Question

what is silicones? how are they formed? write aa the reactions.

Answer 1

Answer:

Silicones are prepared by the hydrolysis of alkyl or aryl substituted silicon halides. Alkyl or aryl substituted silicon halides are prepared by passing gaseous alkyl or aryl halide over an alloy of copper and silicon at 300°C. The hydrolysis of dimethyldichlorosilane gives dimethyl silanol.

Answer 2

Sillicones are polymers that are made by atoms of alternate molecules of sillicon and oxygen , frequently combined by carbon and hydrogen.

Sillicones are generally prepared by hydrolysis of dialkyldichlorosillanes(R2SiCl2) or diarychlorosillanes( Ar2SiCl2) which is prepared by passing vapors of RCl or ArCl over Si in the presence of catalyst copper.

Reaction:

2RCl + Si ---------> R2SiCl2

Copper(540 K)

R2SiCl2 -----------> O-Si-O-Si-O-Si-O-HCl

Sillicones can be in form of oil or rubber depending on extent of polymerisation.

☘️☘️☘️____☘️☘️☘️