Ionic bonds form only between different elements

Steps:

• Elements consist of atoms of the same type, lacking the electronegativity difference needed for ion formation.
• Ionic bonding requires electron transfer between metals and non-metals to create oppositely charged ions.
• Pure elements cannot produce such ions internally, as they have identical atoms.
• Thus, ionic bonding is absent in elemental forms like metals or noble gases.

Why B is correct:

• Ionic bonding, by definition, occurs between atoms of different elements with high electronegativity differences, forming cations and anions (e.g., NaCl, not pure Na or Cl).

Why the others are wrong:

• A: Covalent bonds form between identical non-metal atoms, as in diamond (carbon) or O2.
• C: Metallic bonds occur in pure metal elements, like copper, via delocalized electrons.
• D: Van der Waals forces act between atoms or molecules in elemental gases, like noble gases.

Final answer: B