 So good morning. Happy second to last Friday of the term, right? So I just have a couple of announcements to make if you don't mind ladies. Thank you so quiz five, I know it says on the Schedule that quiz five is today It's not today. It's going to be next week. Okay, so we'll do it next week Next Wednesday for you online people it'll probably be from Wednesday to Friday that you'll be able to take it Okay, so it'll be opening up on Wednesday I also want to mention of course the final is The Wednesday after next Wednesday. Okay, if you're going to take the final with me in class So what I think I'm going to do is I nas I'm going to get I nas to help me out with the final Do you have time during that time? Okay, so okay, so and I'll split you guys up into two rooms and we'll do it on basis of last name Okay, so you'll know prior to The exam where you're to take it. Okay that way we can spread out, you know I mean I'm expecting more people for this exam than I have been for the other exam So I want to make sure Everybody has ample opportunity to feel comfortable. Okay, so I'll be sending you out an email about that once I Learn what room I'm able to Also use okay, so half of you will be in this room and half of you will be in another room probably one of the rooms like down on the other end in this the Newer part of the building like 119 or something like that Just wait for the email and I'll send it to you Remember four by six cards You can use a four by six card for the final But it can only be written in your handwriting in order for me to be able to Go over all of the four by six cards to make sure everybody did it the right way and Be able to distribute them to the various places where people are going to be taking the test the testing center or to me or Inaz I'm going to need to see them Prior to the exam obviously So what I'll have you do is turn them in the that Friday So our ten twelve ten which is a week from today Okay, so if I don't have it by that day Then you won't be able to use a four by six card on the final So don't show up with a four by six card expecting that you'll be able to use it Okay, what'll happen is I'll sit you guys all down and then I'll just call out your names and redistribute your four by six Cards, okay, or if you go to the testing center obviously the when you walk in they'll give you your four by six card when You're about to take your test if there's something wrong with your four by six card Okay, I'm not going to send everybody an individual email explaining as to why Therefore by six card doesn't work. Just follow the rules and you'll be able to do it Okay, you'll be able to use it if your four by six card is not the way that I've prescribed it Okay, you won't be able to use it. So you'll just come into the final and you'll be like I don't have a four by six card. Okay, so make sure That you do it the proper way, okay Let's see Lab final remember there's a lab final. Okay, so you're going to need one of those Blue scantrons. Okay, so not this kind of scantrons, but the other kind of scantrons I think you can get them in next to subway in the Yeah, yeah, so Molly Molly to okay Yeah, well Try to make it the blue one. Okay. I think they only cost like 70 cents or something that thing. Yeah The gray one or whatever it's called Huh? Yes, the front and the backs here. Can I see that Jane? Do you mind? Okay? This is the Uh Scantron that I was referring to okay. Yeah, I don't know what he's doing with the whole thing He'll probably be using a similar exam to us to the What number? the Accu-Scan number two eight Two eight zero four zero Okay So are there any questions about any of this stuff remember if you're on the on the online class you have to email me prior to me Allowing you to take the test with us in class. Okay? Okay, so I think that's everything for announcements. Um, I think we Well, I think we finished this slide last time But if you recall we were talking about alkanes and alkanes are the simplest form of hydrocarbons They only have sigma bonds in them. No pi bonds. No other functional groups. No hetero atoms. Okay? Here are a variety of structures of Hydrocarbons remember this is the known as a unbranched hydrocarbon here. This is a branch to branch This is a cyclical or cyclic Alcane right a cycloalkane. This is also a cycloalkane Remember you're going to have to know the first ten alkanes the names of the first ten alkanes, but You remember hopefully that Little phrase that I gave you to remember the first four right my seat peanut butter Yeah, so methyl ethyl propyl butyl and all the rest are like we were saying just the Latin names of the numbers pentane hexane Heptane octane non-ane and decking. Okay? It's good to know those because a lot of times There'll be Groups that are coming off But yours yeah Come coming off of Different molecule right like What's for example just draw a particular molecule? We'll just draw a cyclohexane With one of these groups coming off. So if we look right this is a cyclohexane, but