Basic unit of a diamond crystal has a.....................shape.

Answer

To answer the question about the basic unit of a diamond crystal and its shape, we can break it down into clear steps:

### Step-by-Step Solution:

1. **Identify the Composition of Diamond**:
- Diamonds are made of carbon atoms. They are considered the purest form of carbon.

2. **Understand the Arrangement of Atoms**:
- In a diamond, carbon atoms are arranged in a specific geometric pattern.

3. **Determine the Shape of the Basic Unit**:
- The basic unit of a diamond crystal is known to have a tetrahedral shape.

4. **Explain the Tetrahedral Structure**:
- In a tetrahedral structure, each carbon atom is bonded to four other carbon atoms, forming a three-dimensional shape that resembles a tetrahedron.

5. **Conclude the Answer**:
- Therefore, the basic unit of a diamond crystal has a tetrahedral shape.

### Final Answer:
The basic unit of a diamond crystal has a tetrahedral shape.

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