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×ÖÄ» 00:00:26 PROFESSOR: Welcome to 5.111,
×ÖÄ» and today what we're going to
×ÖÄ» 00:00:28 do is introduce you to the course and the people
×ÖÄ» 00:00:30 teaching the course.
×ÖÄ» 00:00:34 And we're also
×ÖÄ» going to let you know that you were going to be
×ÖÄ» 00:00:39 part of the great
×ÖÄ» web exercise that is OCW, OpenCourseWare.
×ÖÄ» 00:00:43 So, this course is being videotaped this year, and
×ÖÄ» 00:00:46 this is the announcement that I have to make.
×ÖÄ» 00:00:52 So, the videotape is in the back,
×ÖÄ» and if you want to come
×ÖÄ» 00:00:55 up front and
×ÖÄ» participate in the class, you know that you'll be
×ÖÄ» 00:00:59 videotaped -- if
×ÖÄ» you want to hide your face or whatever, you
×ÖÄ» 00:01:01 can do that but please pay attention to the
×ÖÄ» 00:01:02 lectures anyway.
×ÖÄ» 00:01:07 So, this course will be available on the OCW site
×ÖÄ» 00:01:09 in the future, I'm not sure exactly what that
×ÖÄ» 00:01:13 date is going to be.
×ÖÄ» 00:01:15 So, today we're going to introduce the chemistry topics,
×ÖÄ» 00:01:18 which we will cover in 5.111, and give you general
×ÖÄ» 00:01:21 information, practical information about the course
×ÖÄ» 00:01:23 number of points you need,
×ÖÄ» when the exams are, that kind of
×ÖÄ» 00:01:27 thing, policies,
×ÖÄ» and introduce you to the teaching staff.
×ÖÄ» 00:01:29 I am, again, Professor Cathy Drennan, and I'm one of the
×ÖÄ» 00:01:32 lecturers in this course.
×ÖÄ» 00:01:36 So, because this is MIT, we're going to start to quiz.
×ÖÄ» 00:01:39 OK, not a quiz for points or anything, don't freak out,
×ÖÄ» 00:01:50 but I do want you to tell me who these people are.
×ÖÄ» 00:01:54 So, what about this person?
×ÖÄ» 00:01:59 That's me -- this is my college yearbook photo.
×ÖÄ» 00:02:01 OK, what about this person over here?
×ÖÄ» 00:02:06 STUDENT: You?
×ÖÄ» 00:02:09 PROFESSOR: It's not me again.
×ÖÄ» 00:02:12 Not Elizabeth Taylor.
×ÖÄ» 00:02:23 It is Lisa Kudrow, known as Phoebe on "Friends." So, we
×ÖÄ» 00:02:26 both went to college at the same time, we went to
×ÖÄ» 00:02:27 the same college.
×ÖÄ» 00:02:33 Does anybody know what college that was?
×ÖÄ» 00:02:33 STUDENT: Vassar.
×ÖÄ» 00:02:35 PROFESSOR: Vassar College, very good.
×ÖÄ» 00:02:39 And we graduated
×ÖÄ» the same year -- now no one has to say what
×ÖÄ» 00:02:42 year that was, even if you know, but we did
×ÖÄ» 00:02:44 graduate the same year.
×ÖÄ» 00:02:45 All right.
×ÖÄ» 00:02:51 So, given what you know about us, what do you think Lisa
×ÖÄ» 00:02:53 went to college to study?
×ÖÄ» 00:02:56 STUDENT: Computer?
×ÖÄ» 00:02:58 PROFESSOR: Computers?
×ÖÄ» 00:02:59 No.
×ÖÄ» 00:03:00 STUDENT: Theatre?
×ÖÄ» 00:03:00 PROFESSOR: Theatre?
×ÖÄ» 00:03:01 Surprisingly, no.
×ÖÄ» 00:03:02 STUDENT: Nuclear Engineering?
×ÖÄ» 00:03:04 PROFESSOR: Nuclear Engineering at Vassar, no for a
×ÖÄ» 00:03:08 variety of reasons.
×ÖÄ» 00:03:08 Any other guesses?
×ÖÄ» 00:03:11 STUDENT: English?
×ÖÄ» 00:03:11 PROFESSOR: English, no.
×ÖÄ» 00:03:15 Biology -- I heard it.
×ÖÄ» 00:03:16 Biology.
×ÖÄ» 00:03:19 What do you think I went to college to study?
×ÖÄ» 00:03:21 STUDENT: Theatre.
×ÖÄ» 00:03:24 PROFESSOR: Theatre, correct!
×ÖÄ» 00:03:28 And/or I hadn't made up my mind exactly --
×ÖÄ» 00:03:31 biopsychology or drama.
×ÖÄ» 00:03:33 So, biopsychology was what they called sort of brain and
×ÖÄ» 00:03:36 cognitive sciences in those days.
×ÖÄ» 00:03:40 So, those were the two things I was thinking about.
×ÖÄ» 00:03:44 What do you think Lisa ended up majoring in college?
×ÖÄ» 00:03:46 STUDENT: Biopsychology.
×ÖÄ» 00:03:50 PROFESSOR: Not biopsychology.
×ÖÄ» 00:03:50 STUDENT: Biology.
×ÖÄ» 00:03:57 PROFESSOR: Biology, yes.
×ÖÄ» 00:03:59 What do you think I majored in college?
×ÖÄ» 00:04:00 This should be a bit easier.
×ÖÄ» 00:04:01 STUDENT: Chemistry.
×ÖÄ» 00:04:05 PROFESSOR: Chemistry, And, of course, our professions,
×ÖÄ» 00:04:09 actress and chemistry professor.
×ÖÄ» 00:04:15 So, let me ask what happened here?
×ÖÄ» 00:04:19 My understanding about Lisa Kudrow is that she came
×ÖÄ» 00:04:20 from a Hollywood family.
×ÖÄ» 00:04:23 She went to college
×ÖÄ» and said here's my opportunity to study
×ÖÄ» 00:04:26 the thing that I find most interesting, and that was
×ÖÄ» 00:04:29 biology, and then
×ÖÄ» she went back and participated in the family
×ÖÄ» 00:04:33 business, which was of course the acting profession.
×ÖÄ» 00:04:35 For me, what happened?
