Answer: 8.
- A 8
- B 4
- C 6
- D 12
Correct answer: A. 8
Explanation: An FCC unit cell effectively contains 4 atoms, and the number of tetrahedral voids is twice the number of atoms, giving 2 x 4 = 8.
The three cubic unit cells: Simple Cubic has atoms only at corners; Body-Centred adds one atom at the centre; Face-Centred adds one atom at the centre of each of the 6 faces, giving the highest packing efficiency.
Concept context
Explore the ordered world of crystalline solids: unit cells, packing, defects, and how structure determines electrical and magnetic properties.