Question

Silicone's are :

• A. synthetic polymers containing repeated $R_{2}SiO$ units.
• B. silicates with common $Si{O}_4$ unit.
• C. ketones with silyl group $\left(Si{H}_3\right)$ similar to alkyl $(Si{H}_3{)}_{2}CO$
• D. Zircon (neso silicates)

Answer 1

The correct option is A synthetic polymers containing repeated $R_{2}SiO$ units.

These are organosilicon polymers containing $R_{2}SiO$ repeating units and empirical formula analogous to ketone $\left(R_{2}CO\right)$

$-\underset{|}{\stackrel{|}{S}}i-O-\underset{|}{\stackrel{|}{S}}i-linkage$

Organic polymers containing silicon in them are called as silicones.
These are formed by hydrolysis of alkyl chlorosilanes and their polymerisation. The alkyl or aryl substituted chlorosilanes are prepared by the reaction of Grignard reagent and silicon tetrachlorides.