Although pure silicon is an insulator, then how does it behave as semi-conductor on heating ?

Explanation

### Step-by-Step Solution:

1. **Understanding Pure Silicon**:
- Pure silicon (Si) is a group IV element with a crystalline structure. In its pure form, silicon has a full valence shell with four electrons, forming covalent bonds with neighboring silicon atoms. This structure makes it an insulator at room temperature because there are no free charge carriers (electrons) available for conduction.

2. **Effect of Temperature**:
- When silicon is heated, the thermal energy provided to the silicon lattice increases. This energy can be sufficient to break some of the covalent bonds between silicon atoms.

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