AP Chemistry
1st Semester Review
Practice Multiple Choice
Questions 1-4
(A) Heisenberg uncertainty principle
(B) Pauli exclusion principle
(C) Hund's rule (principle of maximum multiplicity)
(D) Shielding effect
(E) Wave nature of matter
1. Can be used to predict that a gaseous carbon atom in its
ground state is paramagnetic
2. Explains the experimental phenomenon of electron diffraction
3. Indicates that an atomic orbital can hold no more than two
electrons
4. Predicts that it is impossible to determine simultaneously the
exact position and the exact velocity of an electron
Questions 5-7 refer to the phase diagram below of a pure
substance.
(A) Sublimation
(D) Fusion
5.
(B) Condensation (C) Solvation
(E) Freezing
If the temperature increases from 10°C to 60°C at a constant
pressure of 0.4 atmosphere, which of the processes occurs?
6.
If the temperature decreases from 110°C to 40°C at a
constant pressure of 1.1 atmospheres, which of the
processes occurs?
7.
If the pressure increases from 0.5 to 1.5 atmospheres at a
constant temperature of 50°C, which of the processes
occurs?
Questions 8-10 refer to the following diatomic species.
(A) Li2
(B) B2
(C) N2
(D) O2
(E) F2
8.
Has the largest bond-dissociation energy
9.
Has a double bond
10. Contains 1 sigma () and 2 pi () bonds
11. In a molecule in which the central atom exhibits sp3d2 hybrid
orbitals, the electron pairs are directed toward the corners of
(A) a tetrahedron
(B) a square pyramid
(C) a trigonal bipyramid
(D) a square
(E) an octahedron
12. Commercial vinegar was titrated with NaOH solution to
determine the content of acetic acid, HC2H3O2. For 20. mL of
the vinegar, 32 mL of 0.50 M NaOH solution was required.
What was the concentration of acetic acid in the vinegar if no
other acid was present?
(A) 1.6 M
(B) 0.80 M
(C) 0.64 M
(D) 0.60 M
(E) 0.40 M
13. 2 H2O + 4 MnO4- + 3 CIO2-  4 MnO2 + 3 CIO4- + 4 OHWhich species acts as an oxidizing agent in the reaction?
(A) H2O (B) CIO4- (C) CIO2- (D) MnO2 (E) MnO414. _Ag+ + _AsH3(g) + _OH-  _Ag(s) + _H3AsO3(aq) + _H2O
When the equation above is balanced with lowest wholenumber coefficients, the coefficient for OH- is
(A) 2
(B) 4
(C) 5
(D) 6
(E) 7
15. Which statements about alpha particles are correct?
I. They have a mass number of 4 and a charge of +2.
II. They are more penetrating than beta particles.
III. They are helium nuclei.
(A) I only
(B) III only
(C) I and II only
(D) I and III only
(E) II and III only
16. A sample of 0.010 mole of oxygen gas is confined at 400 K
and 0.80 atm. What would be the pressure of this sample at
300 K and the same volume?
(A) 0.10 atm
(B) 0.20 atm
(C) 0.60 atm
(D) 0.80 atm
(E) 1.1 atm
17. Which actions would be likely to change the boiling point of a
sample of a pure liquid in an open container?
I. Placing it in a smaller container
II. Increasing the number of moles of the liquid in the
container
III. Moving the container and liquid to a higher altitude
(A) I only
(B) II only
(C) III only
(D) II and IIl only (E) I, II, and III
18. Given that a solution is 5 % sucrose by mass, what additional
information is necessary to calculate the molarity of the
solution?
I. The density of water
ll. The density of the solution
Ill. The molar mass of sucrose
(A) I only
(B) II only
(C) Ill only
(D) I and Ill only
(E) II and Ill only
19. When an aqueous solution of NaOH is added to an aqueous
solution of potassium dichromate, K2Cr2O7, the dichromate
ion is converted to
(A) CrO42(B) CrO2(C) Cr3+
(D) Cr2O3(s)
(E) Cr(OH)3(s)
20. CH3CH2OH boils at 78°C and CH3OCH3 boils at -24°C,
although both compounds have the same composition. This
difference in boiling points may be attributed to a difference in
(A) molecular mass
(B) density
(C) specific heat
(D) hydrogen bonding
(E) heat of combustion
21.
