Question

Identify the substance liberated at each electrode during the electrolysis of AgNO3 with inert electrodes.

I know that Ag is liberated at the cathode, but how about the anode?

Thanks in advance!

Answer 1

For aqueous electrolysis of AgNO₃, water would dominate at both electrodes. Generally, for an aqueous electrolytic process whose chemical reactions are driven by a battery …

The more negative Reduction Potential dominates at the cathode (site of reduction)
Ag⁺ + eˉ => Agᵒ ; Eᵒ = +0.80 volt
H₂O + 2eˉ => H₂ + 2OHˉ; Eᵒ = -0.83 volt => Dominate Rxn at Cathode

The more positive Reduction Potential dominates at the anode (site of oxidation)
NO₃ˉ + 4H⁺ + 3eˉ => NO + 2H₂O; Eᵒ = +0.96 volt
2H₂O => O₂ + 4H⁺ + 4eˉ ; Eᵒ = +1.23 volts => Dominate Rxn at the Anode

The net cell reaction would be 2H₂O => O₂ + 2H₂

Just an FYI, one should avoid considering melt electrolysis of nitrate systems => explosive! :-o