Lithium chloride

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Lithium chloride
Lithium chloride
Lithium chloride
IUPAC name Lithium Chloride
Identifiers
CAS number [7447-41-8]
[404596-80-1]
PubChem 4933294
RTECS number OJ5950000
Properties
Molecular formula LiCl (anhydrous)
LiCl•3H2O (trihydrate)
Molar mass 42.394(4) gmol-1 (anhydrous)
96.440(5)gmol-1 (trihydrate)
Appearance white solid
Density 2.07 gcm-3 (anhydrous)
Melting point

605 °C (878 K)

Boiling point

>1300 °C (>1570 K)

Solubility in water 2.0 molL-1 (20 °C) (anhydrous)
Hazards
MSDS External MSDS
NFPA 704
0
1
0
 
R-phrases R22, R36, R37, R38
S-phrases S26, S36, S37, S39
Related compounds
Other anions Lithium fluoride
Lithium bromide
Lithium iodide
Other cations Sodium chloride
Potassium chloride
Rubidium chloride
Caesium chloride
Supplementary data page
Structure and
properties
n, εr, etc.
Thermodynamic
data
Phase behaviour
Solid, liquid, gas
Spectral data UV, IR, NMR, MS
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Lithium chloride is a chemical compound with the formula LiCl. The salt is a typical ionic compound, although the small size of the Li+ ion gives rise to properties not seen for other alkali metal chlorides, such as extraordinary solubility in polar solvents (83g/100 mL of water at 20 °C) and its hygroscopic properties.[1]

Contents

[edit] Chemical properties

The salt forms crystalline hydrates, unlike the other alkali metal chlorides.[2] Mono-, tri-, and pentahydrates are known.[3] It also absorbs up to four equivalents of ammonia. As with any other ionic chlorides, solutions of lithium chloride serves as a source of chloride ion, e.g. forming a precipitate upon treatment as silver nitrate:

LiCl + AgNO3 → AgCl + LiNO3

[edit] Preparation

Lithium chloride is produced by treatment of lithium carbonate with hydrochloric acid. It can in principle also be generated by the highly exothermic reaction of lithium metal with either chlorine or anhydrous hydrogen chloride gas. To minimize hydrolysis, anhydrous LiCl is prepared from the hydrate by heating with a stream of hydrogen chloride.

[edit] Uses

Lithium chloride is mainly used for the production of lithium metal by electrolysis of a LiCl/KCl melt at 600 °C. LiCl is also used as a brazing flux for aluminium in automobile parts. It is used as a desiccant for drying air streams.[1] In more specialized applications, lithium chloride finds some use in organic synthesis, e.g. as an additive in the Stille reaction. Also, in biochemical applications, it can be used to precipitate RNA from cellular extracts.[4]

[edit] Precautions

Lithium salts affects the central nervous system; see lithium pharmacology for more details. For a short time in the 1940s lithium chloride was manufactured as a substitute for salt, but this was prohibited after the toxic effects of the compound were recognized.[5][6][7]

[edit] References

  • Handbook of Chemistry and Physics, 71st edition, CRC Press, Ann Arbor, Michigan, 1990.
  • N. N. Greenwood, A. Earnshaw, Chemistry of the Elements, 2nd ed., Butterworth-Heinemann, Oxford, UK, 1997.
  • R. Vatassery, titration analysis of LiCl, sat'd in Ethanol by AgNO3 to precipitate AgCl(s). EP of this titration gives%Cl by mass.
  • H. Nechamkin, The Chemistry of the Elements, McGraw-Hill, New York, 1968.
  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. ^ Andreas Hönnerscheid, Jürgen Nuss, Claus Mühle, Martin Jansen "Die Kristallstrukturen der Monohydrate von Lithiumchlorid und Lithiumbromid" Zeitschrift für anorganische und allgemeine Chemie, 2003, volume 629, p. 312-316.doi:10.1002/zaac.200390049
  4. ^ Cathala, G., Savouret, J., Mendez, B., West, B.L., Karin, M., Martial, J.A., and Baxter, J.D. (1983). "A Method for Isolation of Intact, Translationally Active Ribonucleic Acid.". DNA 2 (4): 329-335. PMID 6198133. 
  5. ^ Talbott J. H. (1950). "Use of lithium salts as a substitute for sodium chloride.". Arch Med Interna. 85 (1): 1-10. PMID 15398859. 
  6. ^ L. W. Hanlon, M. Romaine, F. J. Gilroy. (1949). "Lithium Chloride as a Substitute for Sodium Chloride in the Diet". Journal of the American Medical Association 139 (11): 688-692. 
  7. ^ Case of trie Substitute Salt. TIME (28 Feb 1949).