Question

What is the net cell reaction for the cobalt-silver voltaic cell? express your answer as a chemical equation?

Answer 1

Answer: The net ionic equation for the cobalt-silver voltaic cell is $Co(s)+3Ag^+(aq.)\rightarrow Co^{3+}(aq.)+3Ag(s)$

Explanation: In cobalt-silver voltaic cell, one half of the cell consists of cobalt electrode immersed in $Co(NO_3)_3$ solution ( which means that $Co^{3+}$ are present in the solution) and other half of the cell consists of the Ag electrode immersed in $AgNO_3$ solution ( which means that $Ag^+$ is present in the solution)

The two electrodes are joined by the copper wire. The cobalt electrode acts as an anode and the silver electrode acts a  cathode.

At anode, oxidation reaction takes place and at cathode, reduction reaction takes place.

At Anode :                    $Co(s)\rightarrow Co^{3+}(aq.)+3e^-$

At Cathode:                   $[Ag^+(aq.)+e^-\rightarrow Ag(s)]\times 3$

Net ionic equation:   $Co(s)+3Ag^+(aq.)\rightarrow Co^{3+}(aq.)+3Ag(s)$