Lecture 09. Organic Compounds
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Transcript: English(auto-generated)
00:06
Folks, if you cannot hear me, okay, let me know. Because some people told me last time, after lecture, that you have difficulty understanding me through the volume, and we can solve that problem by jacking up the volume. If
00:25
you can't understand me because of my accent or because of my slurring of the words, I cannot help you with that. Important information Midterm one, next week, next Friday. Time flies. Next week on Friday is the midterm. October 26th. Where? Here.
00:50
What time? This time. 2 o'clock. What is it about? Everything we talk about. Easy. Next Tuesday night,
01:03
I'll post a practice exam for you to look at so you can have an idea of what it is. what kind of things you may expect. This is a practice exam. It's a special service, to you, but a special service does not include answers to practice exams because that is not a practice exam anymore. So I'm going
01:26
to regard this as an actual exam to look at it. And an actual exam doesn't have answers that you are wrong. So if you want to mimic the real situation with the same, so don't ask me for the key to this, I'm not going to give it to you.
01:52
How many questions? Well, the practice midterm will tell you exactly that. It gives you the length of the midterm and what kind of topics you will be questioned about. Yes?
02:11
When and where? You can access it on the class website where the lectures are posted. That's where it will be posted.
02:22
Next week is going to be a very funny week. Very funny week, for two reasons. First, because of the midterm. Second, because I will be partially out of town at least as well. I really have to, for very important reasons, have to be in Washington DC. I kind of physically will be here, I'm working things out,
02:47
maybe a replacement or not. We'll figure it out. But, in terms of the homework, that homework for next week is not due on Friday, like this week, and the way we usually do it, but it will be due on Wednesday. Homework 4 is due on Wednesday at the same time.
03:07
So please take note that homework is important because it will actually, you know, train you on the material that we will cover later. So it contains stuff we talked about today.
03:24
So take note of that. I'll post an announcement in several places, but if you forget about this, then this is from now on your own responsibility. And then, next Thursday night, 7 p.m.,
03:41
next Thursday night means the week from now, in this particular auditorium, which is not this one, this is physical sciences, this is humanities lecture hall, 100A, I'll do an in-class review session. So you're welcome to join us, it's now mandatory by any
04:01
means, but if you feel like, on the eve of the midterm, you'd like to have some time. and you want to discuss a couple of examples, then that's the time to come to that classroom and discuss. Okay, so I'll give you more information on Friday,
04:21
what we'll do with the lecture next week. All right. We will move on with the next topic, which will be on midterms, so please be patient, and that's about organic molecules. We introduced compounds, we started with ionic compounds, and then we moved on to compounds that have covalent linkages.
04:45
Covalent compounds are just simply molecules. And a very important class of these molecules are organic molecules. We know them, they are all around us. For instance, this is charcoal organic molecules.
05:01
Here's one, it looks like a molecule, and if I draw this in a particular way, in terms of particular atoms and their forms, it looks like this. This is a sort of line structure. This is vitamin C, a very important molecule. It keeps you healthy. You don't need that. You don't need these things. After a while, you get sick. Because you don't have vitamin C, your body cannot make
05:23
vitamin C itself, and you need to take it in through the consumption of these kind of materials. This molecule is an organic molecule. What is an organic molecule exactly? The definition of an organic molecule is a molecule that contains carbon and a couple of other elements. Typically, hydrogen, oxygen, nitrogen,
05:45
and allergens. The basic ingredient is a carbon atom. Covalent compounds with a carbon atom. So here's a person called Frédéric Boudet, and he claimed to be the first person that made an organic molecule. It's very interesting to tell you, but it's true that
06:09
before that time, before this particular experiment, I'll come to this in a couple of seconds, people thought that organic molecules could not be made by man. Organic molecules were made by nature, whatever you want to call that, but man could not be made by man.
06:27
That was verbally. So this person's friend says, well, I'm not sure that's true, let me experiment a little bit in my lab. He took this, which is an inorganic compound. And then he was heating this up, and he made this compound, which we would classify as organic. It
06:45
has carbon here, and it's a neutral compound. A neutral molecule, all the bonds are created in the link, that means this is an organic molecule. It's called urea, the basic ingredient of urine. So he was very happy and he joked about it that he made, basically,
07:05
urine. He made urine in the lab. He was extremely excited. You can read this quote, and feel free to laugh if you want to, but this is the birth of organic chemistry. The first organic molecule to be synthesized was the urine molecule.
