Which one of the following is an example of a covalent network solid?a. SiO2b. Kc. I2d. CaCl2e. None of these.

SiO2

Explanation:

A covalent network solid is a solid substance held together by a network of covalent bonds. Silicon dioxide forms a three dimensional covalent network solid structure.

Silicon dioxide is comprised of a network in which each silicon atom is at the centre of a tetrahedron of four oxygen atoms. Each of the oxygen atoms is also bonded to another silicon atom, at the centre of its own tetrahedron of oxygen atoms. This gives rise to a crystalline solid structure which is hard, having a high melting point.