Silicates and silicones

The stoichiometric reaction of 516 g of dimethyldichlorosilane with water results in a tetrameric cyclic product X in 75% yield. The weight (in g) of X obtained is _____.

[Use, molar mass ($\mathrm{g\,mol^{-1}}$): H = 1, C = 12, O = 16, Si = 28, Cl = 35.5]

Match List - I with List - II.

Choose the correct answer from the options given below :

Match the items in Column I with its main use listed in Column II :

Column I	Column II
(A) Silica gel	(i) Transistor
(B) Silicon	(ii) Ion-exchanger
(C) Silicone	(iii) Drying agent
(D) Silicate	(iv) Sealant

Under hydrolytic conditions, the compounds used for preparation of linear polymer and for chain termination, respectively, are

Example of a three-dimensional silicate is :

The value of n in the molecular formula $\ce{Be_nAl2Si6O18}$ is

All the compounds listed in Column I react with water. Match the result of the respective reactions with the appropriate options listed in Column II.