The co`-`ordination number of a body `-` centred atom is `:`

Options

A. 8
B. 12
C. 6
D. 4

Explanation

To determine the coordination number of a body-centered atom in a body-centered cubic (BCC) lattice, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of BCC**:
- In a body-centered cubic lattice, there are atoms located at each of the eight corners of the cube and one atom at the center of the cube.

2. **Identify the Central Atom**:
- The atom located at the center of the cube is referred to as the body-centered atom.

3. **Determine Neighboring Atoms**:
- The coordination number is defined as the number of nearest neighboring atoms surrounding a central atom. In the case of the body-centered atom, we need to identify how many corner atoms are nearest to it.

4. **Count the Neighbors**:
- The body-centered atom is surrounded by the eight corner atoms of the cube. Each of these corner atoms is a nearest neighbor to the body-centered atom.

5. **Conclusion**:
- Therefore, the coordination number of the body-centered atom in a BCC lattice is 8.

### Final Answer:
The coordination number of a body-centered atom is **8**.

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