Barium bromide
Identifiers | |
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10553-31-8 (anhydrous) 7791-28-8 (dihydrate) | |
3D model (Jmol) | Interactive image |
ChemSpider | 59728 |
ECHA InfoCard | 100.031.024 |
UNII | TI8NM689HW |
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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) | |
Structure | |
orthorhombic, oP12 | |
Pnma, No. 62 | |
Thermochemistry | |
Std enthalpy of formation (ΔfH |
−181.1 kcal/mol |
Hazards | |
EU classification (DSD) |
Harmful (Xn) |
R-phrases | R20, R22 |
S-phrases | S28[1] |
Related compounds | |
Other anions |
Barium fluoride Barium chloride Barium iodide |
Other cations |
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). | |
verify (what is ?) | |
Infobox references | |
Barium bromide is the chemical compound with the formula BaBr2. Like barium chloride, it dissolves well in water and is toxic in aqueous solution.
Structure and properties
BaBr2 crystallizes in a lead chloride motif, giving white orthorhombic crystals which are deliquescent.[2] In aqueous solution BaBr2 behaves as a simple salt.
Barium bromide reacts with the sulfate ion from sulfuric acid to produce a precipitate of barium sulfate.
Similar reactions occur with oxalic acid, hydrofluoric acid, and phosphoric acid.
Preparation
Barium bromide can be prepared from barium sulfide or barium carbonate via reaction with hydrobromic acid to give hydrated barium bromide. This happens over a short period of time
Barium bromide can be crystallized out from the solution in its dihydrate form, BaBr2·2H2O, which gives the anhydrous form upon heating to 120 °C.[3]
Uses
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.[4]
Safety
Barium bromide, along with other water-soluble barium salts, is toxic and can cause severe poisoning if ingested.
References
- ↑ https://fscimage.fishersci.com/msds/10358.htm
- ↑ Brackett, Elizabeth B.; Breackett, Thomas E.; Sass, Ronald L. (December), "The Crystal Structures of Barium Chloride, Barium Bromide, and Barium Iodide.", The Journal of Physical Chemistry (– Scholar search), 67 (published 1963), p. 2132, retrieved 2007-12-03 Check date values in:
|date=
(help) - ↑ Patnaik, Pradyot (2003), Handbook of Inorganic Chemical Compounds, McGraw-Hill Professional, pp. 81–82, ISBN 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 0-520-20860-9, retrieved 2007-12-03