Okay guys, good morning everyone, hopefully everybody had a happy Thanksgiving break and hopefully you're really excited to be back and finishing up the last two weeks of school. So let's continue our discussion about bonding patterns and organic molecules. So if we look up here, we can see here these pictures are similar, so what we call these are ball and stick models. They're similar to what we've built here, okay, these little toys. They kind of represent what molecules look like and behave like, okay, they represent it. Recall this is not an actual molecule, okay, so it doesn't, it's true. I mean we think of these, okay, yeah, it does all these things that a molecule, it has all these properties that a molecule has, but the thing is is we want to remember that this doesn't necessarily represent all of the things that a molecule is, okay, it represents a lot of them, okay, so we don't want to, I know it seems funny to say, yeah, this isn't really a molecule, but the thing is is when we use these more and more and more, we say, oh, okay, since it does this and the actual molecule must do that and it's not necessarily the case, okay, but it does give you a good idea about the properties and the principles that the molecules behave along, okay, so we've got these ball and stick models. So remember, when we look at these models, usually we have black balls representing the carbon atoms, white ones representing the hydrogen atoms, okay, and remember organic molecules are consisting of carbon based structures, okay, so that's what we're talking about, okay, so when we look at these models, what we, what we want to recall is that we can take, you know, if we did some sort of chemical reaction, we could take maybe one of these hydrogens and replace it with a big carbon group like this, okay, and instead of having a hydrogen there, bam, now we've extended that molecule and made a bigger molecule, so does everybody see what I've just done? Okay, so what we, what we can think of by doing this type of representation of these things is realize, hopefully, that if we are able to be creative with our reactions, we can actually build organic molecules to immense sizes and and have immense different structures, okay, so different structural possibilities, so we don't necessarily only have to have these what we call straight chain molecules, okay, very simple molecules, we can have very structurally diverse and structurally interesting molecules, so what they say is like organic molecules range from very simple molecules like CH4, which is essentially the simplest organic molecule, so very complicated molecules containing over a million carbon atoms, like your DNA or proteins or things like that inside of it, okay, we talked about isomers last time, but I want to revisit it because we're going to be talking about it a lot today, so isomers recall our compounds that have identical molecular formulas, but different arrangements of the atoms in their structure, okay, so we see here these two molecules, if you want to look back to what our discussion was on last Friday, was that both these molecules, their molecular formula are C2H6O, okay, but you can see that they're structurally built differently, okay, so you guys see that the oxygens in this one's in the middle and on this one it's not in the middle, right, and in fact these are two different structures, recall this ethyl alcohol, this is the stuff that's in like booze, right, get you drunk, this stuff here, dimethyl ether, this stuff will kill you, okay, so you remember we were talking about like whether you ingest this stuff, this stuff will kill you, this stuff will get you drunk or whatever, okay, but they have the same molecular formula, they're both very small molecules, you would assume that they have similar properties, but unfortunately that assumption isn't correct, right, so what we say is that since they have the same molecular formula, the different con activities, we call them structural isomers, okay, so this is the type of isomerism that, which the atoms, the bonding patterns are different in the structural formulas, okay, and remember these are ball and stick models, it says ethyl alcohol is a liquid at room temperature and is completely soluble in water, so this stuff, whereas dimethyl ether is a gas, so this stuff's a gas and only partially soluble in water, so they have even different properties there, okay, so let's extend our knowledge and our thinking about structural and different types of formulas actually, okay, so we talked about structural formulas, those would be represented like by the structures or the molecules that I have here on the desk, okay, so this molecule here, this is butane, C41234H12345678910, okay, C4H10, that's butane, so let's look at some other ways we can represent butane, we can represent it like that, but that doesn't give us very much information about what it looks like, okay, we could represent it like this, the expanded structural formula here, we also know this as the Lewis structure, if you recall Lewis structure from a while back, these show the atoms with all the bonds, notice here we're showing that straight chain, 1, 2, 3, 4 carbon atoms, do you guys see that, so it's the same thing here, 1, 2, 3, 4 carbon atoms, okay, so why don't we pass this around while we're looking at this