Electrolysis Flashcards
What is an electrolyte?
(Ionic) liquids and solutions are able to conduct electricity
What is electrolysis?
the use of electrical current to break down compounds containing ions into their constituent elements
What happens during electrolysis?
Positively charged ions move to the negative electrode (the cathode),
negatively charged ions move to the positive electrode (the anode).
Ions are discharged at the electrodes producing elements.
which electrode are metals produced at?
cathode
which electrode are non-metals produced at?
anode
Why is electrolysis an expensive process?
because it requires lots of heat and electrical energy
Metals can be extracted from ________ using electrolysis
molten compounds
When is electrolysis used to extract metals?
if the metal is too reactive to be extracted by reduction with carbon or if the metal reacts with carbon.
Why are large amounts of energy needed for electrolysis
to melt the compounds and to produce the electrical current
How is Aluminium oxide’s melting point reduced?
cryolite is mixed with aluminium oxide
Why is does Aluminium oxide melting point need to be reduced?
because high melting point means that a lot of energy would need to be produced in order to melt aluminium oxide which is expensive
the positive aluminium ions (A3+) will form at which electrode?
the cathode
- it will then sink to the bottom of the electrolysis tank
the oxygen ions of aluminium oxide will form at which electrode
the anode
Why does the anode in aluminium oxide electrolysis need to be replaced regularly?
because oxygen will react with the carbon which will wear the anode away
What happens at the cathode in electrolysis of aqueous solutions?
- hydrogen is produced if the metal is more reactive than hydrogen
- A solid layer of the pure metal will be produced if the metal is less reactive than hydrogen
