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Pottery. Sodium silicate is used as a deflocculant in casting slips helping reduce viscosity and the need for large amounts of water to liquidize the clay body. It is also used to create a crackle effect in pottery, usually wheel-thrown. A vase or bottle is thrown on the wheel, fairly narrow and with thick walls.
Sodium metasilicate is the chemical substance with formula Na. 2SiO. 3, which is the main component of commercial sodium silicate solutions. It is an ionic compound consisting of sodium cations Na+. and the polymeric metasilicate anions [– SiO2−. 3 –] n. It is a colorless crystalline hygroscopic and deliquescent solid, soluble in water ...
Dealkalization is a process of surface modification applicable to glasses containing alkali ions, wherein a thin surface layer is created that has a lower concentration of alkali ions than is present in the underlying, bulk glass. This change in surface composition commonly alters the observed properties of the surface, most notably enhancing ...
Precipitated silica. Precipitated silica is an amorphous form of silica (silicon dioxide, SiO 2); it is a white, powdery material. Precipitated silica is produced by precipitation from a solution containing silicate salts. The three main classes of amorphous silica are pyrogenic silica, precipitated silica and silica gel.
Water glass ( sodium silicate [Na 2 SiO 3 or (Na 2 O)(SiO 2)] ) is a high strength binder used with silica molding sand both for cores and molds. [ 22 ] : 69–70 To cure a mixture of finely ground sand (e.g. by using a sand muller) and 3 to 4% of sodium silicate the binder, carbon dioxide (CO 2 ) gas is used.
Particles finer than 0.1 μm (10 −7 m) in water remain continuously in motion due to electrostatic charge (often negative) which causes them to repel each other. [citation needed] Once their electrostatic charge is neutralized by the use of a coagulant chemical, the finer particles start to collide and agglomerate (collect together) under the influence of Van der Waals forces.
The subunits of colloidal silica particles are typically in the range of 1 to 5 nm. Whether or not these subunits are joined depends on the conditions of polymerization. Initial acidification of a water-glass (sodium silicate) solution yields Si(OH) 4. If the pH is reduced below 7 or if salt is added, then the units tend to fuse together in chains.
Soda–lime glass, also called soda–lime–silica glass, is the most prevalent type of glass, used for windowpanes and glass containers (bottles and jars) for beverages, food, and some commodity items. Some glass bakeware is made of soda-lime glass, as opposed to the more common borosilicate glass. [1] Soda–lime glass accounts for about 90% ...