Electrolytic cell reaction which would not occur spontaneously otherwise. A galvanic cell can be considered an electrolytic cell acting in reverse. While electrolytic cells convert electrical energy into chemical energy, galvanic cells convert chemical energy into electrical energy. Galvanic cells are often used in batteries. Michael Faraday defined the cathode of a cell as the electrode to which cations (positively charged ions, like silver ions Ag) flow within the cell, to be reduced by reacting with electrons (negatively charged) from that electrode. Likewise he defined the anode as the electrode to which anions (negatively charged ions, like chloride ions Cl) flow within
Concentration polarization Concentration polarization Concentration polarization is a term used in the scientific fields of electrochemistry and membrane science. In electrochemistry, concentration polarization denotes the part of the polarization of an electrolytic cell resulting from changes in the electrolyte concentration due to the passage of current through the electrode/solution interface. Here "polarization" is understood as the shift of the Electrochemical potential difference across the cell from its equilibrium value. When the term is used in this sense, it is equivalent to “concentration overpotential”. the changes in concentration (emergence of concentration gradients in the solution adjacent to the electrode surface) is the difference