Metals and Reactivity

• Displacement reaction is when a more reactive metal takes the place of a less reactive metal in a compound.
• Reactivity Series:

  • Potassium
  • Sodium
  • Calcium
  • Magnesium
  • Aluminium
  • Zinc
  • Iron
  • Copper
  • Silver
• Magnesium reaction with water:

  Very slow reaction, few bubbles of gas over long time
• Magnesium + Water = Magnesium Hydroxide + Hydrogen

  Mg + 2H2O = Mg(OH)2 +H2
• Calcium Reaction With Water:

  Sinks then rises, bubbles of gas, Ca eventually disappears, White precipitate forms, Heat produced. 


  Calcium + Water = Calcium Hydroxide + Hydrogen

  Ca + 2H2O = Ca(OH)2 + H2
• Sodium Reaction with Water:

  • Moves around on surface
  • Melts to form silvery ball
  • Bubbles of gas
  • Eventually disappears
  • Heat Produced
  • Colourless solution formed


  Sodium + Water = Sodium Hydroxide + Hydrogen

  2Na + 2H2O = 2NaOH + H2
• Potassium with Water:

  • Moves around on surface
  • Melts to form silvery ball
  • Lilac flame
  • Bubbles of gas
  • Eventually disappears
  • Heat produced
  • Colourless solution formed


  Potassium + Water = Potassium Hydroxide + Hydrogen

  2K + 2H2O = 2KOH + H2
• Magnesium with Steam:

  • Burns with a bright white light.
  • Forms white solid
  • Heat produced


  Magnesium + Steam = Magnesium Oxide + Hydrogen

  Mg + H2O = MgO + H2
• Aluminium with Steam:

  • Burns to form white solid
  • Heat produced


  Aluminium + Steam = Aluminium Oxide + Hydrogen

  2Al + 3H2O = Al2O3 + H2
• Zinc with Steam:

  • Glows
  • White solid formed
  • Heat produced


  Zinc + Steam = Zinc Oxide + Hydrogen

  Zn + H2O = ZnO + H2
• Iron with Steam:

  • Glows
  • Black solid formed


  Iron + Steam = Iron Oxide + Hydrogen

  3Fe + H2O = Fe3O4 + 4H2
• Potassium burns with a lilac flame producing a white solid
• Zinc burns producing a yellow solid which becomes white on cooling
• Iron burns with orange sparks producing a black solid
• Red-brown copper glows red and becomes covered with a black layer
• Displacement reactions:

  • More reactive metal will disappear, while less reactive will appear.
  • Solution may change colour.
  • Heat is produced.
• An ore is a rock which contains a metal compound from which the metal can be extracted.
• Reduction - removal of oxygen, gain of electrons