Chem 125 Lecture 19/3/08

Projected material

This material is for the exclusive use of Chem 125 students at Yale and may not

be copied or distributed further.

It is not readily understood without reference to notes from the lecture.

Enter on the white card in this order (no need to write the words “Name”, etc.)

Name (pronunciation hints if it’s not obvious)

Prefer to be Called (e.g. Jay, not Jethro)

Phone Number (and E-mail if you haven't heard from me yet)

Hometown with zip code

Previous school & its location

Name of best science teacher you’ve had (with subject)

Prospective major(s)

Put any comments / questions on back.

Hewlett Foundation Supports Online Debut of Free Courses

With generous support from the William and Flora Hewlett Foundation, Yale University recently launched Open Yale Courses, an innovative project offering some of Yale’s most popular courses online and free of charge. The initiative gives learners from around the world access to the full content of selected college-level courses in various formats, including downloadable and streaming video, audio, and searchable transcripts of each lecture. Syllabi, reading assignments, problem sets, and other materials accompany the courses…

The Open Yale Courses project is produced and supported by the Yale Center for Media and Instructional Innovation (CMI2)

http://yaletomorrow.yale.edu/news/openyale.htmlMeet: Jeff, Maria, Jude, Neil

This includes in-class discussion and the class Wiki(for which we need your permission)

For over 150 years organic courses have

tended to acquire daunting reputations

HELP !

PowerPoints / Lecture NotesDesigned for Mac - Compatible with PC & viewer

(please help identify problems)

Course Website: https://webspace.yale.edu/chem125/

assigned problems or questionsprevious exams and answer keys

Course Wiki at ClassesV2initial updates due within 36 hours of presentation

in-class discussion / e-mail questions

(There will probably be a Text Book for the Spring semester)

HELP ! Instructor : Prof. J. M. McBride (Thurs 1-2:30 or by appt)

Grad Student TAs: Filip Kolundzic (Thurs 7-9 pm) Nathan Schley (Mon 7-9 pm)

Other Chem 125 students!

Tina HoJustin Kim (Sunday 8-10 pm) Drew Klein

Alumni Peer Tutors:

Course Alumni (web advice)

Sign up on-line (pro-forma)

Exam Dates

10 lectures

Fri. Sept 269 lect

Mon. Oct 209 lect

Fri. Nov. 149 lect

Wed. Dec 17

100 pts

100 pts

100 pts

300 pts

Semester grade biased by faithfulness in timely problem set submission

Wiki Participation 50 pts

Total 650 pts

The characteristic comment on making a discovery is not “Eureka!” but rather

“Huh, that’s funny.”

• Learn enough about how chemistry works so that you know when to be astonished

Goals of Freshman Organic Chemistry:• Learn the crucial facts and vocabulary of Organic Chemistry

• Develop theoretical intuition about how Bonding works

• Learn from this model science how to be a creative scientist

• Develop good scientific taste (sense vs. nonsense)

Knowing to be astonished by something is the mind’s first step

toward discovery.

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Louis Pasteur

Savoir s'étonner à propos est le premier mouvement de l'esprit vers la découverte.

• Make the scientific transition from school to university

(molecular structure) (reactivity), and changes

• Have fun

Theory & Experiment Why do we require

Chem 126L?

Because Lab answers the

BigQuestionBig

How do you know?

John McBride(age 3)

How do you know?How do you know?

John McBride(age 38)

FourWays

of Knowing

Carolingian Bookpainter ~840 A.D.

(British Museum)

Moses Receivesthe Law Tablets

But Science is NOT Faith-Based!

Authority1) Divine

Authority2) Human

Science Ignores:1) Divine Authority

&

2) Human Authority

SCL Honor Roll

Do not suppose that I was a very deep thinker, or was marked as a precocious person. I was a very lively imaginative person, and could believe in the Arabian Nights as easily as in the Encyclopaedia. But facts were important to me, and saved me. I could trust a fact, and always cross-examined an assertion. So when I questioned Mrs. Marcet's book by such little experiments as I could find means to perform, and found it true to the facts as I could understand them, I felt that I had got hold of an anchor in chemical knowledge, and clung fast to it.

