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<title>Selenium dioxide</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Selenium dioxide</span></span>

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<caption>Selenium dioxide

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<th colspan="2" style="background: #f8eaba;color:inherit; text-align: center;">Names

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<td colspan="2" style="text-align:left;">Other names

<div style="max-width:22em; word-wrap:break-word; padding-left:1.7em;">Selenium(IV) oxide<br>Selenous anhydride</div>

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<th colspan="2" style="background: #f8eaba;color:inherit; text-align: center;">Identifiers

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="CAS_Registry_Number" title="CAS Registry Number">CAS Number</a></div>

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</style><div class="plainlist"><ul><li><span title="commonchemistry.cas.org"><a rel="nofollow" class="external text" href="https://commonchemistry.cas.org/detail?cas_rn=7446-08-4">7446-08-4</a></span><sup> <span typeof="mw:File"><span></span></span><span style="display:none">Y</span></sup></li></ul></div>

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">3D model (<a href="JSmol" class="mw-redirect" title="JSmol">JSmol</a>)</div>

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<td><div class="plainlist"><ul><li>monomer: <span title="chemapps.stolaf.edu (3D interactive model)"><a rel="nofollow" class="external text" href="https://chemapps.stolaf.edu/jmol/jmol.php?model=O%3D%5BSe%5D%3DO">Interactive image</a></span></li><li>polymer: <span title="chemapps.stolaf.edu (3D interactive model)"><a rel="nofollow" class="external text" href="https://chemapps.stolaf.edu/jmol/jmol.php?model=O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O%5BSe%5D%28%3DO%29O">Interactive image</a></span></li></ul></div>

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<td><a href="ChEMBL" title="ChEMBL">ChEMBL</a>

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<td><div class="plainlist"><ul><li><span title="www.ebi.ac.uk"><a rel="nofollow" class="external text" href="https://www.ebi.ac.uk/chembl/explore/compound/ChEMBL3183452">ChEMBL3183452</a></span></li></ul></div>

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<td><a href="ChemSpider" title="ChemSpider">ChemSpider</a>

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<td><a href="ECHA_InfoCard" class="mw-redirect" title="ECHA InfoCard"><span title="echa.europa.eu">ECHA InfoCard</span></a>

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<td><a href="European_Community_number" title="European Community number"><span title="European Community number (chemical identifier)">EC Number</span></a>

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="PubChem" title="PubChem">PubChem</a> <abbr title="Compound ID">CID</abbr></div>

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<td><a href="RTECS" class="mw-redirect" title="RTECS">RTECS number</a>

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<td><a href="UN_number" title="UN number">UN number</a>

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<td>3283

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="CompTox_Chemicals_Dashboard" title="CompTox Chemicals Dashboard">CompTox Dashboard</a> <span style="font-weight:normal">(<abbr title="U.S. Environmental Protection Agency">EPA</abbr>)</span></div>

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<td><div class="plainlist"><ul><li><span title="comptox.epa.gov"><a rel="nofollow" class="external text" href="https://comptox.epa.gov/dashboard/chemical/details/DTXSID4021264">DTXSID4021264</a> </span></li></ul></div>

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<div style="line-height: 1.6em; font-weight: bold; text-align:left; font-weight:normal;"><div><a href="International_Chemical_Identifier" title="International Chemical Identifier">InChI</a></div></div>

<ul class="mw-collapsible-content" style="margin-top: 0; margin-bottom: 0; line-height: inherit; list-style: none; margin-left: 0; word-break:break-all;"><li style="line-height: inherit; margin: 0"><div style="border-top:1px solid #ccc; padding:0.2em 0 0.2em 1.5em; text-align:left;"><div style="word-wrap:break-word; text-indent:-1.5em; font-size:97%; line-height:120%;">InChI=1S/O2Se/c1-3-2<sup> <span typeof="mw:File"><span></span></span><span style="display:none">Y</span></sup></div><div style="word-wrap:break-word; text-indent:-1.5em; font-size:97%; line-height:120%;">Key: JPJALAQPGMAKDF-UHFFFAOYSA-N<sup> <span typeof="mw:File"><span></span></span><span style="display:none">Y</span></sup></div></div></li><li style="line-height: inherit; margin: 0"><div style="border-top:1px solid #ccc; padding:0.2em 0 0.2em 1.5em; text-align:left;"><div style="word-wrap:break-word; text-indent:-1.5em; font-size:97%; line-height:120%;">InChI=1/O2Se/c1-3-2</div><div style="word-wrap:break-word; text-indent:-1.5em; font-size:97%; line-height:120%;">Key: JPJALAQPGMAKDF-UHFFFAOYAQ</div></div></li></ul>

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<div style="line-height: 1.6em; font-weight: bold; text-align:left; font-weight:normal;"><div><a href="Simplified_molecular-input_line-entry_system" class="mw-redirect" title="Simplified molecular-input line-entry system">SMILES</a></div></div>

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<th colspan="2" style="background: #f8eaba;color:inherit; text-align: center;">Properties

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Chemical_formula" title="Chemical formula">Chemical formula</a></div>

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<td><a href="Molar_mass" title="Molar mass">Molar mass</a>

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<td>110.96 g/mol

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<td>Appearance

</td>

<td>White crystals, turn slightly pink with trace decomposition<sup id="cite_ref-msds_1-0" class="reference"><a href="#cite_note-msds-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>

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</td>

<td>rotten radishes

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<td><a href="Density" title="Density">Density</a>

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<td>3.954 g/cm<sup>3</sup>, solid

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<td><a href="Melting_point" title="Melting point">Melting point</a>

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<td>340 °C (644 °F; 613 K) (sealed tube)

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<td><a href="Boiling_point" title="Boiling point">Boiling point</a>

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<td>350 °C (662 °F; 623 K) subl.

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Aqueous_solution" title="Aqueous solution">Solubility in water</a></div>

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<td>38.4 g/100 mL (20 °C) <br> 39.5 g/100 ml (25 °C) <br> 82.5 g/100 mL (65 °C)

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<td><a href="Solubility" title="Solubility">Solubility</a>

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<td>soluble in <a href="Benzene" title="Benzene">benzene</a>

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<td><a href="Solubility" title="Solubility">Solubility</a> in <a href="Ethanol" title="Ethanol">ethanol</a>

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<td>6.7 g/100 mL (15 °C)

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<td><a href="Solubility" title="Solubility">Solubility</a> in <a href="Acetone" title="Acetone">acetone</a>

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<td>4.4 g/100 mL (15 °C)

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<td><a href="Solubility" title="Solubility">Solubility</a> in <a href="Acetic_acid" title="Acetic acid">acetic acid</a>

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<td>1.11 g/100 mL (14 °C)

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<td><a href="Solubility" title="Solubility">Solubility</a> in <a href="Methanol" title="Methanol">methanol</a>

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<td>10.16 g/100 mL (12 °C)

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<td><a href="Vapor_pressure" title="Vapor pressure">Vapor pressure</a>

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<td>1.65 kPa (70 °C)

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<td><a href="Acid_dissociation_constant" title="Acid dissociation constant">Acidity</a> (p<i>K</i><sub>a</sub>)

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<td>2.62; 8.32

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Magnetic_susceptibility" title="Magnetic susceptibility">Magnetic susceptibility</a> (χ)</div>

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<td>−27.2·10<sup>−6</sup> cm<sup>3</sup>/mol

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Refractive_index" title="Refractive index">Refractive index</a> (<i>n</i><sub>D</sub>)</div>

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<td>> 1.76

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<th colspan="2" style="background: #f8eaba;color:inherit; text-align: center;">Structure

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Crystal_structure" title="Crystal structure">Crystal structure</a></div>

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Coordination_geometry" title="Coordination geometry">Coordination geometry</a></div>

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<td>trigonal (Se)

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<th colspan="2" style="background: #f8eaba;color:inherit; text-align: center;">Hazards

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<td colspan="2" style="text-align:left; background-color:#eaeaea;color:inherit;"><b><a href="Occupational_safety_and_health" title="Occupational safety and health">Occupational safety and health</a></b> (OHS/OSH):

