Q. In silica $(SiO_{2})$, each silicon atom is bonded to
A) Two oxygen atoms
B) Four oxygen atoms
C) One silicon and two oxygen atoms
D) One silicon and four oxygen atoms
Explanation
(b)
In silica, silicon has large size, so the 3$p$-orbitals of Si does not overlap effectively with $2p -$orbitals of oxygen. Therefore, Si=O are not formed. The tetravalency of Si is satisfied by the formation of $Si - O$ bonds, thus it is surrounded by four oxygen atoms.
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.