Bismuth fluoride, oxidation

Perhaps the most reactive compound of the group is BiFs- It reacts extremely vigorously with H2O to form O3, OF2 and a voluminous brown precipitate which is probably a hydrated bismuth(V) oxide fluoride. At room temperature BiFs reacts vigorously with iodine or sulfur above 50° it converts paraffin oil to fluorocarbons at 150° it fluorinates UF4 to UF and at 180° it converts Brs to BrFs and BrFs, and CI2 to CIF. 

The reason for the ultramicrochemical test was to establish whether the bismuth phosphate would carry the plutonium at the concentrations that would exist at the Hanford extraction plant. This test was necessary because it did not seem logical that tripositive bismuth should be so efficient in carrying tetrapositive plutonium. In subsequent months there was much skepticism on this point and the ultramicrochemists were forced to make repeated tests to prove this point. Thompson soon showed that Pu(Vl) was not carried by bismuth phosphate, thus establishing that an oxidation-reduction cycle would be feasible. All the various parts of the bismuth-phosphate oxidation-reduction procedure, bulk reduction via cross-over to a rare earth fluoride oxidation-reduction step and final isolation by precipitation of plutonium (IV) peroxide were tested at the Hanford concentrations of... 

The fluorides of the s- and p-block elements of the periods beyond the second are summarized in Table 7.1. The oxidizing power of fluorine produces numerous examples of hypervalency, in which the maximum valency is shown by the most stable compounds. The only exception to this statement is provided by the bismuth fluorides the hypervalent BiFj (linear polymer) is considerably less stable than the +3 compound. There are a few examples of the inert pair effect, but the fluorides with the group valency are the more stable. 

Complex fluorides (LiBiF6, and KBiF6) are known1 and they are weaker oxidizing agents than bismuth(V) fluoride itself. If parallels with potassium tetrafluorocobaltate(III) and co-balt(III) fluoride are valid (see Section 25.1.), then they will also be weaker fluorinating agents. 

The rate of oxidation of acetophenoximes with bismuth(V) fluoride in a mixture of hydrogen fluoride and perchloric acid follows first-order kinetics in both the oxime and Bi(V). The reaction is acid catalysed. A bridged outer-sphere mechanism, involving formation of an iminoxy radical, has been suggested.81... 

Beryllium chloride, 0221 Beryllium fluoride, 0223 Bis(l-chloroethylthallium chloride) oxide, 1586 Bismuth pentafluoride, 0227... 

Other ingredients that may be found in smokeless powders include camphor, carbazole, cresol, diethyleneglycoldinitrate (DEGDN), dimethylse-bacate, dinitrocresol, di-normal-propyl adipate, 2.4-dinitrodiphenylamine, PETN, TNT, RDX, acaroid resin, gum arabic, synthetic resins, aluminum, ammonium chlorate/oxalate/perchlorate, pentaerythritol dioleate, oxamide, lead carbonate/salicylate/stearate, magnesium oxide, sodium aluminum fluoride, sodium carbonate/bicarbonate, petrolatum, dioctylphthalate, stannic oxide, potassium cyrolate, triphenyl bismuth. 

The redistribution reaction in lead compounds is straightforward and there are no appreciable side reactions. It is normally carried out commercially in the liquid phase at substantially room temperature. However, a catalyst is required to effect the reaction with lead compounds. A number of catalysts have been patented, but the exact procedure as practiced commercially has never been revealed. Among the effective catalysts are activated alumina and other activated metal oxides, triethyllead chloride, triethyllead iodide, phosphorus trichloride, arsenic trichloride, bismuth trichloride, iron(III)chloride, zirconium(IV)-chloride, tin(IV)chloride, zinc chloride, zinc fluoride, mercury(II)chloride, boron trifluoride, aluminum chloride, aluminum bromide, dimethyl-aluminum chloride, and platinum(IV)chloride 43,70-72,79,80,97,117, 131,31s) A separate catalyst compound is not required for the exchange between R.jPb and R3PbX compounds however, this type of uncatalyzed exchange is rather slow. Again, the products are practically a random mixture. 

The white powder BiFg, like SbFg, is made from the oxide and HF with an excess of oxide, the oxide fluoride BiOF is formed. The trichloride, tribromide and tri-iodide of bismuth can all be made by direct combination. BiBrg is yellow and Bilg, black. The last is hydrolysed by hot water to bronze crystals of BiOL... 

Metathesis of triarylbismuth dichloride with a variety of metal salts such as fluoride, azide, cyanide, carboxylates and sulfonates has been used frequently for the synthesis of triarylbismuth(V) compounds of the type Ar Bi Y 2, where Y is the corresponding anionic group (Section 3.1.1). The reaction of triphenyl-bismuth dichloride with mercuric chloride in an alkaline medium leads to triphenylbismuthine, while treatment of triphenylbismuth dicyanide with mercuric oxide results in the formation of triphenylbismuthine oxide (Section... 

Masking can be achieved by precipitation, complex formation, oxidation-reduction, and kinetically. A combination of these techniques may be employed. For example, Cu " can be masked by reduction to Cu(I) with ascorbic acid and by complexation with I . Lead can be precipitated with sulfate when bismuth is to be titrated. Most masking is accomplished by selectively forming a stable, soluble complex. Hydroxide ion complexes aluminum ion [Al(OH)4 or AlOa"] so calcium can be titrated. Fluoride masks Sn(IV) in the titration of Sn(II). Ammonia complexes copper so it cannot be titrated with EDTA using murexide indicator. Metals can be titrated in the presence of Cr(III) because its EDTA chelate, although very stable, forms only slowly. 

BISMUTH (7440-69-9) Powder is a highly flammable solid. Reacts with strong acids and strong oxidizers chlorine, aluminum, fused ammonium nitrates bromine trifluoride chloric acid chlorine, halogens, iodine pentafluoride nitric acid perchloric acid and nitrosyl fluoride. Contact with fire releases bismuth oxide. 

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