General Chemistry Electrochemistry Math Question 3

Question

Use a table of standard thermodynamic values to predict the standard cell potential at 80 C:

Cu(s) | CuSO₄ | | AgNO₃ | Ag(s)

Answer 1

The approach to this problem will depend to a large extent on the table of thermodynamic values that are provided/available. Also, the question makes little sense because you can't really have a "standard cell potential" at 80ºC since the standard cell potential is defined at 25ºC or 298K.

Cu²⁺ + 2e- ==> Cu Eº = +0.34V ... anode = oxidation

Ag⁺ + e- ==> Ag Eº = +0.8V ... cathode = reduction

2Ag⁺ + Cu ==> 2 Ag + Cu²⁺ ... overall reaction and transfer of 2 moles electrons

Depending on what the question is really asking, and assuming values of ∆G are provided, one could use

∆Gº = -RT ln K to find K and then use Eº = RT/nF ln K. But note that the conditions would be 1 M of Cu²⁺ and Ag⁺ but the temperature of 80ºC is not standard.