Predict the anode, cathode, and overall cell reactions when an aqueous solution of each of the following salts is electrolyzed in a cell having inert electrodes. (c) LiOH

Video transcript

Hello. And this premier asked what are the cathode and showed an overall cell reaction for the electrolysis in a cell with electrodes of an aqueous solution of potassium chloride salt. Let's look at the possible reactions that could occur at the cathode. So we could have potassium mines being reduced form potassium metal. Standard reduction potential. This half reaction is negative 2.92V. Since this isn't an adequate solution, we could also have the hydrogen in water be reduced to form hydrogen gas and two hydroxide. The standard reduction potential for this half reaction is negative 0.83V. By comparing the standard reduction potentials. The one that is the less negative will be the one that has the greatest potential to be reduced. So that will be the reaction. Then that takes place at the cathode and looking at the possible reactions that it could occur at the anodes. We have all right being oxidized to form chlorine dioxide. Standard oxidation potential, which would be the opposite sign of the standard reduction potential is equal to negative 0.95V. And again, given that we have an adequate solution water, the oxygen in the water could be oxidized to form oxygen gas because for hydrogen ions and for electrons, standard oxidation potential Is -1.23V. If you compare the standard oxidation potential, the one that has the less negative standard oxidation potential is the one that is most likely to be oxidized. So that would be the oxidation of the chloride and combining. Then these two half reactions will get the overall reaction. So we see that the number of electrons that are being gained is two. The number of electrons being lost is one. These have to be equal in order for us to combine our two half reactions. Number of electrons lost has two electrons gained. So we'll multiply the reaction taking place at the an ode by two. In doing so. Then our number of electrons being lost and gained are the same. So those will cancel finding what's left. Then halves two waters reacting with 248 irons form hydrogen gas and two moles of chlorine dioxide gas plus two hydroxide ions. So this is our overall reaction based on the reaction is taking place at the animal and the catheter. Thanks for watching. Hope this out.