Extracting Aluminium

Question 1

What does aluminium originally exist as?

Answer 1

A compound with oxygen known as aluminium oxide

Question 2

Where do aluminium come from?

Answer 2

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Question 3

Why does aluminium have to be molten during electrolysis to extract aluminium from the compound?

Answer 3

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Question 4

What is the melting point of aluminium oxide?

Answer 4

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Question 5

What is used to decrease the melting point ?

Answer 5

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Question 6

Why is the melting point decreased?

Answer 6

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Question 7

Draw and label the electrolysis diagram for aluminium?

Answer 7

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Question 8

What happens during electrolysis of aluminium ?

Answer 8

The aluminium in the aluminium oxide dissolved in molten cryolite moves towards the cathode as opposite charges attract meaning that it loses 3 electrons at the cathode meaning that is being reduced so it becomes an aluminium atom whereas the oxygen moves to the anode and gains 2 electrons to complete its outer shell forming an oxygen atom but also because the anode is is made of graphite it also produces carbon dioxide gas. The pure aluminium sinks to the bottom and is released as molten aluminium through the tapping hole.

Question 9

Why does the anode need to be replaced regularly ?

Answer 9

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Question 10

What are the two half equations for aluminium and oxygen?

Answer 10

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