 Okay, so let's try to predict this electrolysis product of a molten salt mixture Okay, so that molten helps us out to remember that it's in the liquid state So we have a naturally occurring mixture of sodium bromide and magnesium chloride So let's go ahead and write that down Okay, and it decomposes into an electrolytic cell Predict the substance formed at each electrode and write the balanced half-reactions and the overall cell reaction Okay, so the possible oxidizing species, let's write that up So are going to be Sodium plus and Magnesium Okay, so the two-cab so The possible reducing species be the two anion So how do we know which one gets Reduced how do we know which one gets oxidized? Well, we have to remember our periodic trends about first ionization energy and Electromegativity, okay So if we remember our trend about first ionization energy What we should know is that magnesium has a higher first ionization energy than sodium Okay, so since that's the case it means it's harder to remove an electron from magnesium Than it is for sodium Okay, so it's since that's the case it should follow that magnesium would be easier to donate an electron to then sodium okay, so Since that's the case the thing that gets reduced is the magnesium ion Okay, so we're going to write a half reaction With that magnesium Okay, so we've got this now remember this is in a molten salt mixture. Okay, so this is to remind myself so mg2 plus liquid This is getting reduced by two electrons And it's going to magnesium metal in the liquid form Everybody okay with the logic process there? So now let's look at the possible reducing species in this case. We have to look at the electronegativity Chlorine is more electronegative than bromine So that means that chlorine must be holding on to its electrons more tightly than bromine Okay, since that's the case that means that the backwards logic means that Bromine must be able to give up an electron easier than chlorine. Is everybody okay with that logic process? So since that's the case we would assume or think That or no, we don't assume anything Right that bromine must be the one giving up its electrons or Oxidizing the magnesium is everybody okay with that So in this case it's going to be Br-liquid again. Why is it in the molten state? That goes to well Br2 and that's going to be a gas Okay, so we come off as a gas But notice we've got two VR's there. So we have that two VR's over here And with two minuses that means We've got two electrons there So this Electrons are equivalent here. So we can cancel them out Write the overall reaction that we're going to be having in this electrolytic cell so mg2 plus liquid Plus two VR minus liquid goes to mg liquid Plus VR to gas So that's the overall cell reaction, okay, and it didn't say what happens at each electrode so Reduction at the cathode Oxidation at the end, okay Any questions on this one Question yes, because it's so hot in that molten mixture That bromine is not in its liquid state anymore. Okay, so it's a good question. Okay, I Understand that normally it's a liquid in its standard state Any other question