J.R. S. answered • 05/10/20
Ph.D. University Professor with 10+ years Tutoring Experience
No. You don't have to use Gibbs free energy for this problem. The reason is that this is a redox reaction, and if you are familiar with voltaic/galvanic cells, you'll recognize this. So, as you suggest, you can use the Eº of the cell and if it is positive, the reaction will be spontaneous.
As it turns out from looking at the table of standard reduction potentials, the reaction, as written, is not spontaneous.
Fe3+ + e- ==> Fe2+ Eº = 0.77
Ag+ + e- ==> Ag(s) Eº = +0.80 V
Fe3+ + Ag(s) ==> Fe2+ + Ag+ Eº = -0.03 V
J.R. S.
05/10/20
Ayla S.
Ok thank you very much :)05/10/20
J.R. S.
05/10/20
J.R. S.
05/11/20
Ayla S.
Hi, yes I removed it because I realised I was half asleep when writing that comment and that I was wrong. Thank you for your answer :)05/11/20
Ayla S.
But I do wonder now that I see that the E0 for the iron undergoing reduction is 0.77 V, but the silver ion is undergoing oxidation so the E0 should be -0.80 V?05/11/20
Ayla S.
Oh I see thanks! I would just like to ask you, from where do you get the E0 values? I would like to use that table as well because in my chem. book table the Fe3+ reduction is not there. Thank you :)05/10/20