Bromine pentafluoride

Bromine pentafluoride, BrF₅, is an interhalogen compound and a fluoride of bromine. It is a strong fluorinating agent.

Bromine pentafluoride

Ball-and-stick model of bromine pentafluoride Space-filling model of bromine pentafluoride
Names
IUPAC name Bromine pentafluoride
Identifiers
CAS Number	7789-30-2 Y
3D model (JSmol)	Interactive image
ChemSpider	23008 Y
ECHA InfoCard	100.029.234
EC Number	232-157-8
PubChem CID	24606
RTECS number	EF9350000
UNII	UPI6B7Y9UQ
UN number	1745
CompTox Dashboard (EPA)	DTXSID30894171
InChI InChI=1S/BrF5/c2-1(3,4,5)6 Y Key: XHVUVQAANZKEKF-UHFFFAOYSA-N Y InChI=1/BrF5/c2-1(3,4,5)6 Key: XHVUVQAANZKEKF-UHFFFAOYAC
SMILES FBr(F)(F)(F)F
Properties
Chemical formula	BrF5
Molar mass	174.894 g.mol−1
Appearance	Pale yellow liquid
Density	2.466 g/cm3
Melting point	−61.30 °C (−78.34 °F; 211.85 K)
Boiling point	40.25 °C (104.45 °F; 313.40 K)
Solubility in water	Reacts with water
Structure
Molecular shape	Square pyramidal
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Powerful oxidizer, corrosive, highly toxic, reacts violently with water to release HF[1]
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H271, H300+H310+H330, H314, H372
Precautionary statements	P210, P220, P221, P260, P264, P270, P271, P280, P283, P284, P301+P310, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P306+P360, P307+P311, P309+P311, P310, P314, P320, P321, P331, P363, P370+P378, P371+P380+P375, P403+P233, P405, P501
NFPA 704 (fire diamond)	4 0 4 W OX
Flash point	Non-flammable
NIOSH (US health exposure limits):
PEL (Permissible)	none[1]
REL (Recommended)	TWA 0.1 ppm (0.7 mg/m3)[1]
IDLH (Immediate danger)	N.D.[1]
Safety data sheet (SDS)	External MSDS[dead link‍]
Related compounds
Other anions	Bromine monochloride
Other cations	Chlorine pentafluoride Iodine pentafluoride
Related compounds	Bromine monofluoride Bromine trifluoride
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). Y verify (what is YN ?) Infobox references

BrF₅ finds use in oxygen isotope analysis. Laser ablation of solid silicates in the presence of BrF₅ releases O₂ for subsequent analysis.^[2] It has also been tested as an oxidizer in liquid rocket propellants and is used as a fluorinating agent in the processing of uranium.

Preparation

BrF₅ was first prepared in 1931 by the direct reaction of bromine and fluorine.^[3] This reaction is suitable for the preparation of large quantities,^{[citation needed]} 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:^[3]

KBr + 3 F₂ → KF + BrF₅

This route yields BrF₅ almost completely free of trifluorides and other impurities.^[3]

Reactions

BrF₅ reacts with water to form bromic acid and hydrofluoric acid:^[4]

BrF₅ + 3 H₂O → HBrO₃ + 5 HF

It is an extremely effective fluorinating agent, being able to convert most metals to their highest fluorides even at room temperature. With uranium and uranium compounds, it can be used to produce uranium hexafluoride:

5 U + 6 BrF₅ → 5 UF₆ + 3 Br₂

Hazards

BrF₅ reacts violently with water, and is severely corrosive and toxic. Its vapors are also extremely irritating to all parts of the human body, especially the skin, eyes and other mucous membranes. Like many other interhalogen compounds, it will release "smoke" containing acidic vapors if exposed to moist air, which comes from its reaction with the water in the air. Exposure to 100 ppm or more for more than one minute is lethal to most experimental animals. Chronic exposure may cause kidney damage and liver failure.^[5]

Additionally, BrF₅ is a strong oxidizing agent and may spontaneously ignite or explode upon contact with flammable substances such as organic materials and metal dust.^[5]

References

1. NIOSH Pocket Guide to Chemical Hazards. "#0065". National Institute for Occupational Safety and Health (NIOSH).
2. Clayton, R.; Mayeda, T. K. (1963). "The use of bromine pentafluoride in the extraction of oxygen from oxides and silicates for isotopic analysis". Geochimica et Cosmochimica Acta. 27 (1): 43–48. Bibcode:1963GeCoA..27...43C. doi:10.1016/0016-7037(63)90071-1.
3. Hyde, G. A.; Boudakian, M. M. (1968). "Synthesis routes to chlorine and bromine pentafluorides". Inorganic Chemistry. 7 (12): 2648–2649. doi:10.1021/ic50070a039.
4. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 834. ISBN 978-0-08-037941-8.
5. Patnaik, Pradyot (2007). A comprehensive guide to the hazardous properties of chemical substances (3rd ed.). Wiley-Interscience. p. 480. ISBN 978-0-471-71458-3.

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