Chemistry 122
Final Exam
Winter 2009
March 16, 2009
Oregon State University
Dr. Richard Nafshun
Instructions: You should have with you several number two pencils, an eraser, your 3" x 5" note card, a
calculator, and your University ID Card. If you have notes with you, place them in a sealed backpack
and place the backpack OUT OF SIGHT or place the notes directly on the table at the front of the room.
Fill in the front page of the Scantron answer sheet with your last name, first name, middle initial, and
student identification number. Leave the class section number and the test form number blank.
This exam consists of 33 multiple-choice questions. Each question has four points associated with it
(Question 33 has two). Select the best multiple-choice answer by filling in the corresponding circle on
the rear page of the answer sheet. If you have any questions before the exam, please ask. If you have
any questions during the exam, please ask the proctor. Open and start this exam when instructed. When
finished, place your Scantron form in the appropriate stack and present your University ID Card to the
proctor. You may keep the exam packet, so please show your work and mark the answers you selected
on it.
R = 0.0821 L•atm/mol•K
M = mol/L
ΠV = nRT
A
ln[ ]   kt
Ao
SC: 2r = s
760 mm Hg = 760 torr = 1 atm
ΔTf = imkf
kf (H2O) = 1.86 ºC/m
 Ea
k  Ae RT
BCC: 4r = s√3
m = mol/kg
ΔTb = imkb
kb(H2O) = 0.512 ºC/m
Ka (CH3COOH) = 1.8 x 10-5
FCC: 4r = s√2
[Periodic Table of the Elements Here]
Please read each exam question carefully. Terms such as correct, false, unpaired, pairs, H-C-F bond angle, H-C-H
angle, greatest, and smallest are used.
Unit 1 Material (First assessed on Exam 1)
1.
There are ___ unpaired electrons in a ground-state nitride ion (N3-).
(A)
(B)
(C)
(D)
(E)
2.
Consider O2-, F-, Ne, Na+, and Na. Which is the smallest?
(A)
(B)
(C)
(D)
(E)
3.
15 core electrons and 5 valence electrons
5 core electrons and 15 valence electrons
10 core electrons and 5 valence electrons
5 core electrons and 10 valence electrons
15 core electrons and 15 valence electrons
The C-O-H bond angle in propanol, CH3CH2CH2OH, is:
(A)
(B)
(C)
(D)
(E)
5.
O2FNe
Na+
Na
How many core and valence electrons are present in a phosphorous atom?
(A)
(B)
(C)
(D)
(E)
4.
0
1
2
3
4
90
120
109.5
A little greater than 109.5
A little less than 109.5
Consider F, S, Ge, Sr, and O. The atom with the smallest atomic size is:
(A)
(B)
(C)
(D)
(E)
F
S
Ge
Sr
O
6.
The Lewis Dot Structure of ClF3 depicts:
(A)
(B)
(C)
(D)
(E)
7.
What is the oxygen-oxygen bond order in ozone (O3) and how many resonance forms can be
depicted?
(A)
(B)
(C)
(D)
(E)
8.
There are no lone pairs of electrons about the chlorine
There is one lone pair of electrons about the chlorine
There are two lone pairs of electrons about the chlorine
There are three lone pairs of electrons about the chlorine
There are four lone pairs of electrons about the chlorine
The oxygen-oxygen bond order is 2.00 and there are two resonance forms
The oxygen-oxygen bond order is 1.33 and there are two resonance forms
The oxygen-oxygen bond order is 1.33 and there are three resonance forms
The oxygen-oxygen bond order is 1.50 and there are two resonance forms
The oxygen-oxygen bond order is 1.50 and there are three resonance forms
Redraw the PCl2F3 molecule shown below as a Lewis Dot Structure depicting all electrons. The
F-P-F bond angle in this molecule is:
(A)
(B)
(C)
(D)
(E)
60º
90º
109.5º
120º
a little less than 109.5º
9.
The molecular geometry of CO2 is:
(A)
(B)
(C)
(D)
(E)
10.
The H-O-H bond angle in water a little less than 109.5. This deviation from the ideal bond
angle of 109.5 can be attributed to:
(A)
(B)
(C)
(D)
(E)
11.
lone pairs of electrons on oxygen
the high electronegativity of hydrogen
osmotic pressure
hydrogen bonding
milk
Consider MO (Molecular Orbital Theory). The F22- ion (a charge of minus two) is:
(A)
(B)
(C)
(D)
(E)
12.
bent
trigonal planar
trigonal pyramidal
linear
octahedral
paramagnetic
diamagnetic
übermagnetic
omgmagnetic
quasimagnetic
Consider MO (Molecular Orbital Theory). The N22- ion (a charge of minus two) has a bond
order of:
(A)
(B)
(C)
(D)
(E)
1.0
1.5
2.0
2.5
3.0
13.
