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Question
- Assertion (A): In insulators, the forbidden gap is very large.
- Reason (R): The valence electrons in an atom of an insulator are very tightly bound to the nucleus.
Options
Both Assertion (A) and Reason (R) are true and (R) is the correct explanation of (A).
Both Assertion (A) and Reason (R) are true and (R) is NOT the correct explanation of (A).
Assertion (A) is true and Reason (R) is false.
Assertion (A) is false and Reason (R) is also false.
Solution
Both Assertion (A) and Reason (R) are true and (R) is the correct explanation of (A).
Explanation:
An insulator is a substance with a high band gap or difference in energy between the valence and conduction bands. Because of the large energy difference, electrons find it difficult to travel to the conduction band, where they can flow and generate an electrical current, implying that the electrons are very firmly bound.
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