Sodium bromide
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| Names | |
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| IUPAC name
Sodium bromide
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| Identifiers | |
| ECHA InfoCard | 100.028.727 |
PubChem CID
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| RTECS number |
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CompTox Dashboard (EPA)
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| Properties | |
| 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) 36 °C (dihydrate) |
| Boiling point | 1396 °C |
| 73.3 g/100 mL (20 °C) 116.0 g/100 mL (50 °C) | |
| Solubility in methanol | 16.7 g/100mL |
Refractive index (nD)
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1.6459 |
| Hazards | |
| Flash point | 800 °C |
| Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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3500 mg/kg |
| Related compounds | |
Other anions
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Sodium fluoride Sodium chloride Sodium iodide |
Other cations
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Lithium bromide Potassium bromide Rubidium bromide Caesium bromide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Sodium bromide, also known as sedoneural[1] is a salt with the formula NaBr, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries. Its action is due to the bromide ion (potassium bromide is equally effective).[2] It is a high-melting white, crystalline solid that resembles sodium chloride. It is a widely used source of the bromide ion.
Principal chemical reactions
NaBr is used in organic synthesis as a source of the bromide nucleophile to convert alkyl chlorides to more reactive alkyl bromides by the Finkelstein reaction.
- NaBr + RCl → RBr + NaCl
Sodium bromide can be used as a source of the chemical element bromine. This can be accomplished by bubbling chlorine gas through an aqueous solution of NaBr. As a source of HBr, NaBr is treated with a strong, non-volatile acid:
- NaBr + H3PO4 → HBr + NaH2PO4
HBr can also be oxidized to Br2 using MnO2 or concentrated H2SO4.
Other applications
- as a hypnotic, anticonvulsant, and sedative in medicine. As a source of the bromide ion, which is pharmacologically active, it is equivalent to potassium bromide (see this article for more complete discussion of this topic).
- in photography
- to establish a bromide ion reserve in a bromine spa (hot tub) antimicrobial treatment regimen.
Safety
NaBr is harmful if swallowed or inhaled in large amounts, affecting the central nervous system, brain, and eyes (see potassium bromide). The chemical compound causes irritation to the skin, eyes and respiratory system.