slide, and you can compare what you see there in the ball and stick model to these other representations of butane, okay, now we have the condensed structural formula, this formula lists the atoms in the order implying how they're bound together, so it shows the connectivity of the atoms, okay, so let's take the one formula, so the Lewis structure here, and let's condense it to the condensed structural formula, so if we take this piece here, condense that down, we say CH3, like that, okay, so you can write it like this, like how I wrote it, or you can write it how they wrote it, CH3, like that, okay, so now we'll take the next piece, okay, and then write it next, CH2, okay, then what do you think, CH2, right, and lastly CH3, very good, okay, so that's more of a condensed structural formula, so it doesn't, it's not as expanded as this, so it doesn't take up as much room, it doesn't take up as much time, but it gives us very similar information, okay, but we have to recognize that those H's are bonded to that particular C and whatnot, we can also represent this in a different way, still called the condensed structural formula, but if we know what the way structural formulas are put together, we can say, well, there's one of these, and then we've got two of these in between another one of these, so we can take these two and represent them as an equivalent representation, so we just put parentheses around CH2, like that, then we count them, one, two, so we've got two of them, so we put a two there, CH3, again, that gives us very similar information to the other, whoops, the other representations, either one, I can, I can translate either one into chemspeak, okay, from English, so, yeah, either way is fine with me, just if you're doing the condensed one, make sure that you know, like, the groups that you're representing in, like, brackets or whatever, okay, so if you're not sure, just do write the expanded condensed formula, okay? Okay, so what would, why can't we do that? Somebody help us out. Why can't we say this, this, this? Does that tell us what this thing looks like? No, it doesn't, because this, these two aren't on, like, next to each other, okay, so that's not, so if you wrote that, that's no good, okay, so you got to write it in a way that represents it, represents the way it looks, okay, so that's what we're trying to do, okay? So is everybody cool with those three types of structures, the structural formula, the Lewis structure and the condensed formula, okay, of at least butane for right now? Okay, so let's, let's take our thinking to the next level, okay, this is the bond line formula, okay, I know we talked about this briefly last time, but bond line structures show all the atoms except for carbon and hydrogen, and that always shows the bonds, okay, carbon and hydrogen are implied, okay, so you're going to see a lot of these bond line formulas not only in this class but from now on in your chemical education, so you're going to have to become very familiar with these, okay, so if you go into any other biology class or any other class really that has to deal with health or welfare of people, you know, they're going to be representing things like this, so we've got to get our thinking to this level now, okay, so we can represent, these are all remember the same thing, okay, let's represent it again, this is the same molecule, okay, so what is this representing, representation showing us at the end of each line, so each line is a bond, okay, each line is a bond, at the end of each line like here and here, right, that's a carbon atom, okay, and where two lines connect like here and here, that's also a carbon atom, okay, so let's just take this structure and put the carbon atoms in just so we can think about what it's actually telling us, okay, so C, C, C, C, now remember if I told you to write the bond line structure, I wouldn't want these C's in here, I don't want any H's, okay, we're just going backwards to make sure we know what we're talking about, okay, the other thing we need to remember and we always have to remember this is that carbon can make four bonds, okay, carbon will always make four bonds, nitrogen will always make three bonds, oxygen will always make two bonds and the halogens will always make one bond, okay, so we have to remember that, if we don't remember that we can't do these formulas, okay, so if I'm looking at this carbon here, how many bonds am I currently showing that it's making? Just one, right, how come, so what did I say, each one of these lines represents a bond, right, how many lines are coming from that carbon? Just one, not three, right, like some people said, okay, it's just one, okay, so we've got to remember though that carbon doesn't make only one bond, right, how many bonds does carbon make? Four, okay, so it needs three more bonds to it, okay, those three bonds are hydrogen, okay, bonded to hydrogen, so, but remember they're implied in the bond line structure, okay, so I'm going to write the original bond line structure up there and we're going to compare it to what we're writing here, remember this is essentially this expanded structural formula, what we're about to write out here, okay, so if we're looking at this carbon, how many hydrogens does that carbon have on it? Two, how do you know that? It's already got two bonds, right, so