Electrolysis of aqueous solutions

• CuSO4 solution :

  • Metal produced at cathode if it is less reactive that H2
  • O2 and H2O produced at anode if no halide ions are present - 4OH- -> O2 + 2H2O + 4e-

  NaCI solution :

  • Halogen produced at anode if halide ions are present
  • H2 produced at cathode if metal is more reactive than H2 - 2H+ + 2e- -> H2 .