×ÖÄ» 00:04:42 Well, I have to say,
×ÖÄ» I did not like chemistry in high school,
×ÖÄ» 00:04:45 so I did not think
×ÖÄ» about going to college to study chemistry.
×ÖÄ» 00:04:50 So, why did I not like chemistry in high school?
×ÖÄ» 00:04:56 I think it was because of images such as this one.
×ÖÄ» 00:04:59 You spend a lot
×ÖÄ» of time talking about the transition between
×ÖÄ» 00:05:00 alchemy and modern chemistry.
×ÖÄ» 00:05:03 I wasn't very
×ÖÄ» interested in that kind of thing, and there's
×ÖÄ» 00:05:06 nothing in these photographs that really appealed
×ÖÄ» 05: 00:05:07 to me personally.
×ÖÄ» 05: 00:05:12 I mean,
×ÖÄ» Avogadro -- I'm fond of his number, and he is, in
×ÖÄ» 05: 00:05:18 fact, an interesting,
×ÖÄ» if not frightening looking man -- this
×ÖÄ» 05: 00:05:21 just didn't connect with me.
×ÖÄ» 05: 00:05:23 But then I got
×ÖÄ» to college and they said, "Well, if you're
×ÖÄ» 05: 00:05:26 thinking about
×ÖÄ» anything bio -- biopsychology, biology -- you
×ÖÄ» 05: 00:05:31 have to take chemistry."
×ÖÄ» And I said to my advisor, "No, no.
×ÖÄ» 05: 00:05:35 I have taken
×ÖÄ» chemistry in high school, and I can assure you
×ÖÄ» 05: 00:05:38 that chemistry
×ÖÄ» has no relevance whatsoever to the life
×ÖÄ» 05: 00:05:42 sciences." And they said,
×ÖÄ» "Well, I'm sorry you feel that
×ÖÄ» 05: 00:05:46 way, it's incorrect,
×ÖÄ» and you have to take it anyway."
×ÖÄ» 05: 00:05:51 So, I, like some
×ÖÄ» of you in this room, took freshman chemistry,
×ÖÄ» 05: 00:05:54 because we had to, not because we wanted to.
×ÖÄ» 05: 00:05:58 And I, like
×ÖÄ» hopefully some of you in this room, discovered
×ÖÄ» 05: 00:06:01 that chemistry
×ÖÄ» was actually a lot of fun, and that the
×ÖÄ» 06: 00:06:05 chemistry I got
×ÖÄ» in college was pretty much nothing like the
×ÖÄ» 06: 00:06:07 chemistry I had seen in high school.
×ÖÄ» 06: 00:06:09 So, let me
×ÖÄ» introduce you to some of the topics we are
×ÖÄ» 06: 00:06:14 going to be covering in chemistry this semester.
×ÖÄ» 06: 00:06:18 So, there's
×ÖÄ» more detail on your syllabus -- a detail of what
×ÖÄ» 06: 00:06:21 we'll cover every day,
×ÖÄ» but these are the kind of basic
×ÖÄ» 06: 00:06:23 things that were covering,
×ÖÄ» and you don't need to write this
×ÖÄ» 06: 00:06:24 down, you'll become familiar with it as
×ÖÄ» 06: 00:06:27 the semester goes on.
×ÖÄ» 06: 00:06:29 We start out with some really basic principles.
×ÖÄ» 06: 00:06:34 So, up here, atomic theory, periodic table, bonding,
×ÖÄ» 06: 00:06:35 structures and molecules.
×ÖÄ» 06: 00:06:40 And there will
×ÖÄ» be a little bit of history in there, but this
×ÖÄ» 06: 00:06:45 is mostly modern
×ÖÄ» chemistry and represents the basic properties
×ÖÄ» 06: 00:06:49 of matter, and it's basic properties of all matter,
×ÖÄ» 06: 00:06:52 including living matter,
×ÖÄ» which was what really interested me,
×ÖÄ» 06: 00:06:55 that connection between chemistry and biology.
×ÖÄ» 06: 00:06:57 So, then we go to thermodynamics and chemical
×ÖÄ» 06: 00:07:01 equilibrium,
×ÖÄ» and this is really about chemical reactions --
×ÖÄ» 07: 00:07:04 weather a reaction will go,
×ÖÄ» will it be spontaneous, if
×ÖÄ» 07: 00:07:06 there an equilibrium, what direction will the
×ÖÄ» 07: 00:07:09 reaction be shifted in.
×ÖÄ» 07: 00:07:12 And then, of course,
×ÖÄ» not just whether the reaction will
×ÖÄ» 07: 00:07:15 occur but, how fast it occurs is really important.
×ÖÄ» 07: 00:07:19 So, that's
×ÖÄ» kinetics -- how fast a reaction will go, and from
×ÖÄ» 07: 00:07:22 the perspective of someone who's a biochemist, I'm
×ÖÄ» 07: 00:07:25 interested
×ÖÄ» in kinetics and enzyme kinetics, and thinking
×ÖÄ» 07: 00:07:29 about molecules that catalyze reactions in the body.
×ÖÄ» 07: 00:07:32 And then,
×ÖÄ» there's acid base equilibrium, and also oxidation
×ÖÄ» 07: 00:07:36 reduction reactions,
×ÖÄ» and what is true is that most reactions
×ÖÄ» 07: 00:07:38 that occur are
×ÖÄ» either catalyzed by either some kind of acid
×ÖÄ» 07: 00:07:42 base catalysis
×ÖÄ» or involve some kind of oxidation reduction
×ÖÄ» 07: 00:07:48 reaction, and so,
×ÖÄ» this sort of represents a lot of the basic
×ÖÄ» 07: 00:07:51 way reactions go -- now,
×ÖÄ» whether that's a reaction in
×ÖÄ» 07: 00:07:53 your body or a reaction in a test tube -- it doesn't
×ÖÄ» 07: 00:07:56 matter, a lot of the same principles are involved.
×ÖÄ» 07: 00:07:58 And then, we also cover transition metals, which is
×ÖÄ» 07: 00:08:01 something that you often don't see in high school.
×ÖÄ» 08: 00:08:04 And transition metals,
×ÖÄ» those all medals in the middle of
×ÖÄ» 08: 00:08:07 your periodic table,
×ÖÄ» have some really unique properties, which
×ÖÄ» 08: 00:08:09 are exploited again in reactions that occur in your
×ÖÄ» 08: 00:08:13 body, and also
×ÖÄ» are utilized in industry, for example, so we'll
×ÖÄ» 08: 00:08:15 talk about some of those unique properties.
