Question

Solid A is a very hard electrical insulator in solid as well as in molten state and melts at an extremely high temp. What type of solid is it?

Answer 1

Covalent network solids

1. Solids whose molecules are covalently bonded as a network in their lattice structure are called covalent network solids.
2. The molecules are bonded to each other covalently and thus can be said to be one giant molecule.
3. They are very hard.
4. They are also good insulators because they do not have free electrons.
5. They melt at very high temperatures because breaking strong covalent bonds between the molecules requires a high input of energy.
6. Examples include diamond, quartz, silicon carbide, etc.

Therefore, the solid described is a covalent network solid.