X: CH3-CH2-CH2-CH2-CH3
Y: CH3-CH2-CH2-CH2-OH
Z: HO-CH2-CH2-CH2-OH
Based on concepts of polarity and hydrogen bonding, which
sequence correctly lists the compounds above in the order of
their increasing solubility in water?
(A) Z < Y < X
(B) Y < Z < X
(C) Y < X < Z
(D) X < Z < Y
(E) X < Y < Z
1
22. A 3.0-g sample of an ideal gas at 127°C and 1.0 atm
pressure has a volume of 1.5 L. Which expression is correct
for the molar mass of the gas? R is 0.08 (L•atm)/(mole•K).
(A) (0.08)(400)/(3.0)(1.0)(1.5)
(B) (1.0)(1.5)/(3.0)(0.08)(400)
(C) (0.08)(1.0)(1.5)/(3.0)(400)
(D) (3.0)(0.08)(400)/(1.0)(1.5)
(E) (3.0)(0.08)(1.5)/(1.0)(400)
23. The system shown is at equilibrium at 28°(C) At this
temperature, the vapor pressure of water is 28 mm Hg.
30. All of the following statements concerning the characteristics
of the halogens are true EXCEPT:
(A) The first ionization energies (potentials) decrease as the
atomic numbers of the halogens increase.
(B) Fluorine is the best oxidizing agent.
(C) Fluorine atoms have the smallest radii.
(D) Iodine liberates free bromine from a solution of bromide
ion.
(E) Fluorine is the most electronegative of the halogens.
31. It is suggested that SO2 (MM = 64 g), which contributes to
acid rain, could be removed from a stream of waste gases by
bubbling the gases through 0.25 M KOH, thereby producing
K2SO3. What is the maximum mass in kg of SO2 that could
be removed by 1,000. L of the KOH solution?
(A) 4.0
(B) 8.0
(C) 16
(D) 20.
(E) 40.
The partial pressure of O2(g) in the system is
(A) 28 mm Hg
(B) 56 mm Hg
(C) 133 mm Hg
(D) 161 mm Hg
(E) 189 mm Hg
24. A strip of metallic scandium, Sc, is placed in a beaker
containing concentrated nitric acid. A brown gas forms, the
scandium disappears, and the resulting liquid is brown-yellow
but becomes colorless when warmed. These observations
best support which of the following statements?
(A) Nitric acid is a strong acid.
(B) In solution scandium nitrate is yellow and scandium
chloride is colorless.
(C) Nitric acid reacts with metals to form hydrogen.
(D) Scandium reacts with nitric acid to form a brown gas.
(E) One mole of Sc react for every three moles of nitric acid.
25.
Mass of an empty container
3.0 g
Mass of the container plus the solid
25.0 g
Volume of the solid sample
11.0 cm3
The data was gathered to determine the density of an
unknown solid. The density should be reported as
(A) 0.5 g/cm3
(B) 0.50 g/cm3
(C) 2.0 g/cm3
3
3
(D) 2.00 g/cm
(E) 2.27 g/cm
26. A sample of an ideal gas is cooled from 50.0oC to 25.0oC in a
sealed container of constant volume. Which values for the
gas will decrease?
I. The average molecular mass of the gas
II. The average distance between the molecules
III. The average speed of the molecules
(A) I only
(B) II only
(C) III only
(D) I and III
(E) II and III
27. Which has the lowest conductivity?
(A) 0.1 M CuSO4 (B) 0.1 M KOH
(D) 0.1 M HF
(E) 0.1 M HNO3
(C) 0.1 M BaCl2
28. What volume of 0.15 M HCI is required to neutralize 25 mL of
0.12 M Ba(OH)2?
(A) 20. mL
(B) 30. mL
(C) 40. mL
(D) 60. mL
(E) 80. mL
29. If 87 g of K2SO4 (MM = 174 g) is dissolved in enough water
to make 250 mL of solution, what are the concentrations of
the potassium and the sulfate ions?