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<td style="padding-left:1em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Main hazards</div>

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<td>Toxic by ingestion and inhalation<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>

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<td colspan="2" style="text-align:left; background-color:#eaeaea;color:inherit;"><a href="Globally_Harmonized_System_of_Classification_and_Labelling_of_Chemicals" title="Globally Harmonized System of Classification and Labelling of Chemicals"><b>GHS</b> labelling</a>:

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<td style="padding-left:1em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="GHS_hazard_pictograms" title="GHS hazard pictograms">Pictograms</a></div>

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<td style="padding-left:1em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="Globally_Harmonized_System_of_Classification_and_Labelling_of_Chemicals#Signal_word" title="Globally Harmonized System of Classification and Labelling of Chemicals">Signal word</a></div>

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<td><b>Danger</b>

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<td style="padding-left:1em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="GHS_hazard_statements" title="GHS hazard statements">Hazard statements</a></div>

</td>

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<td style="padding-left:1em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="GHS_precautionary_statements" title="GHS precautionary statements">Precautionary statements</a></div>

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<td><a href="NFPA_704" title="NFPA 704"><b>NFPA 704</b></a> (fire diamond)

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<td><a href="Flash_point" title="Flash point">Flash point</a>

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<td>Non-flammable

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<td colspan="2" style="text-align:left; background-color:#eaeaea;color:inherit;"><b>Lethal dose</b> or concentration (LD, LC):

</td></tr>

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<td style="padding-left:1em;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">LC<sub>Lo</sub> (<a href="Lethal_dose#LCLo" title="Lethal dose">lowest published</a>)</div>

</td>

<td>5890 mg/m<sup>3</sup> (rabbit, 20 min)<br>6590 mg/m<sup>3</sup> (goat, 10 min)<br>6590 mg/m<sup>3</sup> (sheep, 10 min)<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

</td></tr>

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<td><a href="Safety_data_sheet" title="Safety data sheet">Safety data sheet</a> (SDS)

</td>

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<th colspan="2" style="background: #f8eaba;color:inherit; text-align: center;">Related compounds

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Other <a href="Ion" title="Ion">anions</a></div>

</td>

<td><a href="Selenium_disulfide" title="Selenium disulfide">Selenium disulfide</a>

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Other <a href="Ion" title="Ion">cations</a></div>

</td>

<td><a href="Ozone" title="Ozone">Ozone</a><br><a href="Sulfur_dioxide" title="Sulfur dioxide">Sulfur dioxide</a><br><a href="Tellurium_dioxide" title="Tellurium dioxide">Tellurium dioxide</a>

</td></tr>

<tr>

<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Related <a href="Selenium" title="Selenium">selenium</a> <a href="Oxide" title="Oxide">oxides</a></div>

</td>

<td><a href="Selenium_trioxide" title="Selenium trioxide">Selenium trioxide</a>

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<td><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Related compounds</div>

</td>

<td><a href="Selenous_acid" title="Selenous acid">Selenous acid</a>

</td></tr>

<tr>

<td colspan="2" style="text-align:left; background:#f8eaba; color:inherit; border:1px solid #a2a9b1;"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Except where otherwise noted, data are given for materials in their <a href="Standard_state" title="Standard state">standard state</a> (at 25 °C [77 °F], 100 kPa).</div>

<div style="margin-top: 0.3em;"><div style="text-align:center;"><span typeof="mw:File"><span></span></span><span style="display:none">Y</span> <span class="reflink nourlexpansion"><a class="external text external" href="https://en.wikipedia.org/w/index.php?title=Special:ComparePages&rev1=464388515&page2=Selenium+dioxide">verify</a></span> (what is <sup><span typeof="mw:File"><span></span></span><span style="display:none">Y</span><span typeof="mw:File"><span></span></span><span style="display:none">N</span></sup> ?)

</div></div>

<div style="margin-top: 0.3em; text-align: center;">Infobox references</div>

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<p><b>Selenium dioxide</b> is the <a href="Chemical_compound" title="Chemical compound">chemical compound</a> with the <a href="Chemical_formula" title="Chemical formula">formula</a> SeO<sub>2</sub>. This colorless solid is one of the most frequently encountered compounds of <a href="Selenium" title="Selenium">selenium</a>. It is used in making specialized glasses as well as a reagent in organic chemistry.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="Properties">Properties</h2></div>

<p>Solid SeO<sub>2</sub> is a one-dimensional <a href="Polymer" title="Polymer">polymer</a>, the chain consisting of alternating selenium and <a href="Oxygen" title="Oxygen">oxygen</a> atoms. Each Se atom is pyramidal and bears a terminal oxide group. The bridging Se-O bond lengths are 179 pm and the terminal Se-O distance is 162 pm.<sup id="cite_ref-Devillanova_5-0" class="reference"><a href="#cite_note-Devillanova-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> The relative <a href="Stereochemistry" title="Stereochemistry">stereochemistry</a> at Se alternates along the polymer chain (<a href="Syndiotactic" class="mw-redirect" title="Syndiotactic">syndiotactic</a>).

In the gas phase selenium dioxide is present as dimers and other oligomeric species, at higher temperatures it is monomeric.<sup id="cite_ref-Holl&Wib_6-0" class="reference"><a href="#cite_note-Holl&Wib-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> The monomeric form adopts a bent structure very similar to that of <a href="Sulfur_dioxide" title="Sulfur dioxide">sulfur dioxide</a> with a bond length of 161 pm.<sup id="cite_ref-Holl&Wib_6-1" class="reference"><a href="#cite_note-Holl&Wib-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> The dimeric form has been isolated in a low temperature argon matrix and vibrational spectra indicate that it has a centrosymmetric chair form.<sup id="cite_ref-Devillanova_5-1" class="reference"><a href="#cite_note-Devillanova-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> Dissolution of SeO<sub>2</sub> in <a href="Selenium_oxydichloride" title="Selenium oxydichloride">selenium oxydichloride</a> give the trimer [Se(O)O]<sub>3</sub>.<sup id="cite_ref-Holl&Wib_6-2" class="reference"><a href="#cite_note-Holl&Wib-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>

Monomeric SeO<sub>2</sub> is a polar molecule, with the dipole moment of 2.62 D <sup id="cite_ref-TakeoHirota1972_7-0" class="reference"><a href="#cite_note-TakeoHirota1972-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> pointed from the midpoint of the two oxygen atoms to the selenium atom.

</p><p>The solid sublimes readily. At very low concentrations the vapour has a revolting odour, resembling decayed horseradishes. At higher concentrations the vapour has an odour resembling horseradish sauce and can burn the nose and throat on inhalation. Whereas SO<sub>2</sub> tends to be molecular and SeO<sub>2</sub> is a one-dimensional chain, <a href="Tellurium_dioxide" title="Tellurium dioxide">TeO<sub>2</sub></a> is a cross-linked polymer.<sup id="cite_ref-Devillanova_5-2" class="reference"><a href="#cite_note-Devillanova-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup>

</p><p>SeO<sub>2</sub> is considered an <a href="Acidic_oxide" title="Acidic oxide">acidic oxide</a>: it dissolves in water to form <a href="Selenous_acid" title="Selenous acid">selenous acid</a>.<sup id="cite_ref-Holl&Wib_6-3" class="reference"><a href="#cite_note-Holl&Wib-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Often the terms <i><a href="Selenous_acid" title="Selenous acid">selenous acid</a></i> and <i>selenium dioxide</i> are used interchangeably. It reacts with base to form <a href="Selenite_(ion)" title="Selenite (ion)">selenite</a> <a href="Salt_(chemistry)" title="Salt (chemistry)">salts</a> containing the <span class="chemf nowrap">SeO<span class="nowrap"><span style="display:inline-block;margin-bottom:-0.3em;vertical-align:-0.4em;line-height:1em;font-size:80%;text-align:left"><sup style="font-size:inherit;line-height:inherit;vertical-align:baseline">2−</sup><br><sub style="font-size:inherit;line-height:inherit;vertical-align:baseline">3</sub></span></span></span> anion. For example, reaction with <a href="Sodium_hydroxide" title="Sodium hydroxide">sodium hydroxide</a> produces <a href="Sodium_selenite" title="Sodium selenite">sodium selenite</a>:

</p>

<div class="mw-heading mw-heading2"><h2 id="Preparation">Preparation</h2></div>

<p>Selenium dioxide is prepared by oxidation of <a href="Selenium" title="Selenium">selenium</a> by burning in air or by reaction with nitric acid or <a href="Hydrogen_peroxide" title="Hydrogen peroxide">hydrogen peroxide</a>, but perhaps the most convenient preparation is by the dehydration of <a href="Selenous_acid" title="Selenous acid">selenous acid</a>.

