Reactivity Series and Standard Potentials

Cyclic voltammetry (CV) is a fundamental electrochemical technique used to study redox reactions. In this demonstration, a ferricyanide solution is analyzed using a potentiostat with a carbon electrode. The potential is scanned from −200 mV to +600 mV and back at 100 mV/s, generating a characteristic voltammogram. Key equations explain the response: the Tafel equation (kinetic control at low potentials), Randles-Sevcik equation (diffusion-limited peak current), and Cottrell equation (current decay due to reactant depletion). The forward scan oxidizes ferrocyanide to ferricyanide; the reverse scan reduces it back. CV reveals reaction reversibility and kinetics, with scan rate influencing peak clarity. This method is vital for electrochemical research and assay development.