174. The standard reduction potential for the Zn²⁺ (aq) | Zn(s) half cell is 0.76 V. Write the reactions occurring at the electrodes when coupled with standard hydrogen electrode (SHE).

Can a nickel spatula be used to stir the solution of CuSO₄? Support your answer with reason. (E°_Ni2+/Ni = – 0.25 V, E°_Cu2+/Cu = + 0.34 V)

Calculate the e.m.f. of the cell in which the reaction is
$$\begin{gathered} \mathrm{Mg}\left(\mathrm{s}\right) + 2{\mathrm{Ag}}^{+}\left(\mathrm{aq}\right) \to {\mathrm{Mg}}^{2+}\left(\mathrm{aq}\right) + 2\mathrm{Ag}\left(\mathrm{s}\right) \\ \mathrm{When} \left[{\mathrm{Mg}}^{2+}\right] = 0.130 \mathrm{M} \\ \mathrm{and} \left[{\mathrm{Ag}}^{+}\right] = 1.0 \times {10}^{-4}\mathrm{M}. \\ [\mathrm{Given} {\mathrm{E}}_{{\mathrm{Mg}}^{2+}/\mathrm{Mg}} = -2.37 \mathrm{V} \mathrm{and} \mathrm{E}{°}_{{\mathrm{Ag}}^{+}/\mathrm{Ag}} = 0.80 \mathrm{V}] \end{gathered}$$

Calculate the cell emf at 25° C for the following cell:
Ni(s) | Ni²⁺ (0.01 M) || Cu²⁺ (0.1 M) | Cu(s)
[Given E°_Ni²⁺/Ni = – 0 25 V, ^E° Cu = + 0.34 V, 1 F = 96500]
Calculate the maximum work that can be accomplished by operation of this cell.

The emf of a cell corresponding to the reaction
Zn(s) + 2H⁺ (aq) → Zn²⁺ (0.1 M) + H²(g) (1 atm) is 0.28 V at 15° C.Write the half cell reactions and calculate the pH of the solution at the hydrogen electrode.