Draw a labelled energy band diagram for a solid which is an insulator. What is the main difference between this diagram and that of a semiconductor?

Explanation

### Step-by-Step Solution:

1. **Understanding Energy Bands**: In solids, electrons occupy energy levels that are grouped into bands. The two most important bands are the valence band (filled with electrons) and the conduction band (where electrons can move freely and conduct electricity).

2. **Drawing the Energy Band Diagram**:
- **Valence Band**: Draw a horizontal line to represent the valence band. Label it "Valence Band".
- **Energy Gap**: Leave a significant space above the valence band to represent the energy gap. This gap is wide in insulators.
- **Conduction Band**: Draw another horizontal line above the energy gap to represent the conduction band. Label it "Conduction Band".
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