Potassium fluorosilicate appears as a white, odorless crystalline powder. Denser than water. Contact may cause irritation to skin, eyes, and mucous membranes. May be toxic by ingestion. Used to make other chemicals.
POTASSIUM HEXAFLUOROSILICATE [MI]SILICATE, HEXAFLUORO-, DIPOTASSIUMEC 240-896-2RefChem:175487FLUOSILICATE DE POTASSIUMDipotassium hexafluorosilicate(2)FLUOROSILICATE DE POTASSIUMSILICOFLUORURE DE POTASSIUM
Database identifiers
CAS
16871-90-2
Properties
Computed structural properties
Topological polar surface area
0 Ų
Hydrogen bond donors
0
Hydrogen bond acceptors
7
Rotatable bonds
0
Heavy atoms
9
Formal charge
0
Complexity
62.7
Experimental & physicochemical properties
Chemical ClassesMetals -> Metals, Inorganic Compounds
CosmeticsAntiplaque; Oral care
Density · 2 items
Relative density (water = 1): 2.3
2.27 @25 °C
SolubilitySolubility in water, g/100ml at 20 °C: 0.18 (poor)
Physical Description · 4 items
Potassium fluorosilicate appears as a white, odorless crystalline powder. Denser than water. Contact may cause irritation to skin, eyes, and mucous membranes. May be toxic by ingestion. Used to make other chemicals.
Dry Powder
White solid; [Merck Index] White powder; [Alfa Aesar MSDS]
WHITE CRYSTALS OR FINE POWDER.
Physicochemical properties
Melting point
°Cd ec.)
Boiling point
dec
Density
2.665 g/mL · 2.665 g/mL at 25 °C(lit.)
vapor pressure
0.01 Pa · 0.01Pa
refractive index
1.3991 · 1.3991
Safety & regulation
Safety information is for reference only and does not replace the supplier’s Safety Data Sheet (SDS), applicable regulations, or professional assessment.
GHS classification
GHS Classification · 6 items
Danger
H301: Toxic if swallowed [Danger Acute toxicity, oral]
P261, P262, P264, P270, P271, P280, P301+P316, P302+P352, P304+P340, P316, P321, P330, P361+P364, P403+P233, P405, and P501 (click each P-code to see the statement)
This chemical does not meet GHS hazard criteria for 9.2% (11 of 119) of reports.
Danger
H301 (90.8%): Toxic if swallowed [Danger Acute toxicity, oral]
Hazard information
Regulatory Information · 5 items
Chemical: Silicate(2-), hexafluoro-, dipotassium
Silicate(2-), hexafluoro-, potassium (1:2) is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Silicate(2-), hexafluoro-, potassium (1:2) are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)
Potassium hexafluorosilicate: Does not have an individual approval but may be used under an appropriate group standard
The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)
Other Safety InformationIMAP assessments - Hexafluorosilicate salts: Human health tier II assessment
DOT LabelPoison
Fire Hazards · 2 items
Excerpt from ERG Guide 151 [Substances - Toxic (Non-Combustible)]:
Not combustible. Gives off irritating or toxic fumes (or gases) in a fire.
Health HazardsExcerpt from ERG Guide 151 [Substances - Toxic (Non-Combustible)]:
Chemistry & industry
Uses & manufacturing
Uses · 3 items
Used to make opalescent glass, in porcelain enamels, insecticides, and aluminum metallurgy; [Merck Index]
Aluminum Producing [Category: Industry]
Ceramics making [Category: Hobbies]
U.S. Production2023: 407,000 lb
Consumer UsesNot Known or Reasonably Ascertainable
Industry UsesAbrasives
Use ClassificationCosmetics -> Antiplaque; Oral care
General Manufacturing Information · 2 items
Not Known or Reasonably Ascertainable
Silicate(2-), hexafluoro-, potassium (1:2): ACTIVE
Applications · 4 items
DescriptionAs a type of fluorosilicate, potassium fluorosilicate can be used as fluoridizing agents for water supplies, in the production of synthetic cryolite, and in metal plating. Potassium fluorosilicate can be used as oral care ingredient, as a fluxing ingredient in porcelain enamels, and as wood preservative elements. Potassium fluorosilicate can also be used for the manufacture of ceramic materials and optical glasses.
UsesPotassium hexafluorosilicate is used in the production of porceleins. It is also used for the preservation of timber. It is involved in the manufacturing of ceramics, aluminum and magnesium smelting. In addition, it is used as an intermediate in the manufacturing of optical glass.
UsesIn the manufacture of opalescent glass, in porcelain enamels, in insecticides. Also used in aluminum metallurgy.
General DescriptionA white, odorless crystalline powder. Denser than water. Contact may cause irritation to skin, eyes, and mucous membranes. May be toxic by ingestion. Used to make other chemicals.
Causes flaccid paralysis, ataxia, and muscle contraction in oral lethal-dose studies of mice and rats; [RTECS] Hydrolyzed by hot water producing potassium fluoride, hydrogen fluoride, and silicic acid; A severe irritant; [Merck Index] A skin, eye, and respiratory tract irritant; May have effects on calcium metabolism; Chronic exposure may cause fluorosis; [ICSC] Forms hydrofluoric acid when dissolved in water; An irritant; Toxic by ingestion, inhalation, and skin absorption; [Alfa Aesar MSDS] See Sodium hexafluorosilicate.
Reactive GroupSalts, Basic
EC ClassificationSymbol: T; R: 23/24/25; S: (1/2)-26-45; Note: A
UN ClassificationUN Hazard Class: 6.1; UN Pack Group: III
Reactivity Profile · 1 item
Solutions of potassium fluorosilicate may contain some hydrofluoric acid, which can cause severe chemical burns and is one of the few materials that can etch glass. Unlike other halide ions, fluoride is quite reactive, acting as a weak base and participating in some unique reactions. In particular, fluorides react strongly with compounds containing calcium, magnesium, or silicon ions, which means that solutions containing soluble fluorides are corrosive to both living tissue and glass.
Chemical DangersDecomposes on heating. This produces toxic and corrosive fumes including fluorine. Reacts with acids. This produces corrosive hydrogen fluoride (see ICSC 0283).
Packaging and LabellingDo not transport with food and feedstuffs.
Safety & protection
Fire Fighting · 2 items
Excerpt from ERG Guide 151 [Substances - Toxic (Non-Combustible)]:
In case of fire in the surroundings, use appropriate extinguishing media.
First Aid Measures · 4 items
Fresh air, rest. Refer for medical attention.
Remove contaminated clothes. Rinse skin with plenty of water or shower.
First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.
Rinse mouth. Do NOT induce vomiting. Refer immediately for medical attention.
First AidExcerpt from ERG Guide 151 [Substances - Toxic (Non-Combustible)]:
Safe StorageSeparated from acids and food and feedstuffs.
Exposure Control and Personal Protection · 2 items
Biological Exposure Indices (BEI) [ACGIH] - Fluorides in urine = 2 mg/L prior to shift or 3 mg/L at end of shift; (Repeated measurements recommended.)
1.0 [mg/m3], inhalable fraction, as F[German Research Foundation (DFG)]
Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Sweep spilled substance into covered sealable containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations.
Isolation and EvacuationExcerpt from ERG Guide 151 [Substances - Toxic (Non-Combustible)]:
Eye PreventionWear safety goggles or eye protection in combination with breathing protection if powder.
Inhalation RiskA harmful concentration of airborne particles can be reached quickly when dispersed.