(A)
(B)
(C)
(D)
(E)
[K+]
0.020 M 1.0 M 2.0 M 2.0 M 4.0 M
[SO42-] 0.020 M 2.0 M 1.0 M 2.0 M 2.0 M
32. Which of the molecules have a planar configuration?
I. BCl3
ll. CHCl3
Ill. NCl3
(A) I only
(B) Ill only
(C) I and II only
(D) II and Ill only (E) I, ll, and Ill
33. When 1.25 g of limestone was dissolved in acid, 0.44 g of
CO2 was generated. If the rock contained no carbonate
other than CaCO3, what was the percent of CaCO3 by mass
in the limestone?
(A) 35% (B) 44% (C) 67% (D) 80% (E) 100%
34. The electron-dot structure (Lewis structure) for which
molecule would have two unshared pairs of electrons on the
central atom?
(A) H2S
(B) NH3
(C) CH4
(D) HCN
(E) CO2
35. Which expression is correct for the maximum mass of
copper, in grams, that could be plated out by electrolyzing
aqueous CuCl2 for 16 hours at a constant current of 3.0 A?
(1 F = 96,500 C)
(A) (16)(3,600)(3.0)(63.55)(2)/(96,500)
(B) (16)(3,600)(3.0)(63.55)/(96,500)(2)
(C) (16)(3,600)(3.0)(63.55)/(96,500)
(D) (16)(60)(3.0)(96,500)(2)/(63.55)
(E) (16)(60)(3.0)(96,500)/(63.55)(2)
36. At 25°C, a sample of NH3 (MM = 17 g) effuses at the rate of
0.050 mole/minute. Under the same conditions, which gas
effuses at approximately one-half that rate?
(A) O2 (MM = 32 g)
(B) He (MM = 4.0 g)
(C) CO2 (MM = 44 g)
(D) Cl2 (MM = 71 g)
(E) CH4 (MM = 16 g)
37. Substances X and Y that were in a solution were separated
in the laboratory using the technique of fractional
crystallization. This fractional crystallization is possible
because substances X and Y have different
(A) boiling points
(B) melting points
(C) densities
(D) crystal colors
(E) solubilities
38. Which molecule has a dipole moment of zero (nonpolar
molecule)?
(A) CO2 (B) NO
(C) SO2 (D) NH3 (E) H2S
2
39. Which procedures for a titration are correct?
I. Draining a pipet by touching the tip to the side of the
container used for the titration
II. Rinsing the buret with distilled water just before
filling it with the liquid to be titrated
III. Swirling the solution frequently during the titration
(A) I only
(B) II only
(C) I and III only
(D) II and III only (E) I, II, and III
40.
_Fe(OH)2 + _O2 + _H2O  _Fe(OH)3
If 1 mole of O2 oxidizes Fe(OH)2 according to the reaction
represented above, how many moles of Fe(OH)3 can be
formed?
(A) 2
(B) 3
(C) 4
(D) 5
(E) 6
41. To determine the molar mass of a solid monoprotic acid, a
student titrated a weighed sample of the acid with standardized aqueous NaOH. Which could explain why the student
obtained a molar mass that was too large?
I. Failure to rinse all acid from the weighing paper into
the titration vessel
II. Addition of more water than was needed to dissolve
the acid
III. Addition of some base beyond the equivalence point
(A) I only
(B) III only
(C) I and II only
(D) II and III only (E) I, II, and III
42. A direct-current power supply of low voltage (less than 10 V)
has lost the markings that indicate which output terminal is
positive and which is negative. A chemist suggests that the
power supply terminals be connected to a pair of platinum
electrodes that dip into 0.1 M KI solution. Which would
correctly identifies the polarities of the power supply
terminals?
(A) A gas will be evolved only at the positive electrode.
(B) A gas will be evolved only at the negative electrode.
(C) A brown color will appear in the solution near the
negative electrode.
(D) A metal will be deposited on the positive electrode.
(E) None of the methods above will identify the polarities of
the power supply terminals.
Questions 43-44 refer to the following types of energy.