07:25
All right. So why are organic molecules made of carbon? Why is carbon such an essential element? Everything to do with the properties of the element of carbon. The atom, the carbon atom has a particular
07:40
property that makes it an extremely suitable candidate for forming a wide variety of very stable, robust molecules. carbon likes to make bonds, and these bonds are typically covalent, which means strong. A strong bond. Strong bonds means molecules that are very stable. They don't fall apart. And that's good. Because if you want to build something, you
08:04
don't want someone to want it to fall apart. So carbon does that and makes these very strong covalent bonds. It also can make covalent bonds not only with itself, but with other carbon compounds, also with a wide variety of compounds. of other elements. So you can make a whole flurry of different types of molecules from these very simple principles. So
08:29
these bonds can make structures that have very interesting geometries, which again contribute to the stability of the molecule. Here's the benzene ring, which has this hexagonal structure, this is a typical alkane, which has a particular kind of like zigzag kind of structure
08:46
you see here, another circular structure and even these kind of helical structures. Carbon supports it all. So the bonding is very unique, a wide variety of possibilities, and stability. So carbon is very dependent on these organic molecules.
09:05
This is a list that is reminiscent of what you've seen in high school, I hope These are alkanes. These are very basic organic molecules composed of carbon, atoms, and hydrogen atoms.
09:20
Oh, you had a question, right? Where was the question? Sorry. I will... you have to use a calculator, frankly, because you should do calculations. I will give you very precise instructions on what you need to take with you and not on gravity.
09:41
Any specifics, please ask me on fire. All right. So this list is something that this I hope you've seen in your high school chemistry classes. We will not very actively use this, but please know these structures and be familiar with them. So when I say it brings to the word heptane, you should not be completely
10:02
confused, like what's going on. Heptane is an organic molecule with seven cards. That's kind of like the thing you would like to remember. There's a question actually in homework 3 about these alkanes, just to let you know that these structures, you know, you should be able to work with them.
10:25
Okay. Now, there are common bonding patterns in organic molecules, and this is something that is very useful to keep in mind. So, the hydrogen atom, where it's part of an organic molecule, always has one bond.
10:44
So we indicated with this covalent linkage. So the number of bonds is what? Carbon has four. The number of bonds that carbon has is four. It can have four bonds in this geometry, that means four different bonds, single bonds, four single bonds, or two single bonds and one double bond,
11:06
a total of four again, or a triple bond and a single bond. Also a total of four. In all cases, a total of four bonds. It's a very generic trend, and therefore we typically say carbon has four bonds. There are exceptions. There are exceptions. But for all intents and purposes, you are going to assume carbon has four bonds.
11:28
And it also says lone pairs, 0, 0, so these atoms have no lone pairs. Here is an atom, an element that does have a lone pair, yes, but yes,
11:45
it can. Carbon can also form two bonds on this side and two bonds on this side that are both other bonds. That's possible. That's possible. It's a little exotic. It's very exotic, but it's possible. So let's move to nitrogen. These two dots mean two electrons that do not participate in a bond.
12:08
These guys are bonds. So nitrogen likes to have one, two, three bonds, one, two, three, four triple bonds, one, two, three, in all cases, three triple bonds.
12:24
And two electrons that are sitting there are not bonded to anything. These two electrons together are both a lone pair. You may have heard of this. We are not actually requiring you to know this or to draw these things. I'm just going to point
12:40
out that they are really there, and that later on, we have to draw Lewis properties in chem or A, they will be important. For our course, we are not going to test you extensively on the presence of a bond. So don't worry about it right now. Oxygen likes to have two bonds. One, two. Either a single bond or a double bond. It has one, two lone pairs.
13:06
Again, one, two lone pairs. So these are patterns you will find in organic molecules. Over and over again. So recognizing these patterns will be extremely useful if you have to draw an organic molecule. For instance, if you draw an organic molecule where
13:25
the oxygen has four bonds, I'm going to take my red marker and make a beautiful line through your structure. Because that's wrong. Oxygen doesn't do that. Fluorine is a halogen, trust me, it's a halogen element, like fluorine and bromine and iodine. It likes to form one covalent
13:49
bond, typically two carbon in organic structures, and it has one, two, three lone pairs. Fluorine does not have two bonds or three. It has one. Yes? Well, you will learn about that later on, so we will not go into detail. At
14:09
this structure, I'm just telling you that halogens like chlorine, including chlorine, iodine, bromine, have three. Okay? Okay? There's a
14:23
reason for that, but before we can discuss that, we have to talk about electric configurations, and then we will come clear. All right. So here's a chemical formula, C3H4. This is a molecule, an organic molecule, which has three carbons and
14:40
four hydrogen atoms. Now does this chemical formula fully specify what kind of molecule I'm looking at? The answer is yes. Here is one incarnation. And this is actually, for a person who asked about the double bonds, you have to
15:05
do one carbon that has two double bonds on each side. Or one double bond on each side. One, two, three carbons, one, two, three, four hydrogen atoms. This is basically C3H4. However, there is another one, this one for instance.
