Substance profile
Fluorosilicic acid
Fluorosilicic acid is a transparent, colorless, fuming liquid with a sour, pungent odor.
01 · Identification
What Fluorosilicic acid is
Fluorosilicic acid is a transparent, colorless, fuming liquid with a sour, pungent odor. Its molecular formula is F6H2Si and its molecular weight is 144.091 g/mol. It boils at 100 °C, melts at -20 °C.
Under the GHS it carries the signal word Danger. It is classed as corrosives.
Other names for Fluorosilicic acid
- fluorosilicic acid ... %
02 · GHS classification
Hazards and label elements
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
| Code | Hazard statement |
|---|---|
| H314 | Causes severe skin burns and eye damage. |
03 · Physical and chemical properties
Fluorosilicic acid properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 100 °C (212 °F) | at 760 mmHg | CAMEO |
| Decomposes. (USCG, 1999) | decomposes | CAMEO | |
| Melting point | -20 °C (-4 °F) | CAMEO | |
| Density | 1.25 g/cm³ | CAMEO | |
| 1.4634 g/cm³ | at 25 °C | HSDB | |
| 1.3 g/cm³ | at 25 °C, approx. | CAMEO | |
| Solubility | DECOMP AT MP; DELIQUESCENT; WHITE CRYSTALS; SOL IN ALKALI; SOL IN COLD AND HOT WATER | DIHYDRATE | HSDB |
| SOL IN COLD & HOT WATER; SLIGHTLY IN ALKALI | HSDB | ||
| Solubility in water: miscible | ICSC | ||
| Corrosivity | Attacks glass and stoneware | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling Fluorosilicic acid
Storage conditions
The more concentrated solution (but not the anhydrous liquid) can be stored in glass, although some etching will take place around the surface. Usually stored in iron containers.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
Will react with water or steam to produce toxic and corrosive fumes.
Source: Hazardous Substances Data Bank (HSDB)
Planning storage for a mix of chemicals? Check Fluorosilicic acid in the storage compatibility matrix →