(i) Copper ions (Cu2+ ) and hydrogen ions H+ migrate to cathode.
(ii) Chloride ions (Cl– ) and hydroxyl ions OH– migrate to anode.
(iii) Copper ions (Cu2+ ) are likely to discharge at cathode, because their position is lower than hydrogen ions H+ in electrochemical series.
(iv) Cu2+ + 2e– ⟶ Cu
(v) Hydroxyl ions (OH– ) are likely to discharge at anode, because their position is lower than chloride ion (Cl– ) in electrochemical series.
(vi) 4OH– – 4e– ⟶ 2H2O + O2 (g)
(vii) The electrolyte gets decolourised. It is because, the blue colour of electrolyte is due to the presence of Cu2+ ions. As Cu2+ ions discharge at cathode, therefore their concentration in electrolyte decreases. Thus, gradually blue colour fades away.
(viii) In such a situation the copper atoms on copper anode ionise and enter into electrolyte. Thus, size of copper anode gradually decreases. This is not possible in case of graphite anode.
(ix) Hydrogen gas is liberated at cathode.