Sodium bromide

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Sodium bromide
Sodium bromide sample watchglass.jpg
Sample of sodium bromide
Names
IUPAC name
Sodium bromide
Preferred IUPAC name
Sodium bromide
Properties
NaBr
Molar mass 102.89 g/mol
Appearance White solid
Odor Odorless
Density 3.21 g/cm3 (anhydrous)
2.18 g/cm3 (dihydrate)
Melting point anhydrous
747 °C (1,377 °F; 1,020 K)
dihydrate
36 °C (97 °F; 309 K) (decomposes)
Boiling point 1,390 °C (2,530 °F; 1,660 K)
71.35 g/100 ml (−20 °C)
79.52 g/100 ml (0 °C)
94.32 g/100 ml (25 °C)
104.9 g/100 ml (40 °C)
116.2 g/100 ml (100 °C)
Solubility Soluble in liq. ammonia, formic acid, hydrazine, pyridine, liq. SO2
Slightly soluble in ethanol
Insoluble in acetone, acetonitrile
Solubility in dimethylformamide 3.2 g/100 g (10.3 °C)
Solubility in ethanol 2.45 g/100 g (0 °C)
2.32 g/100 g (20 °C)
2.29 g/100 g (30 °C)
2.35 g/100 g (70 °C)
Solubility in formic acid 19.3 g/100 g (18 °C)
19.4 g/100 g (25 °C)
Solubility in glycerol 38.7 g/100 g (20 °C)
Solubility in methanol 17.3 g/100 g (0 °C)
16.8 g/100 g (20 °C)
16.1 g/100 g (40 °C)
15.3 g/100 g (60 °C)
Vapor pressure ~0 mmHg
Acidity (pKa) 7
Thermochemistry
86.82 J·mol-1·K-1
−361.41 kJ/mol
Hazards
Safety data sheet Sigma-Aldrich
Flash point Non-flammable
Lethal dose or concentration (LD, LC):
3.500 mg/kg (rat, oral)
Related compounds
Related compounds
Potassium bromide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Sodium bromide is an inorganic compound with the formula NaBr.

Properties

Chemical

Sodium bromide will liberate free bromine if chlorine or an acid and oxidizer is used.

2 NaBr + Cl2 → 2 NaCl + Br2
2 KBr + 2 HCl + H2O2 → 2 KCl + Br2 + 2 H2O

Oxone will also achieve the same result.

Physical

Sodium bromide is a colorless white solid, soluble in water.

Availability

Sodium bromide is sold as brominating tablets at pool stores as an alternative to chlorine.

Can also be bought online or from lab suppliers.

Preparation

Can be prepared by neutralizing sodium hydroxide with hydrobromic acid.

NaOH + HBr → NaBr + H2O

Another route is to neutralize bromine with sodium thiosulfate or metabisulfite.

Projects

Handling

Safety

NaBr has a very low toxicity with an oral LD50 estimated at 3.5 g/kg for rats.

Storage

Sodium bromide is best kept in closed bottles.

Disposal

Can be poured down the drain.

References

Relevant Sciencemadness threads