سیلیکات سدیم | پترو کویر صدر | Petro Kavir Sadr

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Sodium silicate is the common name for a compound sodium metasilicate, Na₂SiO₃, also known as water glass or liquid glass. It is available in aqueous solution and in solid form and is used in cements, passive fire protection, refractories, textile and lumber processing, and automobiles. Sodium carbonate and silicon dioxide react when molten to form sodium silicate and carbon dioxide^[1]:

Na₂CO₃ + SiO₂ → Na₂SiO₃ + CO₂

Anhydrous sodium silicate contains a chain polymeric anion composed of corner shared {SiO₄} tetrahedra, and not a discrete SiO₃²⁻ ion^[1]. In addition to the anhydrous form there are a number of hydrates with the formulae Na₂SiO₃.nH₂O (where n= 5, 6, 8, 9) which contain the discrete approximately tetrahedral anion SiO₂(OH)₂²⁻ with water of hydration e.g. the commercially available sodium silicate pentahydrate, Na₂SiO₃.5H₂O is formulated Na₂SiO₂(OH)₂.4H₂O and the nonahydrate, Na₂SiO₃.9H₂O is formulated Na₂SiO₂(OH)₂.8H₂O