ميتاسيليكات الپوتاسيوم

ميتاسيليكات الپوتاسيوم
K2SiO3idealized.png
Sodium-metasilicate-chain-from-xtal-3D-balls.png
الأسماء
اسم أيوپاك المفضل
Potassium metasilicate
أسماء أخرى
Liquid glass
Waterglass
المُعرِّفات
رقم CAS
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.029.989 Edit this at Wikidata
رقم EC
  • 233-001-1
E number E560 (acidity regulators, ...)
UNII
الخصائص
الصيغة الجزيئية K2O3Si
كتلة مولية 154.26 g mol-1
المظهر White crystals
المخاطر
ن.م.ع. مخطط تصويري الرمز التصويري في Globally Harmonized System of Classification and Labelling of Chemicals (GHS)The exclamation-mark pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)
ن.م.ع. كلمة الاشارة Danger
H314, H335
P260, P261, P264, P271, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P321, P363, P403+P233, P405, P501
NFPA 704 (معيـَّن النار)
Flammability code 0: لن يشتعل. مثل الماءHealth code 1: التعرض سيتسبب في تهيجاً ولكن لا يترك سوى جروح طفيفة باقية. مثل زيت الترپنتينReactivity code 0: مستقر في العادة، حتى تحت ظروف التعرض للنار، ولا يتفاعل مع الماء. مثل النيتروجين السائلSpecial hazards (white): no codeNFPA 704 four-colored diamond
0
1
0
مركبات ذا علاقة
Potassium carbonate
Potassium germanate
Potassium stannate
Potassium plumbate
Sodium silicate
ما لم يُذكر غير ذلك، البيانات المعطاة للمواد في حالاتهم العيارية (عند 25 °س [77 °ف]، 100 kPa).
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مراجع الجدول

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 amounts of water. These are white solids or colorless solutions.[1]

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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 silica. 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).[3] The thicker cell walls of the plant also provides an added mechanical resistance to sap sucking insects (e.g. spider mite) and various pathogenic fungi (e.g. powdery mildew).

Industrial uses

Some metal cleaning formulations use potassium silicate, which also serves as a corrosion inhibitor.[4] It also finds various uses in the fabrication of welding rods or even of cosmetics.

Silicon Dioxide production

Potassium silicate may also be employed in the glass recycling as an intermediate step in obtaining relatively pure and cheap SiO2 for further processing (e.g. for fused glass).[5]

Safety

Potassium silicate is strongly alkaline.[6]

See also

References

  1. ^ 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
  2. ^ Cobleigh, Rolfe (1909). Handy farm devices and how to make them. Part II: Worth knowing to render wood fireproof. New York: Orange Judd.
  3. ^ S. Y. Wang & G. J. Galletta (1998) Foliar application of potassium silicate induces metabolic changes in strawberry plants, Journal of Plant Nutrition, 21:1, 157-167, DOI:10.1080/01904169809365390
  4. ^ 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. S2CID 208153862.
  5. ^ Mori, H. (2003-08-01). "Extraction of silicon dioxide from waste colored glasses by alkali fusion using potassium hydroxide". Journal of Materials Science (in الإنجليزية). 38 (16): 3461–3468. doi:10.1023/A:1025100901693. ISSN 1573-4803.
  6. ^ Mori, H. (2003-08-01). "Extraction of silicon dioxide from waste colored glasses by alkali fusion using potassium hydroxide". Journal of Materials Science (in الإنجليزية). 38 (16): 3461–3468. doi:10.1023/A:1025100901693. ISSN 1573-4803.

External links