Metallic Bonds Notes

Metallic Bonds

Overview

• Metallic Bond Definition: A chemical attraction formed from a shared pool of valence electrons.
• An interaction that holds metal atoms together.
• Does not result in the formation of a compound.
• Metal atoms do not lose their valence electrons as they do in ionic bonds.
• All metal atoms share electrons from a "sea of electrons."
• Delocalized Electrons: Electrons that are not associated with a single atom or bond.

Comparison to Ionic and Covalent Bonds

• Ionic Bond: Involves the transfer of electrons (e.g., Sodium chloride NaCl).
• Metallic Bond: Involves the sharing of a pool of valence electrons among metal atoms (e.g., Zinc Zn).
• Covalent Bond: Depicted with water (H_2O), illustrating shared electrons between nonmetal atoms.

Properties Contributing to Metallic Bonding

• Electronegativity (EN): Metals have low electronegativity, resulting in a lower attraction for electrons.
• Lattice Formation: Metals tend to form lattices, similar to ionic compounds.
• Atomic Size and Overlapping Orbitals: Metal atoms are often larger, leading to overlapping orbitals, which contributes to the formation of the "sea of electrons."

Properties of Metals

• Malleability: The ability to be made into thin sheets.
• Ductility: The ability to be made into wires.
• Electrical and Thermal Conductivity: The sea of electrons allows electrons to flow through the material, producing an electric current.
• Light Absorption and Reflection: Metals are strong absorbers and reflectors of light, giving them a metallic appearance.

Alloys

• Definition: Typically a solution of two or more metals mixed together.
• The proportion of metals can be adjusted to create desirable properties.
• Alloys are widely used due to their desirable and tunable properties.