C2 Electrolysis
Name ________________________
Class
_______
Teacher ________________
Double C2 – Electrolysis
What is electrolysis?
Electrolysis is the splitting up of an ionic compound by using
electricity.
Ionic compounds contain positive A________ and negative
C________, held together in an I_______ L________.
Why do ionic substances not conduct
electricity when solid?
__________________________________
__________________________________
When ionic substances are melted or dissolved the ions are
_______ to move and carry the electrical __________.
What is the definition of electrolysis?
_________________________________________________
_________________________________________________
What is an electrolyte?
_________________________________________________
_________________________________________________
When 2 graphite electrodes are
placed in the electrolyte and
electricity flows, the ions will
m________ to the oppositely
charged electrode and the
electrolyte will d__________.
The positive electrode is called the __________ and attracts
_________ ions (called _________)
The negative electrode is called the _________ and attracts
_________ions (called _______).
What are the properties that all electrodes must have?
1) They are good conductors of ______________.
2) They must be _______ which means they perform electrolysis
but don’t ______ themselves.
Good examples are P_________ (expensive) and G_________.
Industrial electrolysis of Aluminium
Aluminium is not found n_________. It is found as the compound
A_______ O________ (_________) in an ore called B_________.
The bauxite is purified to form Alumina (pure __________
_________) which can be decomposed by e______________.
For electrolysis to occur, the ions must be
free to m______. Alumina must be
melted but has a very high m________
point which massively increases the cost.
To reduce the mpt (and increase the
conductivity) the alumina is dissolved in
C__________! This reduces the mpt to
9000C and saves energy and money.
What happens at the cathode?
What happens at the anode?
Why do the anodes need to be regularly replaced?
_________________________________________________
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What is the advantage of the crust that on forms on top?
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Why is electrolysis so expensive?
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Why should we recycle Aluminium?
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