Question

Choose the correct option to complete the following statement.
In an insulator, the band gap is so ............... that the electrons in the valence band are not easily ............... into the conduction band.

• A. large, promoted
• B. small, promoted
• C. large, dropped
• D. small, dropped

Answer 1

The correct option is A large, promoted

In insulators, the electrons in the valence band are separated by a large gap from the conduction band while in conductors like metals, the valence band overlaps the conduction band and in semiconductors, there is a small enough gap between the valence and conduction bands such that thermal or other excitations can bridge the gap.