Download Chemistry 116: General Chemistry

Chemistry 116: General Chemistry
Syracuse University Project Advance
Final Exam, Spring 2009
Name
Date
1. Which of the following does not affect the rate of a chemical reaction?
A.
B.
C.
D.
E.
Physical state of the reactants
Presence of a catalyst
Concentration of the reactants
Shape of the container
Temperature
2. Chlorine atoms photochemically derived from Freons help destroy stratospheric ozone in the
two-step mechanism below. We classify the respective species Cl and ClO for the overall
balanced reaction as
Cl + O2  ClO + O2
ClO + O  Cl + O2
A.
B.
C.
D.
E.
both Catalysts
both intermediates
catalyst and intermediate
intermediate and catalyst
both activated complexes
3. Which of the following 0.1M solutions would have a pH of 7.0 at 25oC?
A.
B.
C.
D.
E.
NaOCl
KCl
NH4Cl
Ca(C2H3O2)2
None of these would have a pH of 7.0
4. What is the pH of a solution that is 0.010 M in acetic acid (Ka(HC2H3O2) = 1.8  10-5) and
0.010 M in sodium acetate?
A.
B.
C.
D.
E.
2.74
3.74
4.74
5.74
6.74
5. Which of the following combinations is suitable for making a buffer?
1. HCl and NaCl
2. HF and NaF
3. HCl and NaOH
A.
B.
C.
D.
E.
1 only
2 only
3 only
1 and 2 only
2 and 3 only
6. Which of the following statements referring to the following reaction is correct?
N2(g) + 3Cl2(g)  2NCl3(g)
A.
B.
C.
D.
E.
The N2 acts as the oxidizing angent and the Cl2 as a reducing agent
The Cl2 acts as an oxidizing agent and the N2 as a reducing agent
Both N2 and Cl2 are oxidizing agents.
Both N2 and Cl2 are reducing agents.
No oxidation or reduction occurs in this reaction
7. A closed system of three gases is governed by the reversible reaction shown. Kp = 4  10-7 at
the current temperature of the mixture, PNO2 = 4.1  10-2 atm, PNO = 8.9  10-4 atm, and PO2 =
8.5  10-3 atm. In order to reach equilibrium, how must the system adjust?
2 NO2(g)
2 NO(g) + O2(g)
A. The system is already at equilibrium.
B. More NO2 must be formed from NO and O2.
C. More NO and O2 must be formed from NO2.
8. Which of the following is not a allotrope of carbon?
A.
B.
C.
D.
E.
methane
carbon nanotubes
diamond
buckminsterfullerene
graphite
9. Calculate G˚ for the following reaction at 500 K.
A.
B.
C.
D.
E.
Cu(s) + H2O(g)
CuO(s) + H2(g)
Cu(s)
H2O(g)
CuO(s)
H2(g)
H˚f (kJ/mol)
0
-241.8
-155.2
0
S˚ (J/mol-K)
33.3
188.7
43.5
130.6
-86.6 kJ
-62.6 kJ
+23.9 kJ
+110.6 kJ
+301 kJ
10. A typical cup of black coffee has a hydroxide concentration of 1.17  10-9. Based on this,
A.
B.
C.
D.
E.
coffee is basic since the pH is 8.9
coffee is neutral since the pH is very close to 9.
coffee is acidic since the pH is 8.9.
coffee is basic since the pH is 5.1.
coffee is acidic since the pH is 5.1.
11. The equilibrium constant for a certain reaction is 5.0  108 at 25˚C. What is the value of G
for this reaction?
A.
B.
C.
D.
E.
-50 kJ/mol
-25 kJ/mol
-22 kJ/mol
-4.2 kJ/mol
22 kJ/mol
12. Which process would be expected to have S very close to zero?
A.
B.
C.
D.
E.
N2(g) + O2(g)  2 NO(g)
H2O(s)  H2O(l)
H2O(g)  H2O(s)
OF2(g) + H2O(g)  O2(g) + 2 HF(g)
2H2(g) + O2(g)  2H2O(g)
13. What is the IUPAC name for this compound?
CH2CH2CH3

CH3CHCHCH2CH3

CH3
A.