×ÖÄ» 08: 00:08:20 And if we put all of that together, we get the real
×ÖÄ» 08: 00:08:22 fundamentals that you need to go on and study -- any
×ÖÄ» 08: 00:08:24 kind of curriculum that involves chemistry.
×ÖÄ» 08: 00:08:28 So, these are all the fundamentals that are involved
×ÖÄ» 08: 00:08:31 in chemistry
×ÖÄ» that relate to physical chemistry, organic
×ÖÄ» 08: 00:08:35 chemistry, inorganic chemistry,
×ÖÄ» biological chemistry, and are a
×ÖÄ» 08: 00:08:38 solid foundation
×ÖÄ» for studying any kind of life science.
×ÖÄ» 08: 00:08:42 So, I congratulate
×ÖÄ» you of being here in this class, this is
×ÖÄ» 08: 00:08:45 really good solid foundation for whatever you go on
×ÖÄ» 08: 00:08:47 to do, here at MIT.
×ÖÄ» 08: 00:08:50 So, normally at this point,
×ÖÄ» we do actually start class with a
×ÖÄ» 08: 00:08:54 little bit
×ÖÄ» of history from alchemy to modern chemistry,
×ÖÄ» 08: 00:08:58 but I decided to skip that this year.
×ÖÄ» 08: 00:09:00 If you are interested in that,
×ÖÄ» it's never required on any
×ÖÄ» 09: 00:09:04 test, it never has been,
×ÖÄ» but if you're interested in that there
×ÖÄ» 09: 00:09:08 is an OCW lecture, which you can listen to that's an
×ÖÄ» 09: 00:09:10 excellent lecture by Professor Sylvia Ceyer on that.
×ÖÄ» 09: 00:09:13 But today instead,
×ÖÄ» I thought I would give you some examples of
×ÖÄ» 09: 00:09:19 modern chemistry
×ÖÄ» -- why people now need to know chemistry,
×ÖÄ» 09: 00:09:21 what they're doing with chemistry, what is chemistry
×ÖÄ» 09: 00:09:26 research here at MIT,
×ÖÄ» and how does it utilize these basic
×ÖÄ» 09: 00:09:29 principles,
×ÖÄ» which we'll be talking about in the course.
×ÖÄ» 09: 00:09:32 So, I'll start with my colleague, Professor
×ÖÄ» 09: 00:09:33 Joanne Stubbe.
×ÖÄ» 09: 00:09:35 She studies molecules, in particular she studies
×ÖÄ» 09: 00:09:37 biological molecules.
×ÖÄ» 09: 00:09:41 And, so one of
×ÖÄ» the things she's very interested in is how this
×ÖÄ» 09: 00:09:45 anti-cancer drug, gemcitabine, works in the body.
×ÖÄ» 09: 00:09:48 So, it inhibits an enzyme,
×ÖÄ» and she's interested in knowing
×ÖÄ» 09: 00:09:49 how that really works.
×ÖÄ» 09: 00:09:52 So,
×ÖÄ» enzymes are made up of amino acids, you have long
×ÖÄ» 09: 00:09:55 chains of
×ÖÄ» amino acids that form together into a protein
×ÖÄ» 09: 00:09:59 molecules,
×ÖÄ» protein molecules in your body often act as enzymes,
×ÖÄ» 09: 00:10:00 catalyzing reactions.
×ÖÄ» 10: 00:10:03 So, she is
×ÖÄ» interested in how this molecule, gemcitabine,
×ÖÄ» 10: 00:10:06 inhibits an enzyme.
×ÖÄ» 10: 00:10:09 So, to do those studies, she needs to know a lot of
×ÖÄ» 10: 00:10:10 the stuff on this list.
×ÖÄ» 10: 00:10:13 Of course,
×ÖÄ» she needs to know the basic principles, but she's
×ÖÄ» 10: 00:10:15 also talking
×ÖÄ» about it an enzyme, so she needs to know
×ÖÄ» 10: 00:10:17 about enzyme catalysis.
×ÖÄ» 10: 00:10:20 She needs to know this enzyme works by both
×ÖÄ» 10: 00:10:23 acid base chemistry, and oxidation reduction.
×ÖÄ» 10: 00:10:26 It has two irons that are involved in doing the
×ÖÄ» 10: 00:10:29 chemistry, so it includes transition metals.
×ÖÄ» 10: 00:10:33 She thinks about how things bind,
×ÖÄ» how the natural reactants
×ÖÄ» 10: 00:10:35 binds, how the inhibitor binds,
×ÖÄ» and so she needs to know what
×ÖÄ» 10: 00:10:37 happens to
×ÖÄ» the chemical equilibrium, she needs to know
×ÖÄ» 10: 00:10:40 about the
×ÖÄ» thermodynamics of those binding events, and, of
×ÖÄ» 10: 00:10:43 course, everything, all the basic principles,
×ÖÄ» 10: 00:10:44 are required here.
×ÖÄ» 10: 00:10:48 So, to do this
×ÖÄ» biochemistry research, she needs to know all
×ÖÄ» 10: 00:10:52 of these things,
×ÖÄ» and she has really made tremendous progress
×ÖÄ» 10: 00:10:55 in understanding how gemcitabine works, and it is
×ÖÄ» 10: 00:10:59 not so toxic, so it's a really good thing to have
×ÖÄ» 10: 00:11:01 in chemotherapy.
×ÖÄ» 11: 00:11:04 So, in addition
×ÖÄ» to studying molecules, chemists often want
×ÖÄ» 11: 00:11:08 to make molecules, such as Tim Jamison, who's an
×ÖÄ» 11: 00:11:09 organic chemist.
×ÖÄ» 11: 00:11:14 So, you will hear,
×ÖÄ» probably, hopefully, in this presidential
×ÖÄ» 11: 00:11:17 debate about
×ÖÄ» the environment and about why saving the
×ÖÄ» 11: 00:11:19 environment is important.
×ÖÄ» 11: 00:11:22 And one of the
×ÖÄ» things you often hear about in this discussion
×ÖÄ» 11: 00:11:25 is about our
×ÖÄ» oceans and about rainforests, and part of the
×ÖÄ» 11: 00:11:29 reason why
×ÖÄ» people want to protect those areas is because
×ÖÄ» 11: 00:11:32 you find a lot of natural products in those regions.
