Magnesium, the element, is produced commercially by electrolysis from a molten salt (the 'electrolyte') using a cell similar to the one shown here. (c) Recall that in an electrolytic cell the anode is given the + sign and the cathode is given the – sign, which is the opposite of what we see in batteries. What half-reaction occurs at the anode in this electrolytic cell?

Video transcript

Welcome back everyone. The cell shown in the image below is used to commercially produce strong team the element via electrolysis from a molten salt such as strontium to chloride. Remember that in an electrolytic cell which is the opposite of what we see in batteries. The anNA has given the negative sign and the cathode is given the positive sign. What is the half reaction at the anodes of the electrolytic cell? So what we're going to first begin with is writing out writing out our overall reaction which is our strong team to chloride, which undergoes electrolysis and produces our strontium county on As well as our two moles of our chloride an ion. So this is a salt. So this gets the solid phase as a label here. According to our prompt. Now from this overall reaction, we want to write out our half reactions and we can also use the image to help us write out our half reactions. So based on our image, our image is telling us that chlorine gas is being produced as a product. So it's what we will be beginning with here where we have our chloride an ion which gains an electron to form that chlorine gas. For our second half reaction, we take our chloride an ion, we're sorry our strontium catalon where we show that it will gain those two electrons back to form our liquid strontium. Now, according to the prompt, we need to figure out which of these half reactions would be hour and half reaction. So we want to recall that when we have electrons on the product side of our half reaction being that we have a release of electrons. This means that we have where the reaction occurs as an oxidation, which then tells us that this is our an ode half reaction. We want to recognize that because we have electrons on the reactant side here, that this reaction occurs as a reduction, which will occur at the cathode of our voltaic cell or rather electrolytic cell here. So, because we need to give the note half reaction, our final answer is going to be this first half reaction here where we see our electrons on the product side. So what's highlighted in yellow is our final answer for our an ode half reaction for our electrolytic cell. If you have any questions, please leave them down below and I'll see everyone in the next practice video.