Module 2- Types of Bonding

• Ionic


  The electrostatic attraction between positive and negative ions
• Ionic compounds are solid at room temperature with high melting and boiling points because a large amount of energy is needed to break the strong electrostatic forces of attraction holding the opposite ions together.
• Ionic compounds cannot conduct electricity when solid because the ions are in a fixed position.
• Ionic compounds when dissolved in water or molten are good conductors as ions are free to move so electricity can flow.
• Ionic compounds are soluble in polar solvents.
• Covalent Bonding


  Strong electrostatic attraction between a shared pair of electrons and the nuclei of bonded atoms.
• Giant Covalent Lattices


  Many atoms bonded together by covalent bonds. (Diamond/Graphite/Graphene)
• Diamond

  • 4 carbons
  • tetrahedral shape
  • strong covalent bonds
  • high melting point
  • poor conductor
  • insoluble in water
• Graphite

  • 3 carbons
  • trigonal planar shape
  • layered with delocalised electrons between
  • high melting point
  • strong covalent bonds
  • good conductor
  • insoluble in water
  • weak forces holding layers
• Graphene

  • 3 carbons
  • sheet of carbons in hexagons
  • one atom thick
  • best conductor of electricity
  • high melting and boiling point
  • transparent and incredibly light