1. Making aluminium

2. Keywords and big picture starter
Bauxite, Aluminium oxide, graphite, cryolite, electricity, molten, malleable, strong, low density and unreactive.
Take a look at the bauxite ore and aluminium foil shown on the desk
think of 5 facts and uses about aluminium
Use the keywords above to help

3. THE ELECTROLYSIS OF ALUMINIUM FROM ALUMINIUM OXIDE
L.O. Explain with diagrams – the extraction of aluminium from bauxite
Evaluate the importance of conditions needed for extraction of aluminium

4. Explain with diagrams – the extraction of aluminium from bauxite
Add as much detail to the picture of this electrolytic cell to explain how aluminium
is extracted
What do the red, grey and black areas represent?
What do the yellow areas represent?
What is being oxidised?
4. What is being reduced?
5. Which way will electrons flow and why?
6. How can you summarise this process using half equations

5. start Explain with diagrams – the extraction of aluminium from bauxite
What do the red, grey and black areas represent?
What do the yellow areas represent?
What is being oxidised?
What is being reduced?
Which way will electrons flow and why?
How can you summarise this process using half equations
Explain with diagrams – the extraction of aluminium from bauxite
start

6. EXTRACTION OF ALUMINIUM
Help 1
THE CELL CONSISTS OF A

7. EXTRACTION OF ALUMINIUM
Help 2
CARBON ANODE
THE CELL CONSISTS OF A CARBON ANODE

8. EXTRACTION OF ALUMINIUM
Help 3
STEEL CATHODE
CARBON LINING
THE CELL CONSISTS OF A CARBON LINED STEEL CATHODE (iron and carbon)

9. MOLTEN ALUMINA and CRYOLITE
EXTRACTION OF ALUMINIUM
Help 4
MOLTEN ALUMINA and CRYOLITE
ALUMINA IS DISSOLVED IN MOLTEN CRYOLITE Na3AlF6
SAVES ENERGY - the mixture melts at a lower temperature

10. MOLTEN ALUMINA and CRYOLITE
EXTRACTION OF ALUMINIUM
Help 5
MOLTEN ALUMINA and CRYOLITE
ALUMINA IS DISSOLVED IN MOLTEN CRYOLITE Na3AlF6
aluminium and oxide ions are now free to move

11. EXTRACTION OF ALUMINIUM
Help 6
POSITIVE ALUMINIUM IONS ARE ATTRACTED TO THE NEGATIVE CATHODE
CARBON CATHODE
Al e- Al
EACH ION PICKS UP 3 ELECTRONS AND IS DISCHARGED

12. O2- O + 2e- NEGATIVE OXIDE IONS ARE ATTRACTED TO THE POSITIVE ANODE
EXTRACTION OF ALUMINIUM
Help 7
NEGATIVE OXIDE IONS ARE ATTRACTED TO THE POSITIVE ANODE
CARBON ANODE
O O e-
EACH ION GIVES UP 2 ELECTRONS AND IS DISCHARGED

13. Electrons will flow from most reactive to least reactive electrode
EXTRACTION OF ALUMINIUM
Help 8
ELECTRONS
CARBON ANODE
CARBON CATHODE
Electrons will flow from most reactive to least reactive electrode

14. EXTRACTION OF ALUMINIUM
Help 9
ELECTRONS
OXIDATION (LOSS OF ELECTRONS) TAKES PLACE AT THE ANODE
CARBON ANODE
ANODE OXIDATION

15. EXTRACTION OF ALUMINIUM
Help10
ELECTRONS
OXIDATION (LOSS OF ELECTRONS) TAKES PLACE AT THE ANODE
REDUCTION (GAIN OF ELECTRONS) TAKES PLACE AT THE CATHODE
CARBON CATHODE
ANODE OXIDATION
CATHODE REDUCTION

16. Electrons will flow from most reactive to least reactive electrode
finish
ELECTRONS
OXIDATION (LOSS OF ELECTRONS) TAKES PLACE AT THE ANODE
CARBON ANODE
REDUCTION (GAIN OF ELECTRONS) TAKES PLACE AT THE CATHODE
CARBON CATHODE
ANODE 2O O e OXIDATION
CATHODE Al e Al REDUCTION
ALUMINA IS DISSOLVED IN MOLTEN CRYOLITE Na3AlF6
aluminium and oxide ions are now free to move
SAVES ENERGY - the mixture melts at a lower temperature

17. THE CARBON ANODES REACT WITH THE OXYGEN TO PRODUCE CARBON DIOXIDE
Evaluate the importance of conditions needed for extraction of aluminium
BAUXITE aluminium ore
Bauxite contains alumina (Al2O3 aluminium oxide) plus impurities such as iron oxide – it is purified before use.
CRYOLITE Aluminium oxide Al2O3 has a very
high melting point.
Adding cryolite Na3 AlF6 lowers the melting point and saves energy.
THE CARBON ANODES REACT WITH THE OXYGEN TO PRODUCE CARBON DIOXIDE
THE CARBON ANODES HAVE TO BE REPLACED AT REGULAR INTERVALS, THUS ADDING TO THE COST OF THE EXTRACTION PROCESS

18. THE IMPORTANCE OF ALUMINIUM
USES OF ALUMINIUM
THE IMPORTANCE OF ALUMINIUM
LOW DENSITY AND OVERHEAD CABLES
ELECTRICAL CONDUCTIVITY
LOW DENSITY AIRCRAFT BODIES
needs to be an alloyed with
other metals for extra strength
GOOD HEAT CONDUCTIVITY SAUCEPANS

19. THE IMPORTANCE OF ALUMINIUM
USES OF ALUMINIUM
THE IMPORTANCE OF ALUMINIUM
LOW DENSITY AND OVERHEAD CABLES
ELECTRICAL CONDUCTIVITY
LOW DENSITY AIRCRAFT BODIES
needs to be an alloyed with
other metals for extra strength
GOOD HEAT CONDUCTIVITY SAUCEPANS
Syllabus wants you to quote theses uses and reasons

20. Here are the answers, what are the questions?....
Think of the questions related to the answers found on the worksheet provided

21. Quiz questions next!