Editing Lutetium (section)

===Chemical properties and compounds===
{{category see also|Lutetium compounds}}
Lutetium's compounds almost always contain the element in the +3 oxidation state.<ref>{{cite web|url=https://www.britannica.com/science/lutetium|title=Lutetium}}</ref> Aqueous solutions of most lutetium salts are colorless and form white crystalline solids upon drying, with the common exception of the iodide, which is brown. The soluble salts, such as nitrate, sulfate and acetate form hydrates upon crystallization. The [[lutetium(III) oxide|oxide]], hydroxide, fluoride, carbonate, phosphate and [[oxalate]] are insoluble in water.<ref name="patnaik" />

Lutetium metal is slightly unstable in air at standard conditions, but it burns readily at 150&nbsp;°C to form lutetium oxide. The resulting compound is known to absorb water and [[carbon dioxide]], and it may be used to remove vapors of these compounds from closed atmospheres.<ref name="aaaaaa">{{cite book| pages = [https://archive.org/details/historyuseourear00kreb_356/page/n327 303]–304| title = The history and use of our earth's chemical elements: a reference guide | url = https://archive.org/details/historyuseourear00kreb_356| url-access = limited| last= Krebs| first= Robert E.| publisher =Greenwood Publishing Group| date = 2006| isbn =978-0-313-33438-2}}</ref> Similar observations are made during reaction between lutetium and water (slow when cold and fast when hot); lutetium hydroxide is formed in the reaction.<ref name="ffff">{{cite web| url =https://www.webelements.com/lutetium/chemistry.html| title =Chemical reactions of Lutetium| publisher=Webelements| access-date=2009-06-06}}</ref> Lutetium metal is known to react with the four lightest halogens to form [[halides|trihalides]]; except the fluoride they are soluble in water. {{Citation needed|date=December 2024}}

Lutetium dissolves readily in weak acids<ref name="aaaaaa" /> and dilute [[sulfuric acid]] to form solutions containing the colorless lutetium ions, which are coordinated by between seven and nine water molecules, the average being {{chem2|[Lu(H2O)8.2](3+)}}.<ref name="Persson2010">{{cite journal|last1=Persson|first1=Ingmar|title=Hydrated metal ions in aqueous solution: How regular are their structures?|journal=Pure and Applied Chemistry|volume=82|issue=10|date=2010|pages=1901–1917|issn=0033-4545|doi=10.1351/PAC-CON-09-10-22|doi-access=free}}</ref>

:{{chem2|2 Lu + 3 H2SO4 → 2 Lu(3+) + 3 SO4(2-) + 3 H2↑}}