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KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS
CHEMISTRY DEPARTMENT
CHEM-102-132-FINAL EXAM
000
TEST CODE NUMBER
STUDENT NUMBER:
NAME :
_____________________________
_____________________________
SECTION NUMBER:
_____________________________
INSTRUCTIONS
1.
2.
3.
4.
Write your student number, name, and section number on the EXAM COVER page.
Write your student number, section number, and your name on your EXAM ANSWER FORM.
Bubble in pencil your student number and your section number on the EXAM ANSWER FORM.
Bubble in pencil on your EXAM ANSWER FORM the correct answer to each of the questions.
You must not give more than ONE answer per question.
5. At the end of the exam return the EXAM ANSWER FORM to the proctor.
6. The exam contains 40 multiple choice questions and the time allowed is 160 min (2 hrs and 40
min). Time will be announced after 80 minutes and again 10 minutes before the end of the
exam.
Important constants
Gas Constant (R)
Planck’s Constant (h)
Velocity of light (c)
Avogadro’s number (N)
Bohr’s Constant (RH)
Faraday (F)
Specific heat of H2O
= 0.0821
= 8.314
= 8.31 x 107
= 6.626 x 10-34
= 6.626 x 10-34
= 2.998 x 108
= 6.022 x 1023
= 2.179 x 10-18
= 96485
= 4.18
L.atm/(mol.K)
J/(mol.K)
g.cm2/(sec2.mol.K)
J.sec/particle
kg.m2/(sec.particle)
m/sec
particles/mole
J/particle
Coulombs
J/(g.oC)
Name: __________________________ Date: _____________
Page 1
Page 2
1. For the reaction:
2A
+
B
+
2C
 D
+
E
the following initial rate data were collected at a constant temperature. Determine the
correct rate law for this reaction.
Trial #
1
2
3
4
A)
[A] (M)
0.225
0.320
0.225
0.225
[B] (M)
0.150
0.150
0.250
0.150
[C] (M) Rate(M/s)
0.350
0.0217
0.350
0.0439
0.350
0.0362
0.600
0.01270
 A   B
rate = k
 C
2
B) rate = k [A]2[B][C]
C) rate = k [A][B][C]
2
D)
A  B

rate = k
 C
2. For the reaction A  product, successive half-lives (i.e., first, second and third
half-lives) are observed to be 10, 20, 40 min
for an experiment in which [A]0 = 0.10
M.
Calculate the
concentration of A at t = 30 min.
A)
B)
C)
D)
0.025 M
0.1 M
8  10-3 M
0.08 M
Page 3
3. The mechanism for the reaction
2H2O
H2O2
+
2H+
+
2I –  I2
+
has been suggested as follows:
H2O2
+
I–
OH–
+
H+

HOI
+
OH–
slow
 H2O
fast
fast
HOI + H+ + I–  I2 +
H2O
Identify all intermediates included in the above mechanism.
A)
B)
C)
D)
HOI and OH–
H+ and HOI
H+ and H2O
H2O and OH–
4. At 500.0 K, one mole of gaseous ONCl is placed in a one-liter container. At equilibrium
9.0% of ONCl has dissociated according to the equation:
2ONCl(g)
2NO(g)
+
Cl2(g)
The equilibrium constant (Kc) for this reaction is:
A)
B)
C)
D)
4.4
2.2
1.1
2.2




