Electrolysis + extraction of aluminium

• What is electrolysis?

  The breakdown of a compound using an electrical current
• Where do positive charge ions go?


  Cathode
• Which is the negative electrode?

  Cathode
• What do positive charge ions receive?


  Electrons
• What happens to positively charged ions?

  They are reduced which is the loss of oxygen
• What is reduction?

  The loss of oxygen
• Where do negatively charged ions go?

  The anode
• What is the anode?

  The positive electrode
• What do negative ions lose?


  Electrons
• What happens to negative ions?


  They are oxidised
• What is oxidation?

  The gain of oxygen
• What substance is broken down?

  Electrolyte
• What is electrolyte?

  A substance that will conduct an electrical current
• What is an ion?

  An electrically charged particle
• What happens in electrolysis?

  Where ionic substances are decomposed into smaller substances when a current is passed through
• What is electricity?

  The flow of electrons
• What is required for electrolysis?

  The compound must contain ions
• What cannot act as electrolytes?

  Covalent compounds
• Why can’t covalent compounds be an electrolyte?

  They contain neutral atoms
• What must the ions be?

  Free to move
• When are ions freed?

  When an ionic substance is dissolved
• When are ionic substances dissolved?

  In water or by melting
• What is formed at the negative electrode (cathode)?


  Metal
• What is formed at the positive electrode (anode)?

  Non-metals
• What does a half-equation show?

  What happens at one of the electrodes
• What are electrons shown as?

  e-
• How are half-equations balanced?


  By adding or subtracting electrons equal to the number of charges (on the ions)
• What happens when metal ions gain electrons?

  They form neutral atoms
• What happens when non-metals lose electrons?

  They form neutral atoms
• What does OIL RIG stand for?

  Oxidation Is Loss Reduction Is Gain
• What does PANIC stand for?

  Positive Anode Negative Is Cathode
• How many electrons does Al3+ need?

  3
• What is a diatomic molecule?

  Two atoms covalently bonded together in a molecule
• What is aluminium?

  The most abundant metal on Earth
• How is aluminium expensive?


  Because of the amount of electricity used in the extraction process
• What is aluminium core called?

  Bauxite
• What is bauxite?

  Aluminium ore (Al2O3)
• Why is bauxite purified?

  To yield aluminium oxide so aluminium can be extracted
• How is aluminium extracted?


  By electrolysis
• Why is aluminium expensive to melt?

  It has a very high melting point (over 2000*C)