Английская Википедия:Bromine trifluoride

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Шаблон:Chembox

Bromine trifluoride is an interhalogen compound with the formula BrF3. At room temperature, it is a straw-coloured liquid with a pungent odor[1] which decomposes violently on contact with water and organic compounds. It is a powerful fluorinating agent and an ionizing inorganic solvent. It is used to produce uranium hexafluoride (UF6) in the processing and reprocessing of nuclear fuel.[2]

Synthesis

Bromine trifluoride was first described by Paul Lebeau in 1906, who obtained the material by the reaction of bromine with fluorine at 20 °C:[3]

Шаблон:Chem2

The disproportionation of bromine monofluoride also gives bromine trifluoride:[1]

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Structure

Like ClF3 and IF3, the BrF3 molecule is T-shaped and planar. In the VSEPR formalism, the bromine center is assigned two electron pairs. The distance from the bromine each axial fluorine is 1.81 Å and to the equatorial fluorine is 1.72 Å. The angle between an axial fluorine and the equatorial fluorine is slightly smaller than 90° — the 86.2° angle observed is due to the repulsion generated by the electron pairs being greater than that of the Br-F bonds.[4][5]

Chemical properties

In a highly exothermic reaction, BrF3 reacts with water to form hydrobromic acid and hydrofluoric acid:

Шаблон:Chem2

BrF3 is a fluorinating agent, but less reactive than ClF3.[6] Already at -196 °C, it reacts with acetonitrile to give 1,1,1-trifluoroethane.[7]

Шаблон:Chem2 + Шаблон:Frac Br2 + Шаблон:Frac N2

The liquid is conducting, owing to autoionisation:[2]

Шаблон:Chem2

Fluoride salts dissolve readily in BrF3 forming tetrafluorobromate:[2]

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It reacts as a fluoride donor:[8]

Шаблон:Chem2

References

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External links

Шаблон:Bromine compounds Шаблон:Fluorine compounds