Antimony acids

Boiling solutions of alkaline hydroxids convert it into antimonie acid.- 

Antimony pentoxid—Antimonie anJiydrid—Sb Os—320— is obtained by heating metantinionic acid to dull redness. It is an amorphous, tastelessj odorless, pale lemon-yellow colored solid very sparingly soluble in water and in acids. At a red heat it is-decomposed into Sb 0 and O. 

Antimony antimoniate—Intermediate oxid—Diantimonie te-troxid—SbjOi—304—occurs in nature, and is formed when the-oxids or hydrates of Sb are strongly heated, or when the lower stages of oxidation or the sulflds are oxidized by H2iO , or by fusion with sodium nitrate. It is insoluble in HaO but is decomposed by HCl, hydropotassie tartrate, and potash. 

Antimony Acids.—The normal antimonous acid, HsSbOs, corresponding to HjPOj, is unknown but the series of antimonie acids ortho—HaSbO, pyro—HiSbaOi, andmeta—HSbOs, is complete, either in the form of salts, or in that of the free acids. There also exists, in its sodium salt, a derivative of the lacking-antimonous acid metantimonous acid, HSbOa. 

The compound sometimes used in medicine under the name washed diaphoretic antimony is potassium metantimonate, united -with an excess of the pentoxid 2KSbOi, SbaO . The hydro-potassio pyroantimonate, KjHjSbj07,6Aq is a valuable reagent for the sodium compounds. It is obtained by calcining a mixture of one part of antimony with four parts of potassium nitrate, and fusing the product with its own weight of potassium carbonate. 

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Antimonious acid H3Sb03 and its salts are less well characterized but a few meta-antimonites and polyantimonites are known, e.g. NaSb02, NaSb305.H20 and Na2Sb407. The oxide itself finds extensive use as a flame retardant in fabrics, paper, paints, plastics, epoxy resins, adhesives and rubbers. The scale of industrial use can be gauged from the US statistics which indicate an annual consumption of Sb203 of some 10000 tonnes in that country. 

Antimonic acid, 3 59, 65 Antimonin (stibabenzene), 3 72 Antimonious acid, 3 43 Antimonite, 3 43... 

Sulphur trioxide similarly causes an increase in the conductivity of solutions of AsF5 in HS08F (Gillespie et al., 1969). Presumably acids such as H[AsF2(S03F)]4 are formed but they appear to be somewhat weaker than the corresponding antimony acids, just as AsFB forms a weaker acid in HS03F than SbFB. 

The action of stibine2 is similar to that of arsine, but only about 2 per cent, of the antimonious acid formed dissolves, the rest remaining in the precipitate ... 

Silica dust, aromatic and aliphatic hydroalkalis Silica, lead, cadmium, zinc, etc. 

M. Kogure, T. Sato, T. Tanaka, S. Yasujima, T. Suzuki and H. Ohya, Preparation of antimony acid cation exchange membranes by using metal alkoxide-gel method, Bull. Chem. Soc. Jpn., 1991, 1991, 1618 H. Ohya, R. Paterson, T. Nomura, S. McFadzean, T. Suzuki and M. Kogure, Properties of new inorganic membranes prepared by metal alkoxide methods. Part I A new permselective cation exchange membrane based on Si/Ta oxides, J. Membr. Sci., 1995, 105, 103-112. 

The mass spectral behaviour of proaporphine alkaloids has been analysed. Microcrystalloscopic determination of phenanthrene-isoquinolines using antimony acid complexes has been carried out. ... 

A number of new methodological developments in the analysis and purification of pilocarpine (22) hydrochloride have been published.A microcrystallo-scopic determination of imidazole derivatives using antimony acid complexes has been studied. 

Carbonates of the alkalies act like the alkaline hydrate they give rise to the formation of the oxide and sulphides of the alkalies, with evolution of carbonic acid secondary actions produce siilphantimon-ites, antimonites, and antimony sulphide. The solution of the sulphide is never complete, even when it is heated and, according to Terreil, carbonate of potassium does not help it. This has been demonsti-ated by Weppen and affirmed by Terreil. When a solution of sodium carbonate, to which the sulphide has been added, is being cooled, there are formed the sulphide, neutral and acid antimonites of sodium, and antimonious acid, constituting what is called Kermes mineral. ... 

Thio-antimonious Acids or Sulphantimonious Acids.—These acids are not known in the free state. In fact, they decompose immediately after their formation into hydrogen sulphide and sulphide of antimony. The complex anions of the acids are only stable in the presence of a neutial solution or in that of hydroxyl ions. The thio-antimonious acids are in part dissociated into the neutral and S" ions. 

The important thio-antimonious acids or siilph-antimonious acids are —... 

The following are some of the important salts formed from the thio-antimonious acids, according to Poiiget and Stauck —... 

The native minerals corresponding to some of these salts or to some other of the salts of thio-antimonious acids, are —... 

MM. Hallett and Btetthousis process —A natural oxide of antimony, or an ore in which the sulphide and the oxide are associated together, is used. The mineral is pulverised and is separated from the gangue by washing or by some mechanical device. The heavy portion thus obtained is calcined in a reverberatory furnace, and from it the sulphur is driven off as sulphuric acid. The residue consists mostly of antimonious acid, which, after being further powdered, is mixed with oil or varnish. The product may occasionally contain a little lead, copper, or iron, which has the effect of diminishing its whiteness. Hence it is mostly used for inferior painting. 

When oxide of antimony is heated, it absorbs oxygen, and when antimonic acid is heated, it loses oxygen, the product in both cases being the permanent antimonious acid. It is a white insoluble powder, very infusible and fixed in the fire. It forms salts, called antimonites, with bsises. 

Is formed by acting on the metal with strong nitric acid till it is converted into a white powder, which is hydrated antimonic acid. It is decomposed by a red heat, yielding water, oxygen, and antimonious acid. It forms salts, called antimoniates, wi bases. 

By the use of the diazo-reaction. In this connection Schmidt considers that antimony trioxide must act as antimonious acid when taking part in this reaction and may exist in tautomeric forms as shown by... 

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