it's got a one two Three carbon chain coming off of it does everybody see that there's three carbons So what we would say is that's a propyl group. Okay a propyl group Propyl group like that And if there was four carbons on it, we call it a butyl group. Okay? There were five carbons. We call it a pentyl group. Okay? There were six we call it a hexal Okay Just this this part is what we're talking about Okay, with three carbons. It was a propyl now that we've changed it to four carbons. It's a Beutel and remember this Beutel is referring to just the regular alkane of four carbons Which is butane? notice the end here this tells you what type of Molecule it is. Okay, so if you ever see something that says aing like that you you you can usually Guess that it'll be an alkane Alkenes a lot of times will end in in okay Alkines will end in iron. Okay, and this suffix ill like here ill Means that it's sticking on something else. Okay? Okay, so hopefully everybody's cool with that list If not study it up and here you go. This is what I was referring to right? So this is methane here ch4 But if we got a ch3 group sticking off of a molecule we call it a methyl group. Okay? Ethane here is this two carbon chain If we got a two carbon chain sticking off a molecule we call it an ethyl group. Okay? So I think this was the last slide we really kind of touched on last time was the correlation between number of carbons in Your carbon chain of your alkane And relating that to the boiling point of the alkane. Okay, so if we look here On the x-axis down here. We have number of carbons that increases incrementally by one Okay, and notice the boiling point is here on the y-axis so if we have Carbon chain of one which is methane right ch4 We notice it's boiling point is somewhere around negative 180 degrees Celsius Okay, when we increase that carbon chain to two or ethane it increases the boiling point Okay, to about negative 100 then three increases it again four increases it again five increases it again Six increases it again. This is the general trend. Okay the higher Number of carbons in your chain or in other words the higher molecular weight of your alkane The higher the boiling point is okay So it's just like my analogy that I always use with the tennis ball and the bowling ball, right? So the heavier of those two items is Harder to break away and to go into the gas phase or throw it up in the air if you will Okay, so if you have lighter things they're easier to break away and go into the gas phase just because they don't need as Much energy to do it So and again notice here All right once you get to a certain number five as a matter of fact pentane Room temperature is this dashed line So at room temperature pentane is a liquid right and in fact all of the hydrocarbons above that Number five are going to be liquid until you get up to the way high numbers and those will be solids, okay? So we've talked about different types of isomers in relation to Like alkenes where we talked about this and trans geometric isomers We've also talked about structural isomers where two molecules have the same structure Or sorry same molecular formula but different structures We call those structural isomers We're going to now talk about another type of isomer called conformational isomers So you're going to be asked to identify whether probably compare or identify whether this is a geometric isomer conformational isomer or Structural isomer, okay, so This molecule that we have up here. This is butane Notice it's one two three four carbons in the carbon chain Hopefully everybody sees that and it's a saturated hydrocarbon Okay, so the only saturated hydrocarbon that has four carbons in its chain is butane, okay? So if we look here, hopefully you see this model that I've created is the same Structure as what's indicated on the left hand box there, okay? So notice I have four carbons in my chain there. Does everybody see I have four carbons in my chain Okay, so if you look at that and relation to this so the only difference between This and that up there is they're showing it to us kind of at this angle like that, okay So you guys see that how it's in relation to what we're showing here Notice both of the methyl groups here and here right both the CH groups the methyl groups are Pointing up in this drawing up here. Okay Notice here. This is the same molecule, okay? This is also butane, right if we look at the carbon chain one two three four, right? There's four carbons in that carbon chain and All of those carbons are saturated with hydrogen, okay? So it's a saturated hydrocarbon with four carbons clearly the only structure that that can Be is butane The only difference between these structures is Notice this methyl groups over here to the right, okay? So let's Build this model to make it look like that second structure So all I have to do is take it and turn it like that, okay? Hopefully everybody can see that the structure on the right is this same Structure that we're showing right here So what have I