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Thiotungstates

Thiosulfate-fixing solutions, 19 213 Thiosulfate titration, of iodine, 14 367, 368 Thiosulfuric acid, 23 669 Thiotungstates, 25 385 Thiourea, 12 690... [Pg.946]

Although thermodynamically possible, the slower rate of substitution of the tungsten(VI) species results in the formation of only a small amount of the corresponding thiotungstate ion, provided that the conditioning period with sulfide ion is controlled. Molybdenum trisulfide is then quantitatively precipitated by the decomposition of the thio salt by the slow addition of sulfuric acid to a pH value of between 2 and 3 ... [Pg.828]

Tungsten trisulfide [12125-19-8], WS3, is a chocolate-brown powder, slighdy soluble in cold water, but readily forming a colloidal solution in hot water. It is prepared by treating an alkah-metal thiotungstate with HC1 (52). Tungsten trisulfide is soluble in alkali carbonates and hydroxides. [Pg.290]

Ammonium sulphide solution no precipitate, but if the solution is afterwards acidified with dilute hydrochloric acid, a brown precipitate of tungsten trisulphide, WS3, is produced. The precipitate dissolves in ammonium sulphide solution forming a thiotungstate ion, WS4. ... [Pg.510]

Normal ammonium thiotungstate, (NH4)3WS4, is prepared by the prolonged action of hydrogen sulphide on a dilute solution of ammonium... [Pg.247]

Xnmuil sodium ihiofungstate. XajWSj, is prepared by similar reactions to the above. The crystals are very hygroscopic, and are exceedingly soluble in water. The solutions of normal thiotungstates are not precipitated by zinc sulphate. Sodium tliiotungstate is soluble in alcohol. [Pg.248]

Thiotungstates of calcium, stroiifiurn, and barium ha% e been prepared by tlie action of hydrogen sulphide on suspensions of the corresponding tungstates, whereby yellow solutions were obtained from which the thiotungstates could be crystallised. [Pg.248]

PR It can only be produced indirectly by decomposing sodium thiotungstate with hot sulfuric or hydrochloric acid. [Pg.166]

Several thiosalt precursors such as ammonium thiotungstate (NH4)2WS4 (known as ATT) and tetraalkylammonium thiotungstates (NR4)2WS4 were also used to synthesize WS2 (29). Besides, ammonium thiomolybdate (NH4)2MoS4 (known as ATM) and tetraalkylammonium thiomolybdates (NR4)2MoS4 were also used to obtain M0S2. [Pg.1551]

See other pages where Thiotungstates is mentioned: [Pg.395]    [Pg.395]    [Pg.290]    [Pg.290]    [Pg.169]    [Pg.982]    [Pg.559]    [Pg.568]    [Pg.1100]    [Pg.220]    [Pg.246]    [Pg.66]    [Pg.86]    [Pg.90]    [Pg.90]    [Pg.90]    [Pg.18]    [Pg.28]    [Pg.290]    [Pg.926]    [Pg.246]    [Pg.247]    [Pg.627]    [Pg.174]    [Pg.408]    [Pg.282]    [Pg.282]    [Pg.10]    [Pg.1205]    [Pg.1214]    [Pg.1746]    [Pg.2821]   
See also in sourсe #XX -- [ Pg.926 ]

See also in sourсe #XX -- [ Pg.247 ]



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Ammonium thiotungstate

Ammonium thiotungstates

Thiotungstates preparation

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