1. What are silicones? State the uses of silicones.

2.  What are boranes? Give chemical equation for the perparation of diborane.

(a) Silicones are a group of organosilicon polymers, which have (R2SiO) as a repeating unit. These may be linear silicones, cyclic silicones and cross-linked silicones.
These are prepared by the hydrolysis of alkyl or aryl derivatives of SiCL4 like RSiCl3, R2SiCl2, and R3SiCl and polymerisation of alkyl or aryl hydroxy derivatives obtained by hydrolysis.
2CH3Cl+Si570 KCu powder(CH3)2SiCl2+2H2O-2HClHydrolysis(CH3)2Si(OH)2