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 purpose of reduction in metal extraction?

  To remove oxygen and isolate pure metal
• Which method is used to reduce metals less reactive than carbon?

  Reduction with carbon
• 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 does electrolysis do to ionic compounds?

  Separates them into pure elements
• What is required for electrolysis to occur?

  An electric current through an electrolyte
• Why can't solid aluminium oxide be used in electrolysis?

  Because the ions are fixed in place
• What must be done to bauxite before electrolysis?

  Turn it 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 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 the overall reaction at the cathode during electrolysis?

  Aluminium ions gain electrons to form aluminium
• What mnemonic helps remember oxidation and reduction?

  Oil rig
• What does oxidation refer to in electrolysis?

  Loss of electrons
• What does reduction refer to in electrolysis?

  Gain of electrons
• What is the overall equation for the electrolysis of aluminium oxide?

  Aluminium oxide forms aluminium and oxygen
• What are the steps to extract aluminium from bauxite using electrolysis?

  1. Purify aluminium oxide from bauxite
  2. Mix aluminium oxide with cryolite
  3. Melt the mixture to create molten aluminium oxide
  4. Set up electrolysis equipment with electrodes
  5. Pass electric current through the molten electrolyte
• What are the products of the electrolysis of aluminium oxide?

  • Aluminium (liquid)
  • Oxygen (gas)
• What is the significance of the melting point in the electrolysis process?

  • Must be molten for ions to move
  • High melting point requires energy to lower