Which of the following properties is NOT explained by metallic bonding?

• A. Malleability and ductility of metals
• B. High electrical conductivity of metals
• C. Luster of metallic surfaces
• D. Formation of discrete molecules

Answer: (D)

Verified step by step guidance

1. Understand what metallic bonding is: Metallic bonding involves a lattice of metal cations surrounded by a 'sea' of delocalized valence electrons that are free to move throughout the structure.
2. Identify properties explained by metallic bonding: Because of the delocalized electrons, metals exhibit high electrical conductivity, malleability and ductility (due to the ability of metal ions to slide past each other without breaking bonds), and luster (as free electrons can absorb and re-emit light).
3. Analyze the property 'Formation of discrete molecules': Metallic bonding does not involve the formation of discrete molecules; instead, metals form extended lattice structures without distinct molecular units.
4. Conclude that the property NOT explained by metallic bonding is the formation of discrete molecules, as this is characteristic of covalent or molecular compounds, not metallic solids.
5. Therefore, the correct answer is the property that metallic bonding does NOT explain: 'Formation of discrete molecules.'