You may write on this test, but only the Scantron Form will be scored!
Answer the questions on your Scantron form. Each question is worth 2 points.
Maximum Score: 40 points
MULTIPLE CHOICE. Choose the one alternative that best completes the
statement or answers the question.
1) Which of the following compound exhibits hydrogen bonding?
A)
B)
C)
D)
E)
CH3Cl
H2
H3C–O–CH3
NH3
None of the above
2) Which of the following compounds has the highest boiling point?
A)
B)
C)
D)
E)
CH3CH2OH
HOCH2CH2OH
H3C–O–CH3
CH3CH2CH2CH3
CH4
3) Which substance in each of the following pairs is expected to have the larger
dispersion forces?
I. Br2 or I2
II.
H H H H
H C C C C H
H H H H
n-butane
or
H
H C H
H
H
H C C C H
H H H
isobutane
A) Br2 in set I and n-butane in set II.
B) Br2 in set I and isobutane in set II
C) I2 in set I and n-butane in set II
D) I2 in set I and isobutane in set II
E) There is no difference in the dispersion forces.
4) What is the strongest type of intermolecular force present in H2?
A) ion-dipole
B) dispersion
C) dippole-dipole
D) hydrogen bonding
E) None of the above
5) What is the strongest type of intermolecular force present in CHF3?
A) hydrogen bonding
B) ion-dipole
C) dipole-dipole
D) dispersion
E) None of the above
6) Place the following compounds in order of increasing strength of intermolecular
forces. Start with the lowest strength.
SO2 F2 NH2CH3
A) SO2 < NH2CH3 < F2
B) F2 < SO2 < NH2CH3
C) F2 < NH2CH3 < SO2
D) NH2CH3 < F2 < SO2
E) NH2CH3 < SO2 < F2
7) What type of intermolecular force causes the dissolution of NaCl in water?
A) dispersion forces
B) hydrogen bonding
C) dipole-dipole forces
D) ion-dipole force
E) None of the above
8) Place the following substances in order of decreasing boiling point, starting with the
highest boiling point.
H2O N2
CO
A) N2 > CO > H2O
B) N2 > H2O > CO
C) H2O > CO > N2
D) CO > N2 > H2O
E) CO > H2O > N2
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9) Choose the substance with the highest viscosity.
A) (CH3CH2)2CO
B) C2H4Cl2
C) C6H14
D) HOCH2CH2CH2CH2OH
E) CF4
10) Which of the following statements is TRUE?
A) Intermolecular forces hold the atoms in molecules together.
B) Hydrogen bonds are chemical bonds.
C) Dispersion forces are generally stronger than dipole-dipole forces.
D) Vapor pressure increases with temperature.
E) None of the above are true.
11) Choose the substance with the lowest boiling point.
A) H2S
B) H2O2
C) CF2H2
D) NBr3
E) F2
12) Which of the following intermolecular forces is responsible for the formation of the
DNA double helix?
A)
B)
C)
D)
E)
Ion-Dipole
Dispersion Forces
Hydrogen Bonding
Dipole-Dipole
Covalent bonding
13) Which of the following statements is FALSE?
A)
B)
C)
D)
E)
Smaller atoms are more polarizable than larger atoms.
Boiling point increases as atomic radius increases
Dispersion forces are present in all molecules
Dipole-Dipole interactions exist only in polar molecules
Viscosity is defined as a liquid’s resistance to flow
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14) Which concept explains why the meniscus of mercury in a test tube is
concave-down?
A)
B)
C)
D)
E)
It has a high surface tension
It has more cohesive forces than adhesive forces
It has more adhesive forces than cohesive forces
It has more dipole-dipole interactions than dispersion forces
It is highly polarizable
15) The vapor pressure of ethanol at 34.7 °C is 100.0 mm Hg, and the heat of
vaporization of ethanol is 38.6 kJ/mol. What is the vapor pressure of ethanol (in mm
Hg) at 65.0 °C?
A)
B)
C)
D)
E)
1.21 mmHg
760 mmHg
386 mmHg
492 mmHg
None of the above are correct
16) Acetone is shown below. Which of the following statements lists ALL of the
intermolecular forces present in acetone?
H
C
H
A)
B)
C)
D)
E)
O
C
H
H
C H
H
Dipole-dipole, hydrogen bonding and dispersion forces
Dispersion forces and hydrogen bonding
Dispersion forces and ion-dipole forces
Dispersion forces and dipole-dipole forces
Dispersion forces, ion-dipole forces, and hydrogen bonding
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17) Which of the following molecules does NOT exhibit dipole-dipole forces?
A)
B)
C)
D)
E)
HCN
CF4
SeBr4
ICl3
More than one of the above compounds does not have dipole-dipole forces.
18) The following compounds have very similar molar masses:
H
O
C
H
F
H C H
H
Formaldehyde Fluoromethane
H O O H
Hydrogen Peroxide
H H
H C C H
H H
Ethane
F2
Fluorine
One of the above compounds is a liquid at room temperature while the rest are gases.
Which one is the liquid?
A)
B)
C)
D)
E)
Formaldehyde
Fluoromethane
Hydrogen Peroxide
Ethane
Fluorine
19) Water in a glass tube coated with grease or oil displays a flat meniscus, while water
in a clean glass tube displays a concave-up meniscus. Pick the statement that best
explains this difference.
A) Water experiences greater cohesive forces in the clean tube than in the greasy tube.
B) Water experiences greater adhesive forces in the greasy tube than in the clean tube.
C) Water experiences greater dispersion forces in the clean tube than in the greasy
tube.
D) Water experiences greater cohesive forces in the greasy tube than in the clean tube.
E) Water experiences more dispersion forces in the greasy tube than in the clean tube.
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20) From the plot of vapor pressure as a function of termperature shown below, the
normal boiling point for tert-butyl alcohol is approximately_____________.
A)
B)
C)
D)
E)
0 °C
22 °C
40 °C
85 °C
100 °C
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Reference Page
R = 8.314 J/ mol K
R = 0.08206 L atm/ mol K
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