What might cause a shift in the peak potentials during a cyclic voltammetry experiment?

In cyclic voltammetry, the peak potentials are sensitive to a variety of experimental conditions, meaning that changes in solvent type or temperature can significantly affect the electrochemical behavior of the system being studied.

When changing the solvent type, the dielectric constant and the viscosity of the solvent can influence the solvation of ions and molecular species involved in the redox processes. Different solvents can stabilize or destabilize certain oxidized or reduced forms of the analyte, which can lead to shifts in peak potentials due to changes in energy levels or the kinetics of electron transfer reactions.

Altering the temperature can also impact the peak potentials. As temperature increases, reaction kinetics often improve, allowing for faster electron transfer. Additionally, temperature changes can affect the solubility and mobility of reactants and products in the solution, which may result in shifts in peak potentials as well.

Both of these factors—solvent type and temperature—can alter the electrochemical environment and the thermodynamics of the redox processes, leading to observable changes in the peak potentials during cyclic voltammetry experiments. Thus, the correct answer being that both a change in solvent type and a change in temperature can cause shifts in peak potentials is supported by the dependence of electrochemical behavior on these variables.