C3 - Bonding

• Ions

  Charged particles formed when atoms lose or gain electrons
• What is Ionic Bonding

  electrostatic attraction between positive and negative ions

  • Between Metals and Non Metals
• How are Ionic Compounds held together?

  They are held together in a giant lattice

  • Electrostatic attractions between positive and negative ions hold the structure together
• Properties of Ionic Substances

  • High melting and boiling point - as the strong forces require a lot of energy to break them
  • Do not conduct electricity when solid - ions are in fixed positions
  • Conductors when molten or dissolved in water- ions are free to move.
• What is a Covalent Bond

  shared lair of electrons between atoms

  • Takes place between non-metals
• Simple molecular covalent substances

  • Don't conduct electricity
  • Small molecules
  • Weak intermolefular forces
  • Low melting and boiling points
• Giant Covalent Structures

  • Solid, atoms covalently bonded together in giant lattice
  • High melting/boiling points - strong covalent bonds
  • Mostly doesn't conduct electricity
  • E.G Diamond, graphite, silicon dioxide
• Metallic Bonding

  Forces of attraction between delocalised electrons and nuclei of metal ions
• Alloys

  • mixtures of metals with other elements
  • different sizes of atoms distorts the layers, so they can't slide over eachother