What is energy gap in bond theory?

Explanation

### Step-by-Step Solution:

1. **Understanding Band Theory**:
- Band theory explains the behavior of electrons in solids. It describes how energy levels of electrons are grouped into bands, primarily the valence band and the conduction band.

2. **Defining Energy Gap**:
- The energy gap, also known as the band gap, is the energy difference between the top of the valence band and the bottom of the conduction band. It is a crucial concept in determining the electrical conductivity of materials.

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