done to this molecule? Well, it's the same molecule All I've done is rotated it around one of its sigma bonds, okay? So conformational isomers are the same thing. They're just in different Confirmation, okay, if you know what a confirmation is it's like a different way of You know moving or putting your you know parts, okay? so like in other words a Confirmation olisomer of me, right like standing like this would be me standing like this or me standing like this Okay, or me standing like this, okay? So Confirmation olisomers of butane Would be like this Like this like this like this like this like this they're all the same molecule They're just rotating differently in space, okay So in fact what you find why do we care, right? because These molecules would rather be in What would be the most favorable confirmation like the little? Charlie Brown Looking bond line structures. Why is that? Because when they're in what we would might might think of as like the cis structure as opposed to the trans structure if you Want to go there These things these two methyl groups can bump into each other here, okay? So they don't like to bump into each other So what they prefer to do is be arranged in this sort of fashion, which is why we draw everything Like this, okay, because that's this sort of Arrangement, okay? So if we looked at these two things They're the same molecule the only thing we've done is Taken this and rotated it like that, okay? So same molecule Right taking this rotated it like that Cool And there you go. You can see the pictures of the two models. We just built, okay? And how they are arranged differently in space Okay, cycloalkanes. I know we talked about them a briefly already But again, hopefully you can tell That if we draw this little triangle here it correlates to this structure here CH2CH2CH2 all connected by sigma bonds We draw a little box that means we're drawing this structure here Notice the names of these molecules This is called cyclopropane Why do you think it's called cyclopropane? Because there's three carbon atoms, right? So that's where that name comes from cyclopropane, cyclobutane, cyclopentane, and cyclohexane So this is a very very common structure. You'll see cyclohexane So I'd get somewhat familiar with it. Just if you see that kind of hexagon Just know that it's going to be cyclohexane So, let's talk about Some geometric isomers. So remember geometric isomers were like the cis trans isomers So do you remember with the cis trans isomers the reason why those molecules were isomers of each other or They, here let's just draw the two molecules that we're referring to So when I'm referring to this And this, right? They have the same molecular formula But their atoms are arranged in space differently, right? They have the same connectivity Their atoms are arranged in space differently. These are known as geometric isomers, okay? One of them cis, one of them trans, right? Why can this one? Why aren't these Confirmational isomers, you remember? Confirmational isomers are just things that can rotate around and rotate around, right? And get to the same structure. Why can't I go back and forth from these two structures to get to each other? It's a double bond, right? So that double bond doesn't allow free rotation around That in between those two carbon atoms therefore we can't go back and forth between those two structures like we could between These structures here, right? So this is butane that's butane, right? So these we call Confirmational isomers and These we call geometric isomers remember it's because We can't do that, right? We can't rotate around that bond, but here Rotation around that bond is permitted, okay? So in other words, these are the same structure or the same molecule, I guess I should say These are different molecules, okay? Same thing goes with cyclic alkanes, okay? So let's build a cyclic alkane and prove or at least Understand what I'm trying to refer to right now. Excuse me Okay, so notice here. I have the cyclohexane structure, right six small six Carbon atoms, so that's hexane, right? It's in a circle, right? So we call it cyclohexane, okay? Notice I have these two green atoms these two chlorine atoms on the one side here of cyclohexane We actually call this sys Okay, because they're on the same side, okay? Just like the geometric isomers. We call sys okay can we Rotate around this bond and make the transversion right so in a regular alkane We can rotate around that bond right and go back between the two isomers right, but in a cyclic alkane. I actually have to Break the bonds and move them. Why is that? Why can't I go back and forth because? Right, there's no free rotation because it's in this cyclic structure, okay? so I'm going to let you guys play with this and Hopefully you want we'll try to get it to having those chlorines both on either the bottom side or the top side of this Okay, and hopefully you'll be able to see that you can't do that. Okay, so in fact in cyclic alkane, there's the type of isomerization