10-4
102
102
10-4
5. The aqueous reaction:
L-glutamate + pyruvate
α-ketoglutarate + L-alanine
is catalyzed by a specific enzyme inside the human body. At 300 K, the equilibrium
constant for the reaction is 1.11  103. If concentrations of the reactants and products
are:
Species
Concentration
L-glutamate
3.0  10-5 M
pyruvate
3.3  10-4 M
α-ketoglutarate
L-alanine
-2
1.6  10 M 6.25  10-3 M
which of the following statements is correct?
A)
B)
C)
D)
The backward reaction will most probably occur.
The forward reaction will most probably occur.
No prediction can be made from the given data about this biological reaction.
The reaction is at equilibrium.
Page 4
6. Which of the following changes would cause a decrease in the value of Kc for the
reaction:
2NO(g) + O2 (g)
2 NO2 (g)
Ho = -113.10
kJ/mol
A)
B)
C)
D)
Increasing the temperature.
Adding a catalyst.
Increasing the volume of the reaction vessel.
Decreasing the volume of the reaction vessel.
7. Which oxide produces the most acidic solution when 0.1 mol is added to 1 L of H2O?
A)
B)
C)
D)
SO3
SO2
BaO2
BaO
8. What mass of sodium nitrite salt (NaNO2) must be added to 350.0 mL of water to give a
solution with pH = 8.40? [Ka(HNO2) = 5.6 × 10–4]
A)
B)
C)
D)
8.5 g
24 g
68 g
0.039 g
9. Arsenic acid, H3AsO4, is a polyprotic acid with K1 = 2.5 × 10–4, K2 = 5.6 × 10–8, and
K3 = 3 × 10–13. What is the approximate pH of a 0.500 M solution of arsenic acid?
A)
B)
C)
D)
1.96
4.51
0.85
3.90
10. The solubility product, Ksp for Al(OH)3 is 1.0×10-33. The concentration of aluminum
ion, [Al3+], in water at pH 6.5 is
A)
B)
C)
D)
3.2 × 10-11 M
1.3 × 10-13 M
7.5 × 10-12 M
7.9 × 10-15 M
Page 5
11. A 20.0 mL sample of 0.150 M ethylamine (CH3CH2NH2) is titrated with 0.0981 M HCl.
What is the pH after the addition of 5.0 mL of HCl? For ethylamine, pKb = 3.25.
A)
B)
C)
D)
11.46
2.96
11.04
10.75
12. Calculate the molar solubility of AgI in a 1.0 M NH3 solution. Given the following
equilibria:
AgI(s) ⇄ Ag(aq)  I(aq)
Ksp  8.3  1017
Ag(aq)  2NH3(aq) ⇄ Ag(NH3) 2 (aq)
Kf  1.5  107
A)
B)
C)
D)
3.5  105 M
6.1  1016 M
1.2  10 M
2.5  108 M
13. Calculate ΔSo for the following reaction at 25oC.
SiH4(g)
+
2O2(g)
→
SiO2(s)
+
2H2O(l)
Given the following data:
Species
Standard entropy, S0
(J/K•mol)
A)
B)
C)
D)
SiH4(g)
O2(g)
SiO2(s)
H2O(l)
204.5
205.0
41.84
69.91
- 432.8 J/K•mol
+595.0 J/K•mol
-880.3 J/K•mol
-353.5 J/K•mol
14. The sublimation of carbon dioxide at -78 oC is given by
CO2(s) 
CO2(g)
∆Hsub = 25.5 kJ/mol
Calculate the ∆Ssub when 84.4 g of CO2 sublimes at equilibrium at this temperature
A)
B)
C)
D)
251 J/K
139 J/K
622 J/K
390 J/K
Page 6
15. A chemical reaction is most likely to be spontaneous if it is accompanied by
A)
B)
C)
D)
lowering energy and increasing entropy.
increasing energy and decreasing entropy.
increasing energy and increasing entropy
lowering energy and decreasing entropy.
16. How many minutes would be required to electroplate (i.e., precipitate) 12.5 grams of
chromium (Cr) by passing a constant current of 4.80 amperes through a solution
containing CrCl3?
A)
B)
C)
D)
242 min
80.5 min
161 min
1.01 × 104 min
17. An electrochemical cell consists of a nickel metal electrode immersed in a solution with
[Ni2+] = 1.0 M connected through a salt bridge to an aluminum electrode immersed in a
solution with [Al3+] = 1.0 M. An amount of sodium hydroxide is added to the aluminum
solution half-cell, causing Al(OH)3 (s) to precipitate. After the precipitation of Al(OH)3
is over, the measured cell potential at 25oC is 1.82 V. What is the new concentration of
Al3+ in the solution?
A)
B)
C)
D)
Al3+(aq)
+
3e-
Al (s)
Ni2+(aq)
+
2e-
Ni (s)
E° = -1.66
E° = -0.23
1.7 × 1020 M
1.0 × 104 M
1.0 M
3.7 × 1012 M
18. Consider the following balanced redox reaction:
2+
2-
Mn (aq) + S2O8 (aq) + 2H2O(l)

Which of the following statements is true?
A)
B)
C)
D)
+
2-
MnO2(s) + 4H (aq) + 2SO4 (aq).
S2O82-(aq) is the oxidizing agent and is reduced.
H2O(l) is the reducing agent and is oxidized.
Mn2+(aq) is the reducing agent and is reduced.
2-
SO4 (aq) is the oxidizing agent and is reduced.
Page 7
19. Which statement about fusion is incorrect?
A)
B)
C)
D)
Nuclei required for fusion are not very much available on earth.
The nuclear reactions taking place in the sun are fusion reactions.
To fuse two nuclei, their speeds must be high enough to overcome their repulsion.
Fusion requires a very high temperature in order to begin.
20. Which of the following choices correctly represents the bombarding particle (x) and the
produced particle (y) in the nuclear reaction Fe(x,y)Co in which iron is transformed
to cobalt?
A)
B)
C)
D)
x = proton, y = neutron
x = -particle, y =  particle
x = electron, y = proton
x = neutron, y = positron
21. A volcanic rock contains a 206Pb/238U mass ratio of 0.372. If
a half-life of 4.51  109 yr, the approximate age of the rock is
A)
B)
C)
D)
2.33
4.51
1.05
6.42




