sodium silicate(redirected from E550)
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sodium silicate,any one of several compounds containing sodium oxide, Na2O, and silicasilica
or silicon dioxide,
chemical compound, SiO2. It is insoluble in water, slightly soluble in alkalies, and soluble in dilute hydrofluoric acid. Pure silica is colorless to white.
..... Click the link for more information. , Si2O, or a mixture of sodium silicates. Sodium orthosilicate is Na4SiO4 (or 2Na2O·SiO2); sodium metasilicate is Na2SiO3 (or Na2O·SiO2); sodium disilicate is Na2Si2O5 (or Na2O·2SiO2); sodium tetrasilicate is Na2Si4O9 (or Na2O·4SiO2). All these compounds are transparent, glassy or crystalline solids that have high melting points (above 800°C;) and are water soluble. They are produced chiefly by fusing sand and sodium carbonate in various proportions. The product is commonly known as water glasswater glass
or soluble glass,
colorless, transparent, glasslike substance available commercially as a powder or as a transparent, viscous solution in water. Chemically it is sodium silicate, potassium silicate, or a mixture of these.
..... Click the link for more information. . The greatest single use of sodium silicates is as a raw material for making silica gelsilica gel,
chemical compound. It is a colloidal form of silica, and usually resembles coarse white sand. It may be prepared by partial dehydration of metasilicic acid, H2SiO3. Because it has many tiny pores, it has great adsorptive power.
..... Click the link for more information. .
any of the sodium salts of silicic acids. Known anhydrous sodium silicates include sodium metasilicate (Na2O·SiO2 or Na2SiO3), sodium orthosilicate (2Na2O·SiO2 or Na4SiO4), sodium sesquisilicate (3Na2O·2SiO2 or Na6Si2O7), sodium bisilicate (Na2O·2SiO2 or Na2Si2O5), and sodium trisilicate(Na2O·3SiO2 or Na2Si3O7).