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카테고리
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학습트랜스크립트
00:00:00Hello, in order to better understand our polymer lecture slides,
00:00:14I would like to go for this organic chemistry a little bit.
00:00:19I think this presentation covers most of the basic organic chemistry part,
00:00:26including that functional group.
00:00:29That is quite important to understand the characteristics of polymers,
00:00:34so I strongly recommend you go through this slide too,
00:00:39before you go for the polymer part.
00:00:46Okay, in this class, I would like to address what the organic molecules are.
00:00:53So here the main important words are like organic.
00:00:58You know, we use these words in our lifestyle many times.
00:01:03For example, the organic vegetable,
00:01:07which means a little bit different from what I'm going to explain in this class.
00:01:12You know, when we say organic vegetable or organic,
00:01:19what is that?
00:01:21Some lettuce or any kinds of vegetable kind.
00:01:26Then at that time, that organic means they didn't use any,
00:01:31some sort of side material.
00:01:35Some sort of side material means it's some bug killing,
00:01:40some organic spray or any like insect side.
00:01:47Insect side means the killing insect.
00:01:50It's not a medicine, but you know, what is it?
00:01:55It's some sort of bad chemical, right?
00:02:02Also, what are some of the common organic materials
00:02:06and how do they differ chemically?
00:02:09That's where the functional group covers.
00:02:13So we have many different kinds of organic material.
00:02:18Then what makes them unique,
00:02:21different from other kinds of organic material?
00:02:25So that's what we are going to see in brief way,
00:02:31not in detail.
00:02:32The polymers and their characteristics.
00:02:35That's what I'm going to explain.
00:02:38Okay.
00:02:39We will see a starting is like organic chemistry.
00:02:42This is, this slide is from like the,
00:02:45what is that?
00:02:46Like a general chemistry.
00:02:47So you may,
00:02:48had a,
00:02:49you may had,
00:02:50have had a chance to see this kind of,
00:02:53the organic chemistry related,
00:02:56related chapter in previous life.
00:02:59Undergraduate the class.
00:03:03So organic chemistry is the study of carbon compounds.
00:03:07This is not exactly correct.
00:03:11Because we have a lot of inorganic compound,
00:03:14which treats carbon too.
00:03:16For example,
00:03:17diamond and what else like some black carbon
00:03:22or any basic carbon material and soot,
00:03:28you know,
00:03:29like a soot related material.
00:03:32They are not organic compound.
00:03:33They are treated as inorganic compound.
00:03:36So,
00:03:37but this is also some,
00:03:40some part,
00:03:41in some part,
00:03:42it's correct.
00:03:43We will see what's the really,
00:03:45the nature of organic molecules.
00:03:47Carbon is a tetravalent.
00:03:49That's always true,
00:03:50I guess.
00:03:51So in diamond structure,
00:03:53or,
00:03:54in,
00:03:55in,
00:03:56in case of that,
00:03:57graphene,
00:03:59in,
00:04:00but still,
00:04:02like a tetravalent.
00:04:03Tetravalent means that tetra,
00:04:05valent is kind of like,
00:04:07what is that?
00:04:08Some sort of hands.
00:04:11Tetravalent means like,
00:04:12it has a four hands and grabbing something.
00:04:19So carbon has four hands.
00:04:22That's,
00:04:23that might be the way you can understand easily,
00:04:26or the characteristic of like a carbon bonds.
00:04:29It has a four outer shell electrons.
00:04:33Here,
00:04:34S orbital,
00:04:35P orbital.
00:04:36That's quite important.
00:04:37You know,
00:04:38the S orbital is shaped like,
00:04:40this circle,
00:04:41actually,
00:04:42it's a ball shape.
00:04:44Right?
00:04:45Ball.
00:04:46And then,
00:04:47P orbital is this way.
00:04:50This way,
00:04:51and this way.
00:04:52So,
00:04:53they are existing at x, y, z axis.
00:04:57x, y,
00:04:59I'm sorry,
00:05:00this is y,
00:05:01and z axis.
00:05:02x, y, z.
00:05:04So,
00:05:05here,
00:05:06I will give you some,
00:05:07I will ask a question.
00:05:09So,
00:05:10if we have some other,
00:05:12the atom to attach this ball,
00:05:17then,
00:05:18what's the,
00:05:19what's the best geometry for that ball?
00:05:23Let's say,
00:05:24I put one ball here,
00:05:25and the other ball goes to the opposite.
00:05:28Maybe,
00:05:29it doesn't have to be the opposite,
00:05:31but opposite way.
00:05:33And then,
00:05:34some other balls can go through between them,
00:05:37or,
00:05:38they can adjust their angles to minimize their energy.
00:05:41state.
00:05:42That's what we can guess.
00:05:44So,
00:05:45if,
00:05:46the,
00:05:47the atom is a ball shaped,
00:05:50the ball is the way we can connect other things together.
00:05:56Then,
00:05:57this angle can be anything.
00:06:00Let's say,
00:06:01I have 4,
00:06:026,
00:06:038,
00:06:0410,
00:06:05I can attach as many as the,
00:06:08the extra ball onto this,
00:06:10the,
00:06:11the,
00:06:12the,
00:06:13the surface of this ball,
00:06:14to make the bonds.
