Metallic bonding and alloys

• Metallic bonding - electrostatic attraction between positive ions and delocalised electrons
• Alloy - a mixture of two or more elements where at least one is a metal
• • Metals consist of giant structures of atoms arranged in a regular pattern.
  • The electrons from the outer shell of metal atoms are delocalised and are free to move though the whole structure.
  • Therefore making metals conductive of electricity.
• Metallic bonding - the sharing of delocalised electrons and moving between metal ions.
• Properties of metals:

  • Electrical conductors - delocalised electrons can carry electrical charge
  • Thermal conductors - energy transfer by delocalised electrons
  • High m.p. and b.p. - due to the giant structure and metallic bonds being strong
  • Soft and malleable - layers in metals slide over each other
• Alloy - mixture of two or more elements where at least one is a metal
• Why are alloys harder?

  • As alloys contain different elements, they have different sizes
  • These atoms distort the layers
  • So, when force is added the atoms can't slide over each other easily
  • Therefore, more force is needed to break alloys