</p>

<div class="mw-heading mw-heading2"><h2 id="Occurrence">Occurrence</h2></div>

<p>The natural form of selenium dioxide, downeyite, is a very rare mineral. It is only found at a small number of <a href="Coal-seam_fire" title="Coal-seam fire">burning coal banks</a>, where it forms around vents created from escaping gasses.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading3"><h3 id="Organic_synthesis">Organic synthesis</h3></div>

<p>SeO<sub>2</sub> is an important reagent in <a href="Organic_synthesis" title="Organic synthesis">organic synthesis</a>. Oxidation of <a href="Paraldehyde" title="Paraldehyde">paraldehyde</a> (acetaldehyde trimer) with SeO<sub>2</sub> gives <a href="Glyoxal" title="Glyoxal">glyoxal</a><sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> and the oxidation of <a href="Cyclohexanone" title="Cyclohexanone">cyclohexanone</a> gives <a href="1%2C2-Cyclohexanedione" title="1,2-Cyclohexanedione">1,2-cyclohexanedione</a>.<sup id="cite_ref-Hachorgsyn_10-0" class="reference"><a href="#cite_note-Hachorgsyn-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> The selenium starting material is <a href="Redox" title="Redox">reduced</a> to selenium, and precipitates as a red <a href="Amorphous_solid" title="Amorphous solid">amorphous solid</a> which can easily be filtered off.<sup id="cite_ref-Hachorgsyn_10-1" class="reference"><a href="#cite_note-Hachorgsyn-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> This type of reaction is called a <a href="Riley_oxidation" title="Riley oxidation">Riley oxidation</a>. It is also renowned as a reagent for <a href="Allylic_oxidation" class="mw-redirect" title="Allylic oxidation">allylic oxidation</a>,<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> a reaction that entails the following conversion

</p>

<p>This can be described more generally as;

</p>

<p>where R, R', R" may be <a href="Alkyl" class="mw-redirect" title="Alkyl">alkyl</a> or <a href="Aryl" class="mw-redirect" title="Aryl">aryl</a> substituents.

</p><p>Selenium dioxide can also be used to synthesize 1,2,3-selenadiazoles from acylated hydrazone derivatives.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading3"><h3 id="As_a_colorant">As a colorant</h3></div>

<p>Selenium dioxide imparts a red colour to <a href="Glass" title="Glass">glass</a>. It is used in small quantities to counteract the colour due to <a href="Iron" title="Iron">iron</a> impurities and so to create (apparently) colourless glass. In larger quantities, it gives a deep ruby red colour.

</p><p>Selenium dioxide is the active ingredient in some <a href="Bluing_(steel)" title="Bluing (steel)">cold-bluing</a> solutions.

</p><p>It was also used as a toner in <a href="Photographic_developing" class="mw-redirect" title="Photographic developing">photographic developing</a>.

</p>

<div class="mw-heading mw-heading3"><h3 id="Safety">Safety</h3></div>

<p>Selenium is an <a href="Essential_element" class="mw-redirect" title="Essential element">essential element</a>, but ingestion of more than 5 mg/day leads to <a href="Nonspecific_symptom" class="mw-redirect" title="Nonspecific symptom">nonspecific symptoms</a>.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup>

</p>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.integrachem.com/msds/S138_26294_101.pdf">"Safety data sheet: Selenium dioxide"</a> <span class="cs1-format">(PDF)</span>. <i>integrachem.com</i>. 27 March 2015<span class="reference-accessdate">. Retrieved <span class="nowrap">2022-12-02</span></span>.</cite></span>

</li>

<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://pubchem.ncbi.nlm.nih.gov/compound/Selenium-dioxide#section=Safety-and-Hazards">"Selenium dioxide safety and hazards"</a>. <i>pubchem.ncbi.nlm.nih.gov</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2022-12-02</span></span>.</cite></span>

</li>

<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.cdc.gov/niosh/idlh/7782492.html">"Selenium compounds (as Se)"</a>. <i>Immediately Dangerous to Life or Health Concentrations (IDLH)</i>. <a href="National_Institute_for_Occupational_Safety_and_Health" title="National Institute for Occupational Safety and Health">National Institute for Occupational Safety and Health</a> (NIOSH).</cite></span>

</li>

<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><cite id="CITEREFHoekstraFairlambGirouxChen2017" class="citation book cs1">Hoekstra, William J.; Fairlamb, Ian J. S.; Giroux, Simon; Chen, Yuzhong (2017). "Selenium(IV) Oxide". <i>Encyclopedia of Reagents for Organic Synthesis</i>. pp. <span class="nowrap">1–</span>12. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1002%2F047084289X.rs008.pub3">10.1002/047084289X.rs008.pub3</a>. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-470-84289-8</bdi>.</cite></span>

</li>

<li id="cite_note-Devillanova-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-Devillanova_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Devillanova_5-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Devillanova_5-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text">Handbook of Chalcogen Chemistry: New Perspectives in Sulfur, Selenium and Tellurium, Franceso A. Devillanova, Royal Society of Chemistry, 2007, <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>9780854043668</bdi></span>

</li>

<li id="cite_note-Holl&Wib-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-Holl&Wib_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Holl&Wib_6-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Holl&Wib_6-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Holl&Wib_6-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFHollemanWiberg2001" class="citation cs2">Holleman, Arnold Frederik; Wiberg, Egon (2001), Wiberg, Nils (ed.), <i>Inorganic Chemistry</i>, translated by Eagleson, Mary; Brewer, William, San Diego/Berlin: Academic Press/De Gruyter, <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-12-352651-5</bdi></cite></span>

</li>

<li id="cite_note-TakeoHirota1972-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-TakeoHirota1972_7-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFTakeoHirotaMorino1972" class="citation journal cs1">Takeo, Harutoshi; Hirota, Eizi; Morino, Yonezo (1972). "Third-order potential constants and dipole moment of SeO2 by microwave spectroscopy". <i>Journal of Molecular Spectroscopy</i>. <b>41</b> (2): <span class="nowrap">420–</span>422. <a href="Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1972JMoSp..41..420T">1972JMoSp..41..420T</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2F0022-2852%2872%2990216-0">10.1016/0022-2852(72)90216-0</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0022-2852">0022-2852</a>.</cite></span>

</li>

<li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><cite id="CITEREFFinkelmanMrose1977" class="citation journal cs1">Finkelman, Robert B.; Mrose, Mary E. (1977). <a rel="nofollow" class="external text" href="http://www.minsocam.org/ammin/AM62/AM62_316.pdf">"Downeyite, the first verified natural occurrence of SeO<sub>2</sub>"</a> <span class="cs1-format">(PDF)</span>. <i><a href="American_Mineralogist" title="American Mineralogist">American Mineralogist</a></i>. <b>62</b>: <span class="nowrap">316–</span>320.</cite></span>

</li>

<li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><cite id="CITEREFRonzio,_A._R.;_Waugh,_T._D.1955" class="citation journal cs1">Ronzio, A. R.; Waugh, T. D. (1955). <a rel="nofollow" class="external text" href="http://www.orgsyn.org/demo.aspx?prep=CV3P0438">"Glyoxal Bisulfite"</a>. <i><a href="Organic_Syntheses" title="Organic Syntheses">Organic Syntheses</a></i></cite><span class="cs1-maint citation-comment"><code class="cs1-code">{{cite journal}}</code>: CS1 maint: multiple names: authors list (link)</span>; <cite class="citation cs2"><i>Collected Volumes</i>, vol. 3, p. 438</cite>.</span>