×ÖÄ» 11: 00:11:34 So, a natural product is something that is made by
×ÖÄ» 11: 00:11:37 nature, and
×ÖÄ» often natural products, whether it comes from
×ÖÄ» 11: 00:11:40 a plant or a marine organism have some really good,
×ÖÄ» 11: 00:11:41 useful properties.
×ÖÄ» 11: 00:11:45 And so, one
×ÖÄ» particular compound has anti-tumor properties.
×ÖÄ» 11: 00:11:48 So, again, along this line of cancer research.
×ÖÄ» 11: 00:11:51 So, Tim Jamison's
×ÖÄ» lab figured out how to make this thing.
×ÖÄ» 11: 00:11:55 And often that's really important, because you can't
×ÖÄ» 11: 00:11:59 get enough of
×ÖÄ» the organism that naturally makes it, to be able
×ÖÄ» 11: 00:12:01 to grind
×ÖÄ» that organism up and have enough that you can
×ÖÄ» 12: 00:12:03 actually use as a medicine.
×ÖÄ» 12: 00:12:05 So, you have to make more of it, because nature
×ÖÄ» 12: 00:12:06 doesn't make enough.
×ÖÄ» 12: 00:12:10 So, it's
×ÖÄ» very important to figure out how to do that.
×ÖÄ» 12: 00:12:13 So, in doing that, Tim Jamison's lab needs a
×ÖÄ» 12: 00:12:15 lot of these things.
×ÖÄ» 12: 00:12:18 So, he needs
×ÖÄ» a lot of knowledge of bonding, he wants to
×ÖÄ» 12: 00:12:20 form bonds in making this.
×ÖÄ» 12: 00:12:22 He needs to
×ÖÄ» know about the structures of the molecules,
×ÖÄ» 12: 00:12:25 because if the
×ÖÄ» structure is wrong it's not going to work.
×ÖÄ» 12: 00:12:28 And often, if
×ÖÄ» you want to make a lot of it, you have to think
×ÖÄ» 12: 00:12:29 about the
×ÖÄ» thermodynamics of the system, how fast the reactions
×ÖÄ» 12: 00:12:32 will go and kinetics,
×ÖÄ» and then whether they'll go, the
×ÖÄ» 12: 00:12:38 thermodynamics,
×ÖÄ» and sometimes then you need to adjust the
×ÖÄ» 12: 00:12:41 reactions, maybe use a transition metal to
×ÖÄ» 12: 00:12:42 make it go better.
×ÖÄ» 12: 00:12:45 So, these are
×ÖÄ» all the things that Tim Jamison needs to know
×ÖÄ» 12: 00:12:47 to do organic chemistry.
×ÖÄ» 12: 00:12:49 So, you'll
×ÖÄ» be learning in this class a great preparation
×ÖÄ» 12: 00:12:53 for 512, which is organic chemistry.
×ÖÄ» 12: 00:12:57 In addition
×ÖÄ» to studying molecules and making molecules,
×ÖÄ» 12: 00:13:01 some chemists
×ÖÄ» want to detect molecules, and a chemist who
×ÖÄ» 13: 00:13:04 likes to detect molecules is Tim Swager.
×ÖÄ» 13: 00:13:07 So, Tim
×ÖÄ» Swager's lab has designed sensors that detect
×ÖÄ» 13: 00:13:11 vapors, and so they will detect TNT, for example.
×ÖÄ» 13: 00:13:14 And so, he has put this chemistry to use in this
×ÖÄ» 13: 00:13:19 robotic arm
×ÖÄ» and they call it Fido, because often dogs are
×ÖÄ» 13: 00:13:22 the creatures
×ÖÄ» that have to go out and detect these things,
×ÖÄ» 13: 00:13:26 and it's not
×ÖÄ» a great job if you're a dog to be sent out to
×ÖÄ» 13: 00:13:28 see whether there was an explosive and discover yes,
×ÖÄ» 13: 00:13:30 there was, a little bit too late.
×ÖÄ» 13: 00:13:35 So, this is a
×ÖÄ» much nicer way to detect chemicals with this
×ÖÄ» 13: 00:13:39 robotic arm,
×ÖÄ» and here's a picture of it in use in Iraq.
×ÖÄ» 13: 00:13:43 So, in doing this, if you go down to kind of a basic
×ÖÄ» 13: 00:13:47 principles that
×ÖÄ» Tim needed to know about, oxidation reduction
×ÖÄ» 13: 00:13:50 was really key in developing this technology, so
×ÖÄ» 13: 00:13:53 we'll talk about that.
×ÖÄ» 13: 00:13:57 So, my final
×ÖÄ» example is from Alan Davidson's lab, and Alan
×ÖÄ» 13: 00:14:01 is an inorganic
×ÖÄ» chemist -- he loved those transition metals
×ÖÄ» 14: 00:14:04 and they're unique properties,
×ÖÄ» and he designed this compound,
×ÖÄ» 14: 00:14:08 it's called Cardiolite,
×ÖÄ» and it's used in heart imaging.
×ÖÄ» 14: 00:14:12 So, many people
×ÖÄ» have relatives they know of that have had to
×ÖÄ» 14: 00:14:16 have their heart imaged -- heart disease is a major
×ÖÄ» 14: 00:14:18 problem in the United States,
×ÖÄ» and there's a good chance that
×ÖÄ» 14: 00:14:21 they had Cardiolite given to them to help in that
×ÖÄ» 14: 00:14:22 imaging process.
×ÖÄ» 14: 00:14:27 So, this again,
×ÖÄ» takes advantage of those great unique
×ÖÄ» 14: 00:14:30 properties of transition metals, which we'll talk
×ÖÄ» 14: 00:14:32 about in this course.
×ÖÄ» 14: 00:14:36 So, again, all together,
×ÖÄ» this is the basis for modern
×ÖÄ» 14: 00:14:39 chemistry,
×ÖÄ» and examples I just gave you, are some of the
×ÖÄ» 14: 00:14:42 things that
×ÖÄ» modern chemists are working on -- some of the
×ÖÄ» 14: 00:14:45 issues that
×ÖÄ» our country faces and our world faces, and how
×ÖÄ» 14: 00:14:48 chemistry is involved in that.