00:06:15That's the orbital,
00:06:16right?
00:06:17So,
00:06:18S orbital characteristic,
00:06:19S orbital,
00:06:20all angles are possible.
00:06:27Correct?
00:06:28How about P orbital?
00:06:31P orbital,
00:06:32they are existing at the axis.
00:06:36So,
00:06:37if I choose,
00:06:38x-axis,
00:06:39P orbital,
00:06:40and y-axis,
00:06:41P orbital,
00:06:42their angles are 90 degree.
00:06:46So,
00:06:47whatever I choose,
00:06:48x-axis,
00:06:49Z orbital,
00:06:50they are 90 degree,
00:06:51like they are perpendicular to each other.
00:06:55Or so on,
00:06:56right?
00:06:57So,
00:06:58P orbital,
00:06:5990 degree.
00:07:00I'm sorry,
00:07:01not degree,
00:07:02not Celsius.
00:07:0390 degree angle.
00:07:05So for S-ovital, all angles are available, but P-ovital, only 90 degrees are available for the connection.
00:07:17So keep that in your mind.
00:07:19But how about this methane?
00:07:21Do you think this angle is 90 degrees or any angles we can get?
00:07:27No, right?
00:07:29Do you remember what angle this is?
00:07:31That's 109.5 degrees.
00:07:35Why?
00:07:37That's not even in this class.
00:07:39S-ovital, maybe possibly this one, like all angles are.
00:07:44But you know, in S-ovital, we have two electrons.
00:07:50P-ovital, we have two electrons.
00:07:53So there are four electrons available to make bonds.
00:07:56That's why it says like a tetravalent.
00:08:00But actually, two electrons are in this S-ovital.
00:08:03And P-ovital is only two of this P-ovital.
00:08:07So one P-ovital is still empty, totally empty.
00:08:12That's what we see for carbon, right?
00:08:15So those two electrons in S-ovital, if they are working to make connections, then two bonds are like somewhere, wherever we can get.
00:08:28But the next two bonds must have a 90 degree angle because P-ovitals are that way, right?
00:08:42So, you know, the hydrogen has only one S-ovital.
00:08:47S-ovital can be attached onto P-ovital this way.
00:08:51That's what we learned in general chemistry.
00:08:54Or this, the hydrogen electron, one S-ovital may either in two S-ovital or carbon, and then one S-ovital in hydrogen, one S-ovital.
00:09:10It can go anywhere, but in P-ovital, the hydrogen, this is the one S and two P, or it goes here.
00:09:23So we expect 90 degree or any degree.
00:09:31But we see 109.5, which we cannot expect clearly from what we have learned at this slide.
00:09:42So that's a quick question I start from.
00:09:46Just keep that in mind to see what's happening in the next slides.
00:09:53Okay, organic molecules have covalent bonds.
00:09:56You know what kind of bonds we have in chemistry?
00:09:59Normally, there are many.
00:10:02For like metallic bonds, metallic bonds.
00:10:07And then also ionic bonds.
00:10:11Ionic bonds.
00:10:12And hydrogen bonds.
00:10:14But that's like a secondary van der Waals force, something.
00:10:19So the hydrogen bonds or something, they are like a secondary force bonding because they are weak.
00:10:27But mainly, like a metallic bond, ionic bond, and covalent bond.
00:10:31Those threes are the major bonds in chemical bonding.
00:10:36So in ethane, for instance, all bonds result from the sharing of two electrons.
00:10:44So the carbon has four tetravalent.
00:10:47That's what we saw.
00:10:48We saw in the previous slide.
00:10:49One, two, three, four, those four electrons are from the carbon.
00:10:56And then one, one, one, one, one, one, one, one, one, one, they are all from the hydrogen, right?
00:11:10So it's matching like a total eight electron.
00:11:14That's the octet rule, right?
00:11:16That's what we believe.
00:11:18So that's ethane, and this covalent bond, covalent bond too.
00:11:26So we draw this way or just this way.
00:11:30So when we have a line, every, like the angled line or the ending part is carbon.
00:11:40And since the carbon has four tetravalent, so we expect there might be three more connections.
00:11:51And if it's not given, then they are all hydrogen.
00:11:58So that's the way.
00:11:59So it's easy from starting.
00:12:03And then if we replace one of the hydrogen to chlorine or lithium, then we expect some polar covalent bonds.
00:12:14So in the case of chlorine, it has the higher electronegativity than carbon.
00:12:22So partially it's negative and it's partially positive.
00:12:26Or if we have a lithium compound, then lithium is the metal compound, metal elements.
00:12:35So metal normally has a positive value.
00:12:38So that should be positive.
00:12:40And carbon can be partially negative.
00:12:42So basically carbon can be negative part or positive part, depending on what kind of the elements are connected to the carbon.
00:12:55So, you know, these are quite important because the organic chemistry, there is a lot of the named reaction or some expanding or the new functional group chemicals.
00:13:17So in that case, they have to attach something or delete or detach something from the organic molecule.
00:13:26So how if we have regularly the non-polar covalent bonds, that's a little bit difficult to detach.
00:13:40But if we have this, like some, the charge distribution on one side, that might be easier to detach that part.