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<li id="cite_note-Hachorgsyn-10"><span class="mw-cite-backlink">^ <a href="#cite_ref-Hachorgsyn_10-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Hachorgsyn_10-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><cite id="CITEREFHach,_C._C._Banks,_C._V.;_Diehl,_H.1963" class="citation journal cs1">Hach, C. C. Banks, C. V.; Diehl, H. (1963). <a rel="nofollow" class="external text" href="http://www.orgsyn.org/demo.aspx?prep=CV4P0229">"1,2-Cyclohexanedione Dioxime"</a>. <i><a href="Organic_Syntheses" title="Organic Syntheses">Organic Syntheses</a></i></cite><span class="cs1-maint citation-comment"><code class="cs1-code">{{cite journal}}</code>: CS1 maint: multiple names: authors list (link)</span>; <cite class="citation cs2"><i>Collected Volumes</i>, vol. 4, p. 229</cite>.</span>

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<li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><cite id="CITEREFCoxon,_J._M.;_Dansted,_E.;_Hartshorn,_M._P.1977" class="citation journal cs1">Coxon, J. M.; Dansted, E.; <a href="Michael_Hartshorn" title="Michael Hartshorn">Hartshorn, M. P.</a> (1977). "Allylic Oxidation with Hydrogen Peroxide–Selenium Dioxide: trans-Pinocarveol". <i><a href="Organic_Syntheses" title="Organic Syntheses">Organic Syntheses</a></i>. <b>56</b>: 25. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.15227%2Forgsyn.056.0025">10.15227/orgsyn.056.0025</a></cite><span class="cs1-maint citation-comment"><code class="cs1-code">{{cite journal}}</code>: CS1 maint: multiple names: authors list (link)</span>.</span>

</li>

<li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><cite id="CITEREFLalezariShafieeYalpani1969" class="citation journal cs1"><a href="Iraj_Lalezari" title="Iraj Lalezari">Lalezari, Iraj</a>; Shafiee, Abbas; Yalpani, Mohamed (1969). "A novel synthesis of selenium heterocycles: substituted 1,2,3-selenadiazoles". <i>Tetrahedron Letters</i>. <b>10</b> (58): <span class="nowrap">5105–</span>5106. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2FS0040-4039%2801%2988895-X">10.1016/S0040-4039(01)88895-X</a>.</cite></span>

</li>

<li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text">Bernd E. Langner "Selenium and Selenium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1002%2F14356007.a23_525">10.1002/14356007.a23_525</a></span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

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<div class="side-box-text plainlist">Wikimedia Commons has media related to <span style="font-weight: bold; font-style: italic;"><a href="https://commons.wikimedia.org/wiki/Category:Selenium_dioxide" class="extiw external" title="commons:Category:Selenium dioxide">selenium dioxide</a></span>.</div></div>

</div>

<ul><li><a rel="nofollow" class="external text" href="https://www.ilo.org/dyn/icsc/showcard.display?p_lang=en&p_card_id=0946&p_version=2">International Chemical Safety Card 0946</a></li></ul>

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</style><div id="Selenium_compounds70" style="font-size:114%;margin:0 4em"><a href="Selenium" title="Selenium">Selenium</a> compounds</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Se(−II)</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Se(0,I)</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Se(I)</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Se(II)</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Se(IV)</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Selenium_oxydichloride" title="Selenium oxydichloride">SeOCl<sub>2</sub></a></li>

<li><a href="Selenium_oxybromide" title="Selenium oxybromide">SeOBr<sub>2</sub></a></li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Se(VI)</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Se(IV,VI)</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

</div></td></tr></tbody></table></div>

<div class="navbox-styles"></div><div role="navigation" class="navbox" aria-labelledby="Oxides245" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Oxides245" style="font-size:114%;margin:0 4em"><a href="Oxide" title="Oxide">Oxides</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Mixed oxidation states</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Antimony_tetroxide" title="Antimony tetroxide">Antimony tetroxide</a> (<a href="Antimony" title="Antimony">Sb</a><sub>2</sub>O<sub>4</sub>)</li>

<li><a href="Boron_suboxide" title="Boron suboxide">Boron suboxide</a> (<a href="Boron" title="Boron">B</a><sub>12</sub>O<sub>2</sub>)</li>

<li><a href="Carbon_suboxide" title="Carbon suboxide">Carbon suboxide</a> (<a href="Carbon" title="Carbon">C</a><sub>3</sub>O<sub>2</sub>)</li>

<li><a href="Chlorine_perchlorate" title="Chlorine perchlorate">Chlorine perchlorate</a> (<a href="Chlorine" title="Chlorine">Cl</a><sub>2</sub>O<sub>4</sub>)</li>

<li><a href="Chloryl_perchlorate" class="mw-redirect" title="Chloryl perchlorate">Chloryl perchlorate</a> (<a href="Chlorine" title="Chlorine">Cl</a><sub>2</sub>O<sub>6</sub>)</li>

<li><a href="Cobalt(II%2CIII)_oxide" title="Cobalt(II,III) oxide">Cobalt(II,III) oxide</a> (<a href="Cobalt" title="Cobalt">Co</a><sub>3</sub>O<sub>4</sub>)</li>

<li><a href="Dichlorine_pentoxide" title="Dichlorine pentoxide">Dichlorine pentoxide</a> (<a href="Chlorine" title="Chlorine">Cl</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Iron(II%2CIII)_oxide" title="Iron(II,III) oxide">Iron(II,III) oxide</a> (<a href="Iron" title="Iron">Fe</a><sub>3</sub>O<sub>4</sub>)</li>

<li><a href="Lead(II%2CIV)_oxide" title="Lead(II,IV) oxide">Lead(II,IV) oxide</a> (<a href="Lead" title="Lead">Pb</a><sub>3</sub>O<sub>4</sub>)</li>

<li><a href="Manganese(II%2CIII)_oxide" title="Manganese(II,III) oxide">Manganese(II,III) oxide</a> (<a href="Manganese" title="Manganese">Mn</a><sub>3</sub>O<sub>4</sub>)</li>

<li><a href="Mellitic_anhydride" title="Mellitic anhydride">Mellitic anhydride</a> (<a href="Carbon" title="Carbon">C</a><sub>12</sub>O<sub>9</sub>)</li>

<li><a href="Praseodymium(III%2CIV)_oxide" title="Praseodymium(III,IV) oxide">Praseodymium(III,IV) oxide</a> (<a href="Praseodymium" title="Praseodymium">Pr</a><sub>6</sub>O<sub>11</sub>)</li>

<li><a href="Silver(I%2CIII)_oxide" title="Silver(I,III) oxide">Silver(I,III) oxide</a> (<a href="Silver" title="Silver">Ag</a><sub>2</sub>O<sub>2</sub>)</li>

<li><a href="Terbium(III%2CIV)_oxide" title="Terbium(III,IV) oxide">Terbium(III,IV) oxide</a> (<a href="Terbium" title="Terbium">Tb</a><sub>4</sub>O<sub>7</sub>)</li>

<li><a href="Tribromine_octoxide" title="Tribromine octoxide">Tribromine octoxide</a> (<a href="Bromine" title="Bromine">Br</a><sub>3</sub>O<sub>8</sub>)</li>

<li><a href="Triuranium_octoxide" title="Triuranium octoxide">Triuranium octoxide</a> (<a href="Uranium" title="Uranium">U</a><sub>3</sub>O<sub>8</sub>)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">+1 oxidation state</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Aluminium(I)_oxide" title="Aluminium(I) oxide">Aluminium(I) oxide</a> (<a href="Aluminium" title="Aluminium">Al</a><sub>2</sub>O)</li>

<li><a href="Copper(I)_oxide" title="Copper(I) oxide">Copper(I) oxide</a> (<a href="Copper" title="Copper">Cu</a><sub>2</sub>O)</li>