(A) Activation energy
(B) Free energy
(C) Ionization energy
(D) Kinetic energy
(E) Lattice energy
43. The energy required to convert a ground-state atom in the
gas phase to a gaseous positive ion
44. The energy change that occurs in the conversion of an ionic
solid to widely separated gaseous ions
Questions 45-48 refer to atoms for which the occupied atomic
orbitals are shown below.
(A) 1s( ) 2s( )
(B) 1s() 2s()
(C) 1s() 2s()2p()()()
(D) 1s() 2s()2p()()()
(E) [Ar] 4s() 3d()()()()()
45. Represents an atom that is chemically unreactive
46. Represents an atom in an excited state
47. Represents an atom that has four valence electrons
Questions 49-52 refer to the following descriptions of bonding in
different types of solids.
(A) Lattice of positive and negative ions held together by
electrostatic forces
(B) Closely packed lattice with delocalized electrons
throughout
(C) Strong single covalent bonds with weak intermolecular
forces
(D) Strong multiple covalent bonds (including 1 bonds) with
weak intermolecular forces
(E) Macromolecules held together with strong polar bonds
49. Cesium chloride, CsCI(s)
50. Gold, Au(s)
51. Carbon dioxide, CO2(s)
52. Methane, CH4(s)
Questions 53-54 refer to the following elements.
(A) Lithium
(B) Nickel
(C) Bromine
(D) Uranium
(E) Fluorine
53. Is a gas in its standard state at 298 K
54. What mass in grams of Au is produced when 0.0500 mol of
Au2S3 is reduced completely with excess H2?
(A) 9.85 (B) 19.7 (C) 24.5 (D) 39.4 (E) 48.9
55. Which best explains why a hot-air balloon rises?
(A) The pressure on the walls of the balloon increases with
increasing temperature.
(B) The difference in temperature between the air inside and
outside the balloon produces convection currents.
(C) The cooler air outside the balloon pushes in on the walls
of the balloon.
(D) The rate of diffusion of cooler air is less than that of
warmer air.
(E) The air density inside the balloon is less than that of the
surrounding air.
56. _C10H12O4S(s) + _O2(g)  _CO2(g) + _SO2(g) + _H2O(g)
When the equation above is balanced and all coefficients are
reduced to their lowest whole-number terms, the coefficient
for O2(g) is
(A) 6
(B) 7
(C) 12
(D) 14
(E) 28
57. The melting point of MgO is higher than that of NaF.
Explanations for this observation include which of the
following?
I. Mg2+ is more positively charged than Na+.
II. O2- is more negatively charged than F-.
III. The O2- ion is smaller than the F- ion.
(A) II only
(B) I and II only
(C) I and III only
(D) II and III only (E) I, II, and III
58. H2Se(g) + 4 O2F2(g)  SeF6(g) + 2 HF(g) + 4 O2(g)
Which is true regarding the reaction represented above?
(A) Oxidation number of O does not change.
(B) Oxidation number of H changes from -1 to + 1.
(C) Oxidation number of F changes from + 1 to -1.
(D) Oxidation number of Se changes from -2 to +6.
(E) It is a disproportionation reaction for F.
59. If the temperature of an aqueous solution of NaCI is
increased from 20°C to 90°C, which statement is true?
(A) The density of the solution remains unchanged.
(B) The molarity of the solution remains unchanged.
(C) The molality of the solution remains unchanged.
(D) The mole fraction of solute decreases.
(E) The mole fraction of solute increases.
48. Represents an atom of a transition metal
3
60. Types of hybridization exhibited by the C atoms in propene,
CH3CHCH2 include
I. sp
II. sp2
III. sp3
(A) I only
(B) III only
(C) I and II only
(D) II and III only (E) I, II, and III
61. A 1.0 L sample of an aqueous solution contains 0.10 mol of
NaCI and 0.10 mol of CaCl2. What is the minimum number
of moles of AgNO3 that must be added to the solution in
order to precipitate all of the CI- as AgCI(s)? (Assume that
AgCI is insoluble.)
(A) 0.10 mol
(B) 0.20 mol
(C) 0.30 mol
(D) 0.40 mol
(E) 0.60 mol
Questions 62-63 refer to an electrolytic cell that involves the halfreaction: AIF63- + 3 e-  Al + 6 F-.
62. Which occurs in the reaction?
(A) AIF63- is reduced at the cathode.
