CH341-01/CH540, Exam 1, Fall 2009
______________________________________
Name
This exam consists of several parts of unequal difficulty. Look over the whole exam right now, and start
on something you know well. If you don’t know something, skip it, and come back to it later. Use your
time wisely.
Keep Your Eyes On Your Own Paper!
Grading Summary
Page 2. _______________ (16)
Page 6. _______________ (23)
Page 3. _______________ (14)
Page 7. _______________ (17)
Page 4. _______________ (12)
Bonus! _______________ (≤5)
Page 5. _______________ (18)
Total ________________ (100)
A Partial Periodic Table of the Elements
1A
IIA
IIIB
IVB
VB
VIB
VII
B
VIII
IB
IIB
IIIA
IVA
VA
VIA
VII
A
1
H
VIII
A
2
He
1.01
4.00
3
Li
4
Be
5
B
6
C
7
N
8
O
9
F
10
Ne
6.94
9.01
10.8
12.0
14.0
16.0
19.0
20.2
11
Na
12
Mg
13
Al
14
Si
15
P
16
S
17
Cl
18
Ar
23.0
24.3
27.0
28.1
31.0
32.1
35.5
40.0
19
K
20
Ca
31
Ga
32
Ge
33
As
34
Se
35
Br
36
Kr
39.1
40.1
69.7
72.6
74.9
79.0
79.9
83.8
37
38
49
50
51
52
53
I
54
21
22
23
24
25
26
27
28
29
30
39
40
41
42
43
44
45
46
47
48
127
2
1. Expand the following condensed structure. Show all atoms, all bonds, and all unshared pairs of
electrons. No atoms are charged.
NCCH2COCH3
2. Draw two structures that correspond to the formula C2H5NO2. Show all atoms, bonds, and unshared
pairs of electrons. No atoms may be charged. One structure must contain one ring, and the other
structure must not contain any rings.
3. Draw one important resonance form of the following structure. Use curved arrows to show how
electrons would have to move to get from the original structure to the one you drew.
O
N
C
H
C
C
CH3
3
4a. Complete the following acid-base reaction. Draw curved arrows to show how bonds are broken and
formed.
S
H + H3C
N
CH3
CH3
Benzenethiol
TMA
4b. The pKa of benzenethiol is 7. The pKa of the conjugate acid of TMA is 11. Which side of the above
reaction is favored at equilibrium? Explain your reasoning.
5. Circle and label neatly each occurrence of the following functional groups in the structure below.
Alkene
Alkyne
Carboxylic acid
O
Ether
Ester
CH2
Aromatic
O
OH
C
CH
CH
C
CH
CH
C
HN
C
CH
CH
O
Ketone
Aldehyde
CH2
CH
C
Amine
Amide
H2C
C
CH2
Alcohol
CH
CH2
C
CH
CH3
CH
4
6. Multiple Choice: Choose the best answer to each question.
1.
_________
2.
_________
3.
How many pi-bonds are in the structure below?
C
N
A. 0
B. 1
C. 2
D. 3
When one compares the densities of hexane and water, one finds:
A. Hexane is less dense than water.
B. Hexane and water have the same density.
C. Hexane is more dense than water.
D. The relative densities of two immiscible liquids cannot be measured.
If a mixture contains 80% of one compound, and 20% of its enantiomer, then the optical
purity (enantiomeric excess) of the mixture is?
A. 100%
B. 80%
C. 60% D. 20%
_________
4.
Which line-angle formula corresponds to the condensed structure below?
HOCH2C(O)CH(CH3)2
A.
B.
C.
D.
_________
H
O
HO
5.
HO
HO
O
O
O
O
Which of the following is a diastereomer of the structure below?
CH3
CH3
_________
A.
H3 C
B.
C.
CH3
H3 C
6.
D.
CH3
CH3
CH3
H3C
CH3
Which of the following structures has the highest boiling point?
A.
_________
O
H 2C
CH2
CH2 CH2
B.
H2 C
CH2
H2 C
CH
C.
H2C
H2C
O
H
CH2
CH
D.
H 2C
H 2C
CH3
CH2
CH
NH2
5
7. What are the indicated bond angles and hybridization states in the following molecule? The angles in
the drawing may not be accurate, since the molecule is really 3-Dimensional.
E
H3C
B
H3C
C
C
C
C
CH2
D
C
C
H3C
A
CH3
O
F
Bond Angles
Hybridization States
A:
D:
B:
E:
C:
F:
8. Draw the two chair forms of following structure. Label the groups in each form as either equatorial or
axial. Which form is more stable? Why
H
F
CH2CH2CH3
H
6
9. What is the IUPAC name of each of the following structures?
a.
H
F
CH2CH2CH3
H
b.
CH3
CH2
H3C
CH
CH2
CH
CH2
CH3
Cl
c.
CH2CH2CH2CH3
H3C
CH3
CH
HC
H3C
CH3
d. H3C
CH2
CH
CH2
CH2
CH3
CH
CH2
CH
H3C
H3C
CH3
Classify the indicated atom as either R or S.
Br
H
HO
C
CH2
CH2
CH2
CH3
CH2
7
10. Star (*) all of the chirality centers in the following structure.
H3C
CH
CH2
H2C
CH2
CH3
CH
CH
CH2
H3C
CH
CH
CH2
CH3
Cl
11. Classify each pair of structures below as identical, constitutional isomers, enantiomers, or
diastereomers.
a.
H
Br
Br
H
C
H3C
b.
C
CH2
C
H3C
c.
CH3
Br
H
C
H3C
C
CH2
CH3
Br
CH2
CH3
CH2
CH2
CH2
CH3
H2C
H3C
and
Br
Br
H
H
H
and
H3C
CH2
CH2
C
H
CH2
CH2
CH2
C
C
H3C
and
C
H2C
CH2
CH2
C
CH2
CH3
H
H
H
CH3
8
Bonus:
The most stable chair conformation of the following molecule has the OH in an axial position. Explain
why.
O
O
O
H