00:13:54Or if that becomes the ionic part, you know, in the case of ionic compound, if we control the ionic strength in the solvent, then we can dissolve it.
00:14:07And sometimes the ionic bond can be dissociated in that solution.
00:14:13So a lot of lithium compound is dissociated in the organic solvent to do some intercalation and de-intercalation chemistry for the battery application.
00:14:29And so as I mentioned before, if we have this dots model that can be replaced by this line one, one line represents two electrons.
00:14:43So multiple covalent bonds, so here are like two lines, that means one, two, three, four, four electrons are existing for that connection.
00:14:55And ethylene, ethylene is one of the important compounds in our life's life.
00:15:00Because, you know, in crude oil, if we find the crude oil in the basement, normally they have gas inside too.
00:15:12That's the ethylene.
00:15:14So the content of the ethylene, the amount of the ethylene is the key issue for the value of that mine.
00:15:25Because, you know, this ethylene, we will learn about the polymerization in the next presentation, also at the end of this slide too.
00:15:38So these four electrons can, because there are like extra electrons, two electrons are enough to make the connection.
00:15:52And then two extra electrons can be used to make bonds to the next ethylene.
00:15:59So if we do some environmental change, then ethylene can be used to make the polymers.
00:16:12And that polymer is the material we are using to make our clothes.
00:16:19You know, without this like crude oil chemistry, then what else we can do to get our clothes?
00:16:33So what's the way we can get our blanket or your jacket and underwear and also like shoes and bags and umbrellas?
00:16:54So look around, most of the compounds are fabricated by the polymer material and those polymers are prepared by this ethylene from the beginning.
00:17:10And also if we replace one of this hydrogen to like the benzene, that's polystyrene.
00:17:17And there are many different kinds of polymers, but they need this ethylene or acetylene as a starting material.
00:17:29So, you know, currently a lot of people are trying to replace this, the oil industry to some hydrogen industry or electricity
00:17:45and nuclear power or something to get energy, but if we have only that kind of energy, power, then how can we get our clothes?
00:18:02We need them, right?
00:18:03So maybe like a crude oil industry may, might be still, they may or they should continue to produce any products we need unless we use cotton, right?
00:18:26So, can we use this material to make everything or what else like we need a crocodile surface and the cow, what do they do after killing those animals to get food?
00:18:50But I don't know, that's, that's, that's not the way I'm going to go through.
00:18:58So here, I came finally here in this slide, organic molecules have a specific three-dimensional shapes and which can be predicted by VSEPR model.
00:19:09So it's model, so it's model, it's also, I think it's kind of the VSEPR, I think some textbook explains as a theory for the VSEPR, that's balanced shell electron pair repulsion.
00:19:27Now, electrons are negatively charged, so they might have a repulsion to each other.
00:19:33Now, but I, I mentioned that orbital, orbital is quite important for electron, the staying or electrons are moving around to make bonds, right?
00:19:50The orbital connections are actual bonding.
00:19:53But, you know, we can understand this one because it's obvious, there are one, two, three, four electrons from carbon and one, two, three, four electrons from hydrogen.
00:20:07But we just saw that like two electrons are from S orbital, that's also theory, right?
00:20:14And two electrons are from P orbital, but we don't see any 90 degree on this angle.
00:20:21Although we don't know this is the real structure for the methane in the real world.
00:20:27We, we haven't, uh, get any, like a real, the shape for methane, we didn't see that, right?
00:20:37So, uh, I don't know, actually they are really look, look like the carbon is here and then two hydrogens are connected this way.
00:20:48And then the two P orbital can be connected to like a 90 degree this way.
00:20:55And then, um, due to this electron, the balance shell electron pair repulsion, they might reorientate their shape.
00:21:12So, uh, whatever, actually, do you know what we are, uh, adopting to explain this?
00:21:24That's hybridization, right?
00:21:26SP3 hybridization.
00:21:28So, actually, they saying like S orbital and P orbital is a hybridized, they mixed all together, and then they reoriented to make this shape.
00:21:41So, S orbital is this way, P orbital is this way, or this way.
00:21:47And then they are all mixed up, and then that's hybridized, so there is no S orbital anymore, any longer, because, uh, they mixed up.
00:21:58And then, SP3 orbitals are newly, uh, the, generated, S orbital, P orbital, and, uh, S orbital mixture, and then S orbital, P orbital, and, uh, somehow.
00:22:14But that's like a tetragonal to each other.
00:22:19I'm not good at drawing, but that's the way, this way, okay?
00:22:23So, the other small, the, uh, orbitals are, uh, hidden behind it.
00:22:32Can you believe this?
00:22:34Do you think they, uh, the, the nature is doing some sort of mathematical way, and then figure out this way?
00:22:45I don't think so, right?
00:22:47So, um, I, I, I really don't know what's happening there, because the nature does not require any, uh, math or computation to determine their, their, um, shape.
00:23:03They just stayed as they wanted, or not they wanted, but they, they stay as they are.
00:23:12And then, to understand them, we made a lot of theory.
00:23:16And then, one of the theory is, uh, this, uh, SP3 hybridization.
00:23:21That's our way to explain this.
00:23:24So, we can, uh, accept this one, and then apply this to any other, uh, organic molecule.
00:23:33And then, maybe, if, if we see any, like, a critical error, then we have to replace or modify that, uh, the model.
