Question

The following electrochemical cell has been set-up:

Pt₁|Fe³⁺|Fe²⁺(1M)||Ce⁴⁺ | Ce³⁺ (1M)|Pt₂ 

E°_{Fe3+ /Fe2+} =0.77 V and E°_Ce4+/Ce3+ = 1.61 V

If an ammeter is connected between the two platinum electrodes, predict the direction of flow of current. Will the current increase or decrease with time?

Answer 1

SRP of Fe > SRP of Ce

⇒ Fe acts as anode and Ce acts as cathode

Hence, flow of current is from cathode to anode (right to left) Current will decrease with time.