Which statement best describes electrode potential?

Which statement best describes electrode potential?

• A. The energy of electrons within the electrode material.
• B. The external work required to move electrons in a circuit.
• C. The thermodynamic tendency for electrons to flow, reflected in cell potential.
• D. The kinetic energy of electrons.

Answer: (C)

Electrode potential describes the thermodynamic tendency for electrons to flow at a half-cell, which is the driving force for charge transfer. This tendency is what shows up as the cell potential when two half-cells are connected: the greater the driving force, the larger the cell potential. The link between driving force and energy change is made clear by ΔG = -nF Ecell, so a positive cell potential corresponds to a spontaneous tendency for electron transfer under the given conditions. It is not the actual energy of electrons inside the electrode material, nor the external work needed to push electrons around a circuit, and it is not the kinetic energy of the electrons.

Electrode potential describes the thermodynamic tendency for electrons to flow at a half-cell, which is the driving force for charge transfer. This tendency is what shows up as the cell potential when two half-cells are connected: the greater the driving force, the larger the cell potential. The link between driving force and energy change is made clear by ΔG = -nF Ecell, so a positive cell potential corresponds to a spontaneous tendency for electron transfer under the given conditions. It is not the actual energy of electrons inside the electrode material, nor the external work needed to push electrons around a circuit, and it is not the kinetic energy of the electrons.