Which characteristic of electrons in metal elements is primarily responsible for metallic bonding?

• A. Electrons are shared between two specific atoms forming directional bonds.
• B. Electrons are transferred completely from one atom to another.
• C. Electrons are tightly bound to individual atoms and do not move.
• D. Electrons are delocalized and move freely throughout the metal lattice.

Answer: (D)

Verified step by step guidance

1. Understand that metallic bonding involves the interaction between metal atoms and their electrons.
2. Recall that in metallic bonding, electrons are not localized between two specific atoms, unlike covalent bonds which are directional.
3. Recognize that electrons are not completely transferred from one atom to another, which would describe ionic bonding.
4. Note that electrons in metals are not tightly bound to individual atoms; instead, they are free to move throughout the entire metal structure.
5. Conclude that the key characteristic responsible for metallic bonding is that electrons are delocalized and move freely throughout the metal lattice, creating a 'sea of electrons' that holds the metal atoms together.