Back Silikondioksied Afrikaans Silica AN ثنائي أكسيد السيليكون Arabic Kremni oksidi(IV) Azerbaijani سیلیسیوم دیاوکسید AZB Силициев диоксид Bulgarian সিলিকন ডাই অক্সাইড Bengali/Bangla Silicij-dioksid BS Diòxid de silici Catalan Oxid křemičitý Czech
 A sample of silicon dioxide
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| Names | |
|---|---|
| IUPAC name
Silicon dioxide
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Other names
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| Identifiers | |
| ChEBI | |
| ChemSpider | |
| ECHA InfoCard | 100.028.678 |
| EC Number |
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| E number | E551 (acidity regulators, ...) |
| 200274 | |
| KEGG | |
| MeSH | Silicon+dioxide |
PubChem CID
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| RTECS number |
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| SiO2 | |
| Molar mass | 60.08 g/mol |
| Appearance | Transparent or white |
| Density | 2.648 (α-quartz), 2.196 (amorphous) g·cm−3[1] |
| Melting point | 1,713 °C (3,115 °F; 1,986 K) (amorphous)[1]: 4.88 |
| Boiling point | 2,950 °C (5,340 °F; 3,220 K)[1] |
| −29.6·10−6 cm3/mol | |
| Thermal conductivity | 12 (|| c-axis), 6.8 (⊥ c-axis), 1.4 (am.) W/(m⋅K)[1]: 12.213 |
Refractive index (nD)
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1.544 (o), 1.553 (e)[1]: 4.143 |
| Hazards | |
| NFPA 704 (fire diamond) | |
| NIOSH (US health exposure limits): | |
PEL (Permissible)
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TWA 20 mppcf (80 mg/m3/%SiO2) (amorphous)[2] |
REL (Recommended)
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TWA 6 mg/m3 (amorphous)[2] Ca TWA 0.05 mg/m3[3] |
IDLH (Immediate danger)
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3000 mg/m3 (amorphous)[2] Ca [25 mg/m3 (cristobalite, tridymite); 50 mg/m3 (quartz)][3] |
| Related compounds | |
Related diones
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Carbon dioxide Germanium dioxide Tin dioxide Lead dioxide |
Related compounds
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Silicon monoxide Silicon disulfide |
| Thermochemistry | |
Std molar
entropy (S⦵298) |
42 J·mol−1·K−1[4] |
Std enthalpy of
formation (ΔfH⦵298) |
−911 kJ·mol−1[4] |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula SiO2, commonly found in nature as quartz.[5][6] In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant families of materials, existing as a compound of several minerals and as a synthetic product. Examples include fused quartz, fumed silica, opal, and aerogels. It is used in structural materials, 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.
- ^ a b c d e Haynes WM, ed. (2011). CRC Handbook of Chemistry and Physics (92nd ed.). Boca Raton, Florida: CRC Press. ISBN 1-4398-5511-0.
- ^ a b c NIOSH Pocket Guide to Chemical Hazards. "#0552". National Institute for Occupational Safety and Health (NIOSH).
- ^ a b NIOSH Pocket Guide to Chemical Hazards. "#0682". National Institute for Occupational Safety and Health (NIOSH).
- ^ a b Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. p. A22. ISBN 978-0-618-94690-7.
- ^ Iler RK (1979). The Chemistry of Silica. New York: Wiley. ISBN 9780471024040.
- ^ Fernández LD, Lara E, Mitchell EA (2015). "Checklist, diversity and distribution of testate amoebae in Chile" (PDF). European Journal of Protistology. 51 (5): 409–24. doi:10.1016/j.ejop.2015.07.001. PMID 26340665. Archived (PDF) from the original on 2022-10-10.