<li><a href="Caesium_monoxide" title="Caesium monoxide">Caesium monoxide</a> (<a href="Caesium" title="Caesium">Cs</a><sub>2</sub>O)</li>

<li><a href="Dibromine_monoxide" title="Dibromine monoxide">Dibromine monoxide</a> (<a href="Bromine" title="Bromine">Br</a><sub>2</sub>O)</li>

<li><a href="Dicarbon_monoxide" title="Dicarbon monoxide">Dicarbon monoxide</a> (<a href="Carbon" title="Carbon">C</a><sub>2</sub>O)</li>

<li><a href="Dichlorine_monoxide" title="Dichlorine monoxide">Dichlorine monoxide</a> (<a href="Chlorine" title="Chlorine">Cl</a><sub>2</sub>O)</li>

<li><a href="Gallium(I)_oxide" title="Gallium(I) oxide">Gallium(I) oxide</a> (<a href="Gallium" title="Gallium">Ga</a><sub>2</sub>O)</li>

<li><a href="Iodine(I)_oxide" class="mw-redirect" title="Iodine(I) oxide">Iodine(I) oxide</a> (<a href="Iodine" title="Iodine">I</a><sub>2</sub>O)</li>

<li><a href="Lithium_oxide" title="Lithium oxide">Lithium oxide</a> (<a href="Lithium" title="Lithium">Li</a><sub>2</sub>O)</li>

<li><a href="Mercury(I)_oxide" title="Mercury(I) oxide">Mercury(I) oxide</a> (<a href="Mercury_(element)" title="Mercury (element)">Hg</a><sub>2</sub>O)</li>

<li><a href="Nitrous_oxide" title="Nitrous oxide">Nitrous oxide</a> (<a href="Nitrogen" title="Nitrogen">N</a><sub>2</sub>O)</li>

<li><a href="Potassium_oxide" title="Potassium oxide">Potassium oxide</a> (<a href="Potassium" title="Potassium">K</a><sub>2</sub>O)</li>

<li><a href="Rubidium_oxide" title="Rubidium oxide">Rubidium oxide</a> (<a href="Rubidium" title="Rubidium">Rb</a><sub>2</sub>O)</li>

<li><a href="Silver_oxide" title="Silver oxide">Silver oxide</a> (<a href="Silver" title="Silver">Ag</a><sub>2</sub>O)</li>

<li><a href="Thallium(I)_oxide" title="Thallium(I) oxide">Thallium(I) oxide</a> (<a href="Thallium" title="Thallium">Tl</a><sub>2</sub>O)</li>

<li><a href="Sodium_oxide" title="Sodium oxide">Sodium oxide</a> (<a href="Sodium" title="Sodium">Na</a><sub>2</sub>O)</li>

<li><a href="Properties_of_water" title="Properties of water">Water (hydrogen oxide)</a> (<a href="Hydrogen" title="Hydrogen">H</a><sub>2</sub>O)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">+2 oxidation state</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Aluminium(II)_oxide" title="Aluminium(II) oxide">Aluminium(II) oxide</a> (<a href="Aluminium" title="Aluminium">Al</a>O)</li>

<li><a href="Barium_oxide" title="Barium oxide">Barium oxide</a> (<a href="Barium" title="Barium">Ba</a>O)</li>

<li><a href="Berkelium_monoxide" class="mw-redirect" title="Berkelium monoxide">Berkelium monoxide</a> (<a href="Berkelium" title="Berkelium">Bk</a>O)</li>

<li><a href="Beryllium_oxide" title="Beryllium oxide">Beryllium oxide</a> (<a href="Beryllium" title="Beryllium">Be</a>O)</li>

<li><a href="Boron_monoxide" title="Boron monoxide">Boron monoxide</a> (<a href="Boron" title="Boron">B</a>O)</li>

<li><a href="Bromine_monoxide" class="mw-redirect" title="Bromine monoxide">Bromine monoxide</a> (<a href="Bromine" title="Bromine">Br</a>O)</li>

<li><a href="Cadmium_oxide" title="Cadmium oxide">Cadmium oxide</a> (<a href="Cadmium" title="Cadmium">Cd</a>O)</li>

<li><a href="Calcium_oxide" title="Calcium oxide">Calcium oxide</a> (<a href="Calcium" title="Calcium">Ca</a>O)</li>

<li><a href="Carbon_monoxide" title="Carbon monoxide">Carbon monoxide</a> (<a href="Carbon" title="Carbon">C</a>O)</li>

<li><a href="Chlorine_monoxide" title="Chlorine monoxide">Chlorine monoxide</a> (<a href="Chlorine" title="Chlorine">Cl</a>O)</li>

<li><a href="Chromium(II)_oxide" title="Chromium(II) oxide">Chromium(II) oxide</a> (<a href="Chromium" title="Chromium">Cr</a>O)</li>

<li><a href="Cobalt(II)_oxide" title="Cobalt(II) oxide">Cobalt(II) oxide</a> (<a href="Cobalt" title="Cobalt">Co</a>O)</li>

<li><a href="Copper(II)_oxide" title="Copper(II) oxide">Copper(II) oxide</a> (<a href="Copper" title="Copper">Cu</a>O)</li>

<li><a href="Dinitrogen_dioxide" title="Dinitrogen dioxide">Dinitrogen dioxide</a> (<a href="Nitrogen" title="Nitrogen">N</a><sub>2</sub>O<sub>2</sub>)</li>

<li><a href="Disulfur_dioxide" title="Disulfur dioxide">Disulfur dioxide</a> (<a href="Sulfur" title="Sulfur">S</a><sub>2</sub>O<sub>2</sub>)</li>

<li><a href="Europium(II)_oxide" title="Europium(II) oxide">Europium(II) oxide</a> (<a href="Europium" title="Europium">Eu</a>O)</li>

<li><a href="Germanium_monoxide" title="Germanium monoxide">Germanium monoxide</a> (<a href="Germanium" title="Germanium">Ge</a>O)</li>

<li><a href="Iron(II)_oxide" title="Iron(II) oxide">Iron(II) oxide</a> (<a href="Iron" title="Iron">Fe</a>O)</li>

<li><a href="Iodine_monoxide" title="Iodine monoxide">Iodine monoxide</a> (<a href="Iodine" title="Iodine">I</a>O)</li>

<li><a href="Lead(II)_oxide" title="Lead(II) oxide">Lead(II) oxide</a> (<a href="Lead" title="Lead">Pb</a>O)</li>

<li><a href="Magnesium_oxide" title="Magnesium oxide">Magnesium oxide</a> (<a href="Magnesium" title="Magnesium">Mg</a>O)</li>

<li><a href="Manganese(II)_oxide" title="Manganese(II) oxide">Manganese(II) oxide</a> (<a href="Manganese" title="Manganese">Mn</a>O)</li>

<li><a href="Mercury(II)_oxide" title="Mercury(II) oxide">Mercury(II) oxide</a> (<a href="Mercury_(element)" title="Mercury (element)">Hg</a>O)</li>

<li><a href="Nickel(II)_oxide" title="Nickel(II) oxide">Nickel(II) oxide</a> (<a href="Nickel" title="Nickel">Ni</a>O)</li>

<li><a href="Nitric_oxide" title="Nitric oxide">Nitric oxide</a> (<a href="Nitrogen" title="Nitrogen">N</a>O)</li>

<li><a href="Niobium_monoxide" title="Niobium monoxide">Niobium monoxide</a> (<a href="Niobium" title="Niobium">Nb</a>O)</li>

<li><a href="Palladium(II)_oxide" title="Palladium(II) oxide">Palladium(II) oxide</a> (<a href="Palladium" title="Palladium">Pd</a>O)</li>

<li><a href="Phosphorus_monoxide" title="Phosphorus monoxide">Phosphorus monoxide</a> (<a href="Phosphorus" title="Phosphorus">P</a>O)</li>

<li><a href="Polonium_monoxide" title="Polonium monoxide">Polonium monoxide</a> (<a href="Polonium" title="Polonium">Po</a>O)</li>

