What are electrolytes
ionic compounds in the molten state or dissolved in water
How do ions move in electrolysis
positive cations migrate to the negatively charged cathode
negative anions migrate to the positively charged anode
Describe electrolysis
a process in which electrical energy from a direct current supply, decomposes electrolytes
What is an electrolyte
liquids through which a current can flow
When a solution is electrolysed what occurs at the cathode
In a mixture of ions the H^+ and the other positive ions are present. It is the ion which is lower in the reactivity series that will be discharged and reduced
When a solution is electrolysed what occurs at the anode
If the solution contains a halide ions, they are discharged and released from the anode, otherwise if the solution contains other negative ions like sulphate and nitrate oxygen is released at the anode
What occurs at the cathode
reduction
What occurs at the anode
oxidation
What happens when copper sulphate is electrolysed with copper electrodes
The mass of the cathode increases as copper is deposited there and the mass of the copper anode decreases as copper is removed
How can copper be electrolysed to purify it
The cathode is a small piece of pure copper and the anode is a large piece of impure copper. The copper ions move to the cathode and as copper is likely the least reactive it is produced at the cathode
the impurities move towards the anode and are deposited there
How is aqueous sulphuric acid electrolysed
with a Hofmann Voltameter
oxygen and hydrogen are produced
What is formed when copper is electrolysed with inert electrodes
Copper at the cathode and oxygen at the anode
