Answer: Metallic solid.
- A Ionic solid
- B Covalent solid
- C Molecular solid
- D Metallic solid
Correct answer: D. Metallic solid
Explanation: Metallic solids have delocalised electrons that move freely and carry electrical current.
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.