Lithium bromide

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Lithium bromide
Identifiers
CAS number 7550-35-8 YesY
PubChem 82050
ChemSpider 74049 YesY
UNII 864G646I84 YesY
EC number 231-439-8
RTECS number OJ5755000
Jmol-3D images Image 1
Properties
Molecular formula LiBr
Molar mass 86.845(3) g/mol
Appearance White solid
hygroscopic
Density 3.464 g/cm3
Melting point

552 °C

Boiling point

1265 °C

Solubility in water 145 g/100 mL (4 °C)
166.7 g/100 mL (20 °C)
254 g/100 mL (90 °C)
Solubility soluble in methanol, ethanol, ether
slightly soluble in pyridine
Refractive index (nD) 1.784
Thermochemistry
Std enthalpy of
formation
ΔfHo298
-4.044 kJ/g
Hazards
EU Index Not listed
NFPA 704
NFPA 704.svg
0
2
0
Flash point not flammable
Related compounds
Other anions Lithium fluoride
Lithium chloride
Lithium iodide
Other cations Sodium bromide
Potassium bromide
Rubidium bromide
Caesium bromide
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Lithium bromide, or LiBr, is a chemical compound of lithium and bromine. Its extreme hygroscopic character makes LiBr useful as a desiccant in certain air conditioning systems.[1]

Contents

Production and properties [edit]

LiBr is prepared by treatment of lithium carbonate with hydrobromic acid. The salt forms several crystalline hydrates, unlike the other alkali metal bromides.[2] The anhydrous salt forms cubic crystals similar to common salt.

Lithium Hydroxide and Hydrobromic Acid (Aqueous solution of Hydrogen Bromide) will precipitate Lithium Bromide in the presence of water.

LiOH + HBr → LiBr + H2O

Uses [edit]

Lithium bromide is used in air-conditioning systems as desiccant.
Otherwise the salt is useful as a reagent in organic synthesis. For example it reversibly forms adducts with some pharmaceuticals.[1]

Medical applications [edit]

Lithium bromide was used as a sedative, beginning in the early 1900s, but it fell into disfavor in the 1940s when some heart patients died after using it as a salt substitute.[3]
Like lithium carbonate and lithium chloride, it was used as treatment for bipolar disorder.

Doses as low as 225 mg/day of LiBr can lead to bromism.

Hazards [edit]

Lithium salts are psychoactive and somewhat corrosive. When lithium bromide is dissolved into water, the reaction is very exothermic.

References [edit]

  1. ^ a b Ulrich Wietelmann, Richard J. Bauer "Lithium and Lithium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry 2005, Wiley-VCH: Weinheim.
  2. ^ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.
  3. ^ Bipolar disorder

External links [edit]