Electrolytic Cell Concept

by Jules Bruno
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Hey everyone before we talk about the other type of electrochemical sound, let's revisit certain variables. So here we're going to say, in terms of spontaneity, the following correlations between the following variables can be made. So here we have gibbs free energy. Under standard conditions, we have our equilibrium constant. K. Our standard cell potential. Here we have our standard entropy and this is entropy of our universe. Now we have reaction quotient versus K. R equilibrium constant. And this will tell us the reaction classification as well as cell type. So here, in the first row, when we have the configuration this way, these are all conditions that lead to a spontaneous reaction. And if we're talking about spontaneous reaction, then the electrochemical cell is a galvanic cell or by its other name of all takes. Now, here, if we were to reverse everything, reverse the sign would expect the opposite result. So this would be a non spontaneous reaction and that be connected to the electrochemical cell. We'll talk about right after this chart, which is your electrolytic cell. And then finally, if everything is equal to certain variables, we're going to say that we are at equilibrium and you'd represent a dead battery. Now, here, when we talk about electrochemical cell, it doesn't function spontaneously. So it requires an outside energy source. So it requires a battery. Now, here we're gonna say, our electrochemical cell or electrolytic electrolytic cell is a non spontaneous electrochemical cell and it consumes electricity. And so requires a battery. Remember a galvanic or voltaic cell is different. It is literally a battery it produces and discharges electricity here. This one needs a power source. So it needs a battery. But here it doesn't matter if it's an electrolytic cell or galvanic cell. Oxidation always occurs at the node reduction always occurs at the cathode. So here we see our electrons moving in this general direction. So they'd be moving towards a cathode that does not change and the electrons are leaving this electrode. So this would have to be our adam. What you should realize here though is that with an electrolytic cell things are not spontaneous or they don't happen naturally. The catholic here is negatively charged negative electrons don't want to go to something that's already negative. Remember life charges repel, we need that outside energy source to force the electrons to go that way and then electrons don't want to leave something that's positive here, the analyst positive. But again, we're using that battery to force the electrons away from our positive a node electrode. Now here, electron affinity would have to be low for the anodes. We don't want the electrons to stay near the anodes ionization here would have to be high for the cathode. We don't want those electrons once they go there to come off. So basically when it comes to an electrolytic cell, it's non spontaneous. A lot of the process. A lot of the way of labeling things are the opposite of a galvanic cell really the place that things hold true is in terms of reduction and oxidation. The cathode is still the site of reduction and the and it is still the site of oxidation. Right? So here, just remember these few key things about electronic cells. Remember the variables up above to help us determine if the reaction is spontaneous, non spontaneous or a dead battery.