Correlation between EMF and Gibbs Free Energy, and the Relative Concentration of Electrolytes in a Concentration Cell

The experiment aimed at establishing a link between the varying concentration of the electrolyte in one half-cell of a concentration cell and the resulting EMF generated across the cell. Further, it also drew a connection between this variation and the change in Gibbs free energy for the electrochemical reaction. The change in Gibbs free energy calculated for the electrochemical reaction for each C2 value indicated a decreasing trend with an increasing C2 concentration. It was thus observed that as C2 increased, or the difference in concentrations of the two electrolytes decreased, the spontaneity of the reaction decreased. Reduction occurs at the negatively charged cathode and oxidation occurs at the positively charged anode. Here, aqueous NaCl is undergoing electrolysis – where the Cl-1 ions are attracted to the positive anode and get oxidized due to the loss of electrons and emerge as chlorine Cl2 gas.