Answer: 4.17 g/cm³.
- A 2.60 g/cm³
- B 4.17 g/cm³
- C 1.04 g/cm³
- D 5.21 g/cm³
Correct answer: B. 4.17 g/cm³
Explanation: d = (4 × 60) / (6 × 10²³ × (4 × 10⁻⁸)³) = 240 / (6 × 10²³ × 64 × 10⁻²⁴) = 240 / 38.4 ≈ 4.17 g/cm³.
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.