Electrolysis- Paper 1 Flashcards
What is used in electrolysis to cause the reaction?
Electricity
What happens during electrolysis?
electric current passes through electrolyte, ions move towards electrode where they react and the compound decomposes.
What is an electrolyte?
Molten/Dissolved ionic compound
Where will the positive and negative ions go?
Positive ions go to Cathode (negative elctrode) Negative ions go to Anode (positive electrode)
What happens then, at the anode and cathode?
Cathode(-ve) GAIN ELECTRONS (they are reduced)
Anode(+ve) LOSE ELECTRONS (they are oxidised)
Why can’t solid ionic compounds conduct electricity?
Due to the strong electrostatic forces of attractions, meaning the ions aren’t free to move.
Why can a melted/ dissolved ionic compound conduct electricity?
As the forces of attraction are broken, meaning the ions are free to move.
What is an electrolyte?
A liquid/ dissolved ionic solution that conducts electricity.
Why is electrolysis an expensive process?
Melting the compounds requires a large amount of energy.
A lot of energy is required to produce the electric current
What does aqueous mean?
Dissolved in water
What ions are split from water?
H+ (hydrogen ion)
OH- (hydroxide ion)
How are the electrodes made to not react with the chemicals?
They are inert, by using platinum
How are the electrodes made to not react with the chemicals?
They are inert, by using platinum as the electrode
What are the half equations at the electrodes for aqueous solutions?
(copper sulfate)
Cathode;
Cu2+ + 2e- —-> Cu
Anode;
4OH- —-> O2 + 2H2O + 4e-
What forms at the anode if there is a halide ion present?
THE HALOGEN WILL BE PRODUCED AT THE ANODE
