Metals (OCR Gateway GCSE Chemistry: Combined Science)

Metallic Bonding

• Metals are examples of giant structures
• Within the giant metal structure, the atoms lose their outer shell (valence) electrons and become positively charged metal ions
  
  • The outer shell electrons no longer belong to any specific metal atom and are said to be delocalised
  • This means they can move freely between the positive metal ions and act like a sea of "delocalised electrons”
  • It is these delocalised electrons that allow metals to conduct electricity
• The structure is made up of metal ions arranged in a regular pattern, with strong electrostatic attractions between the positive metal ions and the negative sea of delocalised electrons
• The individual metal atoms are held together by these strong metallic bonds forming a lattice structure,
  • This exists in all metals and metal alloys, which are mixtures of metals

Diagram showing metallic lattice structure with delocalised electrons