Overpotential is defined as what, and what are its three main components?

• A. Overpotential is the potential difference between the anode and cathode at equilibrium; Activation and diffusion.
• B. Overpotential is the extra potential beyond equilibrium needed to drive the reaction; Activation, concentration, and ohmic components.
• C. Overpotential is the potential lost due to corrosion; Thermal, chemical.
• D. Overpotential is the energy stored in the double layer; Capacitance only.

Answer: (B)