Bromine pentafluoride
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| IUPAC name
Bromine pentafloride
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| Identifiers | |||
3D model (JSmol)
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| ChemSpider | |||
| ECHA InfoCard | 100.029.234 | ||
PubChem CID
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| RTECS number |
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CompTox Dashboard (EPA)
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| Properties | |||
| BrF5 | |||
| Molar mass | 174.894 g.mol−1 | ||
| Appearance | Pale yellow liquid | ||
| Density | 2.466 g/cm3 | ||
| Melting point | −61.30 °C | ||
| Boiling point | 40.25 °C | ||
| reacts | |||
| Structure | |||
| Square pyramidal | |||
| Hazards | |||
| NFPA 704 (fire diamond) | |||
| Flash point | Non-flammable | ||
| Related compounds | |||
Other anions
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Bromine monochloride | ||
Other cations
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Chlorine pentafluoride Iodine pentafluoride | ||
| Supplementary data page | |||
| Bromine pentafluoride (data page) | |||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Bromine pentafluoride, BrF5, is an interhalogen compound and a fluoride of bromine. It is a strong fluorination reagent.
It melts at −61.30 °C and boils at 40.25 °C. BrF5 finds use in oxygen isotope analysis. Laser ablation of solid silicates in the presence of bromine pentafluoride releases O2 for subsequent analysis.[1] It is also been tested as an oxidizer in liquid rocket propellants and is used as a fluorinating agent in the processing of uranium.
Preparation
Bromine pentafluoride was first prepared in 1931 by the direct reaction of bromine with fluorine.[2] This reaction is suitable for the preparation of large quantities, and is carried out at temperatures over 150 °C (302 °F) with an excess of fluorine:
- Br2 + 5 F2 → 2 BrF5
For the preparation of smaller amounts, potassium bromide is used:[2]
- KBr + 3 F2 → KF + BrF5
This route yields bromine pentafluoride almost completely free of trifluorides and other impurities.[2]
Reactions
Bromine pentafluoride reacts explosively with water, but when moderated by dilution with acetonitrile, it will form bromic acid and hydrofluoric acid, simple hydrolysis products:[3]
- BrF5 + 3 H2O → HBrO3 + 5 HF
It is an extremely effective fluorinating agent, converting most uranium compounds to the hexafluoride at room temperature.
Hazards
Bromine pentafluoride is severely corrosive to the skin, and its vapors are irritating to the eyes, skin, and mucous membranes. Exposure to 100 ppm for a few minutes is lethal to most experimental animals. Chronic exposure may cause nephrosis and hepatosis.[4]
It may spontaneously ignite or explode upon contact with organic materials or metals in powdered form.[4]
References
- ^ Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1016/0016-7037(63)90071-1, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with
|doi=10.1016/0016-7037(63)90071-1instead. - ^ a b c Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1021/ic50070a039, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with
|doi=10.1021/ic50070a039instead. - ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 834. ISBN 978-0-08-037941-8.
- ^ a b Patnaik, Pradyot (2007). A comprehensive guide to the hazardous properties of chemical substances (3rd ed.). Wiley-Interscience. p. 480. ISBN 0-471-71458-5.
External links
- WebBook page for BrF5
- International Chemical Safety Card 0974
- NIOSH Pocket Guide to Chemical Hazards. "#0065". National Institute for Occupational Safety and Health (NIOSH).
- National Pollutant Inventory - Fluoride and compounds fact sheet