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CHM2045 F13: Final Exam
MULTIPLE CHOICE. Choose the one alternative that
best completes the statement or answers the question.
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1) Choose the statement below that is TRUE.
"A solution will form between two substances
if...
A) the solute-solute interactions are
stronger than the solute-solvent
interactions.
B) the solute-solvent, solute-solute, and
solvent-solvent interactions are of
comparable strength.
C) the solvent-solvent interactions are
stronger than the solute-solvent
interactions.
D) (A)-(C) are all true.
E) None of the above are true.
2013.12.09
4) A 0.334 g sample of an unknown halogen
occupies 109 mL at 398 K and 1.41 atm. What
is the identity of the halogen?
A) Ge
B) F 2
C) Cl2
D) Br2
E) I2
79
5) The Henry's law constant for helium gas in
water at 30°C is 3.70 × 10-4 M/atm. When the
partial pressure of helium above a sample of
water is 0.650 atm, the concentration of
helium in the water is ________ M.
A) 3.70 × 10-4
B) 1.30
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C) 1.76 × 10 3
D) 2.41 × 10 -4
2) Which of the following statements is TRUE?
A) The total number of molecular orbitals
formed doesn't always equal the
number of atomic orbitals in the set.
B) A bond order of 0 represents a stable
chemical bond.
C) When two atomic orbitals come
together to form two molecular
orbitals, one molecular orbital will be
lower in energy than the two separate
atomic orbitals and one molecular
orbital will be higher in energy than
the separate atomic orbitals.
D) Electrons placed in antibonding
orbitals stabilize the ion/molecule.
E) All of the above are true.
E) 5.69 × 10 -4
29 6) Choose the aqueous solution that has the
highest boiling point. These are all solutions
of nonvolatile solutes and you should assume
ideal van't Hoff factors where applicable.
A) 0.100 m LiBr
B) 0.100 m BaCl2
C) 0.100 m AlCl3
D) 0.100 m C6H12O6
E) They all have the same boiling point.
52 7) Which of the following statements is FALSE?
A) Molecules with hydrogen bonding are
more volatile than compounds with
dipole-dipole forces.
B) The rate of vaporization increases with
increasing temperature.
C) The rate of vaporization increases with
increasing surface area.
D) The rate of vaporization increases with
decreasing strength of intermolecular
forces.
E) None of the above are false.
82 3) Calculate the energy of the violet light
emitted by a hydrogen atom with a
wavelength of 410.1 nm.
A) 5.27 x 10-19 J
B) 8.13 × 10 -19 J
C) 4.85 × 10 -19 J
D) 2.06 × 10 -19 J
E) 1.23 × 10 -19 J
A-3
50
71 10) Determine the velocity of a sphere (m = 10.0
8) The boiling point elevation of an aqueous
sucrose solution is found to be 0.39°C. What
mass of sucrose (molar mass= 342.30 g/mol)
would be needed to dissolve in 500.0 g of
water? Kb (water) = 0.512°C/m.
kg) with a wavelength of 1.33 × 10 -35 m.
A) 2.21 m/s
B) 8.81 m/s
C) 4.98 m/s
D) 12.3 m/s
E) 6.44 m/s
A) 130. g sucrose
B) 528 g sucrose
C) 223 g sucrose
D) 762 g sucrose
E) 261 g sucrose
45
the number of core electrons for Cd.
74 11) Give
(Hint: It can only form +2 cations.)
A) 45
B) 46
C) 44
D) 48
E) 47
9) Use the molecular orbital diagram shown to
determine which of the following is most
stable.
81 12) Which of the following represent the Lewis
structure for Br⁻?
A)
B)
C)
D)
E)
15
13) Place the following substances in order of
decreasing vapor pressure at a given
temperature.
BeF 2
CH3OH
OF 2
A) CH3OH > OF2 > BeF 2
B) BeF 2 > CH3OH > OF2
C) OF 2 > BeF 2 > CH3OH
D) BeF 2 > OF 2 > CH3OH
E) OF 2 > CH3OH > BeF2
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A) B22⁺
14) Place the following in order of increasing
radius.
Br⁻
Na⁺
B) C22⁻
C) B2
A) Rb⁺ < Na⁺ < Br⁻
B) Br⁻ < Rb⁺ < Na⁺
C) Rb⁺ < Br⁻ < Na⁺
D) Br⁻ < Na⁺ < Rb⁺
E) Na⁺ < Rb⁺ < Br⁻
D) C22⁺
E) N22⁺
A-4
Rb⁺
52
64
85
69
76
53
26 21) How many of the following molecules are
15) Which reaction below represents the electron
affinity of Li?
A) Li(g) → Li⁺(g) + e⁻
B) Li⁺(g) → Li(g) + e⁻
C) Li⁺(g) + e⁻ → Li(g)
D) Li(g) + e⁻ → Li⁻(g)
E) Li(g) + e⁻ → Li⁺(g)
polar?
BrCl3
CS2
SiF4
SO3
A) 4
B) 3
C) 0
D) 1
E) 2
16) Determine the electron geometry (eg) and
molecular geometry (mg) of CH3+1.
A) eg=trigonal planar, mg=bent
B) eg=trigonal planar, mg=trigonal planar
C) eg=tetrahedral, mg=tetrahedral
D) eg=tetrahedral, mg=trigonal
pyramidal
E) eg=tetrahedral, mg=trigonal planar
72 22) Choose the best Lewis structure for SF 4.
A)
17) The distance between adjacent crests is called
A) wavelength
B) median
C) amplitude
D) area
E) frequency
B)
C)
18) Fluids used for an intravenous transfusion
are best if they are ________ with bodily
fluids.