<li><a href="Protactinium_monoxide" title="Protactinium monoxide">Protactinium monoxide</a> (<a href="Protactinium" title="Protactinium">Pa</a>O)</li>

<li><a href="Radium_oxide" title="Radium oxide">Radium oxide</a> (<a href="Radium" title="Radium">Ra</a>O)</li>

<li><a href="Silicon_monoxide" title="Silicon monoxide">Silicon monoxide</a> (<a href="Silicon" title="Silicon">Si</a>O)</li>

<li><a href="Strontium_oxide" title="Strontium oxide">Strontium oxide</a> (<a href="Strontium" title="Strontium">Sr</a>O)</li>

<li><a href="Sulfur_monoxide" title="Sulfur monoxide">Sulfur monoxide</a> (<a href="Sulfur" title="Sulfur">S</a>O)</li>

<li><a href="Thorium_monoxide" title="Thorium monoxide">Thorium monoxide</a> (<a href="Thorium" title="Thorium">Th</a>O)</li>

<li><a href="Tin(II)_oxide" title="Tin(II) oxide">Tin(II) oxide</a> (<a href="Tin" title="Tin">Sn</a>O)</li>

<li><a href="Titanium(II)_oxide" title="Titanium(II) oxide">Titanium(II) oxide</a> (<a href="Titanium" title="Titanium">Ti</a>O)</li>

<li><a href="Vanadium(II)_oxide" title="Vanadium(II) oxide">Vanadium(II) oxide</a> (<a href="Vanadium" title="Vanadium">V</a>O)</li>

<li><a href="Yttrium(II)_oxide" title="Yttrium(II) oxide">Yttrium(II) oxide</a> (<a href="Yttrium" title="Yttrium">Y</a>O)</li>

<li><a href="Zirconium_monoxide" class="mw-redirect" title="Zirconium monoxide">Zirconium monoxide</a> (<a href="Zirconium" title="Zirconium">Zr</a>O)</li>

<li><a href="Zinc_oxide" title="Zinc oxide">Zinc oxide</a> (<a href="Zinc" title="Zinc">Zn</a>O)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">+3 oxidation state</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Actinium(III)_oxide" title="Actinium(III) oxide">Actinium(III) oxide</a> (<a href="Actinium" title="Actinium">Ac</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Aluminium_oxide" title="Aluminium oxide">Aluminium oxide</a> (<a href="Aluminium" title="Aluminium">Al</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Americium(III)_oxide" title="Americium(III) oxide">Americium(III) oxide</a> (<a href="Americium" title="Americium">Am</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Antimony_trioxide" title="Antimony trioxide">Antimony trioxide</a> (<a href="Antimony" title="Antimony">Sb</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Arsenic_trioxide" title="Arsenic trioxide">Arsenic trioxide</a> (<a href="Arsenic" title="Arsenic">As</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Berkelium(III)_oxide" title="Berkelium(III) oxide">Berkelium(III) oxide</a> (<a href="Berkelium" title="Berkelium">Bk</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Bismuth(III)_oxide" title="Bismuth(III) oxide">Bismuth(III) oxide</a> (<a href="Bismuth" title="Bismuth">Bi</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Boron_trioxide" title="Boron trioxide">Boron trioxide</a> (<a href="Boron" title="Boron">B</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Californium(III)_oxide" title="Californium(III) oxide">Californium(III) oxide</a> (<a href="Californium" title="Californium">Cf</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Cerium(III)_oxide" title="Cerium(III) oxide">Cerium(III) oxide</a> (<a href="Cerium" title="Cerium">Ce</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Chromium(III)_oxide" title="Chromium(III) oxide">Chromium(III) oxide</a> (<a href="Chromium" title="Chromium">Cr</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Cobalt(III)_oxide" title="Cobalt(III) oxide">Cobalt(III) oxide</a> (<a href="Cobalt" title="Cobalt">Co</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Curium(III)_oxide" title="Curium(III) oxide">Curium(III) oxide</a> (<a href="Curium" title="Curium">Cm</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Dinitrogen_trioxide" title="Dinitrogen trioxide">Dinitrogen trioxide</a> (<a href="Nitrogen" title="Nitrogen">N</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Dysprosium(III)_oxide" title="Dysprosium(III) oxide">Dysprosium(III) oxide</a> (<a href="Dysprosium" title="Dysprosium">Dy</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Einsteinium(III)_oxide" title="Einsteinium(III) oxide">Einsteinium(III) oxide</a> (<a href="Einsteinium" title="Einsteinium">Es</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Erbium(III)_oxide" title="Erbium(III) oxide">Erbium(III) oxide</a> (<a href="Erbium" title="Erbium">Er</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Europium(III)_oxide" title="Europium(III) oxide">Europium(III) oxide</a> (<a href="Europium" title="Europium">Eu</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Gadolinium(III)_oxide" title="Gadolinium(III) oxide">Gadolinium(III) oxide</a> (<a href="Gadolinium" title="Gadolinium">Gd</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Gallium(III)_oxide" title="Gallium(III) oxide">Gallium(III) oxide</a> (<a href="Gallium" title="Gallium">Ga</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Gold(III)_oxide" title="Gold(III) oxide">Gold(III) oxide</a> (<a href="Gold" title="Gold">Au</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Holmium(III)_oxide" title="Holmium(III) oxide">Holmium(III) oxide</a> (<a href="Holmium" title="Holmium">Ho</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Indium(III)_oxide" title="Indium(III) oxide">Indium(III) oxide</a> (<a href="Indium" title="Indium">In</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Iron(III)_oxide" title="Iron(III) oxide">Iron(III) oxide</a> (<a href="Iron" title="Iron">Fe</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Lanthanum_oxide" title="Lanthanum oxide">Lanthanum oxide</a> (<a href="Lanthanum" title="Lanthanum">La</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Lutetium(III)_oxide" title="Lutetium(III) oxide">Lutetium(III) oxide</a> (<a href="Lutetium" title="Lutetium">Lu</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Manganese(III)_oxide" title="Manganese(III) oxide">Manganese(III) oxide</a> (<a href="Manganese" title="Manganese">Mn</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Neodymium(III)_oxide" title="Neodymium(III) oxide">Neodymium(III) oxide</a> (<a href="Neodymium" title="Neodymium">Nd</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Nickel(III)_oxide" title="Nickel(III) oxide">Nickel(III) oxide</a> (<a href="Nickel" title="Nickel">Ni</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Phosphorus_trioxide" title="Phosphorus trioxide">Phosphorus trioxide</a> (<a href="Phosphorus" title="Phosphorus">P</a><sub>4</sub>O<sub>6</sub>)</li>

<li><a href="Praseodymium(III)_oxide" title="Praseodymium(III) oxide">Praseodymium(III) oxide</a> (<a href="Praseodymium" title="Praseodymium">Pr</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Promethium(III)_oxide" title="Promethium(III) oxide">Promethium(III) oxide</a> (<a href="Promethium" title="Promethium">Pm</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Rhodium(III)_oxide" title="Rhodium(III) oxide">Rhodium(III) oxide</a> (<a href="Rhodium" title="Rhodium">Rh</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Samarium(III)_oxide" title="Samarium(III) oxide">Samarium(III) oxide</a> (<a href="Samarium" title="Samarium">Sm</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Scandium_oxide" title="Scandium oxide">Scandium oxide</a> (<a href="Scandium" title="Scandium">Sc</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Terbium(III)_oxide" title="Terbium(III) oxide">Terbium(III) oxide</a> (<a href="Terbium" title="Terbium">Tb</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Thallium(III)_oxide" title="Thallium(III) oxide">Thallium(III) oxide</a> (<a href="Thallium" title="Thallium">Tl</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Thulium(III)_oxide" title="Thulium(III) oxide">Thulium(III) oxide</a> (<a href="Thulium" title="Thulium">Tm</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Titanium(III)_oxide" title="Titanium(III) oxide">Titanium(III) oxide</a> (<a href="Titanium" title="Titanium">Ti</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Tungsten(III)_oxide" title="Tungsten(III) oxide">Tungsten(III) oxide</a> (<a href="Tungsten" title="Tungsten">W</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Vanadium(III)_oxide" title="Vanadium(III) oxide">Vanadium(III) oxide</a> (<a href="Vanadium" title="Vanadium">V</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Ytterbium(III)_oxide" title="Ytterbium(III) oxide">Ytterbium(III) oxide</a> (<a href="Ytterbium" title="Ytterbium">Yb</a><sub>2</sub>O<sub>3</sub>)</li>

