Which among the following metals crystallises as a simple cube ?

Options

A. Polonium
B. Iron
C. Copper
D. Gold

Answer

To determine which metal crystallizes as a simple cube, we need to understand the different types of cubic crystal structures and identify the correct option based on that understanding.

### Step-by-Step Solution:

1. **Understanding Crystal Structures**:
- There are three main types of cubic crystal structures: Simple Cubic (SC), Face-Centered Cubic (FCC), and Body-Centered Cubic (BCC).
- In a Simple Cubic structure, atoms are located only at the eight corners of the cube.

2. **Identifying the Simple Cubic Structure**:
- In a Simple Cubic structure, the coordination number is 6, and there is only one atom per unit cell.
- The atoms at the corners contribute to the unit cell, but there are no additional atoms at the face centers or body center.

3. **Analyzing the Options**:
- We need to evaluate the metals provided in the options to see which one crystallizes in a Simple Cubic structure.
- The question mentions options like Polonium, Iron, Copper, and Gold.

4. **Evaluating Each Metal**:
- **Polonium**: It is known to crystallize in a Simple Cubic structure.
- **Iron**: Iron crystallizes in a Body-Centered Cubic (BCC) structure.
- **Copper**: Copper crystallizes in a Face-Centered Cubic (FCC) structure.
- **Gold**: Gold also crystallizes in a Face-Centered Cubic (FCC) structure.

5. **Conclusion**:
- Based on the analysis, the only metal that crystallizes as a Simple Cubic is **Polonium**.

### Final Answer:
The metal that crystallizes as a simple cube is **Polonium**.

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