Question

Silicones have the general formula:
A)$SiO_{4}^{4-}$
B)$S{{i}_{2}}O_{7}^{6-}$
C)${{\left( {{R}_{2}}SiO \right)}_{n}}$
D)$\left( Si{{O}_{3}} \right)_{n}^{2-}$

Answer 1

The answer to this question is based on the concept of physical chemistry that deals with the structures of the compounds which come under the polymerization topic and the silicones are the compounds in which organic groups are attached with silicon.

Complete answer:
We have studied about the various polymerization processes in the lower classes of chemistry and also their properties, preparation, structure, uses and also types of polymers.
Now, let us see what silicones are and how can it be manufactured so that we can deduce the required answer.
- Silicones are basically the synthetic polymers which have silicon – oxygen backbone which is similar to that of the silicon dioxide (silica) but the only difference is that this polymer is composed of organic groups that are attached with silicon atoms (C-Si) bonds.
- The organic groups attached to the silicones are exposed outside the chain of the polymer.
Now, if we see the options, in the option A), B) and D), there are only silicon and oxygen backbone and since the silicones have the organic group attached with it that are projected outwards the chain, these options can be ruled out. Also option A) and B) do not represent the polymer chain.
- Usually organic groups are denoted by ‘R’ and therefore in option C) there is presence of silicon and oxygen backbone along with that of the organic group ‘R’ attached to it.

Thus, the correct answer is option C) ${{\left( {{R}_{2}}SiO \right)}_{n}}$.

Note:
Important thing to be noted is that the silicones can withstand the extreme stress and temperature and because of this property, they are used as adhesives and sealants to seal the doors, windows, hydraulic switches etc.