×ÖÄ» 14: 00:14:52 So, not only
×ÖÄ» will you have the fundamental knowledge to go on
×ÖÄ» 14: 00:14:56 and take
×ÖÄ» more courses in chemistry, you will also have
×ÖÄ» 14: 00:14:59 the fundamental
×ÖÄ» knowledge to go on and do undergraduate
×ÖÄ» 14: 00:15:04 research here,
×ÖÄ» and here are some of the 5.111 undergraduate
×ÖÄ» 15: 00:15:07 researchers that have come through my lab, in
×ÖÄ» 15: 00:15:10 particular, from this class.
×ÖÄ» 15: 00:15:14 So, it's a really nice solid foundation.
×ÖÄ» 15: 00:15:17 So, I want to
×ÖÄ» encourage you to set some of your likes and
×ÖÄ» 15: 00:15:22 dislikes from
×ÖÄ» high school aside when you come to MIT, because
×ÖÄ» 15: 00:15:25 at MIT you often see disciplines taught and
×ÖÄ» 15: 00:15:28 emphasize a very different fashion than what
×ÖÄ» 15: 00:15:29 you've seen before.
×ÖÄ» 15: 00:15:31 And you may
×ÖÄ» discover that the thing you came here to study is
×ÖÄ» 15: 00:15:34 not the thing
×ÖÄ» that you really want to study after all.
×ÖÄ» 15: 00:15:38 One other thing
×ÖÄ» that I'll say to you is that I said these
×ÖÄ» 15: 00:15:41 words at one point,
×ÖÄ» it's true, I said, when I was in high
×ÖÄ» 15: 00:15:49 school, I said, "I hate chemistry." And now, I do
×ÖÄ» 15: 00:15:56 chemistry every day and will for the rest my life.
×ÖÄ» 15: 00:15:57 I love chemistry now.
×ÖÄ» 15: 00:15:59 Be very careful what you say.
×ÖÄ» 15: 00:16:01 Have any of you made that statement about
×ÖÄ» 16: 00:16:04 hating a subject?
×ÖÄ» 16: 00:16:06 Tell me later what it is you're going to be doing
×ÖÄ» 16: 00:16:09 for the rest of your life.
×ÖÄ» 16: 00:16:13 So, at MIT
×ÖÄ» things are very different, and keep an open
×ÖÄ» 16: 00:16:16 mind,
×ÖÄ» explore new areas -- take advantage of being at this
×ÖÄ» 16: 00:16:19 amazing place
×ÖÄ» for science and technology and you may surprise
×ÖÄ» 16: 00:16:25 yourself in what you really enjoy learning about.
×ÖÄ» 16: 00:16:28 So, that's a
×ÖÄ» little bit about the chemistry that we're going
×ÖÄ» 16: 00:16:32 to cover in this class,
×ÖÄ» and now I'm going to talk a little
×ÖÄ» 16: 00:16:35 bit about some of the policies and procedures.
×ÖÄ» 16: 00:16:39 But first I
×ÖÄ» need to introduce my co-instructor for this
×ÖÄ» 16: 00:16:43 class, and let me just put up her picture, you'll
×ÖÄ» 16: 00:16:44 see her in a minute.
×ÖÄ» 16: 00:16:47 So, Dr. Beth Vogel Taylor.
×ÖÄ» 16: 00:16:50 So, all
×ÖÄ» chemistry courses are team taught, so you have a
×ÖÄ» 16: 00:16:53 different
×ÖÄ» lecturer for the first half than the second
×ÖÄ» 16: 00:16:56 half, and Dr.
×ÖÄ» Taylor will be doing most of the first half
×ÖÄ» 16: 00:16:58 lectures, and I'll be doing most of the second
×ÖÄ» 16: 00:16:59 half lectures.
×ÖÄ» 16: 00:17:02 So, Dr.
×ÖÄ» Taylor will take you from atomic theory through
×ÖÄ» 17: 00:17:05 thermodynamics,
×ÖÄ» and I'll start up with chemical equilibrium,
×ÖÄ» 17: 00:17:09 talk to about kinetics,
×ÖÄ» acid base, oxidation reduction
×ÖÄ» 17: 00:17:10 and transition metals.
×ÖÄ» 17: 00:17:14 So, you will
×ÖÄ» have both of us as lecturers in this class.
×ÖÄ» 17: 00:17:18 Now, in the past,
×ÖÄ» sometimes students have found this whole
×ÖÄ» 17: 00:17:20 thing a little frustrating,
×ÖÄ» that they just get used to one
×ÖÄ» 17: 00:17:23 lecture style,
×ÖÄ» and then all of a sudden there's another
×ÖÄ» 17: 00:17:26 lecture style, and that can be true.
×ÖÄ» 17: 00:17:30 I mean sometimes
×ÖÄ» the styles of the two professors couldn't
×ÖÄ» 17: 00:17:32 be more
×ÖÄ» different -- think McCain/Palin, odd couples.
×ÖÄ» 17: 00:17:39 Sometimes they're more similar,
×ÖÄ» and when I first, about a year
×ÖÄ» 17: 00:17:43 and a half ago,
×ÖÄ» got to know Dr. Taylor, we sort of realized
×ÖÄ» 17: 00:17:46 that we had
×ÖÄ» very similar styles, and we got very excited
×ÖÄ» 17: 00:17:49 about the idea
×ÖÄ» that we could teach together, so that there
×ÖÄ» 17: 00:17:51 would be
×ÖÄ» much more continuity throughout the semester.
×ÖÄ» 17: 00:17:54 And so, Dr.
×ÖÄ» Taylor had been teaching the first half of the
×ÖÄ» 17: 00:17:58 material in the Spring,
×ÖÄ» and I had been teaching the second
×ÖÄ» 17: 00:18:00 half of the
×ÖÄ» material in the Fall, and we thought wouldn't
×ÖÄ» 18: 00:18:04 it be great
×ÖÄ» if we got together and taught in the Fall.
×ÖÄ» 18: 00:18:06 So, this was actually,
×ÖÄ» for a variety of reasons, a very
×ÖÄ» 18: 00:18:10 complicated
×ÖÄ» thing to request and do, and so we started a
×ÖÄ» 18: 00:18:13 campaign and
×ÖÄ» campaigned for a year and a half that we should
×ÖÄ» 18: 00:18:17 be allowed to
×ÖÄ» do this course together, and finally just a
×ÖÄ» 18: 00:18:20 few weeks ago
×ÖÄ» in August -- we really didn't know up until
×ÖÄ» 18: 00:18:24 almost when this
×ÖÄ» course started -- that permission was granted.
