Answer: 2.0 eV.
- A 1.1 eV
- B 1.4 eV
- C 3.0 eV
- D 2.0 eV
Correct answer: D. 2.0 eV
Explanation: E<sub>g</sub> = hc/λ = 1240/620 = 2.0 eV, the energy of the emitted photon.
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.