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18 Jun Quiz grade summary For an indication of your standing in class, add the following number of points to the score appearing in the tally box of your quizzes:
  • Add 3 points to quiz # 1
  • Add 3 points to quiz # 2
  • Add 15 points to quiz # 3
  • Add 9 points to quiz # 4

These are your curved quiz scores. Now add up your curved quiz scores. Grade ranges are

>377 = A

377-346 = A-

346-331 = B+

331-284 = B

284-269 = B-

269-223 = C+

223-192 = C

192-146 = C-

146-116 = D

<116 = F

Sample calculation

Quiz # 1 = 77 + 3 = 80

Quiz # 2 = 69 + 3 = 72

Quiz # 3 = 59 + 15 = 74

Quiz # 4 = 72 + 9 = 81

Total = 80 + 62 + 74 + 81 = 307 = B

16 Jun Quiz # 4 Quiz # 4 is on W 18 Jun 12:00PM–1:00PM in SCI 113.

Bring a functioning scientific calculator to the exam.
There are questions requiring addition and subtraction on the quiz: you may use a stand-alone calculator, that is, it cannot be the calculator built into your phone or any other device. There are no spare calculators to lend you and you may not borrow another student's calculator.

Rules for taking exams

(1) Nothing is allowed on your desk except the exam, a pen, molecular models (which must be in a clear plastic bag), and a stand-alone scientific calculator. No books, papers, notes, laptops, cell phones, etc., are allowed on your desk. You may not refer to books or notes of any kind. Exams must be taken in ink.

A periodic table giving the symbol, atomic number, and electronegativity of each element is provided. Other information provided with the exam:

The following tables of IR frequencies and NMR chemical shifts are distributed with the quiz: familiarize yourself with the entries in the tables before the quiz so you're not trying to figure out how to use the tables during the quiz. You need not memorize any IR frequency or any NMR chemical shift, although doing so makes spectral analysis more rapid.

Table of IR frequencies

Stretch w [cm–1]
alcohol O–H 3650–3200
N–H 3500–3300
carboxylic acid O–H 3300–2500
Csp–H 3300
Csp2–H 3100
Csp3–H 2950
aldehyde Csp2–H 2700
C≡N 2260–2220
C≡C 2260–2100
C=O 1780–1650
C–N 1650
alkene C=C 1680–1600
benzene C=C 1600, 1500
(either or both)

Table of NMR chemical shifts

Type of hydrogen

d [ppm]

Type of hydrogen

d [ppm]

Type of hydrogen

d [ppm]

alcohol HO

variable

HCC

2–3

HCO

3.2–3.8

HN

variable

HCS

2.1–3.1

HC=C

4–7

HR

0.8–1.6

HC–Ph

2.2

H–Ph

6.5–8.5

HCC=C

1.6

HCN

2.2–2.8

HC=O

8–10

HCC=O

2.0–2.2

HCX

(X = Cl, Br, I)

2.2–4.2

acid HO

10–14

(2) All personal belongings (e.g., backpacks, clothing that you will not be wearing) are to be placed at the front of the room. You may not have any electronic devices (e.g., iPods, cell phones) other than a stand-alone calculator in your possession. Silence cell phones and disable the vibrator function. Do not wear hats, caps or headgear of any kind unless you do so for religious reasons.

(3) Do not look at anyone else's exam. Cases of suspected cheating are referred to the Academic Conduct Committee, which investigates and takes appropriate action. The maximum sanction is expulsion from the University.

(4) There is no talking to other students or sharing of any materials such as writing instruments or molecular models. If you arrive late to the examination hall, you will not be given additional time to complete the exam. Refrain from eating, drinking, and asking to go to the restroom.

(5) Do not sit for the exam if you are ill, sneezing or coughing. Do not sit for the exam if you are psychologically unprepared to complete it. Once the exam is distributed, you are officially taking the exam and whatever score you attain stands.

(6) If you miss the exam, the score you earn on the final exam is counted as the score of the exam you missed.

(7) If you finish the exam early, hand it in and leave the examination hall with the minimum disturbance. Do not congregate in the common area immediately outside the examination hall waiting for your friends.

(8) Exams are returned at the next lecture following the exam. Please attend to pick up your exam. An answer key is posted on the Exams page of this website. You may request that the exam be regraded if you suspect errors in grading. The exam in dispute, accompanied by a note explaining the nature of the grading issue, must be submitted to the lecturer no later than the Tuesday after the exam is returned. This is a firm deadline. Exams taken in pencil and answers written on the back of exam pages are not accepted for regrading.