00:23:44But, so far, we, we can understand, uh, most of the organic compounds in, in correct way.
00:23:54So, we still accept, um, this hybridization for some sort of mathematics.
00:24:01But, I don't think nature have done that mathematics to, uh, show their, uh, shape.
00:24:11But, anyway, nature, let's go, uh, let's go, uh, let's keep moving.
00:24:14So, in the case of this, the double bonds for carbon, and then, there are only three sets of the electron, the, in the outer, uh, the, this carbon.
00:24:27But, in the case, in this case, what if we believe this, the four electrons are stronger, and two electrons are weaker.
00:24:37Then, this force is bigger than this force.
00:24:41So, they may, like, uh, push the other way.
00:24:46And then, um, this angle might be a little bit greater than this angle.
00:24:54That's what we can guess.
00:24:56But, somehow, they show only, like, a hundred and twenty degrees angles.
00:25:01Why?
00:25:02I don't know, but the, the textbook does not go detail.
00:25:09Maybe the electrons are sharing in between them.
00:25:12So, actually, this model, like, drawing, may not give us the complete understanding for this organic molecule.
00:25:21But, that's not the way we go through, because our class is not the, uh, the class over the nature in organic chemistry.
00:25:36We just understand the materials, the, uh, the characteristic.
00:25:41Then, the, how we can apply that one to, uh, our purpose.
00:25:47Um, but in this case, it, this can be understanding, understood by, uh, the, the BSDPR model.
00:25:56Because, uh, although it has, like, uh, six electrons inside.
00:26:01So, this power might be greater than, um, watt.
00:26:07Because, uh, this, this is the, this way, this way, it's evenly pressing.
00:26:13Right?
00:26:14So, there is no, like, um, the comparative force.
00:26:18Like, here, in this, uh, in this case, this force is the, competing with this force.
00:26:28But, in this case, they are even.
00:26:32So, uh, they cannot compete.
00:26:35So, it's, like, 180 degree angles.
00:26:39VSEPR model.
00:26:41Okay.
00:26:42So, um, SP3 hybridized.
00:26:45SP2 hybridized.
00:26:47SP hybridized.
00:26:49So, without it, S overall, we expect only 90 degree.
00:26:54Or, SP2, one S overall.
00:26:57And then, two P overall.
00:26:59So, still 90 degree.
00:27:01And SP hybridized.
00:27:02So, S overall, that's okay.
00:27:04But, P overall, it's 90 degree.
00:27:06But, somehow, it goes this way.
00:27:13Uh, if we have only single bond along this carbon chain, we, uh, say that, we place those,
00:27:25the organic compound in alkane compound, alkane.
00:27:30And then, uh, there are some isomers.
00:27:34With the same number of carbon and hydrogen, we can, uh, make different kind of the connections.
00:27:42We will see that in, uh, soon.
00:27:46Here, this is methane.
00:27:48And ethane.
00:27:49And propane.
00:27:51The hydrocarbon that contains only single bonds.
00:27:56Since this, like, carbon hydrogen bonds are always a single bond.
00:28:01Because hydrogen is only one electron.
00:28:04It cannot make double bonds at all.
00:28:08So, uh, if we have only carbon and hydrogen elements for that material, then they are always
00:28:16alkane compound.
00:28:18And then, uh, depending on the number of the carbon, then we say like a methane, ethane,
00:28:27propane, butane, pentane, hexane, or something.
00:28:32It goes that way.
00:28:34And then, see, uh, if we have a, see, uh, four carbon and 10 hydrogen, it can be this way.
00:28:42They are all linearly connected.
00:28:45Or, the, one of the carbon can attach to the central carbon, this way.
00:28:52That's called like a branch point.
00:28:56So, in the case of a pentane, pentane's, uh, uh, normally this one.
00:29:03But, if we have one carbon in, um, uh, branch here, or many branches in the central carbon.
00:29:14So, they are all different.
00:29:16Uh, they are showing different characteristics.
00:29:20Different boiling point, different melting point, and, um, sometimes, uh, toxicity, too.
00:29:31So, they are isomers.
00:29:34Isomers.
00:29:35Isomers.
00:29:36Isomers.
00:29:39The same number of carbon, the same number of hydrogen, but different geometry.
00:29:45That's isomers.
00:29:48Okay, uh, then I, and if we have the, some oxygen, that's also like a, some alkane compound,
00:30:00basically.
00:30:01But, if we have this, uh, uh, uh, alcohol compound, that's something oil.
00:30:09So, here, that's ethane, ethane oil, ethanol.
00:30:15Or, uh, oxygen can be the, going in, uh, in between carbon, then that's ether.
00:30:25It's, um, normally, this one doesn't smell much, but ether is, uh, giving quite, um, annoying smell.
00:30:38You know, it's like some medical compound, or, um, you know, it's, uh, it's toxic.
00:30:51You, whenever you, right away you, you smell this one, you will figure out, oh, it's, uh, you want to, like, throw it up something.
00:31:03So, um, they are isomers, and totally different characteristics.
00:31:10This is volatile, volatile, but this is not.
00:31:16Like, boiling point is around, like, what, what, what, what's, like, 72 or 78, around here.