15:26
one, two, three in which case there's a triple bond between these two atoms one, two, three, four. Four hydrogens, one, two, three, four. These are two molecules that both have this particular formula.
15:42
So it makes sense, at this point, to be able to discriminate the two. Is there a way we can write down this chemical formula and be a little more specific about what kind of molecule we're talking about? Yes, you can do it. And we call that, by writing, the so-called condensed structural formula.
16:03
condensed structural formula. There it is. So how does it work? You start with the chemical structure on the left. Okay? So you look on the left, just like you read a word, and you see the first chemical group is a C with two H's.
16:25
Okay? Because a CH2 functional unit. So I'm going to write that down. CH2. The next one is a carbon. It doesn't have any extra bonds, except a bond with its neighbors, which are also carbon. So I'm just going to write a C here. And then the last group here is,
16:43
again, a CH2. Okay? So CH2. Right there. So CH2, C, CH2 captures this structure. Let's do this one. Okay? So C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, C, The first group on this side, on the left, is a CH3. CH3. The second one is a single C, and the last
17:03
one is a C with an H. So this is CH3, C, CH. Now each of these hormones has four bonds. Each hydrogen has one bond. We have to remember that. So let's practice that a little bit. Here I have a condensed structural formula. Can I draw
17:28
this structure? Or can I sketch the structural formula of this condensed structural formula? Well, this is a structure that has a CH3 unit all the way through the left, then a CHCH, and then it ends again with a CH3. So let me try to do this.
17:48
Here's a CH3 unit all the way through the left, followed by a CH, right there, another CH, and a CH3 to the right. Importantly, there is a double bond. How do I know that there is a double bond? Yes. Each carbon needs four bonds. If each carbon here has only one
18:10
H attached to it, okay, one here, and this bond on the left with this neighboring C, and on the right with this neighboring C, which means one, two,
18:22
three, that needs four. It needs an extra bond. So what is the double bond for this C? Is it on that side, or is it on that side? It must be on this side. Because this C here has already four bonds. We cannot accept another one. So this double bond must be between these two bonds. So it's a little bit impossible, right? You have to use the rule that there
18:45
are four bonds for each carbon. Yes. You don't exactly know at this point. You can assume that, I'll tell you when they're not, but typically they're all in here. Okay? So the question we ask you, structurally ask you, is how many bonds are there?
19:04
Typically, linear structures. This is also a linear structure. CH3CHO. How do you draw that? Okay, here it is. CH3 is the first unit, and then the second unit is a C with an O and an H. The H is always single bonded.
19:23
The O is bonded to the C with a double bond. That's a closed atom. One, two, three, four, the carbon has four bonds. I'm done. You can draw those non-binding electrons that you want, you don't have to.
19:45
All right. Another two. CH3COCH3 I can see immediately, this is a symmetric molecule. It has on each end a CH3 unit. And in the middle, there's a CO unit.
20:00
How do I draw that? There it is. CH3 to the left, CH3 to the right, in the middle, CO. The O likes to have double bonds, carbon, like this. So, one, two, three, four, the total of four bonds for this particular carbon. But this must be the right structure.
20:24
How about this one over here? This is also a symmetric molecule. It has CH3 all the way to the left, and CH3 all the way to the right. In the middle, a CH2 unit, OCH2. How do you do that? There it is.
20:41
CH3 and then a CH2, this is a CH2 unit right here. Okay? It's a C with two H's attached to it. And then an oxygen attached to the carbon. and this oxygen is also attached to the next carbon, right here. So it's sandwiched between two carbons.
