Question

Calculate the standard electrode potential (E°) for the redox reaction of the following half-reactions:Cu2+(aq) + 2e- → Cu(s) E° = +0.34 VFe3+(aq) + e- → Fe2+(aq) E° = +0.77 V

Answer 1

To calculate the standard electrode potential  E  for the redox reaction, we first need to balance the half-reactions and then combine them. The balanced half-reactions are:Cu2+ aq  + 2e-  Cu s  E = +0.34 V2 Fe3+ aq  + e-  Fe2+ aq   E = +0.77 VNow, multiply the second half-reaction by 2 to balance the number of electrons:2Fe3+ aq  + 2e-  2Fe2+ aq  E = +0.77 VNext, combine the half-reactions:Cu2+ aq  + 2Fe2+ aq   Cu s  + 2Fe3+ aq Now, we can calculate the standard electrode potential  E  for the redox reaction using the Nernst equation:E cell  = E cathode  - E anode In this case, the Cu2+/Cu half-reaction is the cathode  reduction  and the Fe3+/Fe2+ half-reaction is the anode  oxidation . Therefore:E cell  =  +0.34 V  -  +0.77 V  = -0.43 VThe standard electrode potential for the redox reaction is -0.43 V.