Question
Physics Question on band theory of solids
The energy gap between the valence band and the conduction band for a material is 6 eV. The material is
A
an insulator
B
a metal
C
an intrinsic semiconductor
D
a superconductor
Answer
an insulator
Explanation
Solution
Insulators have large energy gap between valence and conduction bands (about 6 eV), while semiconductors have a smaller one and conductors, the smallest energy gap.