×ÖÄ» 18: 00:18:29 So, I have to say,
×ÖÄ» I am very excited now to introduce you to
×ÖÄ» 18: 00:18:33 Dr. Taylor,
×ÖÄ» who I would be teaching with this semester --
×ÖÄ» 18: 00:18:36 limited
×ÖÄ» engagement -- who will tell you about some of
×ÖÄ» 18: 00:18:37 the course policies.
×ÖÄ» 18: 00:18:47 PROFESSOR: Okay,
×ÖÄ» so before we get to some of these course
×ÖÄ» 18: 00:18:51 policies, I
×ÖÄ» think I'll tell you a little bit about my path
×ÖÄ» 18: 00:18:52 to chemistry as well.
×ÖÄ» 18: 00:18:56 Professor
×ÖÄ» Drennan explained that not everyone that ends up
×ÖÄ» 18: 00:19:00 as a chemist
×ÖÄ» started off that way on their first class
×ÖÄ» 19: 00:19:03 freshman year, for example, in chemistry.
×ÖÄ» 19: 00:19:06 And in fact,
×ÖÄ» if you talk to a lot of chemists, if you talk to
×ÖÄ» 19: 00:19:09 some of the graduate students,
×ÖÄ» maybe your TA, you'll find that
×ÖÄ» 19: 00:19:12 that phrase, "I hate chemistry," Has maybe been
×ÖÄ» 19: 00:19:16 uttered by more
×ÖÄ» than one us at some point in our lives before
×ÖÄ» 19: 00:19:19 we realized,
×ÖÄ» and once it happens you don't go back, that
×ÖÄ» 19: 00:19:22 actually you
×ÖÄ» love chemistry and it's hard to even remember a
×ÖÄ» 19: 00:19:24 point where
×ÖÄ» you didn't see all of these connections that
×ÖÄ» 19: 00:19:26 it provided for you.
×ÖÄ» 19: 00:19:29 To give a
×ÖÄ» little background of where I was, sitting where
×ÖÄ» 19: 00:19:32 maybe you are
×ÖÄ» today on the first day of chemistry, when I
×ÖÄ» 19: 00:19:35 left high school, I had no interest in chemistry
×ÖÄ» 19: 00:19:36 whatsoever.
×ÖÄ» 19: 00:19:39 And I have only one strong memory from high school
×ÖÄ» 19: 00:19:43 chemistry, and that memory is shown right here, and
×ÖÄ» 19: 00:19:45 that is the common ions.
×ÖÄ» 19: 00:19:47 Did you guys have to learn the common ions?
×ÖÄ» 19: 00:19:51 Does anyone have
×ÖÄ» that in their brain somewhere for ready use?
×ÖÄ» 19: 00:19:54 I don't, in fact, so it's actually okay if you don't
×ÖÄ» 19: 00:19:57 know all your common ions, if you missed that part.
×ÖÄ» 19: 00:20: that
×ÖÄ» 20: 00:20:02 I didn't learn them,
×ÖÄ» and that was really bad because it kept
×ÖÄ» 20: 00:20:06 coming up,
×ÖÄ» but the other thing I remember is that I had no
×ÖÄ» 20: 00:20:07 idea why they were important.
×ÖÄ» 20: 00:20:11 I didn't really
×ÖÄ» understand what any of these molecules were.
×ÖÄ» 20: 00:20:14 I certainly
×ÖÄ» didn't understand how they even connected really
×ÖÄ» 20: 00:20:17 to chemical reactions, much less other disciplines
×ÖÄ» 20: 00:20:18 that I was interested in.
×ÖÄ» 20: 00:20:20 I couldn't have told you,
×ÖÄ» for example, if we look at a
×ÖÄ» 20: 00:20:22 phosphate group, that that's going to be incredibly
×ÖÄ» 20: 00:20:26 important in DNA,
×ÖÄ» that it's also an incredibly important
×ÖÄ» 20: 00:20:28 group when
×ÖÄ» you're dealing with proteins and whether you're
×ÖÄ» 20: 00:20:31 turning the function of a protein on or off.
×ÖÄ» 20: 00:20:33 So really, I just had no context for the chemistry.
×ÖÄ» 20: 00:20:37 So, when I started in college,
×ÖÄ» that wasn't even an option for
×ÖÄ» 20: 00:20:39 me and I was
×ÖÄ» interested in a lot of things, chemistry
×ÖÄ» 20: 00:20:40 not being one.
×ÖÄ» 20: 00:20:45 But one that
×ÖÄ» I was very interested in was biology, and
×ÖÄ» 20: 00:20:48 the reason was
×ÖÄ» we did a lot of cool labs in high school, I
×ÖÄ» 20: 00:20:51 loved doing the
×ÖÄ» dissections -- it was very interesting to me
×ÖÄ» 20: 00:20:54 to think about
×ÖÄ» how different organs worked, how the heart
×ÖÄ» 20: 00:20:56 could be a pump, how the lungs worked.
×ÖÄ» 20: 00:20:59 And then when
×ÖÄ» we got to more of a cellular level, it was even
×ÖÄ» 20: 00:21:02 more interesting
×ÖÄ» to see that we could actually understand how
×ÖÄ» 21: 00:21:07 our body worked
×ÖÄ» as low of a level as thinking about cells.
×ÖÄ» 21: 00:21:10 And so, that
×ÖÄ» was a clear major for me to pick -- I actually
×ÖÄ» 21: 00:21:12 also was considering English and ended up being a
×ÖÄ» 21: 00:21:12 minor in English.
×ÖÄ» 21: 00:21:15 But, I think what most of you,
×ÖÄ» actually having come to MIT,
×ÖÄ» 21: 00:21:18 have probably
×ÖÄ» realized is sometimes it's nice to major in
×ÖÄ» 21: 00:21:21 a science,
×ÖÄ» because you can't just pick up a reaction and do
×ÖÄ» 21: 00:21:23 it in your kitchen on the weekend, where as you can
×ÖÄ» 21: 00:21:25 sometimes join a book group and do that.
×ÖÄ» 21: 00:21:28 So, it's kind
×ÖÄ» of nice to major in the thing that you're going
×ÖÄ» 21: 00:21:31 to get to have the opportunity to do for the rest
×ÖÄ» 21: 00:21:32 of your life.