B.
C.
D.
E.
2-methyl-3-propylhexane
3-ethyl-2-methylhexane
4-methyl-3-propylpentane
4-ethyl-5-propylhexane
1,1-dimethyl-2-propylbutane
14. Ksp for Pb3(PO4)2 is 10-44. Two solutions are mixed, one containing Pb2+ and the other PO43-.
If, at the instant of mixing, [Pb2+] = 10-6 M and [PO43-] = 10-8 M, which statement is true?
A.
B.
C.
D.
E.
A precipitate forms because Qsp > Ksp.
A precipitate forms because Qsp < Ksp.
No precipitate forms because Qsp = Ksp.
No precipitate forms because Qsp > Ksp.
No precipitate forms because Qsp < Ksp.
15. Methylmercury, a toxic compound that can occur in contaminated fish, is eliminated from the
human body in a first-order process with a half-life of 70 days. After a fish-eating contest,
the champion had a blood concentration of methylmercury of 0.200 mg/L. What would be
the expected blood concentration after 350 days?
A.
B.
C.
D.
E.
0.006 mg/L
0.010 mg/L
0.050 mg/L
0.065 mg/L
0.195 mg/L
16. Which of the following indicates that a reaction is first order?
A.
B.
C.
D.
E.
The reaction is faster at higher temperatures.
The reaction has only one type of reactant.
The rate remains constant when the reactant concentration is doubled.
The reaction slows down as time goes on.
The half life remains constant as time goes on.
17. Given the following standard reduction potentials, which species is the strongest oxidizing
agent?
Cr3+(aq) + e-  Cr2+(aq)
Ni2+(aq) + e-  Ni(s)
A.
B.
C.
D.
E.
E˚ = -0.41 V
E˚ = -0.28 V
Cr3+(aq)
Cr2+(aq)
Ni2+(aq)
Ni(s)
None of these are oxidizing agents.
18. Which statement is true about the following reaction? (Ka(HC2H3O2) = 1.8  10-5, Ka(H2S) =
8.9  10-8)
H2S(aq) + C2H3O2-(aq)
A.
B.
C.
D.
E.
HS-(aq) + HC2H3O2(aq)
The equilibrium lies to the right, toward the stronger acid.
The equilibrium lies to the right, toward the weaker acid.
The equilibrium lies to the left, toward the stronger acid.
The equilibrium lies to the left, toward the weaker acid.
None of the above is correct.
19. When a 1 liter flask initially containing 0.5 mole of I2 and 0.5 mole of Br2 comes to
equilibrium, the flask is found to contain 0.84 mole of IBr. What is the value of Kc for this
reaction?
I2(g) + Br2(g)   2IBr(g)
A.
B.
C.
D.
E.
11
4.0
110
601
None of these
20. What is the product "X" from this reaction?
235
92





A. 141
54 Xe
143
B. 54 Xe
C. 140
55 Cs
141
D. 56 Ba
E. 143
56 Ba
1
U  X 92
36 Kr 2 0 n
21. Which of the following would likely be a successful method for the production of hydrogen,
H2?
A.
B.
C.
D.
E.
Treatment of a metal with acid
Treatment of water with a base
High-temperature combustion of alkanes
Treatment of baking soda with vinegar
High-temperature pyrolysis of silica (sand)
22. What is the molar solubility of AgI in pure water? Ksp(AgI) = 8.51  10-17.
A.
B.
C.
D.
E.
4.26  10-17 M
8.51  10-17 M
9.22  10-9 M
2.77  10-6 M
4.40  10-5 M
23. Why is N2 generally resistant to react?
A.
B.
C.
D.
E.
There are not many possible N-containing compounds that could be products.
N2 has an especially strong bond between the N atoms.
As a gas molecule, N2 does not often collide with other reactants.
The lone pairs on N do react but only reversibly.
