Sodium bromide
 |
This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (November 2010) |
| Sodium bromide | |
|---|---|
 |
|
 |
|
|
Sodium bromide |
|
| Identifiers | |
| CAS number | 7647-15-6  , 13466-08-5 (dihydrate) |
| PubChem | 253881 |
| ChemSpider | 22712 |
| UNII | LC1V549NOM |
| ChEMBL | CHEMBL1644694  |
| RTECS number | VZ3150000 |
| Jmol-3D images | Image 1 |
|
|
|
|
| Properties | |
| Molecular formula | NaBr |
| Molar mass | 102.894 g/mol |
| Appearance | White powder |
| Density | 3.21 g/cm3 (anhydrous) 2.18 g/cm3 (dihydrate) |
| Melting point |
747 °C (anhydrous) |
| Boiling point |
1396 °C |
| Solubility in water | 90.5 g/100 mL (20 °C) 121.0 g/100 mL (100 °C) |
| Solubility in methanol | 16.7 g/100mL |
| Refractive index (nD) | 1.6459 |
| Thermochemistry | |
| Std enthalpy of formation ΔfH |
−360 kJ·mol−1[1] |
| Standard molar entropy S |
84 J·mol−1·K−1[1] |
| Hazards | |
| MSDS | External MSDS[dead link] |
| EU Index | Not listed |
| Flash point | 800 °C |
| LD50 | 3500 mg/kg |
| Related compounds | |
| Other anions | Sodium fluoride Sodium chloride Sodium iodide |
| Other cations | Lithium bromide Potassium bromide Rubidium bromide Caesium bromide |
 (verify) (what is:  / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
|
| Infobox references |
Sodium bromide is an inorganic compound with the formula NaBr. It is a high-melting white, crystalline solid that resembles sodium chloride. It is a widely used source of the bromide ion and has many applications.[2]
Contents |
[edit] Synthesis, structure, reactions
NaBr crystallizes in the same cubic motif as NaCl, NaF and NaI. It is produced by treating sodium hydroxide with hydrogen bromide. The anhydrous salt crystallizes above 50.7 °C.[2]
Sodium bromide can be used as a source of the chemical element bromine. This can be accomplished by treating an aqueous solution of NaBr with chlorine gas:
- 2 NaBr + Cl2 → Br2 + 2 NaCl
[edit] Applications
Sodium bromide is the most useful inorganic bromide in industry.[2]
[edit] Medicine
Also known as Sedoneural, sodium bromide has been used as a hypnotic, anticonvulsant, and sedative in medicine , widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries. Its action is due to the bromide ion, and for this reason potassium bromide is equally effective.[3]
[edit] Preparation of other bromine compounds
Sodium bromide is widely used for the preparation of other bromides in organic synthesis and other areas. It is a source of the bromide nucleophile to convert alkyl chlorides to more reactive alkyl bromides by the Finkelstein reaction:
- NaBr + RCl → RBr + NaCl (R = alkyl)
Once a large need in photography, but now shrinking, the photosensitive salt silver bromide is prepared using NaBr.
[edit] Disinfectant
NaBr is used in conjunction with chlorine as a disinfectant for swimming pools.
[edit] Petroleum industry
Sodium bromide is used to prepare dense fluids used in oil wells.
[edit] Safety
NaBr has a very low toxicity with an oral LD50 estimated at 5 g/kg for rats.
[edit] References
- ^ a b Zumdahl, Steven S. (2009). Chemical Principles 6th Ed.. Houghton Mifflin Company. p. A23. ISBN 061894690X.
- ^ a b c Michael J. Dagani, Henry J. Barda, Theodore J. Benya, David C. Sanders "Bromine Compounds" in Ullmann's Encyclopedia of Industrial Chemistry" Wiley-VCH, Weinheim, 2000.doi:10.1002/14356007.a04_405
- ^ Bromide