Consider the molecule below and identify the correct statement.
(A)
(B)
(C)
(D)
(E)
There are 2 carbons that has an sp2 hybridization scheme and the molecule contains 3 π-bonds
There are 3 carbons that has an sp2 hybridization scheme and the molecule contains 4 π-bonds
There are 3 carbons that has an sp2 hybridization scheme and the molecule contains 3 π-bonds
There are 2 carbons that has an sp2 hybridization scheme and the molecule contains 4 π-bonds
There are 2 carbons that has an sp2 hybridization scheme and the molecule contains 2 π-bonds
Unit 2 Material (First assessed on Exam 2)
14.
The phase diagram below identifies 4 important points. Which point corresponds to the normal
boiling point of the substance at 1 atm?
D
C
A
B
15.
Sodium sulfide melts near 1176 ºC. Sodium chloride melts near 804 ºC. The difference in
melting points can be attributed to:
(A)
(B)
(C)
(D)
(E)
16.
Which of the following is false?
(A)
(B)
(C)
(D)
(E)
17.
Different intermolecular forces (dispersion, dipole-dipole, hydrogen bonding)
Different ionic charges (+1, +2, +3, -1, -2, -3…)
Different distances between nuclei (ionic size)
The sheet-like structure
Network covalent compounds
Carbon monoxide is a polar molecule which exhibits dispersion forces.
Oxygen dissolves in water due to dipole – induced dipole interactions.
Water is a polar molecule which exhibits hydrogen bonding.
The F2 molecule has a higher melting point than the Cl2 molecule as the F atom is
smaller.
Diamond and quartz are examples of network covalent compounds.
Consider CH3CH2OH, Na2O, CH3OH, Na2S, CH3OCH3 and Ne. Arranged in increasing melting
point, these are:
Lowest melting point
(A)
(B)
(C)
(D)
(E)
Highest melting point
CH3CH2OH < Ne < CH3OH < CH3OCH3
Ne < CH3OH < CH3OCH3 < CH3CH2OH
Ne < CH3OCH3 < CH3OH < CH3CH2OH
Ne < CH3OH < CH3OCH3 < CH3CH2OH
Ne < CH3OH < CH3CH2OH < CH3OCH3
<
<
<
<
<
Na2O
Na2O
Na2S
Na2S
Na2O
<
<
<
<
<
Na2S
Na2S
Na2O
Na2O
Na2S
18.
The Lewis Dot Structure for furan, C4H4O, is shown below. The intermolecular forces present in
furan are:
(A)
(B)
(C)
(D)
19.
Which of the following statements is false?
(A)
(B)
(C)
(D)
(E)
20.
Dispersion forces only
Dispersion forces and dipole-dipole forces
Dispersion forces, dipole-dipole forces, and hydrogen bonding
Dipole-dipole only
Polymers can form by condensation or addition of monomers
Monomers containing a triple bond can participate in addition polymerization
Nylon is a polymer that forms by a condensation reaction
Condensation polymerization always produces H2O as a product
Soaps possess both a hydrophilic (water loving) and a hydrophobic (water hating) end
The cubic form for the fictitious element Beaversium (Bs) is FCC. The atomic radius is 180.0
pm and the molar mass is 328.6 g/mol. The density of Bs is: [1 m = 1 x 1012 pm; 1 m = 100 cm]
(A)
(B)
(C)
(D)
(E)
59.0 g/cm3
30.8 g/cm3
23.4 g/cm3
5.85 g/cm3
16.5 g/cm3
21.
A student
dissolves 12.00 g of an unknown polymer in 800. mL of water at 323 K. She
measures the osmotic pressure to be 0.0671 mm Hg. What is the molar mass of the polymer?
(A)
(B)
(C)
(D)
(E)
22.
4.55 x 108 g/mol
5.96 x 106 g/mol
4.50 x 106 g/mol
2.25 x 106 g/mol
1.35 x 106 g/mol
A student (
) obtains a sample of 99mTc (t1/2 = 6.0058 hours). After exactly 20 hours the
student had only 6.00 milligrams remaining. What was the initial mass of the sample the student
received?
(A)
(B)
(C)
(D)
(E)
30.0 mg
0.115 mg
60.3 mg
10.0 mg
18.3 mg
23.
The following are initial rate data for:
(A)
(B)
(C)
(D)
(E)
24.
