Sodium silicate

Hygroscopic chemical compound of variable Na2O/SiO2 ratio precursor of waterglass

Sodium silicate is a generic name for chemical compounds with the formula Na2xSiyO2y+x or (Na2O)x·(SiO2)y, such as sodium metasilicate (Na2SiO3), sodium orthosilicate (Na4SiO4), and sodium pyrosilicate (Na6Si2O7). The anions are often polymeric. These compounds are generally colorless transparent solids or white powders, and soluble in water in various amounts.

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