In this lesson, we'll be looking at addition reactions that falls under organic chemistry. Now, to add, addition means to add. And I've spoken about this in my video that goes over the difference between addition, elimination, and substitution reactions. Addition is to add something. So, we are typically going from something that has double bonds. It has space to be added to to something with single bonds. So, once I add, it creates something with single bonds. So if we take a look for example at this compound, this is but 1in. It's a double bond compound. It's an alken and I'm adding hydrogen to it. And as you know hydrogen is HH. And how addition works is the double bond is broken. So it goes from something that is unsaturated. We take the double bond away. This compound over here is now the product. This is my product. I have broken the double bond. In place of the double bond, I have a single bond. And now I have space over here. space to add different atoms because every carbon must have four bonds. So I can add a hydrogen over here and a hydrogen over here. So I've performed an addition reaction. Now you get different types of addition reactions. They each have their own names. And the way we name the different addition reactions depends on what we're adding to the compound. So this one is called hydrogenation. Hydrogenation. We're adding two hydrogen atoms. We're adding hydrogen. That is addition. So essentially addition is when we take compounds with a double bond. So alkenes and we form compounds with single bonds. Now in the example I did we formed an alkan but you can also form alcohols and halo alkanes because they also have single bonds. We'll be focusing on these four types of addition reactions. And as I said the name basically tells you what you are adding. So if you see hydro halogenation, we spoke about hydrogenation as being adding a H2. You're adding a H and a H, an H2, a hydrogen. Hydro halogenation. So hydro again is adding the H. Halogen is adding an X. Now remember a halogen can be chlorine, bromine, iodine, florine, whatever it is. So for example, adding HCl or adding hydrogen broomemide or hydrogen fluoride or hydrogen iodide. Any one of those. Then halogenation is adding an XX. In other words, adding chlorine, Cl2, bromine, Br2, iodine, florine. We know that these are all diatomic molecules. So adding two of them, hyogenation and then hydration. To hydrate yourself, take water in, drink water. So hydration is adding H2O. And each of these reactions have what we call different reaction conditions. And what is a reaction condition? Basically, it's just criteria that need to be met, things that need to happen in order for this particular reaction to happen. You need to study the reaction conditions. You need to learn them off by heart. They can be used to identify what reaction we are talking about. So, for example, if I give you a reaction and I say we go from A to B and I tell you that it's an addition reaction and I tell you that the catalyst is platinum. That's the only information I give you. You must know, okay, platinum is my catalyst. That means that I'm talking about hydrogenation. I'm adding hydrogen H. So we already did speak about the first type of addition reaction hydrogenation and we did an example of hydrogenation. So that is adding H2 or HH to an alken. This was our example. We went from but one in to butane. As you can see we're going from double bonds to single bonds. We are adding. Halogenation is the addition of a hogen molecule. we say XX but that can represent something like Br and so on and obviously because we're adding a H hallogen to an alken we are going to form a hello alkan as the product here are the reaction conditions the reaction happens easily at room temperature we don't need water no heat needed for example adding chlorine Cl2 to hex 1 now as you can see if I break the double bond over here I add in all the hydrogens that originally present. We can now see that there's space on this carbon to add something. So, we're going to put one of our Cl's over here and there's space to add something over here. So, we can put another Cl over there. Now, obviously, because it's Cl2, they're both chlorine atoms. It's the same thing no matter where you put which Clom. And as you can see, we are going from an alken with double bonds to a hello alkan with single bonds. So, addition will always be double to single bonds. And this compound's name is 1 comma 2 di two chloros dchloro hexane. There we go. Our next type of addition reaction is hydro-halogenation. And remember the hydro is a hydrogen. Halogenation a halogen. And again a halo alkan forms as a product. This time we're not adding two halogens. We're just adding one halogen. And the other thing we're adding is a hydrogen atom. Reaction conditions no water must be present. But now we need to apply Movnikov's rule. This is Makovnikov's rule and you don't need to know how to state the rule but you need to understand what it means. We can when we go through hydrohalogenation either form what we call a major product or we can form a minor product. I have a whole video on major versus minor products where I go over makovnikov's rule and another rule that applies to elimination. So please go check out that video if you want more details. But basically we form the major product most of the time and when we apply marovnikov's rule it will give us the major product and marovnikov rule says the following. I'll show you with an example relating to hydrohalogenation. If we have the reaction of but one in which is this compound over here with hydrogen broomemide HBr we can form one of two different products one being the major the other being the minor. The reason why is because when we form H when when HBr reacts with butane the hydrogen can either go here or it can go here. And same thing with the bromine it can either go on carbon one or on carbon 2. And which carbon you put it on depends on whether or not we are forming the major or the minor product. So if I ask you for the major product, it means that we must follow Marovnikov's rule, which says that the hydrogen atom is placed on the carbon atom that already has the most hydrogen atoms. So if we take a look at this compound, we are going to form something with single bonds like that. Let's write in the hydrogen's that are already present on the original compound like that. We've broken the double bond, created a single bond, and now Marovnikov's rule says we add the hydrogen to the carbon that already has the most hydrogens. So carbon number one has two hydrogens. Carbon number two only has one hydrogen. So we're going to add the hydrogen to carbon number one because it has the most hydrogens's already. And that means that we must add the bromine over here. This is following Marovnikov's rule and that gives me the major product. If I don't follow Marovnikov's rule, then these two will swap places and we will form the minor product. Again, if you want more information or a slower explanation about major versus minor, go watch this video. I'll link it down below. But that is an example of hydrohalogenation. And as you can see, we're going from alken to hello. Our last addition reaction is called hydration. Think about to be hydrated, you need water. So it's adding water to an alken. And we're going to add water in the following way. We're going to add O to one of our carbons and H hydrogen to the other carbon. Together it gives me H2O. And because we're adding O, we are forming alcohol as a product. Here are your reaction conditions. You need to study this off by heart. We need a strong acid catalyst like sulfuric acid or phosphoric acid and water must be in excess. And again we need to follow marovnikov's rule to give us the major product. So for example we have the reaction between but1in which looks like this and water as you know water is obviously H2O but in its structural formula I can write it like that. Remember what I told you on one of these carbons we are going to place the O which is going to turn it into an alcohol. On the other carbon we will place the hydrogen. Now, Marovnikov's rule says to form the major product, we add the hydrogen. So, this to the carbon that already has the most hydrogens. This carbon has two hydrogens. This carbon has one hydrogen. So, we are going to add the hydrogen atom to the carbon atom that already has the most. So, this is what the product would look like when I break the bond. And then we add the hydrogen to this carbon and the O to this carbon. This would be the major product. The minor product, you would simply swap these two around. Now what is the name of the major product? It would be butan 2. Butan 2. It's a alcohol now. There's the O. And that is a summary of all your addition reactions. I hope to see you in the next video where we cover elimination and then eventually substitution reactions. Bye everyone.