What does the ratio ‘space occupied/total space’ denote?

Options

A. Packing factor
B. Packing efficiency
C. Particle fraction
D. Packing unit

Answer

To solve the question, we need to understand the terms involved and what the ratio of 'space occupied' to 'total space' signifies in the context of chemistry, particularly in crystallography.

### Step-by-Step Solution:

1. **Understanding the Terms**:
- **Space Occupied**: This refers to the volume occupied by the particles (atoms, ions, or molecules) within a unit cell of a crystal lattice.
- **Total Space**: This refers to the total volume of the unit cell itself.

2. **Defining the Ratio**:
- The ratio of 'space occupied' to 'total space' can be mathematically expressed as:
\[ \text{Packing Factor} = \frac{\text{Space Occupied}}{\text{Total Space}} \]

3. **Interpreting the Packing Factor**:
- The packing factor indicates how efficiently the particles are packed within the unit cell. A higher packing factor means that a greater proportion of the unit cell's volume is occupied by the constituent particles, while a lower packing factor indicates more empty space within the unit cell.

4. **Conclusion**:
- Therefore, the ratio 'space occupied/total space' denotes the **Packing Factor** of the unit cell.

### Final Answer:
The ratio 'space occupied/total space' denotes the **Packing Factor**.

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