21:01
If it's sandwiched between two carbons, it must have two single bonds on each side. It cannot have a double bond on one end. It has two single bonds with this particular oxygen atom. And then, since it's a symmetric molecule, it has a C-H2 and a C-H3. Okay? All right. Now, this is all good and well. So, writing the
21:30
entropic formula is extremely helpful in specifying what kind of oxygen you are talking about. However, things that can really complicate. From much, much larger molecules, the entropic formula can be very long. It becomes extremely hard to
21:46
interpret. So from very large structures, it will be very helpful to have an easy way of doing it. Even better way of writing this formula. And the way to do that is by sketching the molecule at a line structure. Okay? So
22:03
let's look at this particular guy here. This is a C-H3, one unit on the left, C-H2, C-H2, C-H2, C -H2, C-H3. A pretty long condenser for formal. It gets a little messy. So if I do the following, I start here at this point
22:22
which I say is a carbon atom. So each little point of kink is a carbon atom. I don't explicitly write the carbon atom. I just assume one time I see a point, an end point, or a kink, that is a carbon atom. Right? Each corner point and each end point is a carbon atom. Actually, that's a rule right here.
22:46
One, two, so this one must be the CH3 it has one, two, three H's attached. It's not written. So the hydrogens are not explicitly written in this line structure. So how do I know that they
23:03
are there? Because you assume that there are enough hydrogens attached to each carbon atom such that each carbon atom has four bonds. This carbon atom here only has a bond to that side to another carbon atom which means it has three bonds left
23:21
those three bonds left are hydrogen bonds. Sorry, are bonds to hydrogen. So three CH bonds. So this is a CH3. This one here, carbon atom, has one two bonds with other carbon atoms, and there's two bonds left those are bonds with hydrogen.
23:41
So two bonds with hydrogen this is a CH2 this is also a CH2 that's a CH2 that's a CH2 and this guy here, again, is a CH3. So this little wiggle here summarizes this entire molecule. Let's count it. CH3, right here.
24:01
CH2, this one, CH2, there. CH2, there. CH2, there. CH3, end point. Oops, too fast. Here's another one, and talk about circular structures. The only circular structure you're going to be able to recognize is the 6-fold symmetry structure which pertains to benzene.
24:27
C6H6. This is a solution. Each point is a carbon atom. One, two, three, four, five, six. And then there's double bonds, ultimately. On there, on there. So each carbon atom has one, two, three bonds.
24:45
Three bonds already. One bond left. That's the bond with the hydrogen atom. It means that each one has one, one, one, one. One bond with hydrogen. That means a total of six hydrogens.
25:00
So C6H6, this is a solution. Okay. Let's try to figure out if we understand that. So let's draw the structure of the following condensed structural forms.
25:21
CH3, CH, CH, CH3. CH3 is an end point, and then I have two CHs in the middle, so two carbon atoms, and then it ends again in a CH3. So what I have is something like this. End point, one of these CHs,
25:40
another CH, and then at an end point again, CH3. I double bond, once again, because this carbon atom here has one hydrogen bond, sorry, it's bonded to one hydrogen, and to one side with a carbon, one side with another carbon. It has three bonds and needs one more. There must be a double bond. There must be a double bond.
26:03
The same holds for the next guy. So these two carbons want to share a double bond. Every time you see this repetition, CHCH, next to each other, you know there's a double bond between those keys. Because each C has only one ligand, for example. It only has one bond or something else. In this case, hydrogen.
26:28
Okay. Let's go to this one. CH3, CH2, O, CH2, CH3. There it is. CH3. This one. CH2, this guy.
26:41
Oxygen, right there, sandwiched between the two carbons. Then, a CH2 unit, that's this little kink right there, there's two bonds, and then two H's not drawn. And then an end point, which is CH3. Okay. How about this one here?
27:00
It's a circular structure, it's not benzene, because each point here has two hydrogens. What I do is I just leave out the carbons, just make a little corner there, and also leave out the hydrogen explicitly. So this is not benzene, right? Because in the ring, there are no double bonds.
27:24
Each corner point here has two hydrogens attached to it. Okay. Pretty good. We're not done yet, of course.
27:41
Let's draw this one, a little bit more complicated. We're going to ramp it up a little bit. CH3, CH2, CH2, C, Cl2, and then CH2, C-H-O. So I'm starting to recognize patterns in groups. A CH3 group, a CH2 group, a CH2 group,
28:03
CCl2 is like CH2. Instead of the hydrogen, I just have a Cl. A chlorine. So this is the same kind of corner point, but I have chlorines as opposed to hydrogens. And you'll see what it will look like. It looks a little different.
