Which of the following statements is/are correct 1) Conductor contains a large number of electrons in the conduction band at room temperature. No energy gaps exist and the valence and conduction bands overlap. 2) A semiconductor is a material in which the energy gap is so large that practically no electron can be given enough energy to jump this gap. 3) An insulator is a solid with an energy gap small enough for electrons to cross rather easily from the valence band to conduction band.?

1 only
2 only
3 only
1, 2 and 3

LohaHridoy

4 views

2025-01-04 04:42

1 Answers

AhmedNazir

Option 1 : 1 only

Conductors, semiconductors and insulators can be distinguished with respect to their conduction band and valence band
For a material to conduct electricity the electrons from the valence band must shift to the conduction band
In the case of conductors like metals, the valence band and conduction band overlap each other and almost all the charge carriers are found in the conduction band; This is the reason they are good conductors of electricity
In the case of semiconductors, there is a gap between the valence band and the conduction band and only a small quantity of charge carriers are found in the conduction band; Hence, they are not very good conductors of electricity
In the case of insulators, the gap between the valence band and the conduction band is very large, and no charge carriers are found in the conduction band; Thus, they do not conduct electricity

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4 views Answered 2022-09-04 04:29

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