Editing Lithium (section)

{{About|the chemical element|the use of lithium as a medication|Lithium (medication)|other uses|Lithium (disambiguation)}}
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'''Lithium''' (from {{langx|grc|λίθος}}, {{tlit|grc|líthos}}, {{gloss|stone}}) is a [[chemical element]]; it has [[chemical symbol|symbol]] '''Li''' and [[atomic number]]&nbsp;3. It is a soft, silvery-white [[alkali metal]]. Under [[standard temperature and pressure|standard conditions]], it is the least dense metal and the least dense solid element. Like all alkali metals, lithium is highly [[reactivity (chemistry)|reactive]] and flammable, and must be stored in vacuum, inert atmosphere, or inert liquid such as purified kerosene<ref>Spellman, F. R. (2023). ''The Science of Lithium''. CRC Press.</ref> or mineral oil. It exhibits a metallic [[luster (mineralogy)|luster]].  It [[corrosion|corrodes]] quickly in air to a dull silvery gray, then black tarnish. It does not occur freely in nature, but occurs mainly as [[pegmatite|pegmatitic]] minerals, which were once the main source of lithium. Due to its solubility as an ion, it is present in ocean water and is commonly obtained from [[brine]]s. Lithium metal is isolated [[electrolysis|electrolytically]] from a mixture of [[lithium chloride]] and [[potassium chloride]].

The [[Atomic nucleus|nucleus]] of the lithium atom verges on instability, since the two stable lithium [[isotope]]s found in nature have among the lowest [[Nuclear binding energy|binding energies]] per [[nucleon]] of all stable [[nuclide]]s. Because of its relative nuclear instability, lithium is less common in the [[Solar System]] than 25 of the first 32 chemical elements even though its nuclei are very light: it is an exception to the trend that heavier nuclei are less common.<ref name="Lodders2003">Numerical data from: {{cite journal |doi=10.1086/375492 |last=Lodders |first=Katharina |author-link=Katharina Lodders |date=10 July 2003 |title=Solar System Abundances and Condensation Temperatures of the Elements |journal=The Astrophysical Journal |publisher=The American Astronomical Society |volume=591 |issue=2 |pages=1220–1247 |url=http://weft.astro.washington.edu/courses/astro557/LODDERS.pdf |bibcode=2003ApJ...591.1220L |s2cid=42498829 |archive-url=https://web.archive.org/web/20151107043527/http://weft.astro.washington.edu/courses/astro557/LODDERS.pdf |archive-date=7 November 2015 |access-date=1 September 2015}} Graphed at [[:File:SolarSystemAbundances.jpg]]</ref> For related reasons, lithium has important uses in [[nuclear physics]]. The [[Nuclear transmutation|transmutation]] of lithium atoms to [[helium]] in 1932 was the first fully human-made [[nuclear reaction]], and [[lithium deuteride]] serves as a [[nuclear fusion|fusion]] fuel in [[Teller-Ulam design|staged thermonuclear weapons]].<ref>[https://web.archive.org/web/20160604211457/https://fas.org/nuke/intro/nuke/design.htm Nuclear Weapon Design]. Federation of American Scientists (21 October 1998). fas.org</ref>

Lithium and its compounds have several industrial applications, including heat-resistant glass and [[ceramic]]s, [[lithium grease]] lubricants, flux additives for iron, steel and aluminium production, [[Lithium metal battery|lithium metal batteries]], and [[lithium-ion battery|lithium-ion batteries]]. These uses consume more than three-quarters of lithium production.{{citation needed|date=March 2023}}{{when|date=March 2023}}

Lithium is present in biological systems in trace amounts. It has no established metabolic function in humans. [[Lithium (medication)|Lithium-based drugs]] are useful as a mood stabilizer and [[antidepressant]] in the treatment of mental illness such as [[bipolar disorder]].
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