6.24 Name the processes from which chlorine is obtained as a by-product. What will happen if an aqueous solution of NaCl is subjected to electrolysis?

In the electrolysis of molten NaCl, $C{L}_{2}$ is obtained at the anode as a by product.
If an aqueous solution of NaCl is electrolyzed, $C{l}_{2}$ will be obtained at the anode but at the cathode, ${H}_{2}$ will be obtained (instead of Na). This is because the standard reduction potential of Na (E°= − 2.71 V) is more negative than that of ${H}_{2}O$ (E° = − 0.83 V). Hence, ${H}_{2}O$ will get preference to get reduced at the cathode and as a result, ${H}_{2}$ is evolved.