Redox reactions

• Oxidation (in terms of electrons)

  Loss of electrons
• Reduction (in terms of electrons)

  Gaining of electrons
• Redox reaction

  A reaction in which both oxidation and reduction take place
• Metal displacement reaction

  Where a more reactive metal displaces a less reactive metal in a compound
• Half equation

  An equation that shows the gain or loss of electrons of a single element in a reaction
• Half equation for the oxidation of magnesium

  Mg -> Mg2+ + 2e-
• In displacement reactions are the metal ions reduced or oxidised

  Ions are reduced
• In displacement reactions are metal atoms reduced or oxidised

  Oxidised
• What is shown in ionic equations

  Only the particles that react and the products they form are shown - the ions that don’t change are ignored
• Ions that aren’t involved in a reaction

  Spectator ions
• Ionic equation for: Mg + ZnCl2 + MgCl2 + Zn

  Mg + Zn2+ —> Mg2+ + Zn