Question #9ba07

1 Answer
Oct 18, 2016

MnO2(s)+3Ag++2H2O(l)MnO4+3Ag(s)+4H+

Are charge and mass balanced?

Explanation:

Oxidation: Mn(IV)Mn(VII)

MnO2(s)+2H2O(l)MnO4+4H++3e (i) ;E=1.68V

Reduction: Mn(IV)Mn(VII)

Ag++eAg(s) (ii) ;E=0.80V

Overall: 1×(i)+3×(ii),

MnO2(s)+3Ag++2H2O(l)MnO4+3Ag(s)+4H+
;E=0.78V

I looked up the electrode potentials, and the reaction is NOT feasible. Reduction of Ag2+ would drive the reaction:

Ag2++2eAg(s) (iii) ;E=1.99V