Silicate melt three-dimensional network

As discussed earlier, the addition of basic oxides to a melt (a basic oxide is an oxide which when dissolved in a melt contributes an oxygen ion to the melt, such as Na20 and CaO) will break up the silicate network by the formation of nonbridging oxygens. Increasing additions of the base oxides thus result in breakdown of the original three-dimensional network into progressively smaller discrete ions. As a result, the number of Si-O bonds needed to... 

Water glass is produced by co-melting of stoichiometric amounts of sodium cai bonate and silica. The newly formed alkali silicates are water-soluble under pressure and exhibit strong basic reaction. In contact with atmospheric CO2 and decreasing pH polymerization is enhanced. Eventually a three-dimensional network of a so-called soft-gel is formed, which agglutinates the soil or waste particles. Stability of the soft gel structure is preserved at pH less than 7. Full dryness affects formation of solid silica. 

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