Antimony antimonites

Antimony forms both a + 3 and a + 5 oxide. The + 3 oxide can be prepared by the direct combination of the elements or by the action of moderately concentrated nitric acid on antimony. It is an amphoteric oxide dissolving in alkalis to give antimonates(III) (for example sodium antimonite , NaSb02), and in some acids to form salts, for example with concentrated hydrochloric acid the trichloride, SbCl3, is formed. 

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... 

Antimony trioxide is an amphoteric oxide, exhibiting both acidic and basic behavior. It dissolves in strong acids forming antimony salts e.g., reacts with aqueous hydrofluoric acid to form antimony trifluoride, SbFs. It reacts with strong alkalies to form antimonites, such as sodium or potassium anti-monites, NasSbOs or K38b03 ... 

Test a sodium antimonite solution with silver nitrate. What precipitates What properties does antimony(III) exhibit in this reaction ... 

The hydroxide V(OH)3 is distinguished from the corresponding hydroxides of phosphorus, arsenic and antimony in that it is wholly basic. It is insoluble in alkalis, so that there do not exist any compounds of vanadium which would correspond to the phosphites, arsenites, and antimonites, or to the ferrites, aluminates, and chromites. 

Hydrogen sulphide orange-red precipitate of antimony trisulphide, Sb2S3, from solutions which are not too acid. The precipitate is soluble in warm concentrated hydrochloric acid (distinction and method of separation from arsenic(III) sulphide and mercury(II) sulphide), in ammonium polysulphide (forming a thioantimonate), and in alkali hydroxide solutions (forming antimonite and thioantimonite). 

Sodium hydroxide or ammonia solution white precipitate of the hydrated antimony(III) oxide Sb203.xH20 soluble in concentrated (5m) solutions of caustic alkalis forming antimonites. 

Antimony trioxide, Sb O, is amphoteric. In addition to reacting with bases to form antimonites, it reacts with acids to form antimony salts, such as. antimony sulfate, Sb2(S04)3. The antimony ion Sb+ + + hydrolyzes readily to form the antimony I ion SbO. ... 

Antimony (Sb, at. mass 121.75) occurs in compounds in the oxidation states -III (stibine SbHs), III and V. The compounds of Sb(III) are the most stable. The Sb " ions hydrolyse at pH values as low as 1. The hydroxide Sb(OH)3 dissolves at pH 10 to form the antimonite ion, Sb02 . Antimony(V) is more acidic than Sb(III). Antimony (III and V) form sulphide-, halide-, tartrate-, and oxalate complexes. 

Antimony has geochemical behavior similar to arsenic, as it occurs most commonly in the +3 (antimonite) and +5 (antimonate) oxidation states and also tends to associate with sulfides in rocks, sediments, and soils. In soil solutions, the Sb and Sb oxidation states are stable under reducing and oxidizing conditions, respectively. 

Arylstibonic acids are formed when arenediazonium salts are decomposed by an alkali antimonite (Sb203 + alkali).519,520 The procedure can be varied by preparing a double salt, e.g., C6H5N2C1 SbCl3 by adding antimony trichloride in acid solution and decomposing the salt by sodium hydroxide solution. 

Direct chemical oxidation of the primary antimony ore antimonite (stibnite, SbjSj) by molecular oxygen is negligible and is effected mainly by specific autotrophic bacteria (Thiobacillus ferrooxidans at pH 2-6, and T thioparus subsp. antimon at pH 6-8)... 

HSbOo is obtained by decomposing tartrate of antimony and potassium with acetate or alkaline carbonate Long). This hydi-ate presents the character rather of a base than of an acid. Nevertheless it can give rise to the formation of antimonites. 

Antimonites.—They are salts formed from the acids derived from SkiOj, and are obtained from a solution of antimony hydroxides in alkaline liquor. The sodium salts derived from HSbOj are —... 

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. ... 

Aiiittmny gUmce, Sb.jS3 also known by the names gray antimony ore, stibiiite, or antimonite. It contains 7T4 per cout. of antimony and SS G per cent, of sulphur. 

The results of the experiments made by Borchers in 1886 prove that antimony was deposited in equal quantity both from the thio-antimoniate and thio-antimonite. If a sodium thio-antimonate solution be used, it is only necessary to add either sodium sulphide or sodium hydroxide, in such quantity that there is at least one atom of sodium for every atom of sulphur, in order to prevent the separation of sulphur at the anode. In other words, the action takes place best when three molecules of sodium sulphide (Na2S) are present for each molecule of antimony sulphide (SbjSj). 

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