chem

Sea of Electrons Model

  • Metal atoms form cations for stable electron configurations, sharing valence electrons freely in metals.
  • Metallic bonds: electrostatic attraction between free-moving valence electrons and positive metal cations.
  • Metallic bonding modeled as a "sea of electrons."

Properties of Metals

Extended Structures

  • Metals have regular structures, not discrete molecules, held by the sea of electrons.
  • Specific properties derived from the sea of electrons are conductivity, malleability, and ductility.

Malleability and Ductility

  • Metals change shape without breaking; cations slide past each other while electrons move.
  • Metals can be drawn into wires due to flexible atomic structure that prevents breaking.

Melting and Boiling Points

  • Metals generally have high melting and boiling points due to strong electrostatic forces.
  • Examples: Iron - 1535°C, Sodium - 98°C, Magnesium - 649°C.
  • Higher nuclear charge & valence electrons increase melting point through stronger attraction.
  • Sodium ions (1+) vs. Magnesium ions (2+); more electrons from magnesium lead to stronger bonds.

Conductive Properties

  • Metals like copper, aluminum, and iron are used for cooking.
  • Delocalized electrons rapidly transfer kinetic energy, enhancing heat conductivity.
  • High melting points make them suitable for cookware.