The energy gap (in eV) between the valence and conduction bands of an insulator is of the order of ?
Answer: 5
Explanation
The energy gap (also called band gap) is the energy difference between the valence band (where electrons are bound) and the conduction band (where electrons are free to move).
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In conductors, the band gap is zero or overlaps.
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In semiconductors, the band gap is around 1 eV (e.g., silicon ≈ 1.1 eV).
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In insulators: The band gap is large, typically greater than 3 eV, and often around 5 eV or more.
This large gap in insulators prevents electrons from moving to the conduction band, making them poor conductors of electricity