00:31:23But this one is quite volatile, it means it, it wants to go evaporate, evaporate very soon.
00:31:34And then, also, like, uh, butane, uh, and also, to methylpropane.
00:31:42You know, uh, the number of the carbons are the same for this, one, two, three, four, one, two, three, four.
00:31:49But main, uh, axis distance has, like, four carbons, but here it has only three carbons.
00:31:56This way three carbon, and this way three carbon, so it's not butane any longer.
00:32:02It's propane, two methylpropane.
00:32:06We are not going, uh, go through the, the, the, with nomenclature, the naming.
00:32:12Well, I will explain just briefly for, uh, our, the focus.
00:32:21Uh, the shape.
00:32:24So, we already saw that most of the carbon compound has, like, a tetrahedral shape.
00:32:30So, the carbon, one, two, three, four, they are, like, a 109, uh, five.
00:32:38So, this 109, 109, they are all, uh, showing that way.
00:32:44So, it's not that, uh, much difficult to understand your geometry.
00:32:50And also, like, uh, methane, ethane, propane, something, something, uh, haptane, octane, no name, uh, decane.
00:32:59You know, the word, you know the word, like, a decade.
00:33:02That's 10 years, right?
00:33:04So, decane.
00:33:06So, you already know that.
00:33:09No name.
00:33:11Nano, right?
00:33:13Nano, something, 10 to the 9th.
00:33:16Nine, similar to red.
00:33:19Octopus.
00:33:20Octopus.
00:33:21Octopus.
00:33:22Octopus.
00:33:23Octopus is 10th, 10th, the month.
00:33:26But actually, it's meaning 8th, right?
00:33:29Uh, there are many stories, uh, to explain why Octopus is 10th month instead of 8th month.
00:33:37So, fiscal year starts in March.
00:33:40So, if we count that from the March, October is the 8th month.
00:33:46Because who determined that January is the first month of the year?
00:33:53Maybe in old age, maybe March is the first year for their counting.
00:34:02And also there is another way.
00:34:04So actually October was the eighth month in a whole year.
00:34:11But Julius Caesar and Augustinus, they wanted to add their name into the month.
00:34:19So they replaced some months and then they put it into whatever they want.
00:34:26So July entered between June and August and August was also added that way following July.
00:34:40I don't know if that's true or not.
00:34:41But you know, octet rule is like 8 electron rule, not 10 electron rule, right?
00:34:48So that might be the way you can see.
00:34:52So naming alkane is the longest chain that I will just go through very quickly too.
00:34:59Because we don't care much about the naming itself.
00:35:03But for a better understanding, this is also quite important too, right?
00:35:09And see, if we have some branch, then earlier number must be given to that carbon.
00:35:15So 1, 2, 3, 4 is correct one, but 1, 2, 3, 4 the other way is wrong numbering.
00:35:22So if we have some functional group or any branch, any branch should have the earliest number.
00:35:31The first one, we don't care.
00:35:34Let's say the other one comes to here.
00:35:39But if we go 1, 2, 3, 4, 5, 6, then the functional group comes 3 and 6.
00:35:45But if we go the other way, 1, 2, 3, 4, then the first numbering comes to 1 and then the other
00:35:53one comes to 6.
00:35:55So 3, 6, 1, 4, which one is faster?
00:36:00So 1, 4 is faster.
00:36:02So depending on the functional group, then we give different numbering.
00:36:10If we have alcohol functional group, the whole naming can be changed, some sort of alcohol.
00:36:20So in that case, this should go to the end, I'm sorry, but I just show this one for an
00:36:27example.
00:36:28So in the case of alcohol, it doesn't matter where this methyl compound is.
00:36:36And alcohol is the name, so it goes this way.
00:36:43And then identify the one, and then the methyl group can be removed, and then we attach it
00:36:54to methane.
00:36:56If we remove that one, so this is methane, but if that is attached to something, that is
00:37:03connected this way, so that's methyl, or ethyl becomes ethyl.
00:37:10For example, that's methyl something, ethyl, methyl something, methyl, methyl, and this is the
00:37:20long chain, see, like dimethyl.
00:37:26And then if we have like a CS3 material, that's propyl.
00:37:32And then if it's like a centred carbon, that's isopropyl.
00:37:36And butyl, secondary butyl, isobutane, isobutyl, and tertiary butyl, there are many different
00:37:43kinds of shapes.
00:37:47And then cyclo-alcane, I will just skip that part.
00:37:53And just try to name one of them for fun, I guess.
00:38:03And the reaction of alcanes, that's also important.
00:38:07So this is the combustion reaction, so this is the most basic equation, the reaction equation.
00:38:18So all the carbon becomes carbon dioxide, and the hydrogen goes to the water form.
00:38:24But I mentioned that this methane is a starting material, or ethane, or ethylene, whatever.
00:38:31And that organic compounds must be replaced by some other functional group to synthesize
00:38:38the high-quality chemicals, or the high-functional chemicals, including medicine, or fertilizer,
00:38:48and any like a strong polymer material, whatever.
00:38:55Normally we give high energy, you know, one electron volt is equivalent around like 10,000
00:39:04K, right?
00:39:06So that's quite high energy, like a photon has a very high energy to dissociate something,
00:39:14or induce any chemical bonding.
