Editing Oxygen (section)

===Oxides and other inorganic compounds===
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[[Water]] ({{chem|H|2|O}}) is an oxide of [[hydrogen]] and the most familiar oxygen compound. Hydrogen atoms are [[covalent bonding|covalently bonded]] to oxygen in a water molecule but also have an additional attraction (about 23.3&nbsp;kJ/mol per hydrogen atom) to an adjacent oxygen atom in a separate molecule.<ref>{{cite journal|first1=P.|last1=Maksyutenko|first2=T. R.|last2=Rizzo|first3=O. V.|last3=Boyarkin|date=2006|title=A direct measurement of the dissociation energy of water|pmid=17115729|journal=J. Chem. Phys.|page=181101 |doi=10.1063/1.2387163|issue=18|volume=125|bibcode = 2006JChPh.125r1101M }}</ref> These [[hydrogen bond]]s between water molecules hold them approximately 15% closer than what would be expected in a simple liquid with just [[van der Waals force]]s.<ref>{{cite web|title=Water Hydrogen Bonding|last=Chaplin|first=Martin|url=http://www.lsbu.ac.uk/water/hbond.html|access-date=January 6, 2008|date=January 4, 2008|archive-date=October 10, 2007|archive-url=https://web.archive.org/web/20071010055658/http://www.lsbu.ac.uk/water/hbond.html|url-status=live}}</ref><ref group=lower-alpha>Also, since oxygen has a higher electronegativity than hydrogen, the charge difference makes it a [[polar molecule]]. The interactions between the different [[dipole]]s of each molecule cause a net attraction force.</ref>

[[File:Rust screw.jpg|thumb|left|Oxides, such as [[iron oxide]] or [[rust]], form when oxygen combines with other elements.|alt=A rusty piece of a bolt.]]
Due to its [[electronegativity]], oxygen forms [[chemical bond]]s with almost all other elements to give corresponding [[oxide]]s. The surface of most metals, such as [[aluminium]] and [[titanium]], are oxidized in the presence of air and become coated with a thin film of oxide that [[Passivation (chemistry)|passivates]] the metal and slows further [[corrosion]]. Many oxides of the [[transition metal]]s are [[non-stoichiometric compound]]s, with slightly less metal than the [[chemical formula]] would show. For example, the mineral [[Iron(II) oxide|FeO]] ([[wüstite]]) is written as <math chem>\ce{Fe}_{1-x}\ce{O}</math>, where ''x'' is usually around 0.05.<ref>{{cite book|first1=Lesley E.|last1=Smart|last2=Moore|first2=Elaine A. |title=Solid State Chemistry: An Introduction|edition=3rd |publisher=CRC Press|date=2005|page=214|isbn=978-0-7487-7516-3}}</ref>

Oxygen is present in the atmosphere in trace quantities in the form of [[carbon dioxide]] ({{chem|CO|2}}). The [[Earth's crust]]al [[Rock (geology)|rock]] is composed in large part of oxides of [[silicon]] ([[Silicon dioxide|silica]] {{chem|SiO|2}}, as found in [[granite]] and [[quartz]]), aluminium ([[aluminium oxide]] {{chem|Al|2|O|3}}, in [[bauxite]] and [[corundum]]), iron ([[iron(III) oxide]] {{chem|Fe|2|O|3}}, in [[hematite]] and [[rust]]), and [[calcium carbonate]] (in [[limestone]]). The rest of the Earth's crust is also made of oxygen compounds, in particular various complex [[silicate]]s (in [[silicate minerals]]). The Earth's mantle, of much larger mass than the crust, is largely composed of silicates of magnesium and iron.{{cn|date=May 2025}}

Water-[[solubility|soluble]] silicates in the form of {{chem|Na|4|SiO|4}}, {{chem|Na|2|SiO|3}}, and {{chem|Na|2|Si|2|O|5}} are used as [[detergent]]s and [[adhesive]]s.<ref name="ECE507">[[#Reference-idCook1968|Cook & Lauer 1968]], p. 507</ref>

Oxygen also acts as a [[ligand]] for transition metals, forming [[transition metal dioxygen complexes]], which feature metal–{{chem|O|2}}. This class of compounds includes the [[heme]] proteins [[hemoglobin]] and [[myoglobin]].<ref>{{cite book|last=Crabtree|first=R.|title=The Organometallic Chemistry of the Transition Metals|edition=3rd |publisher=John Wiley & Sons|date=2001|page=152|isbn=978-0-471-18423-2}}</ref> An exotic and unusual reaction occurs with [[platinum hexafluoride|{{chem|PtF|6}}]], which oxidizes oxygen to give O<sub>2</sub><sup>+</sup>PtF<sub>6</sub><sup>−</sup>, [[dioxygenyl hexafluoroplatinate]].<ref name="ECE505">[[#Reference-idCook1968|Cook & Lauer 1968]], p.505</ref>