Sodium fluorosilicate
Unit cell of the compound
Unit cell of sodium hexafluoridosilicate
Names
Preferred IUPAC name
Sodium fluorosilicate
Systematic IUPAC name
Sodium hexafluoridosilicate(2–) [1]
Other names
Disodium hexafluorosilicate/sodium fluosilicate/sodium silicofluoride
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.037.198 Edit this at Wikidata
EC Number
  • 240-934-8
RTECS number
  • VV8410000
UNII
UN number 2674
  • InChI=1S/F6Si.2Na/c1-7(2,3,4,5)6;;/q-2;2*+1
    Key: TWGUZEUZLCYTCG-UHFFFAOYSA-N
  • [Na+].[Na+].F[Si--](F)(F)(F)(F)F
Properties
Na2[SiF6]
Molar mass 188 g/mol
Appearance white granular powder
Odor odorless
Density 2.7 g/cm3
0.64 g/100 mL (20 °C)
1.27 g/100 mL (50 °C)
2.45 g/100 mL (100 °C)
Solubility insoluble in alcohol
1.312
Structure[2]
trigonal
P321
a = 8.859, c = 5.038
4
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
0
0
Lethal dose or concentration (LD, LC):
70 mg/kg (mouse, oral)
125 mg/kg (rabbit, oral)[3]
Related compounds
Other cations
 Ammonium hexafluorosilicate

Fluorosilicic acid

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Sodium fluorosilicate is a compound with the chemical formula Na2[SiF6]. Unlike other sodium salts, it has a low solubility in water.

Natural occurrence

Sodium hexafluorosilicate occurs naturally as the rare mineral malladrite found within some volcanic fumaroles.[4]

Manufacturing

Sodium fluorosilicate is made by neutralizing fluorosilicic acid with sodium chloride or sodium sulfate.

H2[SiF6] + 2 NaCl → Na2[SiF6] + 2 HCl

Possible application

It is used in some countries as additives for water fluoridation, opal glass raw material, ore refining, or other fluoride chemical (like sodium fluoride, magnesium silicofluoride, cryolite, aluminum fluoride) production.[5]

See also

References

  1. ^ "Parent Hydride Names and Substitutive Nomenclature". Nomenclature of Inorganic Chemistry, IUPAC Recommendations 2005 (PDF). RSC Publishing. 2005. pp. 114–135.
  2. ^ Allan Zalkin, J. D. Forrester, David H. Templeton (1964). "The Crystal Structure of Sodium Fluorosilicate". Acta Crystallographica. 17 (11): 1408–1412. Bibcode:1964AcCry..17.1408Z. doi:10.1107/S0365110X64003516.((cite journal)): CS1 maint: multiple names: authors list (link)
  3. ^ "Fluorides (as F)". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  4. ^ "Malladrite".
  5. ^ "PUB". Archived from the original on 2009-03-26. Retrieved 2009-08-10.
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