Solid State Commun., 114, 149-154 (2001) (Experimental, Crys. Stracture, Optical Prop., 24)... 

FIGURE 4 Total energy differences between divalent and trivalent elemental lanthanide metals (open circles) and their sulphides (solid circles). The dashed line shows the experimental values for the lanthanide metals. The calculated energy differences have been uniformly shifted upwards by 43 mRy to reproduce the valence transition pressure of 6 kbar in SmS. 

FIGURE 5 The energy differences between the divalent and trivalent valence states of the elemental lanthanides (open circles) and their sulphides (solid circles) versus the difference between the fractional numbers of itinerant f electrons in the two valence states. 

Debart A, Dupont L, Patrice R, Tarascon JM (2006) Reactivity of transition metal (Co, Ni, Cu) sulphides versus lithium the intriguing case of the copper sulphide. Solid State Sd... 

Mrowec S, Danielewski M, Stoklosa A, Defect structure and diffusion in nonstoichiometric ferrous sulphide . Solid State Ionics, 1980 1 287-309. 

Copper Il) sulphide, CuS. Black solid, Cu plus excess S or copper(II) salt plus H2S. Decomposes to copper(l) sulphide, CU2S, on heating. 

PPha, pyridine) organic groups (olefines, aromatic derivatives) and also form other derivatives, e.g. halides, hydrides, sulphides, metal cluster compounds Compounds containing clusters of metal atoms linked together by covalent (or co-ordinate) bands, metaldehyde, (C2H40) ( = 4 or 6). A solid crystalline substance, sublimes without melting at I12 1I5" C stable when pure it is readily formed when elhanal is left in the presence of a catalyst at low temperatures, but has unpredictable stability and will revert to the monomer, ft is used for slug control and as a fuel. 

Tin IV) sulphide, SnS2- Precipitated from Sn(IV) solution with H2S or Sn plus S under pressure. NH4CI, Sn, S heated gives a yellow solid (mosaic gold). Used as a pigment. 

These are ionic solids and can exist as the anhydrous salts (prepared by heating together sulphur with excess of the alkali metal) or as hydrates, for example Na2S.9HjO. Since hydrogen sulphide is a weak acid these salts are hydrolysed in water,... 

They are rapidly hydrolysed by water and the hydrolysis of solid aluminium sulphide can be used to prepare hydrogen sulphide ... 

These closely resemble the corresponding sulphides. The alkali metal selenides and tellurides are colourless solids, and are powerful reducing agents in aqueous solution, being oxidised by air to the elements selenium and tellurium respeetively (cf. the reducing power of the hydrides). 

If a solid sulphite is heated with zinc dust (or carbon) the sulphite is reduced to sulphide ... 

Cobalt U) sulphide is precipitated as a black solid by addition of sulphide ion to a solution of a cobalt(II) salt, in alkaline solution. 

Cadmiumdl) sulphide, CdS, is a canary-yellow solid, precipitated by addition of hydrogen sulphide (or sulphide ion) to an acid solution... 

Complexes of cadmium include, besides those already mentioned, a tetracyanocadmiate [Cd(CN)4] which in neutral solution is sufficiently unstable to allow precipitation of cadmium(II) sulphide by hydrogen sulphide. Octahedral [CdCl ] ions are known in the solid state, as, for example, K4CdCl5. 

These solutions are obtained by dissolving 40 g. of the solid in water so that the final volume of the cold solution is 100 ml. With pure sodium hydroxide, the alkaline solution should be quite clear and free from insoluble material. The sodium sulphide used is the crystalline Na,S, qHjO. 

Anhydrous sodium sulphide. The hydrated salt, NajS.QH O, is heated in a Pyrex distilling flask or retort in a stream of hydrogen or of nitrogen until water ceases to be evolved. The solid cake of anhydrous sodium sulphide is removed from the vessel with the aid of a copper wire hook or by other suitable means. No attempt should be made to fuse the sodium sulphide since at high temperatiues sodium sulphide is readily oxidised to sodium sulphate. 

Sulphoxides. These are usually solids of low m.p. They may be oxidised in glacial acetic acid solution by potassium permanganate to the corresponding sulphones, and reduced to the sulphides by boiling with tin or zinc and hydro chloric acid. 

It is known that Selenium catalyzes reaction of some dye reduction by Sulphide. On this basis spectrophotometric and test-techniques for Selenium determination are developed. Inefficient reproducibility and low sensitivity are their deficiencies. In the present work, solid-phase reagent on silica gel modified first with quaternary ammonium salt and then by Indigocarmine was proposed for Selenium(IV) test-determination. Optimal conditions for the Selenium determination by method of fixed concentration were found. The detection limit of Se(IV) is 10 ftg/L = 2 ng/sample). Calibration curve is linear in the range 50-400 ftg/L of Se(IV). The proposed method is successfully applied to the Selenium determination in multivitamins and bioadditions. 

The reaction of metals with gas mixtures such as CO/CO2 and SO2/O2 can lead to products in which the reaction of the oxygen potential in the gas mixture to form tire metal oxides is accompanied by the formation of carbon solutions or carbides in tire hrst case, and sulphide or sulphates in the second mixture. Since the most importairt aspects of this subject relate to tire performairce of materials in high temperature service, tire reactions are refeiTed to as hot corrosion reactions. These reactions frequendy result in the formation of a liquid as an intermediate phase, but are included here because dre solid products are usually rate-determining in dre coiTosion reactions. 

The production of copper from sulphide minerals is accomplished with a preliminary partial roast of die sulphides before reaction widr air in the liquid state, known as mattes, to form copper metal (conversion). The principal sources of copper are minerals such as chalcopyrite, CuFeSa and bornite CuaFeSa, and hence the conversion process must accomplish the preferential oxidation of non, in the form of FeO, before the copper metal appears. As mentioned before, tire FeO-SiOa liquid system is practically Raoultian, and so it is relatively easy to calculate the amount of iron oxidation which can be canned out to form this liquid slag as a function of the FeO/SiOa ratio before copper oxidation occurs. The liquid slag has a maximum mole fraction of FeO at the matte blowing temperatures of about 0.3, at solid silica saturation. 

These materials have been prepared by polymerisation of p-halothiophenoxide metal compounds both in the solid state and in solution. They have also been prepared by condensation of p-dichlorobenzene with elemental sulphur in the presence of sodium carbonate while the commercial polymers are said to be produced by the reaction of p-dichlorobenzene with sodium sulphide in a polar solvent. 

---