Chemistry C6 - Electrolysis Flashcards
What are the two types of electrolysis?
molten and aqueous
What does electrolysis mean?
Splitting up a substance using electricity
What does discharge mean?
- When an ion gains or loses electrons at the electrode
What does molten mean?
Melted
What is a cathode?
A negative electrode
What is an anode?
A positive electrode.
Where is the metal produced during molten electrolysis?
At the cathode (negative electrode)
Where is the non-metal produced during molten electrolysis?
At the anode (positive electrode)
What is an electrolyte
The substance being electrolysed.
When is electrolysis used to extract metals?
When the metal is too reactive to use carbon.
Why are metals produced by electrolysis expensive?
It takes lots of energy to melt the substance and produce the electricity.
Outline the electrolysis to produce aluminium.
A molten mixture of aluminium oxide and cryolite is electrolysed using a carbon anode.
What do the ions discharged during aqueous electrolysis depend on?
The reactivity of the species present.
When is hydrogen produced at the cathode?
When the metal is more reactive than hydrogen.
What is produced at the anode?
Halogens if the solution contains halide ions.
