Answer: zero or overlapping.
- A large, about 6 eV
- B zero or overlapping
- C about 1 eV
- D about 3 eV
Correct answer: B. zero or overlapping
Explanation: In conductors the valence and conduction bands overlap (effectively zero gap), so electrons move freely and conduct readily.
Conductors have overlapping bands, semiconductors have a small energy gap that can be bridged by heat or doping, and insulators have a large gap that blocks conduction.
Concept context
Band theory, p-n junction, diodes, transistors, logic gates, and integrated circuits.