Ionic equations

• What do balanced ionic equations show?


  The reacting ions in a chemical reaction
• What can ionic equations be used for?


  these equations can be used to represent what happens in precipitation reactions
• What do half equations represent?


  what happens when atoms or ions gain or lose electrons
• What are the ‘rules’ of ionic equations?


  elections are shown as e-

  The number of atoms of each element must be the same on both sides

  The total charge on each side must be the same (usually 0)
• Example of a balanced half equation?


  Al3+ + 3e- → Al (because three negatively charged electrons are needed to balance the three positive charges on the aluminium ion).
• In a typical precipitation reaction, two soluble reactants form an insoluble product and a soluble product.
• When two ions remain separate in a precipitation reaction they can be ignored when writing the ionic equation