(B) Al is oxidized at the anode.
(C) Aluminum is converted from the -3 oxidation state to the
0 oxidation state.
(D) F- acts as a reducing agent.
(E) F- is reduced at the cathode.
63. A steady current of 10 amperes is passed through an
aluminum-production cell for 15 minutes. Which is the
correct expression for calculating the number of grams of
aluminum produced? (1 F = 96,500 C)
(A) (10)(15)(96,500)/(27)(60) g
(B) (10)(15)(27)/(60)(96,500) g
(C) (10)(15)(60)(27)/(96,500)(3) g
(D) (96,500)(27)/(10)(15)(60)(3) g
(E) (27)(3)/(96,500)(10)(15)(60) g
64. The ionization energies for element X are listed in the table.
Ionization Energies for element X (kJ/mol)
First
Second
Third
Fourth
Fifth
580
1,815
2,740
11,600
14,800
On the basis of the data, element X is most likely to be
(A) Na
(B) Mg
(C) Al
(D) Si
(E) P
65. Which molecule has the largest dipole moment?
(A) CO
(B) CO2 (C) O2
(D) HF
(E) F2
66. A rigid metal tank contains oxygen gas. Which applies to the
gas in the tank when additional oxygen is added at constant
temperature?
(A) the volume of the gas increases.
(B) The pressure of the gas decreases.
(C) The average speed of the molecules remains the same.
(D) The total number of molecules remains the same.
(E) The average distance between the molecules increases.
67. The phase diagram for a pure substance is shown.
Which point corresponds to the equilibrium between the solid
and liquid phases at the normal melting point?
(A) A
(B) B
(C) C
(D) D
(E) E
68. _Li3N(s) + _H2O(I)  _Li+(aq) + _OH-(aq) + _NH3(g)
When the equation above is balanced and all coefficients
reduced to lowest terms, the coefficient for OH-(aq) is
(A) 1
(B) 2
(C) 3
(D) 4
(E) 6
69. When hafnium metal is heated in an atmosphere of chlorine
gas, the product of the reaction is found to contain 62.2
percent Hf by mass and 37.4 percent Cl by mass. What is
the empirical formula for this compound?
(A) HfCI (B) HfCl2 (C) HfCl3 (D) HfCl4 (E) Hf2Cl3
70. If 87.5 percent of a sample of pure 131I decays in 24 days,
what is the half-life of 131I in days?
(A) 6
(B) 8
(C) 12
(D) 14
(E) 21
71. Which technique is most appropriate for the recovery of solid
KNO3 from an aqueous solution of KNO3?
(A) Paper chromatography
(B) Filtration
(C) Titration
(D) Electrolysis
(E) Evaporation to dryness
72. In the periodic table, as the atomic number increases from 11
to 17, what happens to the atomic radius?
(A) It remains constant.
(B) It increases only.
(C) It increases, then decreases.
(D) It decreases only.
(E) It decreases, then increases.
73. Which is a correct interpretation of the results of Rutherford's
experiments in which gold atoms were bombarded with alpha
particles?
(A) Atoms have equal numbers of positive and negative
charges.
(B) Electrons in atoms are arranged in shells.
(C) Neutrons are at the center of an atom.
(D) Neutrons and protons in atoms have nearly equal mass.
(E) The positive charge of an atom is concentrated in a
small region.
74. Under which set of conditions could the most O2(g) be
dissolved in H2O(I)?
Pressure of O2(g)
Temperature
Above H2O(I)
of H2O(I)
(atm)
(oC)
(A)
5.0
80
(B)
5.0
20
(C)
1.0
80
(D)
1.0
20
(E)
0.5
20
75. 10 HI + 2 KMnO4 + 3 H2SO4  5 I2 + 2 MnSO4 + K2SO4 + 8 H2O
According to the balanced equation above, how many moles
of HI would be necessary to produce 2.5 mol of I2, starting
with 4.0 mol of KMnO4 and 3.0 mol of H2SO4?
(A) 20.
(B) 10.
(C) 8.0
(D) 5.0
(E) 2.5
76. A yellow precipitate forms when 1 M NaI(aq) is added to a 1
M solution of which ion?
