Consider the electrochemical cell : (APP)Zn (s)/Zn2+ (aq) // Cu2+ (aq)

1.	Consider the electrochemical cell : (APP)Zn (s)/Zn2+ (aq) // Cu2+ (aq)/Cu.It has an electrical potential of 1.1 V when concentration of Zn2+ and Cu2+ ions is unity.State the direction of flow of electrons and also specify if Zinc and Copper are deposited or dissolved at their respective electrodes.When:(a) An external opposite potential of 0.8 V is applied.(b) An external opposite potential of 1.1 V is applied.(c) An external opposite potential of 1.4 V is applied.
Answer» (a) Electrons flow from Zn rod to Cu rod. (b) No flow of electrons and current. No change observed at Zinc and Copper electrodes (system is equilibrium). (c) Electrons flow from Cu rod to Zn rod. Zinc is deposited and Copper gets dissolved.

Consider the electrochemical cell : (APP)Zn (s)/Zn2+ (aq) // Cu2+ (aq)/Cu.It has an electrical potential of 1.1 V when concentration of Zn2+ and Cu2+ ions is unity.State the direction of flow of electrons and also specify if Zinc and Copper are deposited or dissolved at their respective electrodes.When:(a) An external opposite potential of 0.8 V is applied.(b) An external opposite potential of 1.1 V is applied.(c) An external opposite potential of 1.4 V is applied.

Answer»

(a) Electrons flow from Zn rod to Cu rod.

(b) No flow of electrons and current. No change observed at Zinc and Copper electrodes (system is equilibrium).

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