 So let's talk about displacement reactions. So if you put a more active metal in a solution of a less active metal's ions, you get a displacement reaction occurring. The more active metal that you put in oxidizes, and that oxidizes to ions of that metal, and the less active metal's ions are reduced to that solid metal. So let's have a look at the example. So down here I have, this is a strip of zinc that we had to clean, and we're putting it in a copper solution. And this is sped up. As soon as the copper solutions, this is copper sulfate, as soon as it's added we can see that the zinc turns dark, and that darkness over time you'll see it changes to a red color. Also as the reaction is going on, have a look at the color of the blue of the solution and see if that changes. So let's have a look at what's happening here. So zinc is a more active metal than copper, so they've got copper ions in the solution, so the zinc is being oxidized. So again, zinc is being oxidized to zinc ions, so zinc makes a 2-plus ion, and we're getting 2 electrons. So oxidation is lost, it's losing the electrons. The copper ions in the copper sulfate solution here are being reduced. So we take the copper ions in that pretty blue CuSO4, SO4 is 2 minus, so it's the Cu2-plus ion. It's a really pretty blue one. So the copper 2 ion, that's gaining 2 electrons, and we're producing solid copper. And that's what this brown color that you're seeing is. That darkness of the metal and now the brown that's coming out, that's from the copper. So copper metal is brown. So as time is going on, we can see that the copper color, the blue copper of the solution is getting lighter and lighter, and we'll compare it at the end of the video to what it was at the start. So overall we've got 2 electrons on either side of the arrow, so we don't have to do any balancing there. So we've got zinc plus copper ions is going to zinc ions plus copper, and we can put our states in. So we're getting solid copper from the copper ions that are being reduced, and we can see the brown color really nicely now. The zinc ions are going into solution, so that's aqueous, copper ions from the copper sulfate that were dissolved in water, so that's aqueous, and our zinc was a solid metal when reported in there. So now if we have a look at the video, I'll pause the video there at the end. We rewind it to the start, and we can see that if we have a look at the blue color, fairly dark, lighter, lighter, lighter. And the reason why it's getting lighter as time is going on is those copper ions from the solution that give the solution the blue color are being reduced to solid copper, so the solution changes color. So another example is copper being put in silver nitrate solution, and we can see it down here. So we put some copper wire, which is the brown, and we put that into a color solution of silver nitrate. So there's a liquid in here. And we can see as the reaction progresses, we get these crystals of silver forming on the copper wire. So let's have a look at what the reaction is. We'll also see a color change over time of the solution, so keep an eye out for that. So we need to have something being oxidized to generate electrons. In this case, it's the copper wire here. The solid copper is being oxidized to copper ions. So we'll go copper goes to copper, we'll call it 2 plus ions, plus 2 electrons. So the copper metal here is being oxidized, and that's producing electrons. So those electrons are able to reduce the silver ions in the solution. So the silver ions, Ag plus, plus an electron, is being reduced to solid silver. Now if we have a look, we've got two electrons at the top and only one down the bottom, so we need to multiply the bottom one by two. So we get copper plus 2 silver ions, 1 plus, plus 2 electrons goes to copper 2 plus, plus 2 electrons, plus 2 silvers. The electrons will cancel out. So we're left with the overall equation of copper plus 2 silver ions goes to copper ions, Cu2 plus ions, plus 2 solid silver. And we're going to put out states in, so solid for that one, aqueous for the ions, they're dissolved in solution, and solid there. So now if you have a look over here, you can start to see a bit of blue forming in the color solution. That blue, that's the blue copper 2 plus ions that are going into the solution. So as the copper is oxidized, the silver ions are reduced. So the copper ions are going into solution, that gives it that faint blue color. So here we have a more active metal, in this case copper, being placed in a solution of a less active metal's ions, in this case silver, and we're getting displacement.