3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||86.845 g/mol|
|Appearance||White hygroscopic solid|
|Melting point||550 °C (1,022 °F; 823 K)|
|Boiling point||1,300 °C (2,370 °F; 1,570 K)|
|143 g/100 mL (0 °C) |
166.7 g/100 mL (20 °C)
266 g/100 mL (100 °C)
|Solubility||soluble in methanol, ethanol, ether, acetone |
slightly soluble in pyridine
Refractive index (nD)
|1.7843 (589 nm)|
|Cubic, Pearson symbol cF8, No. 225|
a = 0.5496 nm
|74.3 J/mol K|
Std enthalpy of
Gibbs free energy (ΔfG˚)
|H315, H317, H319|
|NFPA 704 (fire diamond)|
|Lethal dose or concentration (LD, LC):|
LD50 (median dose)
|1800 mg/kg (oral, rat)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
what is ?)(
Lithium bromide (LiBr) is a chemical compound of lithium and bromine. Its extreme hygroscopic character makes LiBr useful as a desiccant in certain air conditioning systems.
LiBr is prepared by treating an aqueous suspension of lithium carbonate with hydrobromic acid or by reacting lithium hydroxide with bromine. The salt forms several crystalline hydrates, unlike the other alkali metal bromides. The anhydrous salt forms cubic crystals similar to common salt (sodium chloride).
Lithium hydroxide and hydrobromic acid (aqueous solution of hydrogen bromide) will precipitate lithium bromide in the presence of water.
A 50–60% aqueous solution of lithium bromide is used in air-conditioning systems as desiccant. It is also used as a salt in absorption chilling along with water (see absorption refrigerator). Solid LiBr is a useful reagent in organic synthesis. It is included into oxidation and hydroformylation catalysts; it is also used for deprotonation and dehydration of organic compounds containing acidic protons, and for the purification of steroids and prostaglandins.
Lithium bromide was used as a sedative beginning in the early 1900s, but it fell into disfavor in the 1940s as newer sedatives became available and when some heart patients died after using the salt substitute lithium chloride. Like lithium carbonate and lithium chloride, it was used as treatment for bipolar disorder.
Lithium salts are psychoactive and somewhat corrosive. Heat is quickly generated when lithium bromide is dissolved into water because it has a negative enthalpy of solution.