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| Names | |
|---|---|
| IUPAC name
Strontium bromide | |
| Identifiers | |
3D model (JSmol) |
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| ChemSpider |
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| ECHA InfoCard | 100.030.868 
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| EC Number |
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PubChem CID |
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| UNII | |
CompTox Dashboard (EPA) |
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| Properties | |
| SrBr2 | |
| Molar mass | 247.428 g/mol (anhydrous) 355.53 g/mol (hexahydrate) |
| Appearance | white crystalline powder |
| Density | 4.216 g/cm3 (anhydrous) 2.386 g/cm3 (hexahydrate) |
| Melting point | 643 °C (1,189 °F; 916 K) |
| Boiling point | 2,146 °C (3,895 °F; 2,419 K) |
| 107 g/100 mL | |
| Solubility | Soluble in ethanol Insoluble in diethyl ether |
| −86.6·10−6cm3/mol | |
| Structure[1] | |
| Tetragonal | |
| P4/n (No. 85) | |
a = 1160.42 pm, c = 713.06 pm | |
Formula units (Z) |
10 |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards |
Corrosive |
| NFPA 704 (fire diamond) | |
| Related compounds | |
Other anions |
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Other cations |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
Strontium bromide is a chemical compound with a formula SrBr2. At room temperature it is a white, odourless, crystalline powder. Strontium bromide imparts a bright red colour in a flame test, showing the presence of strontium ions. It is used in flares and also has some pharmaceutical uses.
SrBr2 can be prepared from strontium hydroxide and hydrobromic acid.
Alternatively strontium carbonate can also be used as strontium source.
These reactions give hexahydrate of strontium bromide (SrBr2·6H2O), which decomposes to dihydrate (SrBr2·2H2O) at 89 °C. At 180 °C anhydrous SrBr2 is obtained.[2]
At room temperature, strontium bromide adopts a crystal structure with a tetragonal unit cell and space group P4/n. This structure is referred to as α-SrBr2 and is isostructural with EuBr2 and USe2. The compound's structure was initially erroneously interpreted as being of the PbCl2 type,[3] but this was later corrected.[4][1]
Around 920 K (650 °C), α-SrBr2 undergoes a first-order solid-solid phase transition to a much less ordered phase, β-SrBr2, which adopts the cubic fluorite structure. The beta phase of strontium bromide has a much higher ionic conductivity of about 1 S/cm, comparable to that of molten SrBr2, due to extensive disorder in the bromide sublattice.[1] Strontium bromide melts at 930 K (657 °C).