00:39:19So if we give this like a high light energy, then that dissociates that carbon hydrogen bond
00:39:27and replace one of the hydrogen to chlorine, and then if we do that further, like chlorine
00:39:34with H mu again, H mu again, then just keep going into that.
00:39:42So we finally, we see like a tetrachlorocabon, then what can be changed through all this chemical
00:39:52reaction?
00:39:54This was a gas, but this is not.
00:40:01And this is not either, and this one has a, this is also a little bit volatile, because
00:40:07that's the some sort of frown gas, right?
00:40:12So if they are released to the air, they like, they are quite light, so they go up and up, up
00:40:20to the atmosphere, and then do some bad effect to our, the earth environment.
00:40:30So we should be very careful to synthesize this kind of chemical.
00:40:35We didn't know that much about our, the earth chemistry before, but now we understand a lot
00:40:41of things.
00:40:43So we are doing quite the, we are doing very careful work for saving the our, the earth for
00:40:56the next generation.
00:41:00So families of organic molecules, functional group, that's what the, I wanted to focus.
00:41:07The functional groups are like an atom or group of atoms within a molecule that has a characteristic
00:41:15chemical behavior, and that undergoes the same kinds of reaction in every molecule where
00:41:21it occurs.
00:41:22For example, we just saw like a carbon and hydrogen, that's not functional group.
00:41:28But once we have this chlorine inside, that's functional group.
00:41:34So it says like a same kinds of reaction.
00:41:37This one can be easily replaced by any hydroxyl group by like a water molecule, then that becomes
00:41:46methanol.
00:41:51And then if we have a two carbon and one of the chlorine is attached, then we also do the
00:41:59same kind of reaction, and that can be replaced by hydroxyl group, and that's ethanol.
00:42:08So same kinds of reaction, but not always go this way, because sometimes that the, if we
00:42:15have a longer carbon chain, that's not a liquid form, that's like a solid form.
00:42:22And if we, that chain is longer, then that chain can be the covering this hydroxyl group, and
00:42:30hydroxyl group goes to the inside of the molecule, then it's very, it's not easy to make the reaction
00:42:38of this hydroxyl group to replace that into some other things or whatever, or chlorine.
00:42:49So same kinds of reaction, not always the same reaction.
00:42:53So they didn't say like the same reaction, the same kinds of reaction.
00:43:01Double bond is also some kind of a functional group, alkyn.
00:43:09I already mentioned that here are like four electrons, see like a higher electron density
00:43:15around this carbon, then higher electron density means the, it's like a relatively high, the
00:43:26negative charge the inside, but the whole balance can, cannot be treated that way.
00:43:32But locally, like high electron, and then if we have some high energy, like H mu with bromine,
00:43:42then that can be disconnected to make this bromine addition reaction.
00:43:50So, you know, in the previous slides, we learned that if we have the energy with the chlorine or something,
00:43:58that goes to this side, right? But once we have this double bonds or triple bonds, this is easier to
00:44:08disconnect compared to this carbon hydrogen bond. So now we may not need like a high energy
00:44:17to add this bromine. That might be why they didn't put this on the, uh, the light here.
00:44:26Oh yeah. Right. I remember this like a bromine. Bromine color is, uh, what is it? Like brown color, right?
00:44:34So this occurs very regularly. It's, it's this, what is that? Um, um, very quickly, spontaneously.
00:44:43So if we add a small amount of brown, the brom liquid into this ethylene compound,
00:44:53then this, uh, the brown compound goes away because this brom, um, make the reaction with this,
00:45:01the arcane compound, and then they goes this way. It's still a transparent compound. It's,
00:45:07it doesn't have any color. So, um, uh, once we gave like a, this brom, brom is also quite volatile, volatile.
00:45:19So, uh, the, it's, it's like a gaseous one. So we can see small, like a brown color, like a smoke
00:45:28at the very beginning, but, uh, uh, in, and the, in some time that brown color go away disappear
00:45:38because they made all the reaction to this double bonds. I'm sorry for this, the wrong information
00:45:44about the, and the light addition. And then see here, there are many different kinds of functional
00:45:52groups here. Uh, I can, I kin, or I kind, and also the, um, what is that? The, this is the conjugated form,
00:46:03right? The, if we have double bond, single bond, double bond, single bond, double bond, single bond,
00:46:08then they have a piogra, the, I'm sorry. They are all like, uh, sharing this on the empty, the piogra,
00:46:19that makes, uh, some sort of conjugation. And also here, uh, alcohol, and then ether, that what we observed
00:46:30in the previous slides, and, uh, the ethane, see, this is also considered as a functional group,
00:46:37and triple bonds, and then benzene, and, uh, methanol, and ether.
00:46:48Um, you can guess the name of this one. Just practice that later.
00:46:56So, I kin, I kind, and that's unsaturated one. So, carbon can be, uh, carbon has like a four
00:47:04hydrogen, and then one is connected to carbon or hydrogen. So, they used all the electrons to make the bonds.
00:47:12But in, if we have a double bond here, they are sharing these electrons between this carbon,
00:47:18and that, that's not saturated because, uh, there's still the available site to add, I'm sorry, the more
00:47:26hydrogen. So, that's, that's, uh, unsaturated. So, uh, you know, when we do some food chemistry,
00:47:35some unsaturated one has like, uh, the, this, the double bond, right?
