 So, in electric cells energy is used to force electrons in the opposite direction that they would normally go, so in the non-spontaneous redox direction, the electrons going in the opposite direction. What it means is that things would normally oxidize, ions had reduced and things that are normally reduced would then oxidize. So we're forcing the electrons in the opposite direction. We can use electrolysis for a few things, we can use it to plate metals onto other metals, or metals onto anything that conducts electricity. We can make active metals from their ions, and we can also make gases from liquids, for example. You can use electrolysis to break up water into hydrogen and oxygen, and that tells us where the name comes from. So, electro for electricity, lysic, lysis is breaking, so breaking using electricity. So here's an example of electrolytic cell. So we've got a copper sulfate solution down the bottom here, two copper electrodes, and we've got a source of electrons being forced in the other way, so this is a battery up here. So we're forcing the electrons in this direction over here, so we're forcing them over to this electrode, and at that electrode we're getting copper ions from the solution plating onto the copper electrode that's in the solution. So because we've got the ions being reduced to copper, so the copper ions are being reduced to copper, that's happening at the cathode, so cathode is where reduction happens. And because we're pushing the electrons over here, we've got a lot of electrons on this electrode, that's giving it a negative charge. If we have a look at what's happening at the other electrode, so this is going to be the anode, copper from the rod is being oxidized to copper ions. So the copper is being oxidized to copper ions there, sitting in solution, and then some of those copper ions will be reduced onto the copper rod. You could use this to plate something in copper, so rather than having a copper rod in here, you could have a graphite sheet, a graphite rod. You could have another metal, so you could have a key, and you could code that key in copper for example. Here's another example, so here we have making sodium. So here you have a molten sodium mix, so this is just sold as being heated up. It has to be molten, not a solution, because the solution won't work. You'd reduce water rather than the sodium. So at the cathode again, we're getting a reduction. The sodium ions from the melts are being reduced to liquid sodium. The liquid sodium would go up in this case because it's less dense than the salt, so you could collect it at the top over here. And the chloride ions over here would be oxidized, so their oxidation is lost. The chloride ions lose their electrons and you make chlorine gas. So chlorine gas would be bubbling up over here. So this is how you make active metals from their salt. So you can use this to make sodium, potassium, lithium, and so on. Some things to remember from those diagrams we saw. In electrolytic cell, the anode is always the side of oxidation, and the cathode is always the side of reduction. That's the same for electrolytic or galvanic cells. What changes though is the science. So because we're forcing electrons in the opposite direction, what would normally be anode negative oxidation if a galvanic cell becomes anode positive oxidation. And over the other side, what would normally be cathode positive reduction becomes cathode negative reduction. So you can still use your mnemonics from the galvanics to help you remember, but you just have to remember that the charge changes over. So in an electrolytic cell, the charge is reversed compared to the galvanic cell.