×ÖÄ» 21: 00:21:34 So, I actually also started pre-med.
×ÖÄ» 21: 00:21:37 Is anyone else pre-med here?
×ÖÄ» 21: 00:21:38 Okay, so a pretty good showing.
×ÖÄ» 21: 00:21:41 So maybe you can
×ÖÄ» relate to some of the reasons I wanted to be
×ÖÄ» 21: 00:21:43 pretty pre-med -- part of it was the interest in the
×ÖÄ» 21: 00:21:44 science and the biology.
×ÖÄ» 21: 00:21:47 Also, I wanted
×ÖÄ» to help people -- it seemed like a really
×ÖÄ» 21: 00:21:50 clear way that
×ÖÄ» I could have a career that was challenging
×ÖÄ» 21: 00:21:53 and involved in science, but also helping others.
×ÖÄ» 21: 00:21:56 So, it seemed
×ÖÄ» like a good start for me, pre-med/bio, and I
×ÖÄ» 21: 00:22:00 signed up for my
×ÖÄ» bio class -- I found out, as Professor Drennan
×ÖÄ» 22: 00:22:03 did, that I had to take chemistry as well.
×ÖÄ» 22: 00:22:06 I wasn't as upset,
×ÖÄ» I was sort of a neutral chemistry person
×ÖÄ» 22: 00:22:08 at this point,
×ÖÄ» but I thought it was pretty smart to get it over
×ÖÄ» 22: 00:22:11 with on the first semester, so that's what I did.
×ÖÄ» 22: 00:22:16 And my plan
×ÖÄ» was going along fine until something happened,
×ÖÄ» 22: 00:22:19 and what
×ÖÄ» happened was that chemistry was just way more
×ÖÄ» 22: 00:22:21 interesting than I anticipated.
×ÖÄ» 22: 00:22:25 So, my perfect
×ÖÄ» pre-med/bio plan was getting a little shaken
×ÖÄ» 22: 00:22:27 right from the start,
×ÖÄ» and the reason that it was getting
×ÖÄ» 22: 00:22:30 taken was because
×ÖÄ» I would learn this new principal in chemistry
×ÖÄ» 22: 00:22:33 and because
×ÖÄ» I was taking bio with the same time, I could
×ÖÄ» 22: 00:22:34 see the connections.
×ÖÄ» 22: 00:22:38 And at one point I realized,
×ÖÄ» "Oh, my gosh, chemistry is just
×ÖÄ» 22: 00:22:41 biology, it's
×ÖÄ» just looking at one level deeper." So actually,
×ÖÄ» 22: 00:22:45 all of my
×ÖÄ» interest in biology was quickly transferred to
×ÖÄ» 22: 00:22:47 saying, "Wow,
×ÖÄ» now I can think about things on the molecular
×ÖÄ» 22: 00:22:50 level." And one of the molecules that caught my
×ÖÄ» 22: 00:22:53 attention first,
×ÖÄ» and I can't remember if this was freshman
×ÖÄ» 22: 00:22:56 or sophomore
×ÖÄ» year in high school, was the first time I
×ÖÄ» 22: 00:22:58 actually took meaning in looking at a chemical
×ÖÄ» 22: 00:23:01 structure,
×ÖÄ» and that was with the structure of penicillin
×ÖÄ» 23: 00:23:03 here, and I know that all of you are familiar with
×ÖÄ» 23: 00:23:06 penicillin,
×ÖÄ» whether or not you know the structure or not, but
×ÖÄ» 23: 00:23:09 the most important
×ÖÄ» part of this structure is the four-membered
×ÖÄ» 23: 00:23:13 ring here, the beta-lactam,
×ÖÄ» and this was the first time I
×ÖÄ» 23: 00:23:16 thought I could actually understand how a molecule
×ÖÄ» 23: 00:23:19 worked because I knew something about chemistry.
×ÖÄ» 23: 00:23:23 So, for example
×ÖÄ» with penicillin what it does is it inhibits an
×ÖÄ» 23: 00:23:27 enzyme that
×ÖÄ» builds the cell wall in bacteria, the bacterial
×ÖÄ» 23: 00:23:30 cell wall,
×ÖÄ» and if I thought about what I'd learned in
×ÖÄ» 23: 00:23:32 chemistry --
×ÖÄ» some of you know this from high school, some of
×ÖÄ» 23: 00:23:35 you will be
×ÖÄ» very familiar with this soon, is that this
×ÖÄ» 23: 00:23:38 carbon here, for example, is bonded to three things.
×ÖÄ» 23: 00:23:43 Does anyone
×ÖÄ» know what angle those would like to be at?
×ÖÄ» 23: 00:23:44 120.
×ÖÄ» 23: 00:23:46 They want
×ÖÄ» to get as far away from each other possible,
×ÖÄ» 23: 00:23:48 the ideal angle is 120.
×ÖÄ» 23: 00:23:51 But what we
×ÖÄ» have here is a four-membered ring, so what
×ÖÄ» 23: 00:23:54 angle does that have to be, that bond?
×ÖÄ» 23: 00:23:56 90 degrees.
×ÖÄ» 23: 00:23:58 So, we have a
×ÖÄ» problem here if we're thinking about keeping
×ÖÄ» 23: 00:24:01 things at the lowest energy,
×ÖÄ» so there's a lot of ring
×ÖÄ» 24: 00:24:02 strain in the system.
×ÖÄ» 24: 00:24:05 And I was
×ÖÄ» incredibly excited that I could look at that and
×ÖÄ» 24: 00:24:07 realize it and say "Wow,
×ÖÄ» that's why it's so reactive, that's
×ÖÄ» 24: 00:24:10 why it's such a good medication," Because when it
×ÖÄ» 24: 00:24:13 comes into
×ÖÄ» contact with these bacterial cell wall building
×ÖÄ» 24: 00:24:17 enzyme, the
×ÖÄ» enzyme can actually react with this four-membered
×ÖÄ» 24: 00:24:21 ring and open
×ÖÄ» up the ring and relieve that ring strain.