Michael Faraday, 1858

3) Experimental….Observation

When someone says science teaches such and such, he is using the word incorrectly. Science doesn't teach it; experience teaches it.

If they say to you science has shown such and such, you might ask, "How does science show it - how did the scientists find out - how, what, where?" Not science has shown, but this experiment, this effect has shown.

Learn from science that you must doubt the experts… Science is the belief inthe ignorance of experts.

(to Nat’l Science Teachers Assn. 1966)

Why quote Feynman?Because he is an expert?

Though literally “expert” means someone who has

done experiments.

Because what he says makes sense.

4) Logic

Modern Science got underway in the 17th

Century

1800

LavoisierOxidation

1900

PlanckQuantization

NewtonGravitation

LutherReformation

ColumbusNavigation

2000

Us

170016001500

CopernicusRevolution

Robert Hooke (Micrographia, 1665)

BaconInstauration

Shakespeare(1564-1616)

Galileo(1564-1642)

On his scholasticCambridge tutors:

"Men of sharp wits, shut up in their cells of a few authors, chiefly

Aristotle, their Dictator."

All the philosophy of nature which is now received, is either the philosophy of the Grecians, or that other of the alchemists…

The one is gathered out of a few vulgar observations, and the other out of a few experiments of a furnace.

The one never faileth to multiply words, and the other ever faileth to multiply gold.

Francis Bacon (1561-1626)

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Francis Bacon (1561-1626)

Instauratio MagnaThe Great Restoration

Novum OrganumInductive Scientific Method toreplace Aristotelian deduction

?

NASA/JPL/NIMA

JebelMusa

(Morocco)

Jebelal Tarik(Gibraltar)

PLUS ULTRA

Pillars of Hercules

Mediterranean - Classical World - Aristotle

"Many will pass through and knowledge will be increased.”Daniel 12:4

Instauratio Magna (1620)

“…that wisdom which we have derived principally from the Greeks is but like the boyhood of knowledge, and

has the characteristic property of boys:

“…it is but a device for exempting ignorance from ignominy.”

“…the end which this science of mine proposes is the invention not of arguments but of arts.”

“…not so much by instruments as by experiments …skilfully and artificially devised for the express purpose of determining the point in question.”

“restoration of learning and knowledge”

it can talk, but it cannot generate;”

Cf. “Correlation Energy” (Lect 11) , “Strain Energy” (Lect 32)

Astronomy

Horology

Meteorology

Cartography

Chemistry

Royal Society1662

Ac ne forte roges, quo me ..duce, quo lare tuter, Nullius addictus jurare in .. ..verba magistri Quo me cumque rapit .. .. .. ..tempestas, deferor hospes.

.. .. .. .. .. .. Horace (15 B.C.)Lest you ask who leads .. .. me, in what household .. I lodge, There is no master in .. .. .. whose words I am .. .. .. .. bound to take an oath, Wherever the storm .. .. .. .. forces me, there I put in .. as a guest.

“The Royal Society for the Improving of

Natural Knowledge by Experiments”

(the late)

Francis BaconViscount Brouncker

(President)N

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Crucial

www.bluestreetjazzband.com

“finally decides between two rival hypotheses, proving the one and

disproving the other”

cross = crux

Bacon’s most important kind of experiment:

ChapelTrinity College, Cambridge

Experimentum Crucis

Newton’s “Experimentum Crucis” (1666 -1672)

Proved (to Newton) that Light is a Substance, not Hooke’s pulses.

“Nec variat lux fracta colorem.”

“The broken light does not change

its color.”

How does the prism make color?

by altering pulses (à la Hooke & Descartes)

or by separating existing colors?

Experiments are indispensable in

organic chemistry (an empirical science)

but so is logic.Believe what I say only

when it makes sense to you.What if it doesn’t?

