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| Names | |
|---|---|
| IUPAC name Strontium bromide | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider |
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| ECHA InfoCard | 100.030.868 |
| EC Number |
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| UNII | |
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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 inethanol Insoluble indiethyl ether |
| −86.6·10−6 cm3/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 | |
Otheranions | |
Othercations | |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Strontium bromide is achemical compound with a formulaSrBr2. At room temperature it is a white, odourless, crystalline powder. Strontium bromide imparts a bright red colour in aflame test, showing the presence of strontium ions. It is used inflares and also has some pharmaceutical uses.
SrBr2 can be prepared fromstrontium hydroxide andhydrobromic acid.
Alternativelystrontium carbonate can also be used asstrontium source.
These reactions givehexahydrate of strontium bromide (SrBr2·6H2O), which decomposes to dihydrate (SrBr2·2H2O) at 89 °C. At 180 °CanhydrousSrBr2 is obtained.[2]
At room temperature, strontium bromide adopts acrystal structure with atetragonalunit cell andspace groupP4/n. This structure is referred to as α-SrBr2 and isisostructural withEuBr2 andUSe2. The compound's structure was initially erroneously interpreted as being of thePbCl2 type,[3] but this was later corrected.[4][1]
Around 920 K (650 °C), α-SrBr2 undergoes afirst-order solid-solidphase transition to a much less ordered phase, β-SrBr2, which adopts the cubicfluorite structure. The beta phase of strontium bromide has a much higherionic conductivity of about 1 S/cm, comparable to that of moltenSrBr2, due to extensive disorder in thebromidesublattice.[1] Strontium bromide melts at 930 K (657 °C).