Learning goals and skills

• Understand when to expect complex splitting.
• Be able to predict the splitting pattern of a complex-splitting multiplet (i.e., dt, tt, dq, dddd, etc.).
• The only complex splitting multiplet whose shape you should be able to recognize is the doublet of doublets (dd): understand when a signal will be split into a dd and be aware of the fact that a dd can look like a triplet, a doublet, or even a singlet depending on the values of the coupling constants (i.e., the spacings within the dd).
• Be aware of the fact that a complex-splitting multiplet may look like a simple-splitting N + 1 rule multiplet depending on the values of the coupling constants.
• Understand what is meant by integration in NMR spectroscopy; given an integrated NMR spectrum, be able to determine the number of hydrogens giving rise to each signal.
• Given a compound's formula and NMR spectrum, be able to deduce the structure of that compound.
• Be able to deduce the structure of the product of a reaction by integrating chemical information and NMR spectroscopic data.

Reactions: Generalities
• Understand what is meant by a reaction mechanism.
• Understand what a transition state is and what an intermediate is and how they differ.
• Given a reaction mechanism, be able to construct its energy diagram.
• Understand what a nucleophile is and what an electrophile is; be able to identify nucleophiles, electrophiles, and molecules that are neither nucleophiles nor electrophiles.
• Be able to calculate the overall energy change of a reaction from bond-energy data.

Exam questions dealing with specific reactions mostly involve being able to predict the product of a reaction and being able to write out the mechanism by correctly employing the curved-arrow convention.

Acids and bases
Be able to identify acids and bases in a chemical equation; be able to predict the products of an acid–base reaction.
• Understand the factors that influence acid and base strength: (1) the periodic table trends (i.e., acidity increases left-to-right across a row and acidity increases down a column); (2) the inductive effect (i.e., electron-withdrawing groups increase acidity); (3) the resonance effect (i.e., delocalization of negative charge decreases basicity).
• Be able to rank a set of molecules by acidity or basicity.
• Be able to identify the most acidic proton in a molecule.
• Understand what a Ka is, what a pKa is, how they are related, the significance of a large (or small) Ka, and the significance of a positive (or negative) pKa.
• Memorize the pKa of the protons in the following chemical environments.

• Be able to calculate the equilibrium constant Keq of an acid-base reaction using the Henderson-Hasselbalch equation Keq = 10^(pKa(HB+) - pKa(HA)). You need not memeorize this equation; you do need to know what the variables mean and how to interpret the result of a Henderson-Hasselbalch calculation.
• Be able to predict the dominant form of an acid or a base at a given pH.

Reactions of alkenes
The only alkene reaction on the quiz is hydrohalogenation:
alkenes + HX (X = halogen). Be able to predict the major product and write mechanisms. Be aware that the intermediate is the most stable possible carbocation (i.e., the reaction exhibits Markovnikov regioselectivity) and that rearrangements are possible.

Carbocations
• Understand what a carbocation is and understand the factors that influence carbocation stability: (1) the degree of substitution (i.e., 3º > 2º > 1º > 0º); (2) the inductive effect (i.e., electron-withdrawing groups destabilize carbocations); (3) the resonance effect (i.e., electron-donation by resonance stabilizes carbocations).
• Be able to rank a set of carbocations by stability.
• Understand what a carbocation rearrangement is, when they are likely to happen, and be able to correctly employ the curved-arrow convention to write mechanisms involving carbocation rearrangements.
• Be aware of the possibility of the formation of unexpected products due to the intervention of carbocation rearrangements.

Textbook and on-line lecture note coverage

NMR: Complex splitting
Chapter 13.9

NMR: Structure determination
Chapter 13.12

Acids and bases
Chapter 4.1–4.6

Reactions: Generalities, hydrohalogenation
Chapter 6.1–6.3.A

NMR spectroscopy
Chapter 13.1–13.10

On-line lecture notes 15-18.

Good luck and happy studying!

9 Jun Quiz # 3 Quiz # 3 is on W 11 Jun 12:00PM–1:00PM in SCI 113.

Rules for taking exams

(1) Nothing is allowed on your desk except the exam, a pen, and molecular models (which must be in a clear plastic bag). No books, papers, notes, laptops, cell phones, calculators, etc., are allowed on your desk. You may not refer to books or notes of any kind. Exams must be taken in ink.

A periodic table giving the symbol, atomic number, and electronegativity of each element is provided. Other information provided with the exam:

The following tables of IR frequencies and NMR chemical shifts are distributed with the quiz: familiarize yourself with the entries in the tables before the quiz so you're not trying to figure out how to use the tables during the quiz. You need not memorize any IR frequency or any NMR chemical shift, although doing so makes spectral analysis more rapid.

