What is the key feature of metallic bonding?

• A. Delocalised electrons surround positively charged metal ions
• B. Delocalised electrons surround negatively charged metal ions
• C. Localised electron pairs
• D. Hydrogen bonding network

Answer: (A)

Metallic bonding comes from a lattice of positive metal ions embedded in a sea of delocalised electrons that move freely around them. These electrons aren’t bound to any one ion, so they can flow and hold the ions together by electrostatic attraction. This description—delocalised electrons surrounding positively charged metal ions—best captures the essence of metallic bonding and explains why metals conduct electricity and are malleable. The other ideas don’t fit: there aren’t fixed negatively charged ions attracting electrons in a metal lattice, electron pairs aren’t localized as in covalent bonds, and hydrogen bonding doesn’t occur in metals.