(A) Pb2+ (B) Zn2+ (C) CrO42- (D) SO42- (E) OH-
4
77. M(s) + 3 Ag+(aq)  3 Ag(s) + M3+(aq)
Eo = + 2.46 V
Ag+(aq) + e-  Ag(s)
Eo = + 0.80 V
According to the information above, what is the standard
reduction potential for the half-reaction
M3+(aq) + 3 e-  M(s)?
(A) –1.66 V
(B) –0.06 V
(C) 0.06 V
(D) 1.66 V
(E) 3.26 V
85. When 100 mL of 1.0 M Na3PO4 is mixed with 100 mL of 1.0
M AgNO3, a yellow precipitate forms and [Ag+] becomes
negligibly small. Which is a correct listing of the ions
remaining in solution in order of increasing concentration?
(A) [PO43-] < [NO3-] < [Na+] (B) [PO43-] < [Na+] < [NO3-]
(C) [NO3-] < [PO43-] < [Na+] (D) [Na+] < [NO3-] < [PO43-]
(E) [Na+] < [PO43-] < [NO3-]
78. On a mountaintop, it is observed that water boils at 90°C, not
at 100°C as at sea level. This occurs because on the
mountaintop the
(A) equilibrium water vapor pressure is higher due to the
higher atmospheric pressure
(B) equilibrium water vapor pressure is lower due to the
higher atmospheric pressure
(C) equilibrium water vapor pressure equals the atmospheric
pressure at a lower temperature
(D) water molecules have a higher average kinetic energy
due to the lower atmospheric pressure
(E) water contains a greater concentration of dissolved
gases
86. In a qualitative analysis for the presence of Pb2+, Fe2+, and
Cu2+ ions in aqueous solution, adding which diluted solution
will allow the separation of Pb2+ from the other ions at room
temperature?
(A) Na2S (B) HCI (C) NaOH (D) NH3 (E) HNO3
79. A 40. mL sample of 0.25 M KOH is added to 60. mL of 0.15
M Ba(OH)2. What is the molar concentration of OH-(aq) in
the resulting solution? (Assume volumes are additive.)
(A) 0.10 M
(B) 0.19 M
(C) 0.28 M
(D) 0.40 M
(E) 0.55 M
80. NH4NO3(s)  N2O(g) + 2 H2O(g)
A 0.03 mol sample of NH4NO3(s) is placed in 1 L evacuated
flask, which is then sealed and heated. The NH4NO3(s)
decomposes completely according to the balanced equation
above. The total pressure in the flask measured at 400 K is
closest to (R = 0.08 L•atm/mol•K)
(A) 3 atm
(B) 1 atm
(C) 0.5 atm
(D) 0.1 atm
(E) 0.03 atm
81. Equal numbers of moles of He(g), Ar(g), and Ne(g) are
placed in a glass vessel at room temperature. If the vessel
has a pinhole-sized leak, which will be true regarding the
relative values of the partial pressures of the gases
remaining in the vessel after some of the gas mixture has
effused?
(A) PHe < PNe < PAr
(B) PHe < PAr < PNe
(C) PNe < PAr < PHe
(D) PAr < PHe < PNe
(E) PHe = PAr = PNe
82. In which process are covalent bonds broken?
(A) I2(s)  I2(g)
(B) CO2(s)  CO2(g)
(C) NaCl(s)  NaCl(l)
(D) C(diamond)  C(g)
(E) Fe(s)  Fe(l)
Questions 87-88 Consider atoms of the following elements.
Assume that the atoms are in the ground state.
(A) S
(B) Ca
(C) Ga
(D) Sb
(E) Br
87. The atom that contains exactly two unpaired electrons
88. The atom that contains only one electron in the highest
occupied energy sublevel
Questions 89-91 refer to the following molecules.
(A) CO2 (B) H2O (C) CH4 (D) C2H4 (E) PH3
89. The molecule with only one double bond
90. The molecule with the largest dipole moment
91. The molecule that has trigonal pyramidal geometry
Questions 92-94 refer to the following gases at 0°C and 1 atm.
