Electrolysis

• What is electrolysis?

  • Electric current is passes through an electrolyte
  • Electrolyte causes ions to move to the electrodes, where they form elements
• What is an electrolyte?

  A liquid or solution that contains ions & can conduct electricity
• What is the negatively charged electrode?

  Cathode
• What is the positively charged electrode?

  Anode
• Where do positive ions (metal) move during electrolysis?


  Cathode
• Where do negative ions (non-metal) move during electrolysis?


  Anode
• What happens to non-metal ions at the anode?

  • They are oxidised (lose electrons)
  • Forms elements
• What happens to metal ions at the cathode?

  • They are reduced (gain electrons)
  • Forms elements
• What is a displacement reaction?

  More reactive element takes the place of a less reactive element
• Where can electrolysis occur?

  • Aqueous solutions
  • Molten compounds
• What is the reactivity series?

  • Potassium
  • Sodium
  • Calcium
  • Magnesium
  • Aluminium
  • Carbon
  • Zinc
  • Iron
  • Lead
  • Hydrogen
  • Copper
  • Silver
  • Gold
• What metals can electrolysis extract?

  Metals more reactive than carbon
• How would you use electrolysis to extract aluminium?

  • Anode burns away
  • Oxygen produced reacts with carbon oxide, producing CO2 gas
  • Aluminium left over