Sodium pyroantimonate

Sodium hexakis(formato)molybdate, 3, 1235 Sodium hypochlorite alkene epoxidation manganese catalysts, 6,378 Sodium ions biology, 6, 559 selective binding biology, 6, 551 Sodium molybdate, 3, 1230 Sodium peroxoborate, 3,101 Sodium/potassium ATPase, 6, 555 vanadate inhibition, 3, 567 Sodium pump, 6, 555 mechanism, 6, 556 Sodium pyroantimonate, 3, 265 Sodium salts... 

Treatment with NaOH solution produces sodium pyroantimonate, Na(H20)e [Sb(OH)6]2 [10049-22-6] and sodium hexahydroxo antimonate(V), Na[Sb(OH)6] [12339-41-2]. Heating with metal oxides and carbonates produces various polyantimonate(V) derivatives. 

There is a marked structural difference between the phosphates and tlie antimonates. Thus sodium pyroantimonate. Na2H2Sb207- 5H20 contains the ion Sb(OH)g rather than Sb2C>74, and the magnesium compound (hydrated) which has a 12 1 ratio of oxygen to antimony, and would thus be a hexahydioxyantimonate, has the. (X-iav deteimined) stiuctuie [Mg(H20) l[Sb(0H)slj. 

Sodiuim bexakis(formato)molybdate, 1235 Sodium complexes crown ethers, 37 Sodium molybdate, 1230 Sodium peroxoborate, 101 Sodium/potassium ATPase vanadate inhibition, 567 Sodium pyroantimonate, 265 Sodium tetrahydroborate, 101... 

Figure. 7 Followsheet of sodium pyroantimonate produced by air oxidation from jamesonite...

In order to overcomne the disadvantages of the traditional smelting process the method of air oxidation was put forward to produce sodium proantimonate. Sodium pyroantimonate is... 

Mild acidification of molybdate-phosphate solutions yielded the colorless [P2Mos023]"6 anion, isolated as the sodium salt48,49 The heteropoly acid containing pentavalent antimony, H3[SbMo12O40] 48 H20, was reported to have been prepared by refluxing M/20 molybdic acid with M/75 potassium pyroantimonates°), however, more work is necessary to elucidate to exact nature of molybdenum heteropoly compounds containing antimony. 

Potassium Pyroantimonate TS Dissolve 2 g of potassium pyroantimonate in 95 mL of hot water. Cool quickly, and add a solution containing 2.5 g of potassium hydroxide in 50 mL of water and 1 mL of an 8.5 100 solution of sodium hydroxide. Allow to stand for 24 h, filter, and dilute with water to 150 mL. 

Sodium antimonate.—This substance is precipitated by the interaction of potassium antimonate and a concentrated solution of a sodium salt, its formation affording a means of testing for sodium. The white, amorphous salt may be regarded as the hydrated meta-antimonate, NaSb03,3 H20, or, since one molecule of water is expelled above 200° C., it may be considered a pyroantimonate, Na2H2Sb207,6H20.12 Its heat of formation from the elements is 346 4 Cal.13... 

Most salts of sodium are soluble in water, but the pyroantimonate, Na2H2Sb207, dissolves only to the extent of 1 part in 350 parts of boiling water. It is produced by addition of potassium pyroantimonate to a neutral or alkaline solution of a sodium salt. The double chloride with tin, and the double sulphite with platinum, Na6Pt(S03)4,7H20, are less soluble than the corresponding potassium salts. 

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. 

The classic reagent for qualitative and quantitative determination of sodium is uranyl acetate, which in the presence of sodium and a divalent metal cation gives a precipitate of NaM(U02)3(CH3C00)9, where M could be Mg, Zrf+, Co +, Ni + or others. However, since uranium is very poisonous and radioactive, tests based on these reagents have been replaced with tests based on sodium s reactivity toward pyroantimonate and methoxyphenylacetic. 

This salt has a tendency of forming rather stable super-saturated solutions, and this is the reason the test solution has to be cooled down and precipitation initiated by rubbing with a glass rod. For the same reason sodium hydroxide is added to the potassium pyroantimonate solution R in the reagent preparation so that saturation is almost reached. Both precautions are necessary to achieve a sufficient sensitivity ... 

The second purpose is to reveal the presence of cations that would otherwise give a false positive reaction by precipitating them as carbonates. Calcium is an example of such a cation. This first step has been the object of some debate since it has been observed that it is obviously possible to perform the pyroantimonate precipitation on a substance even though addition of carbonate has been omitted. The success of the test will, however, depend on the absence of, for example, calcium. Sodium s close neighbor in the alkali metal group, lithium, is claimed to give a false positive reaction. ... 

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