Table of IR frequencies

Stretch w [cm–1]
alcohol O–H 3650–3200
N–H 3500–3300
carboxylic acid O–H 3300–2500
Csp–H 3300
Csp2–H 3100
Csp3–H 2950
aldehyde Csp2–H 2700
C≡N 2260–2220
C≡C 2260–2100
C=O 1780–1650
C–N 1650
alkene C=C 1680–1600
benzene C=C 1600, 1500
(either or both)

Table of NMR chemical shifts

Type of hydrogen

d [ppm]

Type of hydrogen

d [ppm]

Type of hydrogen

d [ppm]

alcohol HO

variable

HCC

2–3

HCO

3.2–3.8

HN

variable

HCS

2.1–3.1

HC=C

4–7

HR

0.8–1.6

HC–Ph

2.2

H–Ph

6.5–8.5

HCC=C

1.6

HCN

2.2–2.8

HC=O

8–10

HCC=O

2.0–2.2

HCX

(X = Cl, Br, I)

2.2–4.2

acid HO

10–14

(2) All personal belongings (e.g., backpacks, clothing that you will not be wearing) are to be placed at the front of the room. You may not have any electronic devices (e.g., iPods, cell phones) in your possession. Silence cell phones and disable the vibrator function. Do not wear hats, caps or headgear of any kind unless you do so for religious reasons.

(3) Do not look at anyone else's exam. Cases of suspected cheating are referred to the Academic Conduct Committee, which investigates and takes appropriate action. The maximum sanction is expulsion from the University.

(4) There is no talking to other students or sharing of any materials such as writing instruments or molecular models. If you arrive late to the examination hall, you will not be given additional time to complete the exam. Refrain from eating, drinking, and asking to go to the restroom.

(5) Do not sit for the exam if you are ill, sneezing or coughing. Do not sit for the exam if you are psychologically unprepared to complete it. Once the exam is distributed, you are officially taking the exam and whatever score you attain stands.

(6) If you miss the exam, the score you earn on the final exam is counted as the score of the exam you missed.

(7) If you finish the exam early, hand it in and leave the examination hall with the minimum disturbance. Do not congregate in the common area immediately outside the examination hall waiting for your friends.

(8) Exams are returned at the next lecture following the exam. Please attend to pick up your exam. An answer key is posted on the Exams page of this website. You may request that the exam be regraded if you suspect errors in grading. The exam in dispute, accompanied by a note explaining the nature of the grading issue, must be submitted to the lecturer no later than the Tuesday after the exam is returned. This is a firm deadline. Exams taken in pencil and answers written on the back of exam pages are not accepted for regrading.

Learning goals and skills

• Understand what is meant by "resolution of enantiomers" and be able to describe how a pair of enantiomeric acids or bases could be separated.
• Understand what is meant by "optical activity" and be able to recognize molecules that exhibit optical activity.
• Understand what is meant by a "racemic mixture".
• Understand how to calculate the percentage of an enantiomer in a mixture. You do not need to memorize the equation for doing so, that is

(1 + (alpha(mix)/alpha(pure))) * 50%

but you do need to know how to use it.
• Understand the meaning of the symbols "(+)", "(–)", and "(±)" in use with optically active and inactive samples.
• Understand what is meant by a "meso compound" and be able to recognize meso compounds.
• Understand the factors that effect the frequency of an IR absorption.
• Given a menu of molecules and IR spectra, be able to match each molecule with its IR spectrum.
• Understand the factors that determine a proton's chemical shift, that is, the electronegativity effect and diamagnetic anisotropy (the ring current) and recognize that these effects are cumulative and additive.
• Be able to make a good (±1 ppm) guess at a proton's chemical shift.
• Understand how protons can exhibit the same chemical shift because of symmetry, because of the operation of a rapid mechanism, and because of accidental equivalence.
• Recognize the effect of a chirality center on the chemical shifts of the protons of a methylene (CH2) group.
• Understand when to expect simple (N + 1 Rule) splitting.
• Know what the simple NMR multiplets (singlet, doublet, triplet, etc.) look like.
• Understand what accidental chemical-shift equivalence is and its impact on the appearance of NMR spectra. (i.e., protons that should theoretically split each other's signals do not in practice.)
• Be able to sketch the NMR spectrum of a compound given that compound's structure.
• Given a menu of molecules and NMR spectra, be able to match each molecule with its NMR spectrum.