<li><a href="Yttrium(III)_oxide" title="Yttrium(III) oxide">Yttrium(III) oxide</a> (<a href="Yttrium" title="Yttrium">Y</a><sub>2</sub>O<sub>3</sub>)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">+4 oxidation state</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Americium_dioxide" title="Americium dioxide">Americium dioxide</a> (<a href="Americium" title="Americium">Am</a>O<sub>2</sub>)</li>

<li><a href="Berkelium(IV)_oxide" title="Berkelium(IV) oxide">Berkelium(IV) oxide</a> (<a href="Berkelium" title="Berkelium">Bk</a>O<sub>2</sub>)</li>

<li><a href="Bromine_dioxide" title="Bromine dioxide">Bromine dioxide</a> (<a href="Bromine" title="Bromine">Br</a>O<sub>2</sub>)</li>

<li><a href="Californium_dioxide" class="mw-redirect" title="Californium dioxide">Californium dioxide</a> (<a href="Californium" title="Californium">Cf</a>O<sub>2</sub>)</li>

<li><a href="Carbon_dioxide" title="Carbon dioxide">Carbon dioxide</a> (<a href="Carbon" title="Carbon">C</a>O<sub>2</sub>)</li>

<li><a href="Carbon_trioxide" title="Carbon trioxide">Carbon trioxide</a> (<a href="Carbon" title="Carbon">C</a>O<sub>3</sub>)</li>

<li><a href="Cerium(IV)_oxide" title="Cerium(IV) oxide">Cerium(IV) oxide</a> (<a href="Cerium" title="Cerium">Ce</a>O<sub>2</sub>)</li>

<li><a href="Chlorine_dioxide" title="Chlorine dioxide">Chlorine dioxide</a> (<a href="Chlorine" title="Chlorine">Cl</a>O<sub>2</sub>)</li>

<li><a href="Chromium(IV)_oxide" title="Chromium(IV) oxide">Chromium(IV) oxide</a> (<a href="Chromium" title="Chromium">Cr</a>O<sub>2</sub>)</li>

<li><a href="Curium(IV)_oxide" title="Curium(IV) oxide">Curium(IV) oxide</a> (<a href="Curium" title="Curium">Cm</a>O<sub>2</sub>)</li>

<li><a href="Dinitrogen_tetroxide" title="Dinitrogen tetroxide">Dinitrogen tetroxide</a> (<a href="Nitrogen" title="Nitrogen">N</a><sub>2</sub>O<sub>4</sub>)</li>

<li><a href="Germanium_dioxide" title="Germanium dioxide">Germanium dioxide</a> (<a href="Germanium" title="Germanium">Ge</a>O<sub>2</sub>)</li>

<li><a href="Iodine_dioxide" title="Iodine dioxide">Iodine dioxide</a> (<a href="Iodine" title="Iodine">I</a>O<sub>2</sub>)</li>

<li><a href="Iridium_dioxide" class="mw-redirect" title="Iridium dioxide">Iridium dioxide</a> (<a href="Iridium" title="Iridium">Ir</a>O<sub>2</sub>)</li>

<li><a href="Hafnium(IV)_oxide" title="Hafnium(IV) oxide">Hafnium(IV) oxide</a> (<a href="Hafnium" title="Hafnium">Hf</a>O<sub>2</sub>)</li>

<li><a href="Lead_dioxide" title="Lead dioxide">Lead dioxide</a> (<a href="Lead" title="Lead">Pb</a>O<sub>2</sub>)</li>

<li><a href="Manganese_dioxide" title="Manganese dioxide">Manganese dioxide</a> (<a href="Manganese" title="Manganese">Mn</a>O<sub>2</sub>)</li>

<li><a href="Molybdenum_dioxide" title="Molybdenum dioxide">Molybdenum dioxide</a> (<a href="Molybdenum" title="Molybdenum">Mo</a>O<sub>2</sub>)</li>

<li><a href="Neptunium(IV)_oxide" title="Neptunium(IV) oxide">Neptunium(IV) oxide</a> (<a href="Neptunium" title="Neptunium">Np</a>O<sub>2</sub>)</li>

<li><a href="Nitrogen_dioxide" title="Nitrogen dioxide">Nitrogen dioxide</a> (<a href="Nitrogen" title="Nitrogen">N</a>O<sub>2</sub>)</li>

<li><a href="Niobium_dioxide" title="Niobium dioxide">Niobium dioxide</a> (<a href="Niobium" title="Niobium">Nb</a>O<sub>2</sub>)</li>

<li><a href="Osmium_dioxide" title="Osmium dioxide">Osmium dioxide</a> (<a href="Osmium" title="Osmium">Os</a>O<sub>2</sub>)</li>

<li><a href="Adams'_catalyst" title="Adams' catalyst">Platinum dioxide</a> (<a href="Platinum" title="Platinum">Pt</a>O<sub>2</sub>)</li>

<li><a href="Plutonium(IV)_oxide" title="Plutonium(IV) oxide">Plutonium(IV) oxide</a> (<a href="Plutonium" title="Plutonium">Pu</a>O<sub>2</sub>)</li>

<li><a href="Polonium_dioxide" title="Polonium dioxide">Polonium dioxide</a> (<a href="Polonium" title="Polonium">Po</a>O<sub>2</sub>)</li>

<li><a href="Praseodymium(IV)_oxide" title="Praseodymium(IV) oxide">Praseodymium(IV) oxide</a> (<a href="Praseodymium" title="Praseodymium">Pr</a>O<sub>2</sub>)</li>

<li><a href="Protactinium(IV)_oxide" title="Protactinium(IV) oxide">Protactinium(IV) oxide</a> (<a href="Protactinium" title="Protactinium">Pa</a>O<sub>2</sub>)</li>

<li><a href="Rhenium(IV)_oxide" title="Rhenium(IV) oxide">Rhenium(IV) oxide</a> (<a href="Rhenium" title="Rhenium">Re</a>O<sub>2</sub>)</li>

<li><a href="Rhodium(IV)_oxide" title="Rhodium(IV) oxide">Rhodium(IV) oxide</a> (<a href="Rhodium" title="Rhodium">Rh</a>O<sub>2</sub>)</li>

<li><a href="Ruthenium(IV)_oxide" title="Ruthenium(IV) oxide">Ruthenium(IV) oxide</a> (<a href="Ruthenium" title="Ruthenium">Ru</a>O<sub>2</sub>)</li>

<li><a href="Silicon_dioxide" title="Silicon dioxide">Silicon dioxide</a> (<a href="Silicon" title="Silicon">Si</a>O<sub>2</sub>)</li>

<li><a href="Sulfur_dioxide" title="Sulfur dioxide">Sulfur dioxide</a> (<a href="Sulfur" title="Sulfur">S</a>O<sub>2</sub>)</li>

<li><a href="Technetium(IV)_oxide" title="Technetium(IV) oxide">Technetium(IV) oxide</a> (<a href="Technetium" title="Technetium">Tc</a>O<sub>2</sub>)</li>

<li><a href="Tellurium_dioxide" title="Tellurium dioxide">Tellurium dioxide</a> (<a href="Tellurium" title="Tellurium">Te</a>O<sub>2</sub>)</li>

<li><a href="Terbium(IV)_oxide" title="Terbium(IV) oxide">Terbium(IV) oxide</a> (<a href="Terbium" title="Terbium">Tb</a>O<sub>2</sub>)</li>

<li><a href="Thorium_dioxide" title="Thorium dioxide">Thorium dioxide</a> (<a href="Thorium" title="Thorium">Th</a>O<sub>2</sub>)</li>