28:23
CH2 is one of those corner points again, and this CH-O I recognize now as a C-bonnet to a hydrogen and a double-bonnet to an oxygen. So this is it. CH3, CH2, CH2, C,
28:41
Cl2. 2Cl. The Cl's are not like hydrogens. They have to be explicitly drawn. Only the hydrogens are left out. Only the hydrogens attached to a carbon are left out. So these guys are drawn. There's a carbon right there, it's bonded to a Cl here, bonded to a Cl there, and then on this side of carbon, that side of carbon.
29:05
This is a CH2 unit again, this is a carbon with one hydrogen, which is not drawn, and then a double-bonnet to an oxygen. Whoa! We got longer and longer. Let's do this. CH3, CH2, CH2, CHF
29:24
okay, which is very similar to this, CCl2. A C with two extra bonds, one H and one C, in this case, chlorine. Okay? And on the other side of this carbon. CH2, CH2, and then CN. CN we haven't seen yet. So we'll see with other amounts. Here it is.
29:44
CH3, CH2, CH2, C with one F, the other one is H, not drawn. CH2, CH2, C with an N. One bond here must be a triple bond between N and C. We have four bonds of carbon. A triple bond in nitrogen is a common pattern, so we're all good.
30:09
All right. How about this puppy? CH3, CH, CH. Hey, CH, CH, I recognize now as something that has a double bond between the two parts, okay? So then a CH2,
30:22
CHCl, that's CH3. Looks like this. CH3, here's a double bond between the two C's, it has one H each. CH2, this is a C with one Cl and one H. This is the unit right there. The H is not drawn. Okay?
30:41
This is a CH stream animal. Doing pretty well. So this is something you should be able to do. Draw these structures from the condensed structural formula. But, what you should also be able to do is to look at the line structure, determine the chemical formula.
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Okay? What does that mean? Well, I can draw this for you and then you should be able to tell me, you know, what is this? What is the chemical formula? So it goes like this. I'm going to count the number of carbon atoms, the number of hydrogen atoms, the number of oxygen, and in this case, chlorine atoms.
31:23
I'm going to write the chemical formula. Here we go. 1, 2, 3, 4. C4. And then the number of hydrogens. So be mindful now, okay? You've got to determine how many hydrogens are there at each corner point. At each end point.
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There's three here There's one there. There's one there. Don't forget this guy. That's a hydrogen 2. Okay? So there's three there. This is an end point. So three plus three, and then another three, that's nine. H9.
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A common mistake is that people typically forget about this H here. Please count it. I'm not done. There's one oxygen here and one chlorine. So this is the chemical formula of this structure. Let's move on to this guy. 1, 2, 3, 4. Four carbons.
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Each one here has two bonds to a hydrogen. It means two, two, two. That's eight hydrogens, plus this one is nine. Total of nine hydrogens. So that's C4, H9, one oxygen, and then one hydrogen. C4, H9, O, N.
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What order? The order is typically C first, H second, oxygen next, and then anything else that comes out. All right. How about this guy over here? Let's be mindful. This is an end point. One carbon here, one carbon there, there.
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Each point here is a carbon. This is also a carbon. Right there. And the little stick here is a carbon right there. CH3 with it. So let's count. 1, 2, 3, 4, 5, 6, 7, 8, 9. C9 there.
33:21
And I count the number of hydrogen atoms. There's three here, two there, there's one there, two there, one there, three there, none here, none here, here is one, and here is one. That's total 16. Position of two oxygens. O2. So the formula here, C9, H16, oxygen 2.
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So this is really just being meticulous about it, and check yourself several times. And you'll be able to pull this off.
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Oh! There's one more here. This is a benzene kind of structure, as you can see. 1, 2, 3, 4, 5, 6 carbons. 1, 2, 3, 4, 5, 6 hydrogen and one oxygen. This is C6, H6, O.
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Oh! They get more and more interesting. But don't be discouraged, it's the same mechanism. 1, 2, 3, 4, 5, 6, 7, 8. C8. This corner point has 1, 2, 3, 4 bonds, so there's no H's there, no H's there.
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One here, one here, one here, one here. And one there, one there. So the C8, H6, one more. One hydrogen there, 2, 3, 4, 5, 6. All right. Something similar,
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but now with some nitrogen incorporated, you do the counting. 1, 2, 3, 4, 5, 6, 7 C7, H6, N2. Don't forget this H right there. It counts. You want to see the hydrogens?
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One here, 1, 2, 3, 4, 5, 6. All right! My goodness. Now here's a example from an exam from a couple of years back. I took an exam a couple of years back, and I just copied it correctly. And it's right here.