how many bonds does carbon need to have? Well, four, two plus two, right, so we're going to represent those as H and H, okay, so if I wanted to write just as an aside, okay, if I wanted to write my Lewis structure or something like this and I was kind of being lazy or something like that and I represented it like this, okay, does this represent the same thing that this does? Do you think or not? Do you think it does? Okay, what did I tell you guys when we have at the end of a line that nothing is there? That's a carbon, so is this the end of the line with nothing there? Yeah, so does this represent the same thing that this does? No, okay, so that's one kind of annoying thing, right, that if we just put a line, it doesn't mean it's a hydrogen. It actually means it's something else. It's actually a CH3 group, right? CH3 group at the end of every line, right, CH3, like that. Okay, we call CH3 groups methyl groups, okay, so if I slip up and say methyl group before I teach you about them because we're going to go over all of them in a little bit, that's what I'm talking about. So a CH3 group, this is called a methyl group. We'll go over the other ones in a little bit. So if I represent something like this, what I'm really saying is that there's a methyl group at the end of every one of these lines, okay, does everybody understand what I'm trying to say there? Okay, so you've got to be very careful when you're drawing structures, okay, so it's kind of tedious at the beginning but when you learn how to draw bond line structures, it's very simple, okay, because it's just, okay, and you always want to be drawing your bond line structures like Charlie Brown's little, you know, shirt thing design, okay, so if I have like 20 carbons, I go one, two, three, four, five, six, seven, eight, nine, ten, you know, all the way until 20, okay, pardon. Well, if I say bond line formula then you don't put carbons and hydrogens, right, because carbons and hydrogens are implied. If I wanted, I would probably never ask you to do C20 in like this type of a formula, this Lewis structure, because it would take you forever to write that thing, you know, and I'd be getting the same redundant information that you already know how to put Cs and Hs on there, so it won't help me out in seeing what you guys know. Okay, so are we cool with bond line structures now? I put them this, like this way, because the bond angle is 109.5, right, so if I put it like this, it doesn't represent the structure as well, I mean, but that's not wrong, you know, so, okay, yeah, yeah, definitely. Okay, so is everybody cool with this? Everybody realize that every one of these structures besides this one that we've written up on the board this morning is the same structure, right, okay, so it's representing the same molecule, butane, the stuff that comes out of the lighter, okay, so this here, this, this, this, and who has my butane out there, okay, and this thing here all represent the same structure, okay, okay, so let's move on. So here are some bond line structures, okay, here's a slide of bond line structures, obviously some of them are more complicated than others, right, so if you look here, this structure is that structure that we just showed, butane, okay, well let's look at this structure here, cyclohexane, okay, everybody draw the bond line structure in their notebook or whatever, and everybody tell me what's the molecular formula of that molecule, okay, so how many carbon atoms does this molecule have? How do we figure that out? How many carbon atoms? So, six, hopefully everybody's saying six, does everybody see that it's six atoms, right, because why? Because we've got one, two, three, four, five, six carbon atoms, right, okay, so we're going to say C6, remember we're trying to draw the molecular formula, okay, so how many hydrogens does this molecule have? Twelve, right, yeah, so on each carbon, right, there's two hydrogens, so this is, this is cooler, right, this is much cooler than doing a bunch of math problems, right, that's why organic is so awesome, because you don't have to do math problems except for add two plus two plus two plus two plus two, right, so does everybody understand where we got 12, or 12 from? Two, four, six, eight, ten, twelve, okay, so everybody now, how about why don't you take this structure and represent it as its Lewis structure or its expanded structural formula, and if you, you can't think about that, go back to the last slide and look at how we went back and forth, so is this structure here the same as this structure here? No, why not, because I have to put my hydrogens in, right, because here I'm implying they're all methyl groups, right, so let's draw them in, like that, so is that what everybody else got, hopefully, that's not what you got, no, well that's what it looks like, okay, okay, well if you didn't get this, this is what it looks like and this is what you will draw from now on, when you see cyclohexane, okay let's try this one now, so we're just building up, okay, I know this is not what everybody got, but does everybody understand why this is the structure, do you understand why this is the structure, yeah, did you pardon, oh that's alright, nobody instructed you how to do that, yeah, so now you're miles ahead of where you were five seconds ago, so, okay, so are we cool