 Today I'd like to talk to you about oxidation reduction reactions. These reactions involve either loss or gain in fact both, loss and gain of electrons in the chemical. The oxidation reaction reduction reaction is important. It provides us with with energy for our bodies to operate on. It's that that's one thing. It also provides us with energy for batteries and and it's it's the basis for electricity and it also is a very important reaction for us because it is the reaction which causes iron to rust and that reaction is illustrated here and you will know that in this reaction that we have we have several different things that are taking place that we'll talk about. The most important thing to remember about an oxidation reduction reaction is that both of these have to take place at this at essentially the same time. If you have loss of electrons you also have to have them being gained by another species. When we look at a reaction like zinc plus copper chloride giving us zinc chloride plus copper there are actually two separate things occurring in this process. The first thing is that zinc is going from an oxidation state of zero which is its natural state to zinc plus two. One of the things that we need to remember when we write these reactions this is called a half reaction because it illustrates half of the process and the reactions have to be balanced electrically. In other words the charge has to be the same on both sides of the reaction. We have a zero charge on the left-hand side. We have a positive two charge on the next side. That tells us that we will need to have two negative charges to balance that and since we know that our electrons have a negative charge that means that zinc zero going to zinc plus two is losing two electrons. They're on the product side here. So zinc zero gives zinc plus two plus two electrons. Conversely our copper is plus two on this the left-hand side. Copper is going to copper zero and so the question would be where will the electrons go in this reaction? Well think about it you have no charge here positive two here. The electrons are going to go on the more positive side. We need two electrons to be added here in order to get the charge balance. So we add our electrons to the reactants. So these are examples of half reactions that we can look at. When we look at these two processes we have oxidation and reduction. Oxidation and reduction. Oxidation is the loss of electrons. Reduction is the gain of electrons. You can remember this easy enough by saying Leo goes Ger. Leo the lion. Loss of electrons oxidation. Gain of electrons reduction. Okay oxidation reduction. So when we look at the previous example zinc giving zinc plus two plus two electrons. This zinc is losing two electrons so that would be loss of electrons. This is oxidation. Copper plus two and two electrons gives copper zero. In this instance the copper plus two is gaining electrons. This is reduction. Now oxidation reduction reactions can be very slow. They can occur very quickly. And one of the reactions which a lot of people don't really think about as being an oxidation reduction reaction is combustion. And if you take carbon and oxygen and react them, carbon is going from carbon zero to carbon plus four. Oxygen is going from zero to minus two. When we do this reaction we have a lot of heat and energy that are that are given off by the reaction. And but we do have electrons being gained and lost. We're going from carbons going from zero to plus four meaning it's losing electrons. Oxygen is going from zero to negative two meaning it's gaining electrons. So the carbon side of the reaction is oxidation. The oxygen side will be reduction. There's another form of this that is that is called spontaneous combustion. Spontaneous combustion can do the same sort of things that you have here. But it occurs at a much much slower rate. And it but it's an equally important reaction depending on where you are. Oxidation reduction reactions are important in chemistry. They're important in life. As we move forward into the further regions of this century we'll find that we're going to be using these reactions a whole lot more in order to obtain energy and other things. Thank you.