Extracting metals

• Electrolysis

  Breakdown of a compound using an electric current.
• Electrolysis example 


  1. Aluminium oxide dissolved in molten cryolite

  2. Current passed through the mixture

  3. Aluminium ions attracted to cathode, forming aluminium

  4. Oxide ions attracted to anode, forming oxygen gas
• Phytoextraction


  Biological method of metal extraction that uses plants
• Phytoextraction


  1. Metal compounds absorbed by roots

  2. Plant concentrates metal compounds in its shoots and leaves

  3. Plants burned

  4. Ash contains metal compounds
• CAThode attracts positive ions (cations) but has a negative charge.
• ANode attracts negative ions (anions) but has a positive charge.
• At the ANODE ions are oxidized and lose electrons
• At the CATHODE, ions are reduced but gain electrons.