with this, can I erase, okay, so how many bonds does each carbon atom need to have, four bonds, okay, so I want you to draw that next cyclic structure, this one, showing all your hydrogen, tell me what the molecular formula of that molecule is first, C8, whoops, don't jump to conclusions, right, don't jump because you know about the last one, okay, so it's C8, that's right, but it's not H16, yeah, so what is it, H14, why is that, what are we saying with these two lines in between these two little, that there's a double bond, right, there's a double bond between those two carbon atoms, so when we put our carbon atoms there and there, how many bonds does each of those atoms have, how many are there, well, okay, how many are represented on that structure right now, how about that, okay, they each have three bonds represented on this structure right now, right, so let's put the other bonds in, right, so now it has four bonds, so everybody see this, that it's got three bonds, now it's got four, okay, now draw the rest of it, is that what yours looks like, hopefully that's what yours looks like, oh, one other thing, a lot of times, you know, okay, you got your problem on your paper here, right, so it's going to be at the top of your paper like this, okay, so there's your problem, right, a lot of times I'll be writing, you know, and I'll be on a test, I'll be writing this way and then because I'm drawing things, I want it to look nice, I'll turn it this way and then draw it like this and turn it upside down and draw it like this, right, but remember, we're representing letters, right, and in English, right, a C looks like this and doesn't look like this, so if I turn it upside down and draw a C, it's going to look like this, does everybody see that, not only that, but probably more importantly, an H looks like this, right, but if I turn my thing to the side and I draw an H, it looks like that, right, which now looks like a different element, okay, this is iodine, okay, so a lot of times people misrepresent what they're trying to say by turning the paper in such a way that makes it look like they're drawing a different, you know, alphabetical symbol than what they actually are, okay, a different letter than what they actually are, so whenever you draw things, make sure you're drawing them not like this, you know, but like this, okay, like we normally do when we're writing English, okay, so try these ones, these three on your own, I know they're much harder, well these two are, that one shouldn't be much harder, and we'll see if you got the right answers tomorrow, okay, or on the Wednesday, I mean, okay, so let's revisit functional groups, recall, functional groups are any portion of a compound that contains either multiple bonds, so that means pi bonds, okay, heteroatoms, do you guys remember what heteroatoms are? Anything that's not carbon or hydrogen, okay, heteroatoms, so any portion of a compound that contains either multiple bonds, heteroatoms, or a grouping of heteroatoms, so notice if we stick this, we take one of these hydrogens off, right, and we stick an OH there, does that have a heteroatom in it? What's a heteroatom again? Hydrogen, right, what about everybody else? What's a heteroatom? Not carbon or hydrogen, is this, does this have a heteroatom in it? Yes, right, what does it have in it? Wait, what heteroatom does it have? Wait, a heteroatom is anything that's not carbon and hydrogen, so it can't have carbon and hydrogen and be a heteroatom, that doesn't make sense, right? Okay, so let's try this again, so what heteroatom does this thing have here? Oxygen, okay, so do we consider this a functional group then? Come on, everybody been telling me about heteroatoms, they're functional groups, right, let's put them all together now, okay, so is it, if it's got a heteroatom in it, does we call it a functional group? Yes, okay, cool, okay, so we're looking here, this is a functional group, right, because it's got this heteroatom, what about this? Is that a functional group? Yeah, because of why? Because it's got a heteroatom, right, everybody tell me, okay, and this one, is that a functional group? Yes, yes, why, why? Because it's got an oxygen in it, right, and why is, what's an oxygen called? A heteroatom, thank you, okay, cool, so let's look at the different functional groups, okay, or different molecules, types of molecules that have these different types of functional groups in them, so alkane is a type of molecule that has no functional groups in it, okay, that's just like this molecule here, right, butane, do you see other atoms besides carbon and hydrogen are represented by different colored balls, okay, so do you guys see any functional groups in this molecule here? No, why not, because they're only black and white, right, okay, cool, so this is called an alkane, okay, we're going to go over those in more detail later, okay, no functional groups, so only one that doesn't have a functional group, functional groups are what, what are functional groups? Heteroatom or, or what, what's the other one? Multiple bonds, thank you, very good, okay, oh, some, some people are listening, okay, so does this have a functional group in it, can you guys see that, what is it, what's the functional group, okay, well I'm just going to chill until you guys tell me, okay, well these guys