Diamond is not a good conductor of electricity because

Options

A. it is very hard
B. its structure is very compact
C. it is not water soluble
D. it has no free electron

Explanation

**Step-by-Step Solution:**

1. **Understanding Electrical Conductivity:**
- For a substance to conduct electricity, it must have free-moving charged particles. In solids, these charged particles are typically free electrons, while in liquids, they are free ions.

2. **Identifying the Structure of Diamond:**
- Diamond is an allotrope of carbon and is known for its crystalline structure. In diamond, each carbon atom is covalently bonded to four other carbon atoms, forming a three-dimensional (3D) network.

3. **Analyzing the Bonds in Diamond:**
- The bonds between the carbon atoms in diamond are covalent bonds. This means that the electrons are shared between the atoms, which leads to a strong and stable structure.

4. **Determining the Presence of Free Electrons:**
- Due to the nature of covalent bonding in diamond, there are no free electrons available. The electrons are localized in the covalent bonds and do not move freely throughout the structure.

5. **Conclusion:**
- Since diamond lacks free electrons in its solid state, it cannot conduct electricity. Therefore, diamond is not a good conductor of electricity.

**Final Answer:**
Diamond is not a good conductor of electricity because it has no free electrons.

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