A) hyposmotic
B) magnosmotic
C) isosmotic
D) neosmotic
E) hyperosmotic
19) When a wave encounters an obstacle or a slit
that is comparable in size to its wavelength, it
bends around it. This characteristic is called
________.
A) destructive interference
B) amplitude
C) diffraction
D) effusion
E) constructive interference
D)
E)
73
20) Identify the compound with the highest
percent ionic character.
A) LiF
B) HCl
C) IBr
D) HF
A-5
23) Halogens can react with each other to form
A) salts.
B) hydrogen halides.
C) metal halides.
D) ionic bonds.
E) covalent bonds.
86
72
73
73 28) Consider the phase diagram shown. Choose
24) Identify the number of electron groups
around a molecule with sp hybridization.
A) 1
B) 2
C) 5
D) 3
E) 4
the statement below that is TRUE.
25) At atmospheric pressure, dry ice ________.
A) melts
B) boils
C) deposits
D) freezes
E) sublimes
26) What is the strongest type of intermolecular
force present in NH2CH3?
A) dispersion
B) hydrogen bonding
C) ion-dipole
D) dipole-dipole
E) none of the above
67
A) The line separating the solid and liquid
phases represents the ∆Hvap .
B) The triple point of this substance
occurs at a temperature of 31°C.
C) At 10 atm of pressure, there is no
temperature where the liquid phase of
this substance would exist.
D) The solid phase of this substance is
higher in density than the liquid phase.
E) None of the above are true.
27) Choose the situation below that would result
in an endothermic ∆Hsolution.
A) When ∆Hsolute < ∆Hhydration
B) When ∆Hsolute > ∆Hhydration
C) When ∆Hsolvent >> ∆Hsolute
D) When ∆Hsolute is close to
∆Hhydration
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E) There isn't enough information to
determine.
29) A solution is prepared by dissolving 38.6 g
sucrose (C12H22O11) in 495 g of water.
Determine the mole fraction of sucrose if the
final volume of the solution is 508 mL.
A) 7.80 × 10 -2
B) 7.23 × 10 -2
C) 1.28 × 10 -3
D) 4.09 × 10 -3
E) 2.45 × 10 -3
87 30) Which of the following quantum numbers
describes the size and energy of an orbital?
A) principal quantum number
B) angular momentum quantum number
C) Schrödinger quantum number
D) spin quantum number
E) magnetic quantum number
A-6
89 36) Choose the valence orbital diagram that
the mass of water formed when
30 31) Determine
12.5 L NH (at 298 K and 1.50 atm) is reacted
represents the ground state of Zn.
A)
3
with 18.9 L of O 2 (at 323 K and 1.1 atm).
4 NH3(g) + 5 O 2(g) → 4
NO(g) + 6 H2O(g)
B)
A) 13.8 g H2O
B) 37.7 g H2O
C)
C) 27.9 g H2O
D) 20.7 g H2O
E) 17.0 g H2O
D)
83 32) The volume of a gas is proportional to
number of moles of a gas is known as
A) Dalton's Law
B) Boyle's Law
C) Avogadro's Law
D) Charles's Law
E) Ideal Gas Law
72
E)
56 37) Which of the following statements is TRUE?
A) In general, the solubility of a solid in
water decreases with increasing
temperature.
B) The solubility of a gas in water usually
increases with decreasing pressure.
C) The solubility of an ionic solid in water
decreases with increasing temperature.
D) In general, the solubility of a gas in
water decreases with increasing
temperature.
E) None of the above statements are true.
33) Determine the molality of an aqueous
solution prepared by dissolving 0.112 moles
of LiCl in 13.7 moles of H2O.
A) 0.122 m
B) 0.220 m
C) 0.454 m
D) 0.818 m
E) 0.153 m
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34) Which compound has the shortest
carbon-carbon bond length?
A) CH2CH2
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B) HCCH
C) CH3CH3
heat transfer system of internal combustion
engines in automobiles. Ethylene glycol is
nonvolatile. Give the reason that antifreeze is
added.
A) The freezing point and the boiling
point are lowered.
B) The freezing point is lowered and the
boiling point is elevated.
C) The freezing point and the boiling
point are elevated.
D) The freezing point is elevated and the
boiling point is lowered.
E) None of the above.
D) all bond lengths are the same
48
38) Antifreeze, an aqueous solution of ethylene
glycol (C2H6O2), is routinely added to the
35) Which of the following reactions is associated
with the lattice energy of RbI (∆H°latt)?
A) RbI(s) → Rb⁺(aq) + I⁻(aq)
B) Rb(s) + 1 I2(g) → RbI(s)
2
C) Rb⁺(g) + I⁻(g) → RbI(s)
D) RbI(s) → Rb⁺(g) + I⁻(g)
E) RbI(s) → Rb(s) + 1 I2(g)
2
A-7
69 39) Using the graph below, determine the gas
that has the highest density at STP.
A) B
B) D
C) C
D) A
E) All of the gases have the same density
at STP.
44 40) Which of the following statements is TRUE?
A) The larger a molecule, the faster it will
effuse.
B) Particles of different masses have the
same average speed at a given
temperature.
C) For a given gas, the lower the
temperature, the faster it will effuse.
D) At very high pressures, a gas will
occupy a larger volume than predicted
by the ideal gas law.
E) None of the above statements are true.
A-8
Answer Key
Testname: CHM2045 F13 PHINAL FINAL DRAFT
1) B
2) C
3) C
4) C
5) D
6) C
7) A
8) A
9) B
10) C
11) B
12) B
13) E
14) E
15) D
16) B
17) A
18) C
19) C
20) A
21) D
22) E
23) E
24) B
25) E
26) B
27) B
28) D
29) D
30) A
31) E
32) C
33) C
34) B
35) C
36) B
37) D
38) B
39) B
40) D
A-9