Concept:Energy band gaps reflect electrical conductivity: conductors have overlapping bands (\( E_g = 0\text{ eV} \)), semiconductors have moderate gaps (\( \approx 1\text{ eV} \)), and insulators have wide gaps (\( > 3\text{ to } 6\text{ eV} \)).
Formula:$$E_{g,\text{Conductor}} (0\text{ eV}) < E_{g,\text{Semiconductor}} (\approx 0.7\text{–}1.1\text{ eV}) < E_{g,\text{Insulator}} (> 5\text{ eV})$$
Solution:- Conductor (e.g., Copper): \( E_g = 0\text{ eV} \) (overlapping bands).
- Semiconductor (e.g., Silicon): \( E_g \approx 1.1\text{ eV} \).
- Insulator (e.g., Diamond): \( E_g \approx 5.5\text{ eV} \).
- In order of increasing band gap: Conductor < Semiconductor < Insulator.
Why other options are incorrect:- Option A: Insulators have the largest band gaps, not the smallest.
- Option B: Conductors have smaller band gaps than semiconductors.
- Option C: Insulators have larger band gaps than semiconductors.
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