Magnesium fluoride
Names | |
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Other names
Sellaite
Irtran-1 | |
Identifiers | |
3D model (
JSmol ) |
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ChemSpider | |
ECHA InfoCard
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100.029.086 |
EC Number |
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PubChem CID
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RTECS number
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
MgF2 | |
Molar mass | 62.3018 g/mol |
Appearance | White tetragonal crystals
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Density | 3.148 g/cm3 |
Melting point | 1,263 °C (2,305 °F; 1,536 K) |
Boiling point | 2,260 °C (4,100 °F; 2,530 K) |
0.013 g/(100 mL) | |
Solubility product (Ksp)
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5.16⋅10−11 |
Solubility |
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−22.7⋅10−6 cm3/mol | |
Refractive index (nD)
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1.37397 |
Structure | |
Rutile (tetragonal), tP6 | |
P42/mnm, No. 136 | |
Thermochemistry | |
Heat capacity (C)
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61.6 J⋅mol−1⋅K−1 |
Std molar
entropy (S⦵298) |
57.2 J⋅mol−1⋅K−1 |
Std enthalpy of (ΔfH⦵298)formation |
−1124.2 kJ⋅mol−1 |
Gibbs free energy (ΔfG⦵)
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−1071 kJ/mol |
Hazards[2][3] | |
GHS labelling: | |
Warning | |
H303, H315, H319, H335 | |
P261, P304+P340, P305+P351+P338, P405 | |
NFPA 704 (fire diamond) | |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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2330[clarification needed] (rat, oral) |
Safety data sheet (SDS) | ChemicalBook |
Related compounds | |
Other anions
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Other cations
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Magnesium fluoride is an ionically bonded inorganic compound with the formula MgF2. The compound is a white crystalline salt and is transparent over a wide range of wavelengths, with commercial uses in optics that are also used in space telescopes. It occurs naturally as the rare mineral sellaite.
Production
Magnesium fluoride is prepared from magnesium oxide with sources of hydrogen fluoride such as ammonium bifluoride:
- MgO + [NH4]HF2 → MgF2 + NH3 + H2O
Related metathesis reactions are also feasible:
- Mg(OH)2 + CuF2 → MgF2 + Cu(OH)2
Structure
The compound crystallizes as
Magnesium coordination | Fluorine coordination |
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In the gas phase,
Uses
Optics
Magnesium fluoride is
Magnesium fluoride is tough and polishes well but is slightly
Safety
Chronic exposure to magnesium fluoride may affect the skeleton, kidneys, central nervous system, respiratory system, eyes and skin, and may cause or aggravate attacks of asthma.[9]
References
- ^
W.M. Haynes, ed. (2016), "Physical Constants of Inorganic Compounds", Handbook of Chemistry and Physics (97th ed.), CRC Press, pp. 4–71 (789), ISBN 978-1-4987-5429-3
- ^ "Magnesium Fluoride Material Safety Data Sheet". Science Labs. May 21, 2013. Retrieved October 13, 2017.
- ^ "Magnesium fluoride". CAS DataBase List. ChemicalBook. Retrieved October 13, 2017.
- ^ ISBN 978-0-19-965763-6.
- ^ ISBN 978-0-08-037941-8.
- ^ ISBN 978-3527306732.
- .
- ^ "Magnesium Fluoride Material Safety Data Sheet". ESPI Metals. August 2004. Archived from the original on 2017-10-28. Retrieved October 13, 2017.