00:47:45And, uh, I can, as we saw, uh, there's an electron density
00:47:52inside. That can be, uh, used for the promenation,
00:47:58something. And then, uh, the, uh, I can, uh, and isomers are also available,
00:48:04depending on where that, uh, and the, uh, the double bond exists. So, it can stay here, or here,
00:48:12here, here, it can move, um, any, uh, the internal chain. So, they are like isomers.
00:48:21And, uh, alkenes, and then isomers, there are many different kinds of isomers. See,
00:48:29here, scyth, they are at the same, uh, the side, but if, if it goes to the other side, that's called
00:48:39like trance. I, uh, I think I removed some of the slides, but somehow, uh, it's, they stay here.
00:48:51So, I'm sorry, I will just pass by a little bit. Alkens and, uh, alkens, the alkens and isomers,
00:48:59then, uh, you know, like, uh, the, the, the pi bonds, the orbital overlaps, and then broken bond,
00:49:16no p-orbital overlaps. The, you know, the, that's like, uh, uh, that what I said, like conjugated.
00:49:24They are on the same plane, but if they are broken, so it's sp3, it's sp2.
00:49:38So, they are not, uh, they are, like, the, uh, overlap is not existing for sp3,
00:49:46but the sp2 puberals are overlapping. Then alkyne, uh, triple bonds. Almost the same way as we, uh,
00:50:00learned in the, the double bonds. So, the same way, the same, the, what is that, like isomers,
00:50:07alkens. And then also, like, uh, the bromine or any kinds of the, the halogen compounds can be, uh,
00:50:18added to this compound. Even, like, hydrogen can be added to this material with, like, catalyst,
00:50:26pladium or platinum, too.
00:50:28So, see, like, chlorine can be easily added. If we do this reaction, well, maybe we don't need
00:50:40this light, but, you know, in the previous slide, we, um, we had, uh, the methane, and then,
00:50:49if we have chlorine, then we need, uh, the mu light to make a CH3 shell or adding them further.
00:50:58And water can be added, too. See, that's like, uh, uh, what is that, alcohol fabrication.
00:51:07So, here's sulfuric acid catalyst. You know, this is also quite important because, uh, if we have,
00:51:15uh, like, a higher concentration of a sulfuric acid, then the other way reaction occurs. That's, um,
00:51:23removing water reaction because this sulfuric acid is high. If that has a high concentration,
00:51:30that it wants to lower the concentration by taking water out of this ethanol,
00:51:37and then that generates ethylene. So, uh, if we can use this strong, the, the highly
00:51:45toxic sulfuric acid concentration, then making ethylene, ethylene might be easier from this ethanol
00:51:54compound. Then, uh, that may give us some hint, like, uh, uh, you know, alcohol is, uh, I don't know
00:52:04what's the, the, the production yield, but when we go to the liquor company, they are making a lot of
00:52:11alcohol by, uh, uh, doing some, some chemistry work without any crude oil, maybe compound, right?
00:52:22From any rice or any kinds of grains, they make the alcohol. No, in old ages, the monkeys can make some,
00:52:32the liquor from the banana. And, uh, I remember that, what is that, chimase, that the, that is also, like,
00:52:47some enzyme catalyst to synthesize the, uh, this kind of ethanol. Once we have ethanol,
00:52:54then we can have this, uh, this strong, the sulfuric acid, then it goes, it releases this ethylene
00:53:04to the air. Then if we collect them, yeah, that, that case, we can get some, uh, ethylene compound to
00:53:13fabricate our clothes, but that might be very small amount. You know, the, if we have, like, uh, the apples,
00:53:20then keep it in some, uh, store, uh, place, then close it, then the, the apple releases more amount of
00:53:30the ethylene too. You know, the, if the, some of the, the fruit is not well, uh, ripen, then we add
00:53:40this apple to, uh, uh, overcook that apple, uh, overcook the, the other fruit. Uh, aromatic compound,
00:53:50that's the benzene, or, you know, I mentioned that if we have this, uh, ethylene compound with
00:53:56benzene, that's styrene, and if we make polymer with this one, that's polystyrene. And, uh, when benzene
00:54:04is, uh, added to the sun compound, it has a lot of, like, a strong scent. So that's why it says, like,
00:54:11uh, aroma. Aroma is, uh, kind of scent, right? I, but normally we say, like, aroma, that's nice smell,
00:54:22but the benzene smell is, like, terrible. If you smell that for a while, maybe you lose your, um,
00:54:29sane, I guess. You know, naphthalene, we use that chemical, uh, in our closet to kill all the,
00:54:39the box inside when I was young, but I don't think they use it. And, um, but currently I, I saw many,
00:54:46like, the companies are still selling those ones, but they control the, the, the concentration.
