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1zeolite 2silica 3 silicone

1) Zeolites are microporous aluminosilicates .This framework has a negative charge which is neutralised by exchangeable cations.

Zeolites are used a molecular sieves and can separate molecules of different sizes. They are also used as catalyst.

 

2) Silica

Silica is widely distributed in nature as sand. Quartz, cristobalite, and tridymite are the crystalline forms of silica.

Each silicon atom is covalently bonded to four oxygen atoms in tetrahedral manner. 

The Si − O bond has very high enthalpy. Hence, silica in normal form is almost non-reactive. It resists the attack by halogens, most acids, and metals even at elevated temperature.

 

 

These are thegroup of organosilicon polymers with repeating units is .

Alkyl or aryl substituted silicon chlorides, R_nSiCl_{(4 − n),} are the starting materials for the manufacture of silicones. [R is alkyl or aryl group

Silicones are water repelling in nature. They have high thermal stability and dielectric strength and are resistant to oxidation and chemicals