Editing Silicon dioxide (section)

{{Short description|Oxide of silicon}}
{{Redirect|Silica}}
{{cs1 config|name-list-style=vanc}}

{{Chembox
|Verifiedfields = changed
|Watchedfields  = changed
|verifiedrevid  = 476993639
|ImageFile1 = Sample of silicon dioxide.jpg
|ImageCaption1 = A sample of silicon dioxide
|ImageFile1_Ref = {{Chemboximage|correct|??}}
|ImageNameR1 = A sample of silicon dioxide as sand in a dune
|ImageCaptionR1 = Silicon dioxide as sand
|IUPACName = Silicon dioxide
|OtherNames = {{unbulleted list |Quartz |Silica |Silicic oxide |Silicon(IV) oxide |Crystalline silica |Pure Silica |Silicea |Silica sand }}
|Section1 = {{Chembox Identifiers
|CASNo = 7631-86-9
|CASNo_Ref = {{cascite|correct|CAS}}
|PubChem = 24261
|ChemSpiderID = 22683
|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
|UNII = ETJ7Z6XBU4
|UNII_Ref = {{fdacite|correct|FDA}}
|EINECS = 231-545-4
|KEGG = C16459
|KEGG_Ref = {{keggcite|correct|kegg}}
|MeSHName = Silicon+dioxide
|ChEBI_Ref = {{ebicite|correct|EBI}}
|ChEBI = 30563
|RTECS = VV7565000
|Gmelin = 200274
|StdInChI = 1S/O2Si/c1-3-2
|StdInChI_Ref = {{stdinchicite|correct|chemspider}}
|StdInChIKey = VYPSYNLAJGMNEJ-UHFFFAOYSA-N
|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
}}
|Section2 = {{Chembox Properties
|Formula =SiO<sub>2</sub>
|MolarMass = 60.08 g/mol
|Appearance = Transparent or white
|Density = 2.648 (α-quartz), 2.196 (amorphous) g·cm<sup>−3</sup><ref name=b92>{{RubberBible92nd}}</ref>
|MeltingPtC = 1713
|MeltingPt_notes = (amorphous)<ref name=b92/>{{rp|page=4.88}}
|BoilingPtC = 2950
|BoilingPt_ref = <ref name=b92/>
|RefractIndex = 1.544 ([[Birefringence|o]]), 1.553 (e)<ref name=b92/>{{rp|page=4.143}}
|ThermalConductivity = 12 (<nowiki>||</nowiki> c-axis), 6.8 (⊥ c-axis), 1.4 (am.) W/(m⋅K)<ref name=b92/>{{rp|page=12.213}}
|MagSus = &minus;29.6·10<sup>−6</sup> cm<sup>3</sup>/mol
}}
|Section3 = {{Chembox Hazards
|NFPA-H = 0
|NFPA-F = 0
|NFPA-R = 0
|IDLH = 3000 mg/m<sup>3</sup> (amorphous)<ref name=PGCH0552>{{PGCH|0552}}</ref><br/>Ca [25 mg/m<sup>3</sup> (cristobalite, tridymite); 50 mg/m<sup>3</sup> (quartz)]<ref name=PGCH0682>{{PGCH|0682}}</ref>
|REL = TWA 6 mg/m<sup>3</sup> (amorphous)<ref name=PGCH0552/><br/>Ca TWA 0.05 mg/m<sup>3</sup><ref name=PGCH0682/>
|PEL = TWA 20 mppcf (80 mg/m<sup>3</sup>/%SiO<sub>2</sub>) (amorphous)<ref name=PGCH0552/>
}}
|Section4 = {{Chembox Related
|OtherFunction_label = diones
|OtherFunction = [[Carbon dioxide]]<br/>[[Germanium dioxide]]<br/>[[Tin dioxide]]<br/>[[Lead dioxide]]
|OtherCompounds = [[Silicon monoxide]]<br/>[[Silicon disulfide]]
}}
|Section5 = {{Chembox Thermochemistry
|DeltaHf = −911&nbsp;kJ·mol<sup>−1</sup><ref name=b1>{{cite book| author = Zumdahl, Steven S.|title =Chemical Principles 6th Ed.| publisher = Houghton Mifflin Company| year = 2009| isbn = 978-0-618-94690-7|page=A22}}</ref>
|Entropy = 42&nbsp;J·mol<sup>−1</sup>·K<sup>−1</sup><ref name=b1/>
}}
}}

'''Silicon dioxide''', also known as '''silica''', is an [[oxide]] of [[silicon]] with the [[chemical formula]] {{chem2|SiO2}}, commonly found in nature as [[quartz]].<ref>{{cite book|title=The Chemistry of Silica|vauthors=Iler RK|publisher=Wiley|year=1979|isbn=9780471024040|location=New York}}</ref><ref name="Fern">{{cite journal|vauthors=Fernández LD, Lara E, Mitchell EA|year=2015|title=Checklist, diversity and distribution of testate amoebae in Chile|url=http://doc.rero.ch/record/257075/files/Fernandez_L._D.-Checklist_diversity_distribution_of_testate_amoebae-20150922.pdf |archive-url=https://ghostarchive.org/archive/20221010/http://doc.rero.ch/record/257075/files/Fernandez_L._D.-Checklist_diversity_distribution_of_testate_amoebae-20150922.pdf |archive-date=2022-10-10 |url-status=live|journal=European Journal of Protistology|volume=51|issue=5|pages=409–24|doi=10.1016/j.ejop.2015.07.001|pmid=26340665}}</ref> In many parts of the world, silica is the major constituent of [[sand]]. Silica is one of the most complex and abundant families of [[material]]s, existing as a compound of several [[mineral]]s and as a synthetic product. Examples include [[fused quartz]], [[fumed silica]], [[opal]], and [[aerogel]]s. It is used in [[structural material]]s, [[microelectronics]], and as components in the food and pharmaceutical industries. All forms are white or colorless, although impure samples can be colored.

Silicon dioxide is a common fundamental constituent of [[glass]].