Which of the following is not a monomer for a high molecular mass silicone polymer?

Assertion : $SiF_6^{2-}$ is known but $SiCl_6^{2-}$ is not.
Reason : Size of fluorine is small and its lone pair of electrons interacts with $d-$orbitals of $Si$ strongly.

Identify the incorrect statement about silica $(SiO_2)$.

Silicon oil is obtained from the hydrolysis and polymerisation of

Hydrolysis of which of the following carbides does not take place?

Choose the correct statement about silicones.