aluminium oxide

• What process is used to extract reactive metals from their oxides?

  Electrolysis
• Why do metals often exist as oxides?

  Because they react with oxygen in the environment
• What is the first step to isolate pure metal from its oxide?

  Reduce the metal in the oxide
• How does carbon reduce metal oxides?

  Carbon displaces the metal in the metal oxide
• Which metals can be reduced using carbon?

  Zinc, iron, and copper
• Why is electrolysis more expensive than reduction with carbon?

  It requires a lot of energy
• What is the role of an electrolyte in electrolysis?

  It allows ions to move freely
• Why can't aluminium oxide be used directly for electrolysis?

  Because it is solid and the ions are fixed in place
• What must be done to bauxite before electrolysis can occur?

  It must be turned into molten aluminium oxide
• What mineral is mixed with aluminium oxide to lower its melting point?

  Cryolite
• What is the melting point of aluminium oxide?

  Over 2000 degrees Celsius
• What equipment is needed for the electrolysis of molten aluminium oxide?

  A beaker, electrodes, and a power source
• What are the two types of electrodes used in electrolysis?

  Anode and cathode
• What happens to oxygen ions at the anode during electrolysis?

  They lose electrons and form oxygen atoms
• What is produced at the cathode during the electrolysis of aluminium oxide?

  Molten aluminium metal
• What is the half equation for the reaction at the anode?

  Oxygen ions go to form oxygen atoms plus electrons
• What mnemonic helps remember the difference between oxidation and reduction?

  Oil rig
• What is the overall equation for the electrolysis of aluminium oxide?

  Aluminium oxide goes to form aluminium and oxygen
• What are the steps involved in the electrolysis of aluminium oxide?

  1. Purify aluminium oxide from bauxite
  2. Mix with cryolite to lower melting point
  3. Melt the mixture to create molten aluminium oxide
  4. Set up electrolysis equipment with electrodes and power source
  5. Conduct electrolysis to produce aluminium and oxygen
• What happens at each electrode during the electrolysis of aluminium oxide?

  • Anode: Oxygen ions lose electrons and form oxygen gas
  • Cathode: Aluminium ions gain electrons and form molten aluminium
• What are the characteristics of the electrolysis process?

  • Requires an electrolyte
  • Involves the movement of ions
  • Produces pure elements from ionic compounds
  • Involves oxidation and reduction reactions
• 2Al(2)O(3) -> 4AL + 3O(2)
• • Al3+ + 3e- ->Al
  • 2O2- -> O2 + 4e-