<li><a href="Tin(IV)_oxide" title="Tin(IV) oxide">Tin dioxide</a> (<a href="Tin" title="Tin">Sn</a>O<sub>2</sub>)</li>

<li><a href="Titanium_dioxide" title="Titanium dioxide">Titanium dioxide</a> (<a href="Titanium" title="Titanium">Ti</a>O<sub>2</sub>)</li>

<li><a href="Tungsten(IV)_oxide" title="Tungsten(IV) oxide">Tungsten(IV) oxide</a> (<a href="Tungsten" title="Tungsten">W</a>O<sub>2</sub>)</li>

<li><a href="Uranium_dioxide" title="Uranium dioxide">Uranium dioxide</a> (<a href="Uranium" title="Uranium">U</a>O<sub>2</sub>)</li>

<li><a href="Vanadium(IV)_oxide" title="Vanadium(IV) oxide">Vanadium(IV) oxide</a> (<a href="Vanadium" title="Vanadium">V</a>O<sub>2</sub>)</li>

<li><a href="Xenon_dioxide" title="Xenon dioxide">Xenon dioxide</a> (<a href="Xenon" title="Xenon">Xe</a>O<sub>2</sub>)</li>

<li><a href="Zirconium_dioxide" title="Zirconium dioxide">Zirconium dioxide</a> (<a href="Zirconium" title="Zirconium">Zr</a>O<sub>2</sub>)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">+5 oxidation state</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Antimony_pentoxide" title="Antimony pentoxide">Antimony pentoxide</a> (<a href="Antimony" title="Antimony">Sb</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Arsenic_pentoxide" title="Arsenic pentoxide">Arsenic pentoxide</a> (<a href="Arsenic" title="Arsenic">As</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Bismuth_pentoxide" title="Bismuth pentoxide">Bismuth pentoxide</a> (<a href="Bismuth" title="Bismuth">Bi</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Dinitrogen_pentoxide" title="Dinitrogen pentoxide">Dinitrogen pentoxide</a> (<a href="Nitrogen" title="Nitrogen">N</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Diuranium_pentoxide" title="Diuranium pentoxide">Diuranium pentoxide</a> (<a href="Uranium" title="Uranium">U</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Neptunium(V)_oxide" title="Neptunium(V) oxide">Neptunium(V) oxide</a> (<a href="Neptunium" title="Neptunium">Np</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Niobium_pentoxide" title="Niobium pentoxide">Niobium pentoxide</a> (<a href="Niobium" title="Niobium">Nb</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Phosphorus_pentoxide" title="Phosphorus pentoxide">Phosphorus pentoxide</a> (<a href="Phosphorus" title="Phosphorus">P</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Protactinium(V)_oxide" title="Protactinium(V) oxide">Protactinium(V) oxide</a> (<a href="Protactinium" title="Protactinium">Pa</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Tantalum_pentoxide" title="Tantalum pentoxide">Tantalum pentoxide</a> (<a href="Tantalum" title="Tantalum">Ta</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Tungsten_pentoxide" title="Tungsten pentoxide">Tungsten pentoxide</a> (<a href="Tungsten" title="Tungsten">W</a><sub>2</sub>O<sub>5</sub>)</li>

<li><a href="Vanadium(V)_oxide" title="Vanadium(V) oxide">Vanadium(V) oxide</a> (<a href="Vanadium" title="Vanadium">V</a><sub>2</sub>O<sub>5</sub>)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">+6 oxidation state</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Chromium_trioxide" title="Chromium trioxide">Chromium trioxide</a> (<a href="Chromium" title="Chromium">Cr</a>O<sub>3</sub>)</li>

<li><a href="Molybdenum_trioxide" title="Molybdenum trioxide">Molybdenum trioxide</a> (<a href="Molybdenum" title="Molybdenum">Mo</a>O<sub>3</sub>)</li>

<li><a href="Polonium_trioxide" title="Polonium trioxide">Polonium trioxide</a> (<a href="Polonium" title="Polonium">Po</a>O<sub>3</sub>)</li>

<li><a href="Rhenium_trioxide" title="Rhenium trioxide">Rhenium trioxide</a> (<a href="Rhenium" title="Rhenium">Re</a>O<sub>3</sub>)</li>

<li><a href="Selenium_trioxide" title="Selenium trioxide">Selenium trioxide</a> (<a href="Selenium" title="Selenium">Se</a>O<sub>3</sub>)</li>

<li><a href="Sulfur_trioxide" title="Sulfur trioxide">Sulfur trioxide</a> (<a href="Sulfur" title="Sulfur">S</a>O<sub>3</sub>)</li>

<li><a href="Tellurium_trioxide" title="Tellurium trioxide">Tellurium trioxide</a> (<a href="Tellurium" title="Tellurium">Te</a>O<sub>3</sub>)</li>

<li><a href="Tungsten_trioxide" title="Tungsten trioxide">Tungsten trioxide</a> (<a href="Tungsten" title="Tungsten">W</a>O<sub>3</sub>)</li>

<li><a href="Uranium_trioxide" title="Uranium trioxide">Uranium trioxide</a> (<a href="Uranium" title="Uranium">U</a>O<sub>3</sub>)</li>

<li><a href="Xenon_trioxide" title="Xenon trioxide">Xenon trioxide</a> (<a href="Xenon" title="Xenon">Xe</a>O<sub>3</sub>)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">+7 oxidation state</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Dichlorine_heptoxide" title="Dichlorine heptoxide">Dichlorine heptoxide</a> (<a href="Chlorine" title="Chlorine">Cl</a><sub>2</sub>O<sub>7</sub>)</li>

<li><a href="Manganese_heptoxide" title="Manganese heptoxide">Manganese heptoxide</a> (<a href="Manganese" title="Manganese">Mn</a><sub>2</sub>O<sub>7</sub>)</li>

<li><a href="Rhenium(VII)_oxide" title="Rhenium(VII) oxide">Rhenium(VII) oxide</a> (<a href="Rhenium" title="Rhenium">Re</a><sub>2</sub>O<sub>7</sub>)</li>

<li><a href="Technetium(VII)_oxide" title="Technetium(VII) oxide">Technetium(VII) oxide</a> (<a href="Technetium" title="Technetium">Tc</a><sub>2</sub>O<sub>7</sub>)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">+8 oxidation state</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Iridium_tetroxide" title="Iridium tetroxide">Iridium tetroxide</a> (<a href="Iridium" title="Iridium">Ir</a>O<sub>4</sub>)</li>

<li><a href="Osmium_tetroxide" title="Osmium tetroxide">Osmium tetroxide</a> (<a href="Osmium" title="Osmium">Os</a>O<sub>4</sub>)</li>

<li><a href="Ruthenium_tetroxide" title="Ruthenium tetroxide">Ruthenium tetroxide</a> (<a href="Ruthenium" title="Ruthenium">Ru</a>O<sub>4</sub>)</li>

<li><a href="Xenon_tetroxide" title="Xenon tetroxide">Xenon tetroxide</a> (<a href="Xenon" title="Xenon">Xe</a>O<sub>4</sub>)</li>

<li><a href="Hassium_tetroxide" title="Hassium tetroxide">Hassium tetroxide</a> (<a href="Hassium" title="Hassium">Hs</a>O<sub>4</sub>)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Oxocarbon" title="Oxocarbon">Oxocarbon</a></li>

<li><a href="Suboxide" title="Suboxide">Suboxide</a></li>

<li><a href="Oxyanion" title="Oxyanion">Oxyanion</a></li>

<li><a href="Ozonide" title="Ozonide">Ozonide</a></li>

<li><a href="Peroxide" title="Peroxide">Peroxide</a></li>

<li><a href="Superoxide" title="Superoxide">Superoxide</a></li>

<li><a href="Oxypnictide" title="Oxypnictide">Oxypnictide</a></li></ul>

</div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div>Oxides are sorted by <a href="Oxidation_state" title="Oxidation state">oxidation state</a>.

Category:Oxides</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2024-06-21" href="https://en.wikipedia.org/wiki/?title=Selenium_dioxide&oldid=1230294219">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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