×ÖÄ» 24: 00:24:24 So, now the
×ÖÄ» angles can open up all the way to 120 if it wants
×ÖÄ» 24: 00:24:26 to, and there's
×ÖÄ» no way it's going to form that ring again,
×ÖÄ» 24: 00:24:29 right,
×ÖÄ» because it's not going to back to those 90 degree
×ÖÄ» 24: 00:24:30 angles, if it can help it.
×ÖÄ» 24: 00:24:34 So now, the
×ÖÄ» enzyme is locked up with the penicillin molecule,
×ÖÄ» 24: 00:24:37 no more bacterial cell wall being built, and the
×ÖÄ» 24: 00:24:40 penicillin has effectively killed the bacteria.
×ÖÄ» 24: 00:24:42 So, that, for me,
×ÖÄ» was kind of the first connection that what
×ÖÄ» 24: 00:24:44 went, "Woah, wait a second,
×ÖÄ» I want to be thinking about these
×ÖÄ» 24: 00:24:49 molecules all
×ÖÄ» the way down to the level of individual atoms."
×ÖÄ» 24: 00:24:52 So, at this point, kept the pre-med, just switched
×ÖÄ» 24: 00:24:54 the major to chemistry.
×ÖÄ» 24: 00:24:56 The next problem came up when I went and took
×ÖÄ» 24: 00:24:58 organic chemistry.
×ÖÄ» 24: 00:25:01 So, if you're dead set on staying with bio, maybe, I
×ÖÄ» 25: 00:25:04 guess you have to take organic,
×ÖÄ» so this might happen to
×ÖÄ» 25: 00:25:06 you, just to warn you.
×ÖÄ» 25: 00:25:08 We started looking at all sorts of other kinds of
×ÖÄ» 25: 00:25:11 molecules that became very interesting to me.
×ÖÄ» 25: 00:25:14 I especially love thinking about vitamins and drugs,
×ÖÄ» 25: 00:25:17 because I do
×ÖÄ» have that interest in medicine and human health.
×ÖÄ» 25: 00:25:20 These are
×ÖÄ» actually all examples that we'll talk about in
×ÖÄ» 25: 00:25:23 freshman chemistry at some point, as an example of a
×ÖÄ» 25: 00:25:25 connection between
×ÖÄ» a chemical principle we learn, and what we
×ÖÄ» 25: 00:25:28 can know about how it functions.
×ÖÄ» 25: 00:25:31 But what
×ÖÄ» happened here was I thought "Oh, my gosh, now I
×ÖÄ» 25: 00:25:34 could actually,
×ÖÄ» using my chemical knowledge, think about
×ÖÄ» 25: 00:25:38 synthesizing these molecules,
×ÖÄ» or maybe coming up with new
×ÖÄ» 25: 00:25:41 ways to synthesize them better or synthesize
×ÖÄ» 25: 00:25:42 different molecules.
×ÖÄ» 25: 00:25:46 And the real clincher was when I started doing some
×ÖÄ» 25: 00:25:47 undergraduate research.
×ÖÄ» 25: 00:25:51 Any potential
×ÖÄ» UROPs out there -- anyone planning to do
×ÖÄ» 25: 00:25:53 a research at some point?
×ÖÄ» 25: 00:25:54 Excellent.
×ÖÄ» 25: 00:25:55 Okay.
×ÖÄ» 25: 00:25:58 So, just to be warned,
×ÖÄ» you might fall in love with the
×ÖÄ» 25: 00:26:00 subject you do your UROP in.
×ÖÄ» 26: 00:26:02 This is one of our summer students from this past
×ÖÄ» 26: 00:26:04 summer, who is also premed.
×ÖÄ» 26: 00:26:07 She's continuing to be pre-med, which is fantastic.
×ÖÄ» 26: 00:26:09 That didn't happen to me -- once I got into the lab,
×ÖÄ» 26: 00:26:10 I didn't want to leave.
×ÖÄ» 26: 00:26:13 So, I thought, "You know what,
×ÖÄ» I think I'll change the medical
×ÖÄ» 26: 00:26:15 school plans and
×ÖÄ» now I'm going to go all the way -- chemistry
×ÖÄ» 26: 00:26:18 major, chemistry grad school."
×ÖÄ» And the reason I was able to do
×ÖÄ» 26: 00:26:22 that and keep
×ÖÄ» with what my original intentions were was to
×ÖÄ» 26: 00:26:24 have a career
×ÖÄ» that was the fulfilling, in terms of helping
×ÖÄ» 26: 00:26:27 people and
×ÖÄ» being engaged in science, is all of a sudden I
×ÖÄ» 26: 00:26:31 realized, as chemists,
×ÖÄ» we can think about better ways to
×ÖÄ» 26: 00:26:34 build molecules that are important for making
×ÖÄ» 26: 00:26:35 medications.
×ÖÄ» 26: 00:26:38 Another thing
×ÖÄ» we can do is we can use our chemistry to
×ÖÄ» 26: 00:26:41 understand biological systems,
×ÖÄ» so we can help illucinate
×ÖÄ» 26: 00:26:44 pathways, maybe, that are implicated in disease.
×ÖÄ» 26: 00:26:47 So, the combination
×ÖÄ» of these two things had made my decision
×ÖÄ» 26: 00:26:50 and I ended up
×ÖÄ» coming here for graduate school, actually, and
×ÖÄ» 26: 00:26:53 working in Professor Imperiali's lab doing
×ÖÄ» 26: 00:26:56 bio-organic chemistry, which means that I synthesize
×ÖÄ» 26: 00:27:00 molecules, which I loved, and used them to study
×ÖÄ» 27: 00:27:01 biological systems.
×ÖÄ» 27: 00:27:05 So, really
×ÖÄ» I'm pretty happy with what I've gotten to do,
×ÖÄ» 27: 00:27:07 and I just want to say we're not trying to convert
×ÖÄ» 27: 00:27:11 all of them you pre-med people, by any means.
×ÖÄ» 27: 00:27:14 My roommate for
×ÖÄ» many years was going to medical school as I
×ÖÄ» 27: 00:27:17 was going to graduate school,
×ÖÄ» and we found we had so many
×ÖÄ» 27: 00:27:20 interesting
×ÖÄ» conversations about chemistry -- her from the
×ÖÄ» 27: 00:27:24 context of
×ÖÄ» practicing and using medications and talking about
×ÖÄ» 27: 00:27:26 how they worked on a molecular level, and me talking
×ÖÄ» 27: 00:27:28 about my research.
×ÖÄ» 27: 00:27:29