Electrochemical Cells and Redox Reactions (4C) Practice Test

A student builds a concentration cell using identical Cu electrodes: Cu(s)|Cu$^{2+}$(0.10 M)||Cu$^{2+}$(1.0 M)|Cu(s) at 25°C. Assume ideal behavior and that the salt bridge maintains electroneutrality. Which outcome would be expected in this electrochemical cell?

In a simplified model of mitochondrial electron transport, a researcher constructs a galvanic cell at $25^\circ\text{C}$ using an Fe$^{3+}$/Fe$^{2+}$ couple (to mimic cytochrome behavior) and a Cu$^{2+}$/Cu couple. Solutions are 1.0 M for all ions. Standard reduction potentials: Fe$^{3+}$ + e$^-$ $\rightarrow$ Fe$^{2+}$, $E^\circ=+0.77,\text{V}$; Cu$^{2+}$ + 2e$^-$ $\rightarrow$ Cu(s), $E^\circ=+0.34,\text{V}$. Based on the setup, which conclusion is most consistent with the electrochemical process?