Exam 5

2
Chemistry 1304
Exam 5 (105 points)
Name (please print)
May 4, 2015
Circle ONLY the LETTER of your answer. (3 points each)
1. Polonium-208 is an alpha emitter with a half-life of 2.90 years. How many milligrams of polonium
from an original sample of 2.00 mg will remain after 8.00 years?
a.
1.90 mg
d.
0.147 mg
b.
0.725 mg
e.
0.296 mg
c.
6.77 mg
f.
none of these
2. Decay of silicon-27 by positron emission yields
a.
magnesium-23.
d.
aluminum-27.
b.
sulfur-31.
e.
phosphorus-27.
c.
silicon-26.
f.
none of these
3
3. Estimate the age of a bottled wine that has a tritium, H, content 60% that of freshly bottled wine.
Tritium decays by beta decay and has a half-life of 12.3 yr.
3
1
H → 23 He + −01β
a.
35 yr
d.
16 yr
b.
9.1 yr
e.
7.4 yr
c.
0.029 yr
f.
none of these
4. Which of the following is(are) true for generating electricity by nuclear power?
a.
no new nuclear power plants are
being built
d.
lower natural gas prices have put the
economic viability of nuclear power
plants in doubt.
b.
the world's largest producer of
electric power is China
e.
b and d
c.
current nuclear power plants use
"light" water
f.
c and d
5. The primary difference(s) between a nuclear and coal or natural gas powered plants is(are)
a.
the type of turbine
d.
the method of distributing the power
b.
the size of the cooling towers
e.
all of the above
c.
the source of heat to generate steam
f.
none of these
6. Breeder reactors
a.
b.
c.
d.
e.
f.
7.
(3 points)
use Pu-230 that is recovered from the fission of U-238
are long tubes or tunnels used to separate U-238 from U-235
are the primary type of reactor in France
are not used in the US because of the danger terrorists acquiring the fuel and using it for
making bombs
all of the above
a, c, and d
Complete and balance the following reaction.
1
0n +
235
92
U
1
→ 3 0 n +
87
35
Br +
3
8. (7 points) The following questions pertain to the structure shown
on the right. The small numbers next to the formula identify the
individual atoms for reference in the following questions.
2
CH3
O
N
3
C
4
CH2=CH
1
a. Insert any lone electron pairs that are not shown on the structure
b. What is the hybridization at each of the following atoms?
C2
c.
C3
C4
N
What are the approximate bond angles around each of the following centers?
C1
N
9. (8 points) Draw the complete, fully expanded structure showing all atoms, including hydrogen, and all
bonds in for each of the following compounds
benzoic acid
acetone
10. (6 points) Write the semi-condensed structural formulas for each of the following compound (show
all important angles)
phenyl acetate
5-bromo-cis-2-methyl-3-hexene
11. (5 points) Draw semi-condensed structural formulas for all possible isomers of C3H8O.
12. (8 points) Write the complete, systematic name of each of the following compounds.
O
CH3
CH CH2
CH
CH2CH3
C
C
CH3
N
13. (4 points) CIRCLE ALL the asymmetric atoms in the compounds in the problem above.
CH3
C O C CH3
O
CH3
4
14. (8 points) Write complete structural formulas of the polymer produced from the following monomers.
In the blank, indicate whether the polymerization process is addition, condensation, or ring-opening.
CH3
O
CH3
type of polymerization:
NH2
HOOC
type of polymerization:
15. (12 points) Retrosynthesis is a planning process of working backwards from a desired target molecule
and determining which reactants can be used to make the molecule. This is usually a multistep
process and is used to design pathways to complex, bioactive molecules. In the cases below, you
need to use only one step. Show all of the starting molecules, and give any other reactants and
conditions (H+, heat ∆, etc.) needed to make the product shown on the right for FOUR of the following
five reactions. Write OMIT over the one you wish to skip or I will simply grade the first
four regardless of which ones are correct!
a.
O
O
O
O
O
O
CH3
b.
c.
Cl
CH3
CH3CH2
NH2+ClCH3
d.
CH2
O
CH3
H
e.
CH3
N
CH3
C
O
5
16. (21 points) Draw complete structural formulas for products of the reaction sequence shown below .
You may write either fully or partially condensed formulas as long as the molecular structure, including
the positions of functional group, is clearly shown. The full formula of the starting compound A is
C7H12O. [Note that it is often helpful to show all atoms, including H at the site of the reaction.]
