Intro to Addition Reactions - Video Tutorials & Practice Problems

Addition Reactions Concept 1

Now, we can say here that alkenes and all kinds undergo addition reactions. Now, what exactly is an addition reaction? Well, this is the addition of atoms to pi bonds which results in double or triple bonds breaking. So double or triple bond breakage here, we're going to say that pi bonds are broken and new sigma bonds are formed. Here, we're going to say there are three major types of addition reactions and they are halogen nation hydrogenation and hydro halogen. So here we take a look at additional reactions we have here, halogen nation and hydro hydrogenation halogen just means that we're adding halogens to our py bonds. If we take a look here, we have our alkene, we have a carbon here and a carbon here. Remember, carbon must make four bonds. What happens is we break one of these pie bonds and we use that bond to help us attach these two halogens to my, used to be alkene in the process we make what's called a die haid in hydrogenation. We're adding hydrogens to our P bond. So here these two hydrogens get added, we still have these other hydrogens attached. So they're still there we're more focused on what's our new overall compound. So adding hydrogens here through hydrogenation creates what an alkane. Then if we go to hydro halogen nation, we put this a bit different because we're not adding the same two groups to the double bond. Here, we have our alkene and we're using HX. So here we have hydrogen and a halogen. The halogen here is Bromine chlorine. What happens is that we, we have the hydrogen and halogen adding to create an alkyl haid. Later on, we'll learn specific rules to tell us which double bonded carbon gets the hydrogen and which one gets the halogen. But for right now, just realize that hydro halogen nation adds a hydrogen, which is the hydro part and a halogen, which is the halogen part to create inal haid. Now, here we're going to say we have one mole, every agent needed for every pie bond. So if we had a triple bond, we'd need two moles of the reagent, alkene only has one pipe bond. So we only need one mole. Now, remember a double bond is composed of one sigma bond and one pi bond. A triple bond is consistent of one sigma bond and two pi bonds, the sigma bond is always going to be there. It's just the number of pi bonds that are increasing, right? So just remember we have these three types of addition reactions that are pretty common amongst alkene species and alky species

Intro to Addition Reactions Example 1

Which of the following represents an addition reaction. So remember at this point, we're talking about addition reaction in respect to alkenes and alk kinds or adding things to these alkenes and al kinds by sacrificing their P bonds. If we take a look at the first one, we have a pi bond here, but it's not of an alkene or an alky and it's still there at the end. So this would not be our type of addition reaction. Next, we have an alcohol and we're using some type of acid and heat and it actually creates an alkane. Remember addition reactions were getting rid of the py bond to add things to our structure. The answer is C because in C, what do we have? We have an alkene, we're adding hydrochloric acid to it. We see that an H got added here and a coin got added to the other alkane carbon. This represents hydro halogen nation. This would be our type of additional reaction we've covered so far, right. So here, our final answer will be option C

How many moles of reagent are needed for the addition of the following alkyne?

• A. 2 moles
• B. 3 moles
• C. 1 mole
• D. 4 moles