Barium bromide – Wikipedia
From Wikipedia, the free encyclopedia
Identifiers | |
---|---|
ChemSpider | |
ECHA InfoCard | 100.031.024 |
EC Number | |
UNII | |
|
|
|
|
Properties | |
BaBr2 (anhydrous)
BaBr2·2H2O (dihydrate) |
|
Molar mass | 297.14 g/mol |
Appearance | White solid |
Density | 4.78 g/cm3 (anhydrous) 3.58 g/cm3 (dihydrate) |
Melting point | 857 °C (1,575 °F; 1,130 K) |
Boiling point | 1,835 °C (3,335 °F; 2,108 K) |
92.2 g/100 mL (0°C) | |
-92.0·10−6 cm3/mol | |
Structure | |
orthorhombic, oP12 | |
Pnma, No. 62 | |
Thermochemistry | |
−181.1 kcal/mol | |
Hazards | |
Occupational safety and health (OHS/OSH): | |
Main hazards |
Toxic |
GHS labelling: | |
Warning | |
H302, H332 | |
P261, P264, P270, P271, P301+P312, P304+P312, P304+P340, P312, P330, P501 | |
NFPA 704 (fire diamond) |
|
Safety data sheet (SDS) | NIH BaBr |
Related compounds | |
Barium fluoride Barium chloride Barium iodide |
|
Beryllium bromide Magnesium bromide Calcium bromide Strontium bromide Radium bromide Lead bromide |
|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
Chemical compound
Barium bromide is the chemical compound with the formula BaBr2. It is ionic in nature.
Structure and properties[edit]
BaBr2 crystallizes in the lead chloride (cotunnite) motif, giving white orthorhombic crystals that are deliquescent.[1][2]
In aqueous solution BaBr2 behaves as a simple salt.
Solutions of barium bromide reacts with the sulfate salts to produce a solid precipitate of barium sulfate.
- BaBr2 + SO2−
4 → BaSO4 + 2 Br−
Similar reactions occur with oxalic acid, hydrofluoric acid, and phosphoric acid, giving solid precipitates of barium oxalate, fluoride, and phosphate, respectively.
Preparation[edit]
Barium bromide can be prepared by treating barium sulfide or barium carbonate with hydrobromic acid:
- BaS + 2 HBr → BaBr2 + H2S
- BaCO3 + 2 HBr → BaBr2 + CO2 + H2O
Barium bromide crystallizes from concentrated aqueous solution in its dihydrate , BaBr2·2H2O. Heating this dihydrate to 120 °C gives the anhydrous salt. [6]
Barium bromide is a precursor to chemicals used in photography and to other bromides.
Historically, barium bromide was used to purify radium in a process of fractional crystallization devised by Marie Curie. Since radium precipitates preferentially in a solution of barium bromide, the ratio of radium to barium in the precipitate would be higher than the ratio in the solution.[7]
Barium bromide, along with other water-soluble barium salts (e.g. barium chloride), is toxic. However, there is no conclusive data available on its hazards. [8]
In popular culture[edit]
The compound appears in the intro title card of Breaking Bad, where the title is replaced with “Br” and “Ba”, the symbols of bromine and barium, respectively.
References[edit]
- ^ a b Brackett, Elizabeth B.; Brackett, Thomas E.; Sass, Ronald L. (1963). “The Crystal Structures of Barium Chloride, Barium Bromide, and Barium Iodide”. J. Phys. Chem. 67 (10): 2132–2135. doi:10.1021/j100804a038.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. pp. 117–119. ISBN 978-0-08-037941-8.
- ^ “Information card for entry 1527183”. Crystallography Open Database. 1963. Retrieved 2021-03-26.
- ^ “ICSD 15706 : ICSD Structure : Ba Br2“. Cambridge Structural Database: Access Structures. Cambridge Crystallographic Data Centre. Retrieved 2021-03-26.
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 382. ISBN 978-0-08-037941-8.
- ^ Patnaik, Pradyot (2003), Handbook of Inorganic Chemical Compounds, McGraw-Hill Professional, pp. 81–82, ISBN 978-0-07-049439-8, retrieved 2007-12-03
- ^ Sime, Ruth Lewin (1996), Lise Meitner: A Life in Physics, University of California Press, p. 233, ISBN 978-0-520-20860-5, retrieved 2007-12-03
- ^ https://www.sigmaaldrich.com/MSDS/MSDS/DisplayMSDSPage.do?country=US&language=en&productNumber=413607&brand=ALDRICH
|
Recent Comments