Answer: 26%.
- A 26%
- B 32%
- C 48%
- D 52%
Correct answer: A. 26%
Explanation: FCC has a packing efficiency of 74%, so the fraction of empty space is 100 - 74 = 26%.
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.