Bromine pentafluoride
Encyclopedia
Bromine pentafluoride, Br
F5
, 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 silicate
s in the presence of bromine pentafluoride releases O2 for subsequent analysis. It is also used as an oxidizer in liquid rocket propellant
s and as a fluorinating agent in the processing of uranium
.
For the preparation of smaller amounts, potassium bromide
is used:
This route yields bromine pentafluoride almost completely free of trifluorides and other impurities.
and hydrofluoric acid
:
It is an extremely effective fluorinating agent, converting most uranium compounds to the hexafluoride at room temperature.
and hepatosis.
It may spontaneously ignite or explode upon contact with organic materials or metals in powdered form.
Bromine
Bromine ") is a chemical element with the symbol Br, an atomic number of 35, and an atomic mass of 79.904. It is in the halogen element group. The element was isolated independently by two chemists, Carl Jacob Löwig and Antoine Jerome Balard, in 1825–1826...
F5
Fluorine
Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic...
, is an interhalogen compound
Interhalogen
The halogens react with each other to form interhalogen compounds.The general formula of most interhalogen compounds is XYn, where n = 1, 3, 5 or 7, and X is the less electronegative of the two halogens...
and a fluoride
Fluoride
Fluoride is the anion F−, the reduced form of fluorine when as an ion and when bonded to another element. Both organofluorine compounds and inorganic fluorine containing compounds are called fluorides. Fluoride, like other halides, is a monovalent ion . Its compounds often have properties that are...
of bromine
Bromine
Bromine ") is a chemical element with the symbol Br, an atomic number of 35, and an atomic mass of 79.904. It is in the halogen element group. The element was isolated independently by two chemists, Carl Jacob Löwig and Antoine Jerome Balard, in 1825–1826...
. It is a strong fluorination reagent.
It melts at −61.30 °C and boils at 40.25 °C. BrF5 finds use in oxygen
Isotopes of oxygen
There are three stable isotopes of oxygen that lead to oxygen having a standard atomic mass of 15.9994 u. 17 radioactive isotopes have also been characterized, with mass numbers from 12O to 28O, all short-lived, with the longest-lived being 15O with a half-life of 122.24 seconds...
isotope analysis
Isotope analysis
Isotope analysis is the identification of isotopic signature, the distribution of certain stable isotopes and chemical elements within chemical compounds. This can be applied to a food web to make it possible to draw direct inferences regarding diet, trophic level, and subsistence...
. Laser ablation
Laser ablation
Laser ablation is the process of removing material from a solid surface by irradiating it with a laser beam. At low laser flux, the material is heated by the absorbed laser energy and evaporates or sublimates. At high laser flux, the material is typically converted to a plasma...
of solid silicate
Silicate
A silicate is a compound containing a silicon bearing anion. The great majority of silicates are oxides, but hexafluorosilicate and other anions are also included. This article focuses mainly on the Si-O anions. Silicates comprise the majority of the earth's crust, as well as the other...
s in the presence of bromine pentafluoride releases O2 for subsequent analysis. It is also used as an oxidizer in liquid rocket propellant
Rocket propellant
Rocket propellant is mass that is stored in some form of propellant tank, prior to being used as the propulsive mass that is ejected from a rocket engine in the form of a fluid jet to produce thrust. A fuel propellant is often burned with an oxidizer propellant to produce large volumes of very hot...
s and as a fluorinating agent in the processing of uranium
Uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...
.
Preparation
Bromine pentafluoride was first prepared in 1931 by the direct reaction of bromine with fluorine. 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
Potassium bromide
Potassium bromide is a salt, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries, with over-the-counter use extending to 1975 in the United States. Its action is due to the bromide ion...
is used:
- KBr + 3 F2 → KF + BrF5
This route yields bromine pentafluoride almost completely free of trifluorides and other impurities.
Reactions
Bromine pentafluoride reacts explosively with water by reaction, forming bromic acidBromic acid
Bromic acid, also known as hydrogen bromate, is an oxoacid that only exists in aqueous solution. It is a colorless solution that turns yellow at room temperature as it decomposes to bromine. Bromic acid and bromates are powerful oxidizing agents and are common ingredients in Belousov-Zhabotinsky...
and hydrofluoric acid
Hydrofluoric acid
Hydrofluoric acid is a solution of hydrogen fluoride in water. It is a valued source of fluorine and is the precursor to numerous pharmaceuticals such as fluoxetine and diverse materials such as PTFE ....
:
- 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 nephrosisNephrosis
Nephrosis refers to a non-inflammatory nephropathy.It should not be confused with nephritis, where inflammation is implied. However, some sources equate nephrosis with nephropathy.It can also be used to indicate an emphasis on the renal tubule....
and hepatosis.
It may spontaneously ignite or explode upon contact with organic materials or metals in powdered form.