Question

Which of the following is/are the incorrect statement about silicones?

• A. They are made up of $S{i}_4^{4-}$ units
• B. They are polymers made up of $R_{2}SiO$ units
• C. They are water soluble compounds.
• D. They are hydrophilic in nature

Answer 1

Answer: (A), (C), (D)

The correct options are
A They are made up of $S{i}_4^{4-}$ units
C They are water soluble compounds.
D They are hydrophilic in nature

Synthetic organosilicon compounds having repeated $R_{2}SiO$ units held by $Si–O–Si$ linkages. These compounds have the general formula $(R_{2}SiO{)}_n$ where R = alkyl or aryl group.
Silicones being surrounded by non-polar alkyl groups are water repelling in nature thus hydrobhobic in nature. Hence correct option is a, c, d.

THEORY
Properties:

• Silicones being surrounded by non-polar alkyl groups are water-repelling in nature.
• They have in general high thermal stability.
• Good electrical insulation (High dielectric strength)
• Chemical Inertness (resistance to oxidation and a high number of chemicals.)

Uses of Silicones:

• They are used as sealants, greases, electrical insulators, and for waterproofing of fabrics.
• Being biocompatible they are also used in surgical and cosmetic plants.
• Products with the same physical properties of oils, rubbers, and resins can be produced using silicones.