Textbook and on-line lecture note coverage

meso Compounds
Chapter 3.4.B

Optical activity
Chapter 3.7

Resolution of enantiomers
Chapter 3.9

IR spectroscopy
Chapter 12.1–12.5

NMR spectroscopy
Chapter 13.1–13.10

On-line lecture notes 10-14.

Good luck and happy studying!

2 Jun Quiz # 2 Quiz # 2 is on W 4 Jun 12:00PM–1:00PM in SCI 113.

Bring a functioning scientific calculator to the exam.
The calculator must be a stand-alone model, that is, it cannot be the calculator built into your phone or any other device. It must be able to handle numbers in scientific notation and be able to exponentiate e (2.718282...) to an arbitrary power. There are no spare calculators to lend you and you may not borrow another student's calculator.

Rules for taking exams

(1) Nothing is allowed on your desk except the exam, a pen, molecular models (which must be in a clear plastic bag), and a stand-alone scientific calculator. No books, papers, notes, laptops, cell phones, etc., are allowed on your desk. You may not refer to books or notes of any kind. Exams must be taken in ink. A periodic table giving the symbol, atomic number, and electronegativity of each element is provided. Other information provided with the exam:
• The numerical values of selected strain interactions
• The Eyring equation
• the mathematical definition of a thermodynamic equilibrium constant (Keq = e–∆Gº/RT
• Selected ∆Hºf values.

(2) All personal belongings (e.g., backpacks, clothing that you will not be wearing) are to be placed at the front of the room. Other than a stand-alone scientific calculator you may not have any electronic devices (e.g., iPods, cell phones) in your possession. Silence cell phones and disable the vibrator function. Do not wear hats, caps or headgear of any kind unless you do so for religious reasons.

(3) Do not look at anyone else's exam. Cases of suspected cheating are referred to the Academic Conduct Committee, which investigates and takes appropriate action. The maximum sanction is expulsion from the University.

(4) There is no talking to other students or sharing of any materials such as writing instruments or molecular models. If you arrive late to the examination hall, you will not be given additional time to complete the exam. Refrain from eating, drinking, and asking to go to the restroom.

(5) Do not sit for the exam if you are ill, sneezing or coughing. Do not sit for the exam if you are psychologically unprepared to complete it. Once the exam is distributed, you are officially taking the exam and whatever score you attain stands.

(6) If you miss the exam, the score you earn on the final exam is counted as the score of the exam you missed.

(7) If you finish the exam early, hand it in and leave the examination hall with the minimum disturbance. Do not congregate in the common area immediately outside the examination hall waiting for your friends.

(8) Exams are returned at the next lecture following the exam. Please attend to pick up your exam. An answer key is posted on the Exams page of this website. You may request that the exam be regraded if you suspect errors in grading. The exam in dispute, accompanied by a note explaining the nature of the grading issue, must be submitted to the lecturer no later than the Tuesday after the exam is returned. This is a firm deadline. Exams taken in pencil and answers written on the back of exam pages are not accepted for regrading.

Learning goals and skills

• Be able to calculate the strain energy of a molecule drawn in Newman projection. The numerical values of selected strain interactions will be given: you need not memorize the numerical value of any strain interaction, but you do need to know how to work with these values.
• Be able to calculate the rate constant k of a conformational change using the Eyring equation. The Eyring equation will be given: you need not memorize it. The Eyring equation is not given in the textbook: consult on-line lecture notes.
• Be able to translate a cyclohexane derivative presented as a wedge-and-dash structure to a chair conformation.
• Understand what is meant by the cyclohexane "chair flip" and be able to draw three-dimensionally accurate representations of the two interconverting chair conformations of cyclohexane and of substituted cyclohexanes.
• Be able to calculate the strain energy of a chair conformation. The numerical values of selected strain interactions will be given: you need not memorize the numerical value of any strain interaction, but you do need to know how to work with these values.
• Be able to calculate the percentage of each of two interconverting chair conformations. To do so, you need to be able to work with the mathematical definition of a thermodynamic equilibrium constant (Keq = e–∆Gº/RT). You need not memorize this equation, but you do need to know how to work with it.
• Understand what a homodesmotic reaction is and be able to set up homodesmotic reactions. Homodesmotic reactions are not covered in the textbook; refer to on-line lecture notes.
• Be able to calculate the strain energy of cyclic alkanes and alkenes using homodesmotic reactions. You need not memorize the standard enthalpy of formation ∆Hºf of any molecule; you do need to know how to work with such values.
• Be able to calculate degrees of unsaturation (DOU; memorize the formula given at lecture) and understand the meaning of DOU.
• Understand what is meant by "constitutional isomers" and be able to determine whether or not two compounds are constitutional isomers.
• Given the formula of a compound, be able to draw several constitutional isomers corresponding to that formula.
• Understand the definition of "chirality"; be able to identify whether a structure is chiral or not.
• Be able to determine the number and kind of symmetry elements (i.e., a center, plane, or axis of symmetry) present in a molecule. Your textbook does not cover the center of symmetry or the axis of symmetry and does a pitiful job of covering the plane of symmetry: refer to the on-line version of the lecture notes for a more complete treatment.
• Understand the definition of "stereoisomer", "enantiomer", and "diastereomer"; be able to apply these terms.
• Know what a chirality center is and be able to identify chirality centers in molecules.
• Be able to specify the absolute configuration (R or S) of a chirality center.

