 Okay, wait, I'll just tell you what I did. See, what I just said, that we have discussed so far the three different steps, okay, Ores concentration and then conversion of concentrated ore into oxides and then reduction, okay. Last method we have, the purification of these metals, right, because the metal that we get is not pure. So we'll, for purification, the method that we use here is electro-refining, okay. So electro-refining is a technique that we use and it is used for the purification of copper, zinc, there are many different metals we use for this purpose, right. Right on this method, this method is used for the purification of, purification of copper zinc, tin, silver, gold, nickel, lead and aluminium. For all these, you know, metals we use electro-refining process. Like I said, it is based on the concept of electrochemistry. So obviously we have an electro-cathode and an anode here, right. So we use cathode for this purpose, the cathode metal is made up of, made up of thin strip of impure metal. Now one thing you take care of here, we'll take cathode as an impure metal, impure metal of what the metal to which is to be refined, right. Because the metal which we have to refine, we'll take the impure metal of that as a cathode, right. Anode we use here, it is a large slab, large slab of impure metal, impure metal. Again we use the same metal which is to be refined. So basically cathode and anode, both we have same metal, impure metal we have here, right. Cathode is a thin strip and anode is a large slab comparatively, right. The electrolyte because obviously the process is related to the electro-refining. So we also use some electrolyte in this process. So electrolyte is what, it is the aqua solution of, aqua solution of suitable salt of the same metal, of the same metal. So you see here, draw this, this is the arrangement we have, electrolyte is this. This is the large slab here, it's pure metal only. What I said, these two cathode and anode made up of the metal that we have here, which is to be refined. Oh you are saying it is a pure metal that we use here, just a second, you copy it down, I'll tell you. Oh yeah, it's pure, I have written it wrong by mistake, it's pure, correct. That's what you were saying, right, it's pure, yeah it's correct, yeah, yeah, right, right, correct, by mistake, okay. So cathode is made up of pure metal, which is to be refined, okay, yeah, in that case both will be same, if it is also impure, impure both, yeah fine thing, right. So cathode is made up of pure metal, thin strip, right, this is the large slab. So this one is, this one is cathode, thin strip, pure metal, anode is large slab, right, and it is impure metal, okay. This is the overall process we have, we obviously connect this, right, the arrangement we have, total arrangement here. So reaction at cathode is what, if I write down the reaction we all know, suppose the metal is M we have, so at cathode reduction takes place, I'll write down the general expression here, Mn plus plus N electron gives M, right, and at anode the reaction will be, I'll write down this side, first of all you copy down this, I'll go to the next page, yeah. So the reaction of anode, here the anode we have two reactions takes place, the first reaction at anode, obviously the oxidation of metal M to Mn plus, sorry, M to Mn plus plus N electron, and the second reaction is the impurities, Xn plus half of X2 plus N electrons, oh just a second, it should be like this, half of X2 and this, half of X2 gives Xn plus plus electron, this is the impurity, so this reaction is, we don't want this reaction to take place, this is unwanted reaction, and this one is wanted reaction, we want this reaction to take place because metal we need to get, this is unwanted reaction, okay. So here what happens, the anionic part of the electrolyte, this is the anionic part of the electrolyte, the anionic part of the electrolyte is to be chosen, I think there is again, I'll write it down first, anionic part of the electrolyte is to be chosen as in such a way, in such a way that anodic reaction, that anodic reaction 2 does not take place, so this is reaction 1 and this is reaction 2, we won't, we won't, we don't want this reaction to take place, and hence will take any part in such a way that this reaction won't take place, and for that if you remember, we have discussed this, the over potential concept in electrochemistry, right, so depending on those values, over potential, electrode potential and all, we'll choose the anionic part, I made a mistake again here, I'm sorry, this should be, let me write down this anionic part, no, so it should be xn minus, it is xn minus and half of x2, now it's fine, charges, balance, oxidation also takes place, okay, n minus 2 half x, that's why it's anionic part, okay, so what happens here, this second reaction does not take place, that's what our concern is, so we'll choose this anionic part in such a way that by any means, whether it is over potential or electrode potential, because we know the metal, the one which has more oxidation potential, sorry, more reduction potential will get reduced, if you remember, the two metal if you have, the more, the one which has more reduction potential will get reduced, the one which has low reduction potential, which get oxidized, the one which has more oxidation potential will get oxidized, the one which has low oxidation potential will get reduced, if you remember this, we have discussed this in electrochemistry that whatever more, whether it is reduction potential or oxidation potential, whatever more is there, that will take place for that particular metal, right, so this reaction is unwanted, so anionic part since it is getting oxidized, so oxidation potential of anionic part must be lesser than the oxidation potential of this metal, that is the conclusion here we have, so the oxidation potential of the anionic part of electrolyte must be less than the oxidation potential of metal, is it clear, understood this, is clear, done all of you tell me, okay, now one thing you see at anode, this oxidation takes place and anode is made up of impure metal if you see, right, so from impure metal, this is anode reaction, so impure metal converts into Mn plus, okay, and Mn plus get reduced cathode, so cathode is made up of pure metal, right, so from the impure metal anode, the metal ion is coming into the solution and which is getting deposited onto the cathode, that's how we get the pure metal in this, got it, right, so the anode which is impure, see the diagram you see in the last page, anode it is impure, so from this anode, first reaction takes place, we'll get Mn plus the metal ion and this metal ion get oxidized at cathode, so reduced at cathode and converts into M solid, that's how we get pure metal in this process, okay, condition is what, whatever electrolyte will choose, the anionic part, the oxidation potential of anionic part must be lesser than the oxidation potential of the metal, right, so if you, if you think this reverse, what happens if the oxidation potential of metal is lesser than the oxidation potential of the anionic part of the electrolyte, okay, so write down this point, if the oxidation potential, if the oxidation potential of the metallic impurities is low, sorry, of the metallic impurities is lower than the oxidation potential of metallic impurities is lower than the oxidation potential of the anionic part of the electrolyte is lower than the anionic part of the electrolyte, then the metal gets separated in the form of anode mud, metal gets separated in the form of anode mud, this anode mud also they ask sometimes, you'll see this question in the book, okay, anode mud, what is anode mud, it is the, it is the metal which gets separated in the form of, it is basically a slag, okay, in the form of a slag or impurities, when the oxidation potential of metal is lower than the oxidation potential of anionic part of the electrolyte, got it, did you get it, done all of you, okay, yeah, so this is the extraction process we have, we have discussed all the four methods, steps which involves for the extraction of various different metals, okay, now we'll have all these metals like silver, copper, iron and how do we extract these metals by using the different, different processes that we'll see one by one, okay, but before going into that, I'll just want to discuss first the Ellingham diagram, okay, Ellingham diagram, you know, have you done it, Ellingham diagram?