Galvanic Cells — Prelims Questions

For the following half-reactions and their standard reduction potentials: $Zn^{2+}(aq) + 2e^- \rightarrow Zn(s) \quad E^\circ = -0.76\,\text{V}$ $Ag^+(aq) + e^- \rightarrow Ag(s) \quad E^\circ = +0.80\,\text{V}$ Which statement is correct for a galvanic cell constructed using these two half-cells?

A galvanic cell is set up with the reaction: $2Cr(s) + 3Cd^{2+}(aq) \rightarrow 2Cr^{3+}(aq) + 3Cd(s)$. If $E^\circ_{Cr^{3+}/Cr} = -0.74\,\text{V}$ and $E^\circ_{Cd^{2+}/Cd} = -0.40\,\text{V}$, calculate the standard cell potential ($E^\circ_{cell}$).

For the reaction $Ni(s) + 2Ag^+(aq) \rightarrow Ni^{2+}(aq) + 2Ag(s)$, the standard cell potential $E^\circ_{cell} = +1.05\,\text{V}$. Calculate the Gibbs free energy change ($\Delta G^\circ$) for this reaction at $298\,\text{K}$. (Given: $F = 96485\,\text{C mol}^{-1}$)

A galvanic cell is represented as $Zn(s) | Zn^{2+}(aq, 0.1\,\text{M}) || Cu^{2+}(aq, 1.0\,\text{M}) | Cu(s)$. Given $E^\circ_{cell} = +1.10\,\text{V}$ for the Daniell cell, calculate the cell potential ($E_{cell}$) at $298\,\text{K}$.

Which of the following statements about the salt bridge in a galvanic cell is INCORRECT?

For a galvanic cell, if the standard cell potential ($E^\circ_{cell}$) is positive, what can be inferred about the standard Gibbs free energy change ($\Delta G^\circ$) and the equilibrium constant ($K_{eq}$)?