How to Succeed in Chem 125

Samuel Pepysas a Model

Science Student

Samuel Pepys (1633-1703)

Diary 1660-1669

Saw Charles Ibeheaded 1649

B.A. Cantab. 1654

“Clerk of the Acts”Navy Board 1660

Samuel Pepys (1633-1703)

July 4, 1662

…By and by comes Mr. Cooper, mate of the Royall Charles, of whom I intend to learn mathe-matiques, and do begin with him to-day, he being a very able man... After an hour's being with him at arithmetique (my first attempt being to learn the multiplication-table); then we parted till to-morrow.

Diary 1660-1669

Samuel Pepys (1633-1703) July 9, 1662

Up by four o'clock, and at my multiplicacion-table hard, which is all the trouble I meet withal in my arithmetique.

July 11, 1662

Up by four o'clock, and hard at my multiplicacion-table, which I am now almost master of…

December 25, 1662

…so to my office, practising arithmetique alone and making an end of last night's book with great content till eleven at night, and so home to supper and to bed

Motivated,Diligent

Samuel Pepys (1633-1703)

December 6, 1663 [Sunday]

…I below by myself looking over my arithmetique books and timber rule. So my wife rose anon, and she and I all the afternoon at arithmetique, and she is come to do Addition, Subtraction, and Multiplicacion very well, and so I purpose not to trouble her yet with Division...

Worked with study partner

Isaac Newton (1643-1727)

Six years later Pepys encountered a “problem” with Dice.

Pepys’s Problem (11/22/1692)A - has 6 dice in a Box, wth wch he is to fling a 6.

B - has in another Box 12 Dice, wth wch he is to fling 2 Sixes.

C - has in another Box 18 Dice, wth wch he is to fling 3 Sixes.

Q. whether B & C have not as easy a Taske as A, at even luck?

If the Question be thus stated, it appears by an easy computation that the expectation of A is greater then that of B or C, that is, the task of A is the easiest.

What is ye expectation or hope of A to throw every time one six at least wth six dyes? [etc.]

Newton’s Reply (11/26/1692)

But yet I must not pretend to soe much Conversation wth Numbers, as presently to comprehend as I ought to doe, all ye force of that wch you are pleas'd to assigne for ye Reason of it, relating to their having or not having ye Benefit of all their Chances

Pepys’s Reply (12/6/1692)

...You give it in favour of ye Expectations of A, & this (as you say) by an easy Computation.

. ; and therefore were it not for ye trouble it must have cost you; I could have wish'd for a sight of ye very Computation.

Not ashamed to admit whenhe didn’t really understandInsisted on proof

3103146656A 0.6651=

13467042112176782336B 0.6187=

Pepys “WHY?”"I cannot bear the Thought of being made Master of a Jewell

I know not how to wear."

“I never went to his office hours for help because I felt like he would make me feel stupid, because he is

superior to me in chemistry.” (from an anonymous end-of-semester course evaluation - Jan 2007)

Contrast with:

Willing to swallowhis pride in the search for solid understanding

Read Pepys & Newton and get together to do Problems for Monday.

Contribute to Wiki when asked.

Problems For Friday (optional): 1) Which two class members have rooms nearest you?2) What are the three most common items of advice from course veterans?

For Monday: Isotope problems from Pepys & Newton

For Friday (Sept. 12):1) Draw Lewis Structures for Functional Groups2) Are Lewis Structures correct?3) What do Lewis Structures show?

Isotope Ratio Mass Spectrometry

Wiki Assignments

Are There Atoms & Molecules?

What Force HoldsAtoms Together?

Springs?

http://demo.physics.uiuc.edu

Robert Boyle

Robert Boyle(1627-1691)

P V = constAir Pump built by his servant Robt. Hooke

1678

Hooke’s Law

Hooke’s Force LawF = -k x

Scale

Potential Energy

Force x

Hooke’s Law“Ut tensio

sic vis”

x2

extension

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ergy

End of Lecture 1Sept 3, 2008