Geometric isomerization that you see in alkenes because there's no free rotation around that sigma bond Normally around sigma bonds you have free rotation, but here you can see similar pattern of geometric isomerization occurring in this cyclo pentane structure here We have the methyls on the bottom of the ring right and Here we have the methyls one on the bottom and one on the top You can't go back and forth in between those two structures. So they're both Their own unique structure. They're their own unique compound. Okay, they have different properties from each other so We refer to them just like we refer to the alkenes as cis and trans okay, so like this one here if you don't mind for a second This would be known as the trans version right because the green Atoms are on the top and on the bottom if I were to change this So this structure This is the cis version. Okay So geometric isomerization doesn't only happen in alkenes, but you see it also in cyclo alkenes Okay, so let's talk about some properties of alkenes fairly quickly. These are all non polar molecules With very weak intermolecular forces. They don't like to kind of interact with each other very much They're not soluble in water In fact, I'm going to give you a new term Hydrophobic, okay, so when things aren't soluble in water you call them hydrophobic right phobia phobic like phobia right like being afraid of hydro like water Okay, so a hydrophobic molecule is like afraid of water Okay, so it doesn't like to be around water the other type of molecule The ones that like to be in water or dissolve readily in water. We call those hydrophilic molecules Like philic like in love with okay, so There are some molecules that are hydrophilic which can dissolve readily in water others which are hydrophobic Which don't dissolve at all in water Alkanes have a very low density less dense than water That's why when you mix alkane solutions with water the alkane will Float on the top of the water because they're less dense than water Melting points and boiling points increase with molecular size and if you can see this picture You can see the little oil droplets Floating on the water representing the density difference Okay, so some properties of alkane These the least reactive or of organic compounds all are other organic compounds react much more readily Although we do use alkane quite significantly in combustion reactions, so like The propane yeah, you like that that picture is awesome the propane that this gentleman is using to grill his hamburgers is Alcane Lighter fluid is an alkane a Lot of things gasoline is a mixture of alkane Methane of course what we use in the Bunsen burner and to Heat our homes is also an alkane, so all of these reactions are combustion reactions. This is the main reaction that you find alkanes Doing okay, so let's talk about aromatic compounds Aromatic compounds So we're just doing a survey of all of the different functional groups right now, right? So aromatic compounds look a lot like alkene Okay, so hopefully you guys can see the similarities between alkanes and aromatic compounds already Right, so if we look at this compound here, this is benzene if you guys have ever heard of that molecule one of the most stable molecules Organic molecules, which is why it's so carcinogenic as a matter of fact but Anyways aromatic compounds you can see so this is the bond line form of benzene right and this is this Lewis structure of it. Okay, so hopefully you guys can convert back and forth by now so Remember, what is an alkene have what's an alkene's functional group? Anybody remember what the alkene's functional group is Why does the benzene look like an alkene? Because it has a double bond right So what's the alkene's functional group again? Double bond okay, so if you don't know that and you should probably be thinking about Functional groups instead of the other things you're thinking about Okay So here You can see how many you can see three double bonds there, right? But notice we don't call this an alkene That's weird, right? We would think that you'd call this an alkene, but in fact when you've got Alternating double and single bonds that gives different properties to these types of molecules, okay? so in other words Aromatic compounds contain a ring type structure that has alternating double and single bonds So you're going to be asked to recognize these So an aromatic compound Contain a benzene ring or a derivative of benzene, so you'll be looking for this type of a structure Okay, if you see that then it's aromatic There's another So anything that any other compound that's not aromatic we call we give another name to it's called aliphatic So all those other compounds that we've learned before Aromatics those are all aliphatic compounds anything we learn after aromatics. They're called aliphatic compounds Okay, so aromatic structures are very very a unique structure. Okay, so that's why we Have broken them up into their own division Okay, so There's benzene right so you can imagine