H
C
O
[O]
A
"H2"
B
+ HBr
+ 2-propanol
E
H+ ∆
F
C
+ NaOH
- 2-propanol
G
+ HBr
D
+ NaOH
H (an isomer of F)
B
2
Chemistry 1304
Exam 5 (100 points)
Name (please print)
May 4, 2015
Circle ONLY the LETTER of your answer. (3 points each)
1. Polonium-208 is an alpha emitter with a half-life of 2.90 years. How many milligrams of polonium
from an original sample of 2.00 mg will remain after 8.00 years?
a.
1.90 mg
d.
0.147 mg
b.
0.725 mg
e.
0.296 mg
c.
6.77 mg
f.
2. Decay of silicon-27 by positron emission yields
a.
magnesium-23.
d.
aluminum-27
b.
sulfur-31.
e.
phosphorus-27.
c.
silicon-26.
f.
3
3. Estimate the age of a bottled wine that has a tritium, H, content 60% that of freshly bottled wine.
Tritium decays by beta decay and has a half-life of 12.3 yr.
3
1
H → 23 He + −01β
a.
35 yr
d.
16 yr
b.
9.1 yr
e.
7.4 yr
c.
0.029 yr
f.
4. Which of the following is(are) true for generating electricity by nuclear power?
a.
no new nuclear power plants are
being built
d.
lower natural gas prices have put the
economic viability of nuclear power
plants in doubt.
b.
the world's largest producer of
electric power is China
e.
b and d
c.
current nuclear power plants use
"light" water
f.
c and d
5. The primary difference(s) between a nuclear and coal or natural gas powered plants is(are)
a.
the type of turbine
d.
the method of distributing the power
b.
the size of the cooling towers
e.
all of the above
c.
the source of heat to generate steam
f.
none of these
6. Breeder reactors
a.
b.
c.
d.
e.
f.
7.
(3 points)
use Pu-230 that is recovered from the fission of U-238
are long tubes or tunnels used to separate U-238 from U-235
are the primary type of reactor in France
are not used in the US because of the danger terrorists acquiring the fuel and using it for
making bombs
all of the above
a, c, and d
Complete and balance the following reaction.
1
0n +
235
92
U
1
→ 3 0 n +
6
87
35
Br +
3
8. (7 points) The following questions pertain to the structure shown
on the right. The small numbers next to the formula identify the
individual atoms for reference in the following questions.
2
CH3
O
N
3
C
4
CH2=CH
1
a. Insert any lone electron pairs that are not shown on the structure
b. What is the hybridization at each of the following atoms?
C2
c.
C3
C4
N
What are the approximate bond angles around each of the following centers?
C1
N
9. (8 points) Draw the complete, fully expanded structure showing all atoms, including hydrogen, and all
bonds in for each of the following compounds
benzoic acid
acetone
10. (6 points) Write the semi-condensed structural formulas for each of the following compound (show
all important angles)
phenyl acetate
5-bromo-cis-2-methylhexene
11. (5 points) Draw semi-condensed structural formulas for all possible isomers of C3H8O.
12. (8 points) Write the complete, systematic name of each of the following compounds.
O
CH3
CH CH2
CH
CH2CH3
C
C
CH3
N
5
13. (4 points) CIRCLE ALL the asymmetric atoms in the compounds in the problem above.
CH3
C O C CH3
O
CH3
4
14. (8 points) Write complete structural formulas of the polymer produced from the following monomers.
In the blank, indicate whether the polymerization process is addition, condensation, or ring-opening.
CH3
O
CH3
type of polymerization:
NH2
HOOC
type of polymerization:
15. (12 points) Retrosynthesis is a planning process of working backwards from a desired target molecule
and determining which reactants can be used to make the molecule. This is usually a multistep
process and is used to design pathways to complex, bioactive molecules. In the cases below, you
need to use only one step. Show all of the starting molecules, and give any other reactants and
conditions (H+, heat ∆, etc.) needed to make the product shown on the right for FOUR of the following
five reactions. Write OMIT over the one you wish to skip or I will simply grade the first
four regardless of which ones are correct!
a.
O
O
O
O
O
O
CH3
b.
c.
Cl
CH3
CH3CH2
NH2+ClCH3
d.
CH2
O
CH3
H
e.
CH3
N
CH3
C
O
5
16. (21 points) Draw complete structural formulas for products of the reaction sequence shown below .
You may write either fully or partially condensed formulas as long as the molecular structure, including
the positions of functional group, is clearly shown. The full formula of the starting compound A is
C7H12O. [Note that it is often helpful to show all atoms, including H at the site of the reaction.]
H
C
O
[O]
A
"H2"
B
+ HBr
+ 2-propanol
E
H+ ∆
F
C
+ NaOH
- 2-propanol
G
+ HBr
D
+ NaOH
H (an isomer of F)
B