Potassium silicate
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| Names | |
|---|---|
| Preferred IUPAC name
Potassium metasilicate | |
| Other names
Liquid glass Waterglass | |
| Identifiers | |
1312-76-1  | |
| 3D model (Jmol) | Interactive image |
| ChemSpider | 59585  |
| ECHA InfoCard | 100.029.989 |
| EC Number | 233-001-1 |
| E number | E560 (acidity regulators, ...) |
| PubChem | 66200 |
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| Properties | |
| K2O3Si | |
| Molar mass | 154.28 g·mol−1 |
| Appearance | White crystals |
| Hazards | |
| EU classification (DSD) |
Corrosive (C), Irritant (Xi) |
| R-phrases | R34, R37 |
| S-phrases | (S1/2), S13, S24/25, S36/37/39, S45 |
| NFPA 704 | |
| Related compounds | |
| Other anions |
Potassium carbonate Potassium germanate Potassium stannate Potassium plumbate |
| Other cations |
Sodium silicate |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| verify (what is ?) | |
| Infobox references | |
Potassium silicate is the name for a family of inorganic compounds. The most common potassium silicate has the formula K2SiO3, samples of which contain varying about of water. These are white solids or colorless solution.[1]
Synthesis, structure, reactions
Potassium silicate can be synthesized in the laboratory by treating silica with potassium hydroxide, according to this idealized equation:
These solutions are highly alkaline. Addition of acids causes the reformation of silica.
K2SiO3 adopts a chain or cyclic structures with interlinked SiO32- monomers. Each Si is tetrahedral.
Uses
Woodwork protection against fire
Impregnation of wood with a potassium silicate solution is an easy and low cost way for rendering the woodwork of houses secure against catching fire. The woodwork is first saturated with a diluted and nearly neutral solution of potash silicate. After drying, one or two coats of a more concentrated solution are usually applied.[2]
Horticulture
In horticulture, potassium silicate is used as a soluble source of potassium and silicon. It makes the growing medium more alkaline.
It is also used as a supplement (in conjunction with normal fertilizer) for the numerous benefits that increasing the availability of silicon compounds has. Silicon-containing compounds are valuable to a plant, and serve to support the plant. Stems thicken, the plant becomes more tolerant to drought and resists wilting, and the plant gets larger leaves and fruit (because the stem can support more weight).
Industrial uses
Some metal cleaning formulations use potassium silicate, which also serves as a corrosion inhibitor.[3] It also finds various uses in the fabrication of welding rods or even of cosmetics.
Safety
Potassium silicate is strongly alkaline.
See also
References
- ↑ Gerard Lagaly, Werner Tufar, A. Minihan, A. Lovell "Silicates" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, 2005. doi:10.1002/14356007.a23_661
- ↑ Cobleigh, Rolfe (1909). Handy farm devices and how to make them. Part II: Worth knowing to render wood fireproof. New York: Orange Judd.
- ↑ Elmore AR (2005). "Final report on the safety assessment of potassium silicate, sodium metasilicate, and sodium silicate". Int. J. Toxicol. 24 (Suppl 1): 103–17. doi:10.1080/10915810590918643. PMID 15981734.