A metallic lattice is characterized by which description?

• A. 3D cations form a rigid lattice surrounded by a sea of electrons
• B. A lattice of ions arranged in a repeating array
• C. A 3D network of covalent bonds
• D. Individual molecules held together by hydrogen bonds

Answer: (A)

Metallic bonding involves positively charged metal ions arranged in a rigid three-dimensional lattice with a sea of delocalized electrons moving around them. The electrons are not tied to any one ion, so they flow freely and hold the cations together by electrostatic attraction. This combination gives metals their strength and rigidity while also allowing electrical conductivity and malleability because the electrons can move without breaking the lattice.

This description matches the idea of a 3D lattice of cations surrounded by a sea of electrons. Other descriptions don’t fit metals: a lattice of ions in a repeating array refers to ionic solids like salt, a 3D network of covalent bonds describes covalent-network solids such as diamond, and discrete molecules held together by hydrogen bonds describe molecular substances.