RP 3 - Electrolysis

• electrolysis of copper (II) chloride solution

  1. first pour approx 50cm3 of copper (II) chloride solution in a beaker
  2. place a plastic petri dish with two holes over the beaker
  3. insert a carbon graphite rod into each hole - electrodes : carbon graphite unreactive, so these electrodes are inert (must not touch eachother and would produce short-circuit)
  4. add crocodiles leads to the rods and connect the rods to the terminals of a low-voltage power supply - select 4V on power supply and turn it on
  5. CATHODE : coated with copper (less reactive than H2)
  6. ANODE: bubbles of gas/smell of chlorine (halide ion)
• electrolysis of sodium chloride solution

  1. approx 50cm3 of sodium chloride solution into the beaker
  2. turn on low voltage power supply
  3. ANODE - bubbles of CHLORINE GAS (halide ion !)
  4. CATHODE - gas bubbles of HYDROGEN (hydrogen less reactive than sodium)