What is energy gap in band theory ? Compare its size in conductors, semiconductors insulators

Explanation

### Step-by-Step Solution:

1. **Understanding Energy Gap in Band Theory**:
- In band theory, materials are described in terms of energy bands. The two primary bands are the **valence band** (where the electrons are present) and the **conduction band** (where electrons can move freely and conduct electricity).
- The **energy gap** (or **band gap**) is the energy difference between the top of the valence band and the bottom of the conduction band.

2. **Energy Gap in Conductors**:
- In conductors (like metals), the energy gap is **very small** or **negligible**. This means that electrons can easily move from the valence band to the conduction band, allowing for high electrical conductivity.
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