Silicates as the base of the Earth crust
Silica and compounds derived from it, silicates, constituteca. `90%` of the Earth crust substances. Silica gives rise to a beautiful meterial-glass. Nobody knows exactly how glass was discovered. There is a well-favoured story related to phoenician sailors who fused occassionally sea sand and soda ash. It is likely that they discovered the secret of "liquid glass" `(LGL)` sodium metasilicate `(Na_(2)SiO_(3))` soluble in water.
The solution of LGL was used earlier as office glue. Write down the net ionic equation accounting for the ability of LGL to set in air. Hydrolysis of LGL in water allows abtaining a colloidal solution of silicic acid.

Answer

A