drawing it like this or like this They're equivalent structures Okay, and as a matter of fact a lot of times you'll see benzene drawn Because in fact neither one this one or this one correctly represents what benzene looks like in fact It's a hybrid between these two structures, and a lot of times you'll see people just draw it like this Okay, so with it's like a cyclohexane with a circle in the middle These are known as Kekule structures, and that's just after some dead guy. Okay, some dead guy's name was Kekule He was the first guy who thought of benzene Being like this alternating double and single bonds he had a Crazy dream apparently he was thinking about this his whole life and one night he woke up in a cold sweat like screaming because he was having dreams of a snake chasing its tail around and around and around and around and He realized that that was the you know deduction that he needed to come up with this Structure of benzene before this benzene structure was very Highly debated okay, he came up with this one night while he was asleep That's why So much praise is given to him by these structures Okay, so Here you can see some benzene derivatives Right, so these are all aromatic compounds. Hopefully you can see the aromatic portion of the compound Notice the name here ethyl benzene. Why do you think it's called ethyl there? Because it's got that two-carbon chain off of it right anything with a two-carbon chain is called an ethyl group, right? Okay, so there's some other ones. What do you think this group is called here? Nitro group right? You ever heard of nitro, right? Grand Theft Auto or whatever right? That's what you're putting in your car You ever heard of TNT TNT try nitroglycerin Notice this group here C6H5 Okay C6H6 is Benzene's molecular formula whenever you see this C6H5 hanging off of something That's saying there's a benzene ring hanging off of that. Okay, so this is another way to write it C6H5 So in other words instead of writing this structure here I could have just put C6H5 there and I would have expected you to realize that that's benzene Okay So in other words, there's two coming off of that same carbon right there Let's draw that structure up there. So that's the cyclobutane structure, right? Everybody hopefully can See that so that's what that structure looks like in aromatic compounds. We also have structural isomers. Okay, these are molecules that have the same Molecular formula, but the atoms are arranged differently in space. Okay, notice here. We've got these three Di-bromo benzene derivatives, okay Here we have the bromines on these two carbons Here we have the bromines on these two carbons. So here. There's no carbon separating them here There's one carbon separating them here. There's two carbon separating them. Okay The different structural isomers if you're in the one two positions or positions where there's no carbon separating you You call that ortho. Okay, or oh So this is ortho derivative, okay If you've got one carbon between you you're called a meta derivative or M Okay, so they're ortho so zero carbons between meta one carbon between and the last one is P or para and that's two carbons between So do you guys see why this one's called an ortho benzene? You guys see that This is a meta benzene. This is a para benzene So what would this be ortho meta or para meta? Okay, so it doesn't necessarily Mean that you have to have the same groups here and here. Okay So if I were to ask you what about these two chlorines here and here What are they in relation to each other or though? Is that cool? Everybody got that. What about those two chlorines? Meta and what about those two para? Okay, so you should be able to do that with any of these things We'll talk about I don't know if we'll talk about this one two three four five naming system Here's some properties of aromatics nonpolar hydrophobic a Number of vitamins that we need for our everyday living, right? are aromatic compounds in fact Very very extremely high number of bio molecules are aromatic compounds all of your bases and DNA are aromatics a Lot of your amino acids and proteins are aromatics and a lot of other molecules that are endogenous to the human body are also aromatics and Then we'll talk about these poly aromatics. These are just benzene rings stuck to each other We call them poly aromatics because there's many benzene rings So that's a so one before you guys leave if you don't mind We have we have two classes that we've gone over so far unsaturated hydrocarbons these are alkenes alkines and aromatics and Saturated hydrocarbons just the alkane so this is the survey of the four different functional groups that we've talked about so far and We'll go on to Some others later Thank you, sir Make sure you sign the list before you get out of here Thank you. What's up here and? Hopefully I'll be done grading your stuff in a couple hours Okay, if you want to Come up to lab for the buffer or the fats lab. I'll be there at 11. Oh So you're gonna have to wait until after