Question

Three types of bands are shown in the figures given below showing the position of the valence band and conduction band. The figures $A$, $B$ and $C$ represent

	$A$	$B$	$C$
(a)$\,\,$	Non-metal$\,\,$	Metal$\,$	Semiconductor$\,\,$
(b)$\,\,$	Semiconductor$\,\,$	Insulator$\,\,$	Conductor$\,\,$
(c)$\,\,$	Metal$\,\,$	Insulator$\,\,$	Semiconductor$\,\,$
(d)$\,\,$	Insulator	Conductor$\,\,$	Semiconductor

• A. a
• B. b
• C. c
• D. d

Answer 1

Answer: (C)

Conductors, semi-conductors and insulators can be defined on the basis of conduction band and valence band.
In conductors, the conduction band and valence band overlap each other.
In semi-conductor, the energy gap between the conduction band and valence band $∼1\,eV$.
In insulators, the energy gap between the conduction band and valence band $> 9\,eV$.