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

Passive fire protection

Passive fire protection is an integral component of the three components of structural fire protection and fire safety in a building. PFP attempts to contain fires or slow the spread, through use of fire-resistant walls, floors, and doors...

, refractories, textile and lumber processing, and automobiles. Sodium carbonate

Sodium carbonate

Sodium carbonate , Na2CO3 is a sodium salt of carbonic acid. It most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. Sodium carbonate is domestically well-known for its everyday use as a water softener. It can be extracted from the...

 and silicon dioxide

Silicon dioxide

The chemical compound silicon dioxide, also known as silica , is an oxide of silicon with the chemical formula '. It has been known for its hardness since antiquity...

 react when molten to form sodium silicate and carbon dioxide

Carbon dioxide

Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...

:

Na₂CO₃ + SiO₂ → Na₂SiO₃ + CO₂

Anhydrous sodium silicate contains a chain polymeric anion composed of corner shared {SiO₄} tetrahedral, and not a discrete SiO₃²⁻ ion.