Determine the products made when a current is passed through a salt solution
Step 1:
Place carbon electrodes (inert) in a solution of the salt to be electrolysed, ensuring they don’t touch. Connect to the terminals of a battery or power supply
What is a negative electrode?
Cathode
What is a positive electrode?
Anode
Step 2:
The solution contains H+ and OH- ions. If sodium chloride solution, also Na+ and Cl- ions.
Step 3:
if the metal ion is more reactive than hydrogen (like sodium), it will stay in solution, and hydrogen will be reduced at the cathode to make H2 gas.
If not, the metal will be reduced instead (e.g. copper).
Step 4:
If the non-metal ion is a halide (Cl, Br, I), it will be oxidised at the anode (Cl, will be made here -proven by bleaching blue litmus paper). If it's not a halide (e.g. sulphate, SO2-) oxygen gas is made at the anode instead