00:54:52Okay, uh, and then the, uh, they are, like, conjugated the same way. Uh, that's, like, conjugation,
00:55:03resonance structure. And, uh, the, the reaction, the easily replaced by hydrogen, and that's a
00:55:14substitution reaction. I'm not going to go through for the substitution reaction or, uh, elimination
00:55:21reaction. But that's, like, a high quality organic chemistry. But once we have this, the functional
00:55:28group on this, like, benzene or whatever, then that can be used to initiate any, the further chemistry
00:55:38to attach something or replace something. So, you know, in organic chemistry, most likely the methane
00:55:48compound or organic, this, like, aromatic compound can be changed to this, like, a chlorine or halogen
00:55:59compound on it. And then that's the starting material to, uh, do some sort of, uh, chemistry.
00:56:09And then we see, like, many things. See, like, a starting point has only this small one, but see, like,
00:56:16uh, what is that, diazepam or valium? What are they? So, um, it can be, like, some medicine or, uh, insecticide, whatever.
00:56:28You know, alcohol, that is, like, a water functional group, carbon alcohol. And, uh, you know,
00:56:36ethane was a gas in one atm and the normal temperature. But ethanol is a liquid. So, uh,
00:56:45if we have this hydroxyl functional group, they are making some hydrogen bond between themselves.
00:56:52So, that connects all the, the material together.
00:56:59And then alcohol, see, like, that hydrogen bond.
00:57:04And the alcohol is the naming way. I mentioned that, like, when we have alcohol,
00:57:10that carbon has number one. We do not go one, two, three at all. So, this is the only way.
00:57:17But if alcohol is in the center, then, uh, we have to give, like, earliest number four,
00:57:24that alcohol functional group. Okay? One, two, three. If we have one more with CH3,
00:57:29then that should be one, two, three, four, not one, two, three, four.
00:57:38Uh, here, like, methane. I'm sorry, like, uh, the carbon monoxide with, uh, like, hydrogen
00:57:46and then some catalyst with, like, high temperature. It makes, like, methanol. And also glucose. See,
00:57:54that yeast, if we have yeast, then, uh, the carbon dioxide with ethanol. That's an interesting one,
00:58:07right? You know, this is gas. Gas, uh, makes the liquid. This is quite difficult. But this is liquid.
00:58:22And this is gas. This reaction is much easier. You know why? That's entropy.
00:58:32Entropy one. You know, gas has a high entropy. But liquid has a low in entropy.
00:58:41High entropy reaction is much easier. That's nature going this direction, right?
00:58:47So, um, when we need to design some sort of the chemical reaction, we also need to
00:58:57consider that one. If we have, like, higher entropy changes, that's not easy to make the reaction. So,
00:59:05we can control that entropy change is small. And, um, and then, uh, a few steps further
00:59:13to make, uh, like, small entropy changes. Okay. Uh, some, uh, important alcohols. The propanol.
00:59:25You know, the ethanol is the main compound for our, uh, liquor industry. But sometimes, uh, the propanol is,
00:59:34can be added to, uh, uh, can be added to, uh, uh, that one. Because, uh, you know, the,
00:59:40the liquor is not made by just exact, the chemistry comes with the reaction.
00:59:46You know, like, we do some grain, uh, as a starting material. Then they might have some, some, some,
00:59:54uh, some different molecules inside. They generate another types of alcohol. Uh, that could be propanol.
01:00:04So ethanol is, uh, also not that, uh, healthy food for our body that can make some, uh, what is that,
01:00:13like a headache. That's ham-over, right? Uh, but this one, propanol, it's like, um,
01:00:22um, much stronger than the ethanol compound for hangover symptoms. Normally, like, uh, in the wine,
01:00:35the, or, uh, you know, like that soju. Soju only has, like, the ethanol. It doesn't have any propanol
01:00:46or some sort of other kinds of ethanol or the alcohol compound, but wine or makgeolli and those
01:00:54liqueur, the prepared by grains or fruits. They all, they sometimes have this propanol inside.
01:01:05So the, you know, if somebody has, like, hangover on the next day of the, the drinking alcohol
01:01:12and a severe one that might be due to this wine or some grain-based liqueur.
01:01:25Okay, some, uh, important alcohols here too, but let me skip up a few. Ether, um, ether,
01:01:33we do not care much about this ether, but one of the big compound, the carbon, carbon, and oxygen,
01:01:40carbon, carbon, carbon, carbon, oxygen. That's, um, the, uh,
01:01:49PEC, polyethylene glycol. That's, uh, actually CCO. This is, was the beginning compound.
01:02:00And then they, uh, maybe it's this one too? No, one, two, three. It doesn't have, like, this one. And then
01:02:12really bond breaking here. They are making, uh, so it's, it also says, like, polyethylene oxide,
01:02:21polyethylene oxide or polyethylene glycol, whatever. Um,
01:02:26um, this is quite important, uh, the material because, um, it, it has, uh, some repulsion characteristics to
01:02:36the, the, the proteins. You know, like, uh, the human being protein industry is, uh, is getting
01:02:44bigger and bigger due to that, uh, the health one. But if that, uh, the, the protein is quite sticky,
01:02:52but if that protein goes everywhere, then that's quite difficult to control the, the analysis tools.
01:03:04So if we cover with this polyethylene glycol on top of that material, normally that the protein does not
01:03:13come to the surface. So this is a very important one. Other than that, I don't see this ether compounds
01:03:22for, uh, uh, the big industry much. But there might be something. So you figure it out.
01:03:31Okay. Uh, the, I will explain this, I'm in compound or related one to the next recording. Thank you.
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