Which description matches a metallic lattice?

Which description matches a metallic lattice?

• A. Particles: Molecules; Forces: Van der Waals; Properties: Low melting point; not conductors.
• B. Particles: Ions; Forces: Electrostatic; Properties: High melting point, not conductors.
• C. Particles: Positive ions and delocalized electrons; Forces: Metallic bonding; Properties: High melting point, good conductors.
• D. Particles: Atoms; Forces: Covalent bonds; Properties: Hard.

Answer: (C)

Metallic bonding features a lattice of positively charged ions surrounded by a sea of delocalized electrons. This arrangement explains both why metals have high melting points and why they conduct electricity: the strong attraction between the fixed ions and the freely moving electrons holds the lattice together, while the mobile electrons carry charge through the structure. The description that lists particles as positive ions and delocalized electrons, forces as metallic bonding, and properties of high melting point and good conductors matches exactly what a metallic lattice is. Other descriptions don’t fit as well. A model based on molecules held together by van der Waals forces describes weak, easily melts and non-conductive substances, not a metallic lattice. An ionic lattice emphasizes electrostatic attraction between ions and typically shows a very high melting point but poor conductivity as a solid, since ions are not free to move. A covalent network description involves atoms bonded by directional covalent bonds, leading to very hard materials, but not the delocalized electrons that give metals their characteristic electrical conductivity.

Metallic bonding features a lattice of positively charged ions surrounded by a sea of delocalized electrons. This arrangement explains both why metals have high melting points and why they conduct electricity: the strong attraction between the fixed ions and the freely moving electrons holds the lattice together, while the mobile electrons carry charge through the structure. The description that lists particles as positive ions and delocalized electrons, forces as metallic bonding, and properties of high melting point and good conductors matches exactly what a metallic lattice is.

Other descriptions don’t fit as well. A model based on molecules held together by van der Waals forces describes weak, easily melts and non-conductive substances, not a metallic lattice. An ionic lattice emphasizes electrostatic attraction between ions and typically shows a very high melting point but poor conductivity as a solid, since ions are not free to move. A covalent network description involves atoms bonded by directional covalent bonds, leading to very hard materials, but not the delocalized electrons that give metals their characteristic electrical conductivity.