109 yr
109 yr
109 yr
109 yr
22.
CH3
CH2CH2CH3
CH3CH2 C CH2 C H
OH H C CH3
CH3
The IUPAC name for the compound shown above is:
A)
B)
C)
D)
5-isopropyl-3-methyl-3-octanol
2,5-dimethyl-3-propyl-5-heptanol
2-ethyl-4-isopropyl-2-heptanol
6-methyl-4-isopropyl-6-octanol
Page 8
238
U decays to 206Pb with
23.
O
O
The two structures shown above represent:
A)
B)
C)
D)
structural isomers
enantiomers
resonance structures
stereoisomers
24. Identify the functional group circled in the following compound:
O
N
H
A)
B)
C)
D)
Amide.
Ketoamine
Secondary amine.
Lactone (cyclic ester).
25. A major pollutant that causes photochemical smog in cities is
A)
B)
C)
D)
nitrogen dioxide (NO2)
formaldehyde (H2CO)
carbon dioxide (CO2)
radon (Rn)
26. Which of the following gases make(s) rain acidic?
I. chlorofluorocarbons
II. methane gas
III. nitrogen oxides
A)
B)
C)
D)
III only
I and III
I, II and III
I only
Page 9
27. A “greenhouse gas” must
A)
B)
C)
D)
transmit visible sunlight and absorb infrared radiation.
be radioactive.
have no net change in dipole moment when it vibrates.
absorb both visible sunlight and infrared radiation.
28. What is the wavelength of a photon needed to dissociate an O3 molecule into O2 and O?
The bond energy in O3 is 107.2 kJ/mol.
A)
B)
C)
D)
1.12 × 103 nm
9.03 × 105 nm
5.22 × 10–4 nm
3.08 × 106 nm
29. The major cause of ozone depletion is associated with
A)
B)
C)
D)
the presence of chlorofluorocarbons serving as a source of atomic chlorine.
an increase in the green-house gases.
an increase in solar UV radiation.
the presence of oxides serving as sources of oxygen radicals.
30. What is the name of the compound [CoCl(NH3)5]Cl2?
A)
B)
C)
D)
pentaaminechlorocobalt(III) chloride.
pentaaminetrichlorocobalt(III).
chloropentaamincobalt(III) chloride.
pentaaminechlorocobaltate(III) chloride.
31. Which complex ion is most likely to be diamagnetic?
A)
B)
C)
D)
[Co(en)3]3+
[MnCl6]3[Cr(H2O)4Cl2]+
[Ni(H2O)6]2+
32. Use crystal field theory to determine the number of unpaired electrons in the complex
ion [Fe(CN)4(CO)2]2-.
A)
B)
C)
D)
0
2
3
4
Page 10
33. The correct formula for the coordination compound "sodium
dicyanobis(oxalato)ferrate(III)" is
A)
B)
C)
D)
Na3[Fe(CN)2(C2O4)2]
Na2[Fe(CN)2(C2O4)2]3Na2[Fe(CN)2(C2O4)2]2Na[Fe(CN)2(C2O4)2]
34. The coordination number of Ni in
A)
B)
C)
D)
K[Ni(en)(C2O4)(OH)2] is
6
8
4
5
35. Which statement is NOT correct about transition metals?
A)
B)
C)
D)
They have completely filled d orbitals.
They exhibit catalytic activity.
They form paramagnetic compounds.
Their first ionization energies increase as going from left to right for a given
period.
Page 11
36. The structure of methyl methacrylate monomer is given below
The structure of poly(methyl methacrylate) is:
A)
CH3
CH2 C
n
C O
O
CH3
B)
O
CH2
C C O CH2
CH2
n
C)
CH3 O
CH
C
C O CH2
n
D)
O
CH2 CH2 CH2 C O CH2
n
37. A semiconductor made mainly from silicon (Si) is doped with a small amount of
boron (B). This means that it is a/an:
A)
B)
C)
D)
p-type semiconductor, and will conduct electricity more efficiently.
n-type semiconductor, and will conduct electricity more efficiently.
p-type semiconductor, and will conduct electricity less efficiently.
n-type semiconductor, and will conduct electricity less efficiently.
38. Which of the following materials is not used to manufacture artificial joints for the
human body?
A)
B)
C)
D)
Fullerenes.
Polymeric materials such as polyethylene.
Titanium-based alloys.
Ceramics-based materials.
Page 12
39. Which compound is least likely to form a liquid crystal phase?
A)
B)
C)
D)
40. Which of the following structures represents a syndiotactic polymer?
A)
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
B)
C)
D)
NH
O
O
NH C
C
n
Page 13
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Answer Key
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31.
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35.
36.
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39.
40.
A
A
A
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A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
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