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Draw a line structure of the total and total line. And this is just to get you guys excited. All right? Let's see if we can do this. Now what the hell is this? 3.
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We have to know what if I selected this. CH3 is between parentheses, between them. Xy is one thing. And there's three of them. And those three things are going to be this problem right here. So this problem is a problem with one CH3 there, one CH3 there, and one CH3 there.
36:22
So I'll show you what it looks like. It looks like this. That is the carbon. That's the carbon. That's this one over here. CH3 right there, CH3 right there, CH3 right there. So this carbon is four bonds. There's no additional hydrogens.
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Then the CH2 unit right there. CH, CH, that's the unit that we recognize as a double bond between two carbons. The CH2 unit is just a corner point. And a Br. So this C here has two hydrogens and one Br. Okay? One bromine. This is not a carbon
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at this end. This is a bromine bond to this carbon. Okay? Okay, now an example from an exam. Give the molecular formula of the following line structure so now we have to recount it. Looks very similar to the previous slide. One, two, three, four, five, six, seven, eight, nine.
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Where did it start? Here? One, two, three, four, five, six, seven, eight, nine, ten. C10H8. One oxygen. Let me show you what the hydrogens are. Here?
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Not there! One, two, three, four, five, six, seven, eight. Yes? Why is there no hydrogen right there? Who knows? Yes, you. Yes, the carbon has four bonds. Let's count!
38:07
One, two, three, well, it's the different guy over here. Four. Four bonds, no extra hydrogen. Question? The H's? In this one here?
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One here, One there. Why is there one? Because this is a carbon with three bonds, the other one must be a hydrogen. One hydrogen, two, three, four, five, six, seven, eight. Those corner points do not have hydrogens, as we just discussed. Okay?
38:42
Now these things, these line structures, are absolutely ubiquitous in any form of chemistry you will be engaging in the rest of the law. Okay? So if you open a book and give them a set of rheology, chemistry, this is how you are going to take it. The structure is going to come right out of it,
39:04
only when you take it properly into two line structures. So you have to be able to work with these things. Okay, here's an example of why line structures are extremely important. These are some called pheromones, or beans. Two molecules that look alike. They look alike a lot, in fact.
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The only difference is the location- oops, somebody ordered the beans? This OH group shifts position only one spot. It goes from here to there. That's the difference. Very solid. Very solid. The chemical formula is almost the same.
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From the formula itself, you don't see any difference. You have to grow a line structure to appreciate the difference between these two molecules. This is the pheromone of the queen bee, the pheromone of the worker bee. Small changes in the molecular structure, majestic differences in ranking. The worker bee has to do very different kinds of things than the queen bee. So this is a beautiful example of subtle chemical differences that are depicted
40:06
in the line structure. Another example is this. This is a structure that you can extract from plants, particular plants. And there's nothing really
40:21
too special about it, but if you take this thing off, okay, and you oxidize it, you get this structure, small change, but dramatic differences in appearance. This thing here appears blue, this molecule is completely colorless. So the line structure nicely indicates where the changes took place. It can help to explain why this is a colorful molecule
40:44
and this one is not. It has to do with the number of double bonds that are, right? close to each other, that actually clarifies where something is very colorful and something else is not. This thing can now actually pull off another structure it takes one of its neighbors and bonds to it, produces a very interesting bridge, a double bond bridge, and
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this is called indigo. Beautiful blue that some people like to see on their faces. Another example of a line structure that actually the right way to depict a molecule, what? I'm sorry, man, this is going to be, you know, taking sides here. This is chemistry, okay? This is chemistry.
41:30
This is the molecule I'm talking about. I'm not talking about this guy. This guy took a lot of these things. That's the point. Okay? So this is testosterone. You see, it's a rather complex structure. In order to appreciate the
41:43
details of this molecule, you have to know what the molecule looks like. The line structure looks like. It helps you interpret that. You see another one, this is very close, you see there's also a steroid. But some small changes here define that this is a slightly differently behaving kind of molecule.
42:02
Another example this is also from the same family these are the, not the male version, but the female version of the same hormone. It's SRVR. And, you know, you can make things very nicely in the lab. And this is actually the component that is used in the field to prove to those bodies that they are
42:25
not receptive for all kinds of things. Okay? So now, interestingly, there are people that are looking for molecules that can do the same thing for men. Okay? So this is a structure, a beautiful line structure, that has apparently the effect of suppressing springtime.
42:49
In males. If you're interested in using this, let me know. All right. That's it.