can, you guys can see, double bond, yeah, you can see way over there, right, 2020 vision, what about that one, okay, that's a triple bond, right, triple bond, if you can't see, you've been sitting there the whole term, you know, come sit over here, maybe you can do better in class, okay, so this one here, this got multiple bonds in it, right, so that's a functional group, this one here, see the heteroatom, that's your functional group, heteroatom functional group, heteroatom, do you guys see it, yeah, it's the nitrogen, right, it's a functional group, see the heteroatom, so this whole thing actually is the functional group, see that heteroatom, functional group, right, heteroatom, heteroatom, functional group, more, more, more, okay, so let's talk about hydrocarbons in general, hydrocarbons are just what you would think the name implies, it's a structure that contains only carbon and hydrogen, so if you've got a compound that only contains sigma bonds, you guys remember what sigma bonds are, single bonds, okay, if you only have single bonds, those are called sigma bonds, or the first bond in a double bond, okay, so if we look at the double bond here, do you guys see that double bond, so the first one is called the sigma bond, the second one's called the pi bond, okay, so it doesn't, it's not like the bottom one is a sigma bond, the top one's a pi bond, it's just whatever one is whatever one, okay, so a double bond is made up of two types of bonds, one sigma and one pi, a single bond is only made up of a sigma bond, okay, when we come to a triple bond, that's made up of one sigma bond and two pi bonds, yep, after the sigma, they're all pi, so you got single bonds which are only sigma bonds, double bonds which are sigma pi and triple bonds which are sigma pi pi, okay, so like what it says here, any compound containing only sigma bonds is said to be saturated, so this is kind of a term that we use to define these things, we say saturated hydrocarbons, those are alkanes essentially, saturated hydrocarbons are alkanes, but we can have hydrocarbons that are unsaturated, which means that they must have at least one double bond or one triple bond in them, because unsaturation means that we have at least one pi bond, does that make sense, okay cool, so notice here we've got this thing which is saturated or unsaturated, unsaturated, what about this one, saturated or unsaturated, unsaturated and this one, saturated, very good, okay, so this one is an alkane, right, these ones are what we're going to go over now, this is called an alkene, this is called an alkan, okay, so an alkene, an alkene or the older name is called an olefin, these are compounds that contain at least one double bond and ethylene which is represented here is the simplest alkene, you can see it in its Lewis structure here, you can see it in its bond line structure here and then its space filling structure here, so and then the last thing we'll talk about today, but don't leave yet because you still got to sign in, the sign-in sheet, so we're going to talk about the general formula for internal and terminal alkenes, okay, so we say internal or terminal alkenes are alkenes that come at the end of a carbon chain like this, we're looking at bond line structure, do you see the alkene coming at the end of the chain there, okay, that's what this is representing here, okay, well this one specifically, right, because here we've got two hydrogen atoms and here we've got one hydrogen atom, right, so do you see those three hydrogen atoms there, that's the general formula for it, that are, that's just whatever, okay, that's just like that's the whatever group, it can be anything that's a carbon chain, okay, so notice here with this one we've got a terminal alkene because we've got it at the end of the carbon chain, okay, we've also got a terminal alkene here at the end of the carbon chain, except there's two R groups, so if we drew the bond line structure it would look something like this, okay, but it's still at the end, okay, it's at the end of two chains at that point, that's just saying this R, this R can be different than this R, okay, so this little thing says this doesn't necessarily need to be the same thing as this, this can be like a methyl group and this can be something much bigger if we want it to be, okay, and the other one saying this can be different than this, then this and this, okay, internal alkynes notice are not at the end of a chain like that, that's something like this, essentially this, right, and then the other one we've shown, whoops, is having it on all sides like that, okay, so what I'd like you to do is look at these and try to tell me whether you find the alkynes as a terminal or internal alkene, okay, and we'll get to geometric isomerization next time, if you guys could just chill for a second, what you've got, so I have a evaluation that you guys shouldn't take you very long to fill out, but if you could answer honestly and then when you finish filling this out you can come up and sign your name in, okay, so I won't let you sign your name in until you finish this, but this is for the SI instructor, Inaz, okay, so Inaz Rodriguez, if you know who she is, she helped us out this term, this is not for Sherry Wong, if you went to her at all, okay, so this is only Inaz, so I'm going to pass these out, if...


