Define conductors, semi-conductors and insulators.

What is energy gap in Band theory? Compare its size in conductors, semiconductors and insulators. Or Define the 'Forbidden zone' of an insulator.

What is energy gap in band theory? Compare its size in Conductors, semi Conductors and insulators?

Which is the correct relation for forbidden energy gap in conductor, semi conductor and insulator

Explain formation of energy band in solids. Distinguish between conductors, extrinsic and intrinsic semi-conductors and insulators on the basis of band theory.

The forbidden energy band gap in semi conductor , conductor and insulator are E_(1),E(2)and E_(3) , respectively. The relation among them is