2A + B  2C
Experiment
Initial [A]
Initial [B]
Initial Rate
1
0.05
0.05
2.7
2
0.10
0.05
5.4
3
0.05
0.10
10.8
The rate law is Rate = k[A]1[B]2
The rate law is Rate = k[A]0[B]2
The rate law is Rate = k[A]2[B]0
The rate law is Rate = k[A]2[B]1
The rate law is Rate = k[A]1[B]1
A student requires a solution with a freezing point of -10.00 ˚C. What mass of ethylene glycol,
HOCH2CH2OH, would have to be added to 1.000 kg of water to obtain this freezing point?
(A)
(B)
(C)
(D)
(E)
121.1 g
19.53 g
333.4 g
5.377 g
0.08669 g
Unit 3 Material (Not previously assessed)
25.
26.
The equilibrium law expression for the reaction 2 NO2 (g)  O2 (g) + 2 NO (g) is:
(A)
Kc =
[O2 ][ NO]
[ NO2 ]2
(B)
Kc =
[O2 ] 2 [ NO]
[ NO2 ] 2
(C)
Kc =
[O2 ][ NO]2
[ NO2 ]2
(D)
Kc =
[O2 ][ NO]
[ NO2 ]
(E)
Kc =
[ NO 2 ]2
[ NO]2 [O 2 ]
A solution was made 3.3 x 10-5 M in [Cd2+] and 1.1 x 10-5 M in [OH-].
[Ksp of Cd(OH)2 = 7.2 x 10-15]
(A)
(B)
A solid will form
A solid will not form
27.
Consider the system
2 NO2 (g)
N2O4 (g)
Kc = 170
A student prepares the system and measures the following:
[N2O4] = 5.33  10-5 M
[NO2] = 5.60 × 10-4 M
(A)
(B)
28.
The system is at equilibrium.
The system is not at equilibrium.
The following reaction is at equilibrium:
2 SO3 (g)
(A)
(B)
(C)
29.
2 SO2 (g) + O2 (g)
The concentration of O2 (g) increases when SO2 is added
The concentration of O2 (g) decreases when SO2 is added
The concentration of O2 (g) stays the same when SO2 is added
The following reaction is at equilibrium:
2 SO3 (g)
(A)
(B)
(C)
2 SO2 (g) + O2 (g)
The concentration of O2 (g) increases when the system pressure is increased
The concentration of O2 (g) decreases when the system pressure is increased
The concentration of O2 (g) stays the same the system pressure is increased
30.
The pH of 0.040 M HNO3 (aq) is:
(A)
(B)
(C)
(D)
(E)
31.
4.00
0.400
0.040
1.40
0.912
The pH of 0.0250 M CH3COOH (aq) [K =1.8 x 10-5] is:
(A)
(B)
(C)
(D)
(E)
10.8
3.17
0.000671
-3.74
3.07
32.
A student obtains 0.105 M CH3COOH (aq). The “ICE” table used to solve the equilibrium
expression for this weak acid is:
+ H2O
(l)
I
C
E
CH3COOH
(aq)
0
+x
x
CH3COO(aq)
0.105
+x
0.105+x
+ H3O+
(aq)
0.105
+x
0.105+x
+ H2O
(l)
I
C
E
CH3COOH
(aq)
0.105
-x
0.105-x
CH3COO(aq)
0
+x/2
x/2
+ H3O+
(aq)
0
+x/2
x/2
+ H2O
(l)
I
C
E
CH3COOH
(aq)
0.105
-x
0.105-x
CH3COO(aq)
0
+x
x
+ H3O+
(aq)
0
+x
x
+ H2O
(l)
I
C
E
CH3COOH
(aq)
0.105
-x
0.105-x
CH3COO(aq)
0.105
+x
0.105+x
+ H3O+
(aq)
0.105
+x
0.105+x
+ H2O
(l)
I
C
E
CH3COOH
(aq)
0
-x
-x
CH3COO(aq)
0
+x/2
x
+ H3O+
(aq)
0
+x/2
x
(A)
(B)
(C)
(D)
(E)
33.
Well, well, well... CH 122 is over. Now it's time to:
(A)
(B)
(C)
(D)
(E)
Begin training for the 2014 Winter Olympic Games
Eat green beans
Herd zebras with helicopters (http://news.bbc.co.uk/2/hi/africa/8508737.stm)
Write a rap song about equilibrium—because so many words rhyme with “equilibrium”
American Idol and Pop Rocks
[Any response will receive full credit; even no response.]
Questions 1 through 32 have four points attached (128 total). Any response to Question 33 will receive full
credit (2 Points total); even no response. The point total for this exam is 130 points. See the grade sheet for
grade computation details. Final exam keys, scores, and course grades will be posted on the CH 122 website
as they become available.