Question

The percentage of free space in a body-centred cubic unit cell is

• A. 32
• B. 34
• C. 28
• D. 20

Hint:

In a body-centred cubic unit cell, about 28% of the space is free, and the rest is occupied by atoms.

Answer 1

The Correct Option is C

Step 1: Understanding body-centred cubic (BCC) unit cell.
In a body-centred cubic (BCC) unit cell, atoms are located at the eight corners and at the center of the cell. The space not occupied by the atoms is free space.
Step 2: Calculation of free space.
- The volume of the BCC unit cell is determined by the length of its edge and the volume of the atoms inside it. - The percentage of free space is calculated by comparing the total volume of the unit cell to the volume occupied by the atoms. The percentage of free space in a BCC unit cell is approximately 28%.
Final Answer: \[ \boxed{28} \]