Question

$Eº$ value of $Ni^{2 +}/Ni$ is $- 0.25$V and $Ag^{+}/Ag$ is $+ 0.80V$ if a cell is made by taking the two electrodes what is the Feasibility of the reaction?

• A. Since $Eº$value for the cell will be positive redox reaction is feasible.
• B. Since $Eº$ value for the cell will be negative redox reaction is not feasible.
• C. Ni cannot reduce $Ag^{+}$ to Ag hence reaction is not feasible.
• D. Ag can reduce $Ni^{2 +}$ to Ni hence reaction is feasible

Answer 1

Answer: (A)

Since $Eº$value for the cell will be positive redox reaction is feasible.

Answer 2

The cell reaction will be

$Ni_{(s)} + 2A{g^{+}}_{(aq)} \rightarrow N{i^{2 +}}_{(aq)} + 2Ag_{(s)}$

$Eº_{Cell} = E_{cathode} - E_{anode}$

$= 0.80 - ( - 0.25) = 1.05V$

$\Delta Gº = - nFEº_{cell}$

As k$Eº_{cell} = + ve,$

$\Delta Gº = - ve$ Hence reaction is feasible