Reactions with N2 are indeed thermodynamically favorable, but they are just slow.
24. Which compound can occur as cis-trans isomers?
A.
B.
C.
D.
E.
25.
CH3CH=CH2
CH3CH=C(CH3)2
CH3CH=CHCH2CH3
(CH3)2CHCH2CH3
CH3CH(Cl)CH2CH3
Which functional group is most likely found to be in a polyester suit?
A.
B.
C.
D.
E.
-COOH
–COO–CO–NH2none of the above
26. Using the initial rate data in the table for the reaction shown, determine the rate law.
X + Y  Z
X (M)
0.10
0.20
0.30
0.15
0.20
A.
B.
C.
D.
E.
Y (M)
0.10
0.40
0.80
0.80
0.20
Initial rate (M/s)
2.3 × 10–5
7.4 × 10–4
4.4 × 10–3
2.2 × 10–3
1.8 × 10–4
rate = k[X]
rate = k[X][Y]
rate = k[X][2Y]
rate = k[X]2[Y]
rate = k[X][Y]2
27. What is the coefficient of the permanganate ion when the following equation is correctly
balanced?
MnO4- + I- ------> Mn2+ + I2
A.
B.
C.
D.
E.
ACIDIC SOLUTION
1
2
3
5
None of these
28. At a given temperature, Kc = 0.020 for the equilibrium
PCl5(g)
PCl3(g) + Cl2(g)
What is Kc for
2 Cl2(g) + 2 PCl3(g)
A.
B.
C.
D.
E.
0.020
50
100
500
2500
2 PCl5(g)
29. The best criterion for the spontaneity of a chemical reaction is the sign of
A.
B.
C.
D.
E.
H°
H
G°
G
TS
30. How many hydrogen atoms are needed to complete the following structure?
C
C
C
C
C
A.
B.
C.
D.
E.
6
8
10
12
14
31. What is the correct name for
CH3CHCH2CH=CH2
|
CH3
A. 2-methyl-4-hexane
B. 2-methyl-4-pentene
C. 2-methyl-cis-4-pentene
D. 4-methyl-2-hexene
E. 4-methyl-1-pentene
32. The decomposition of di-t-butyl peroxide is a first-order reaction.
C8H18O2(g)  C3H6O(g) + C2H6(g)
di-t-butyl peroxide
acetone
ethane
The half-life at 135˚C is 320 minutes, and the half-life at 145˚C is 100 minutes. What is the
activation energy (Ea)?
A.
B.
C.
D.
E.
165 kJ/mol
181 kJ/mol
203 kJ/mol
211 kJ/mol
244 kJ/mol
33. Why are nuclear transmutations that are induced by neutron impact easier to accomplish than
those induced by impact of protons or alpha particles?
A. Protons and alpha particles, being positively charged, are shielded from the nucleus by
electrons.
B. Protons and alpha particles are more massive than neutrons and therefore harder to
accelerate.
C. Protons and alpha particles have smaller cross-sections than neutrons and are therefore
less likely to collide with the nucleus.
D. Protons and alpha particles, being positively charged, are repelled by the nucleus.
E. Protons and alpha particles are more massive than neutrons and therefore more likely to
cause undesired reactions upon impact with the nucleus.
34. Alpha-decay produces a new nucleus whose
original nucleus.
A)
B)
C)
D)
E)
than those respectively of the
atomic number is 2 less and mass number is 2 less
atomic number is 1 less and mass number is 2 less
atomic number is 2 less and mass number is 4 less
atomic number is 2 more and mass number is 4 more
atomic number is 2 more and mass number is 2 less
35. The respective standard reduction potentials in V for Zn2+ and Fe2+ are –0.76 and –0.44,
respectively. Determine the value of E°cell for a voltaic cell in which the overall reaction is
Zn + Fe2+ ------> Fe + Zn2+
A)
B)
C)
D)
E)
0.32 V
–0.32 V
1.20 V
–1.20 V
–0.76 V
Final Exam Key
SUPA CHEM Spring 2009
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A