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Name: _______________________________________________________________________ Last First MI Section # _____________

Equation:

ΔG0 = −RT ln Keq • ΔG0 = Change in

Gibbs free energy • Keq = Equilibrium

constant • T = Temperature in

kelvins • R = Universal gas

constant that has the value 8.314 J (1.987 cal)·K−1·mol−1

Energy values: H/H eclipsed is 1.0 kcal/mol, CH3/H eclipsed is 1.3 kcal/mol, CH3/CH3 eclipsed is 3.0 kcal/mol, CH3/CH3 gauche is 0.9 kcal/mol

Electronegativity Values: F 4.0 O 3.5 N 3.0 Cl 3.0 Br 2.8 C 2.5 S 2.5 I 2.5 P 2.1 H 2.1

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Name: _______________________________________________________________________ Last First MI Section # _____________

Grading Page (Exam 1):

Page Points Possible Points Earned

Multiple Choice (3-6) 45

7 10

8 10

9 5

10 30

TOTAL 100

Honor: 11-12 20

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Multiple Choice Choose the one best answer for each of the following questions. Using a pencil, record each answer on the provided Scantron sheet. You should also circle each answer directly on the exam (3 points each)

1. Which of the following statements about enantiomers is false?

a. They have identical melting points b. They have identical boiling points c. The magnitude of their specific rotations is identical d. They have identical densities e. They react at the same rate with optically active reagents

2. Which of the molecules given below are achiral?

a. A and C b. A and E c. B and C d. B and D e. D and E

3. Which of the following are meso compounds?

a b c d e

4. How many stereogenic centers are present in the following molecule?

a. 0 b. 1 c. 2 d. 4 e. 7

E

OH OH

OHOH

A B C D

H

CH3

HO

HO

CH3

H

OH

O

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5. Which of the following is the least stable chair conformation for the compound shown below?

a b c d

6. What is the index of hydrogen deficiency of a compound formula: C7H7NO?

a. 0 b. 1 c. 2 d. 3 e. 4

7. What functional groups are most likely present in a compound whose IR spectrum shows absorbances at 1648 and 2217cm-1?

a. Aldehyde and alkene b. Alkene and alcohol c. Alcohol and nitrile d. Alkyne and ketone e. Alkene and nitrile

8. Which C=O has a higher stretching frequenies?

9. Which of the following C6H12O isomers would be expected to produce an m/z peak at M+−18?

a b c d

10. Which of the following compounds will give a molecular ion having m/z = an odd number?

O O OH

O

a b

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a. CH2BrCl b. CH3CO2H c. CH3CH2NH2 d. (CH3)2NCH2C≡N

11. Order the following protons from lowest to highest chemical shift value

a b c d

a. Ha < Hc < Hb < Hd b. Ha < Hc < Hd < Hb c. Hc < Ha < Hd < Hb d. Hc < Ha < Hb < Hd e. Hc < Hd < Ha < Hb

12. What is the relationship between Ha and Hb in the following compound?

a. Chemically unrelated b. Homotopic c. Enantiotopic d. Diastereotopic e. None of these

13. Which of the following molecules best fits the following 13C-NMR data? 13C-NMR data: 20, 22, 32, 44, and 67 ppm

a b c d

HbO

Ha

HdHc

ClHa

Hb

HO

H3C

CH3 HO

H3C

CH3 HO

H3C CH3

HO

H3CCH3

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14. Which of the following molecules best fits the following NMR spectrum?

a b c d e

15. Combustion analysis of an organic compound shows it to be 64.3% carbon. It displays a molecular ion at m/z=112 amu in the mass spectrum. Which of the following is a plausible molecular formula for this compound?

a. C8H16 b. C7H12O c. C6H8O2 d. C5H4O3

O

OOH

OH

OH

OH

HO

HO

HO

HO

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Completion Section

16-20 (5 points each) The molecular formulas and 1H NMR spectra of common organic solvents are provided below and on the following 2 pages. For each, neatly draw the entire structure (i.e., not the acronym) in the box provided. In some cases, relative integration values (circled numbers) and/or other information have been provided.

Note: Do not represent functional groups with partial molecular formulas or other abbreviations. For example, do not use “Ph” or “C6H5” for a phenyl group. Draw the entire group (including hydrogen atoms).

16.

17.

8

18.

19.

9

20. Propose a structure that comply with the 1H-NMR spectrum as shown (formula of the compound is C6H12O2):

C6H12O2

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21. (30 points total) Answer the questions below about the structure that has the following data:

EA C, 75.69; H, 8.80 M+ 206 IR 3430 (broad), 1705 (strong) 13C NMR 181.4, 140.9, 137.0, 129.5, 127.4, 45.9, 44.1, 30.3,

22.5, 18.2 1H NMR 11.9 (broad s, 1H), 7.21 (d, J = 7.7, 2H), 7.09 (d, J =

7.7, 2H), 3.70 (q, J = 7.0, 1H), 2.44 (d, J = 6.8, 2H), 1.84 (nonet (9 lines), J = 6.8, 1H), 1.49 (d, J = 7.0, 3H), 0.89 (d, J = 6.8, 6H)

a. (7 points) Determine the molecular formula. Circle your final answer.

b. (5 points) Calculate the Index of Hydrogen Deficiency (IHD). Circle your final answer.

c. (8 points) Which protons are coupled to which? Complete the tables below using the NMR data above. Write H1, H2, etc. or “none”, as appropriate, in the box provided, and list all protons to which a given proton is coupled.

d. (10 points) Draw all of the possible enantiomers and diastereomers of the unknown compound that are consistent with all the data given. Circle your final answers.

e. (Extra credit – 5 points total) What is the common name of this over-the-counter pharmaceutical (3 points), and for which symptoms is it indicated (2 points)?

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Honor:

(20 points total) Answer the questions below about the structure that has MW = 107 and the following NMR spectra:

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a. (10 points) Determine the molecular formula of this compound. Circle your final answer.

b. (5 points) Calculate the Index of Hydrogen Deficiency (IHD) of this compound. Circle your final answer.

c. (5 points) Draw the structure of the unknown compound. Circle your final answer.

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14

15

16