Direct-alcoholine alcohol fuel cells, DAFQs, have gained popularity due to their favorable reaction kinetics in alkaline media, higher energy densities achievable, and ease of handling liquid fuels. Despite the high energy density available during the oxidation of polycarbon alcohols, these compounds are difficult to oxidize. Conventional precious metal catalysts such as platinum and platinum alloys, as well as less expensive palladium, gold, and silver metal catalysts have been explored. Lanthanum, strontium oxide, and perovskite-type oxides have also been investigated. Polymer electrolyte membranes are commonly used in DAFQs, unlike conventional proton exchange membrane fuel cells. The performance of DAFQs using various alcohols, catalysts, and membranes, as well as operating parameters, is summarized. Further development of catalysts, membrane materials, and fuel cell systems will be necessary to increase the power output of DAFQs. This article was authored by Eileen Howe, Keith Scott, and Ulrika Krueger. We are article.tv, links in the description below.


A Place of Greater Safety by Hillary Mantell, narrated by Jonathan Keeble. The author begins with the following note. This is a novel about the French Revolution. Almost all the characters in it are real people, and it is closely tied to historical facts, as far as those facts are agreed, which isn't really very far. It is not an overview or a complete account of the Revolution. The story centres on Paris. What happens in the provinces is outside its scope, and so for the most part are military events. My main characters were not famous until the Revolution made them so, and not much is known about their early lives. I have used what there is, and made educated guesses about the rest. This is not, either, an impartial account. I have tried to see the world as my people saw it, and they had their own prejudices and opinions. Where I can, I have used their real words, from recorded speeches or preserved writings, and woven them into my own dialogue. I have been guided by a belief that what goes on to the record is often tried out earlier off the record. There is one character who may puzzle the reader because he has a tangential, peculiar role in this book. Everyone knows this about Jean-Paul Mahat. He was stabbed to death in his bath by a pretty girl. His death we can be sure of, but almost everything in his life is open to interpretation. Dr. Mahat was twenty years older than my main characters, and had a long and interesting pre-Revolutionary career. I did not feel that I could deal with it without unbalancing the book, so I have made him the guest star, his appearances few but pecan. I hope to write about Dr. Mahat at some future date. Any such novel would subvert the view of history which I offer here. In the course of writing this book, I have had many arguments with myself about what history really is, but you must state a case, I think, before you can plead against it. The events of the book are complicated, so the need to dramatize and the need to explain must be set against each other. Anyone who writes a novel of this type is vulnerable to the complaints of pedants. Three small points will illustrate how, without falsifying, I have tried to make life easier. When I am describing pre-Revolutionary Paris, I talk about the police. This is a simplification. There were several bodies charged with law enforcement. It would be tedious, though, to hold up the story every time there is a riot, to tell the reader which one is on the scene. Again, why do I call the Houtel de Ville City Hall? In Britain, the term Town Hall conjures up a picture of comfortable aldermen, patting their paunches and talking about Christmas decorations.


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