Sodium chloride has a crystalline structure made up of `Na^(+) and Cl^(-)` ions. Why does NaCl not conduct electricity in solid state ?

Options

A. Solid do not conduct electricity
B. The ions of NaCl become mobile only in molten state and are not free to move in solid state
C. The crystalline structure does not have ions
D. When a bond is formed between ions they lose their charge

Answer

To understand why sodium chloride (NaCl) does not conduct electricity in its solid state, we can break down the explanation into several key points:

### Step-by-Step Solution:

1. **Crystalline Structure of NaCl**:
- Sodium chloride forms a crystalline structure where Na⁺ and Cl⁻ ions are arranged in a three-dimensional lattice. This arrangement is highly ordered and stable.

2. **Ionic Bonds**:
- The Na⁺ and Cl⁻ ions are held together by strong electrostatic forces of attraction, known as ionic bonds. These bonds create a rigid structure that does not allow for movement of the ions.

3. **Lack of Free Movement**:
- In the solid state, the ions in NaCl are fixed in place within the lattice structure. Because they cannot move freely, there are no charge carriers available to conduct electricity.

4. **Comparison with Liquid State**:
- When NaCl is melted or dissolved in water, the rigid lattice breaks down. The ions become mobile, allowing them to move freely. This mobility enables the conduction of electricity, as the ions can carry charge through the solution or molten state.

5. **Conclusion**:
- Therefore, the reason NaCl does not conduct electricity in the solid state is that the ions are not free to move due to the strong ionic bonds that hold them in place within the crystalline lattice.

### Final Answer:
NaCl does not conduct electricity in the solid state because its ions (Na⁺ and Cl⁻) are fixed in a rigid lattice structure and are not free to move.

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