Textbook and on-line lecture note coverage

Conformational analysis
Chapter 2.5, 2.6

Constitutional isomers
Chapter 2.2

Stereochemistry
Chapter 3.1–3.6

On-line lecture notes 4-9.
Note about lecture note 9: Stop when you get to "Resolution of enantiomers".

Good luck and happy studying!

22 May Quiz # 1 Quiz # 1 is on W 28 May 12:00PM–1:00PM in SCI 113.

Rules for taking quizzes

(1) Nothing is allowed on your desk except the quiz, a pen, and molecular models, which must be in a clear plastic bag. No books, papers, notes, laptops, cell phones, etc., are allowed on your desk. You may not refer to books or notes of any kind. A periodic table and scratch paper are provided. Quizzes must be taken in ink.

(2) All personal belongings (e.g., backpacks, clothing that you will not be wearing) are to be placed at the front of the room. You may not have any electronic devices (e.g., iPods, cell phones) in your possession. Silence cell phones and disable the vibrator function. Do not wear hats, caps or headgear of any kind unless you do so for religious reasons.

(3) Do not look at anyone else's quiz. Cases of suspected cheating are referred to the Academic Conduct Committee, which investigates and takes appropriate action. The maximum sanction is expulsion from the University.

(4) There is no talking to other students or sharing of any materials such as writing instruments or molecular models. If you arrive late to the examination hall, you will not be given additional time to complete the quiz. Refrain from eating, drinking, and asking to go to the restroom.

(5) Do not sit for the quiz if you are ill, sneezing or coughing. Do not sit for the quiz if you are psychologically unprepared to complete it. Once the quiz is distributed, you are officially taking the quiz and whatever score you attain stands.

(6) If you finish the quiz early, hand it in and leave the examination hall with the minimum disturbance. Do not congregate in the common area immediately outside the examination hall waiting for your friends.

(7) Quizzes are returned at the next lecture following the quiz. Please attend to pick up your quiz. An answer key is posted on the Exams page of this website. You may request that the quiz be regraded if you suspect errors in grading. Quizzes taken in pencil and answers written on the back of quiz pages are not accepted for regrading. The quiz in dispute, accompanied by a note explaining the nature of the grading issue, must be submitted to the lecturer no later than the Monday after the quiz is returned. This is a firm deadline.

Textbook and on-line lecture note coverage

Functional groups
Chapter 1.3

Notation
Chapter 2.2–2.4
The text does a poor job of describing notation. Scan the sections in Chapter 2 listed above for the correspondence between Lewis structures and bond–line (line–angle) notation. Better yet, refer to on-line lecture note 2.

Nomenclature
Scattered throughout the book; refer to on-line lecture note 3.

Conformational analysis
Chapter 2.5.A

On-line lecture notes 1-4.
Note: The only section of on-line lecture note 4 covered on the quiz is the section entitled "Newman projections"; stop when you get to "Conformational analysis of butane".

Learning goals and skills

• Be able to identify the following functional groups: carboxylic acids, esters, amides, nitriles, aldehydes, ketones, alcohols, thiols, amines, alkenes, arenes, alkynes, ethers, sulfides (thioethers), organic halides and organic nitro compounds. Some of these functional groups can be classified as 0º, 1º, 2º, 3º, etc., monosubstituted, disubstituted, etc.; be able to apply these distinctions.
• Know what is meant by a methyl, methylene, and methine group.
• Be able to write and interpret condensed, bond-line, and dash-and-wedge structures.
• Be able to write a compound's structure from its systematic name.

• Understand what is meant by molecular strain and be aware of the different types of strain (bond-length, angle, torsional, steric).
• Understand what a Newman projection is and be able to draw staggered and eclipsed Newman projections of a compound.

Good luck and happy studying!


Posted 17 Jun 2014

This page is maintained by Bruno I. Rubio