(A) Ne
(B) Xe
(C) O2
(D) CO
(E) NO
92. Has an average atomic or molecular speed closest to that of
N2 molecules at 0°C and 1 atm
93. Has the greatest density
94. Has the greatest rate of effusion through a pinhole
Questions 95-97 refer to the reactions represented below.
(A) H2SeO4(aq) + 2 CI- + 2 H+  H2SeO3(aq) + Cl2(g) + H2O(l)
(B) S8(s) + 8 O2(g)  8 SO2(g)
(C) 3 Br2(aq) + 6 OH-  5 Br- + BrO3- + 3 H2O(l)
(D) Ca2+ + SO42-  CaSO4(s)
(E) PtCI4(s) + 2 CI-  PtCI6295. A precipitation reaction
96. A reaction in which the same reactant undergoes both
oxidation and reduction
97. A combustion reaction
Questions 98-99 The graph shows the temperature of a pure
substance as it is heated at a constant rate in an open vessel
at 1.0 atm pressure. The substance changes from the solid to
the liquid to the gas phase.
83. What is the final concentration of barium ions, [Ba2+], in
solution when 100. mL of 0.10 M BaCI2(aq) is mixed with
100. mL of 0.050 M H2SO4(aq)?
(A) 0.00 M
(B) 0.012 M
(C) 0.025 M
(D) 0.075 M
(E) 0.10 M
84. Which gas deviates most from ideal behavior?
(A) SO2 (B) Ne
(C) CH4 (D) N2
(E) H2
98. The substance is at its normal freezing point at time
(A) t1
(B) t2
(C) t3
(D) t4
(E) t5
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99. Which best describes what happens to the substance
between t4 and t5?
(A) The molecules are leaving the liquid phase.
(B) The solid and liquid phases coexist in equilibrium.
(C) The vapor pressure of the substance is decreasing.
(D) The average intermolecular distance is decreasing.
(E) The temperature of the substance is increasing.
100. In which group are the three species isoelectronic; i.e., have
the same number of electrons?
(A) S2-, K+, Ca2+
(B) Sc, Ti, V2+
(C) O2-, S2-, CI(D) Mg2+, Ca2+, Sr2+
(E) Cs, Ba2+, La3+
107.
CS2(l) + 3 O2(g)  CO2(g) + 2 SO2(g)
What volume of O2(g) is required to react with excess CS2(l)
to produce 4.0 L of CO2(g)? (Assume all gases are measured
at 0°C and 1 atm.)
(A) 12 L
(B) 22.4 L
(C) ⅓ x 22.4 L
(D) 2 x 22.4 L
(E) 3 x 22.4 L
108. On the basis of the solubility curves shown below, the
greatest percentage of which compound can be recovered by
cooling a saturated solution of that compound from 90°C to
30°C?
101. The phase diagram for the pure substance X is shown.
The temperature is raised from 10°C to 100°C at a constant
pressure of 0.5 atm. What is the expected behavior?
(A) It first melts to a liquid and then boils at about 70°C.
(B) It first melts to a liquid and then boils at about 30°C.
(C) It melts to a liquid at about 20°C and remains a liquid
until the temperature is greater than 100°C.
(D) It sublimes to vapor at about 20°C.
(E) It remains a solid until the temperature is greater than
100°(C)
102. A flask, contains 0.25 mole of SO2(g), 0.50 mole of CH4(g),
and 0.50 mole of O2(g). The total pressure of the gases in
the flask is 800 mm Hg. What is the partial pressure of the
SO2(g) in the flask?
(A) 800 mm Hg
(B) 600 mm Hg
(C) 250 mm Hg
(D) 200 mm Hg
(E) 160 mm Hg
103. A compound contains 1.10 mol of K, 0.55 mol of Te, and 1.65
mol of O. What is the simplest formula of this compound?
(A) KTeO
(B) KTe2O
(C) K2TeO3
(D) K2TeO6
(E) K4TeO6
104. Approximately what mass of CuSO4• 5 H2O (MM = 250 g) is
required to prepare 250 mL of 0.10 M copper(II) sulfate
solution?
(A) 4.0 g (B) 6.2 g (C) 34 g (D) 85 g (E) 140 g
105. Of the following compounds, which is the most ionic?
(A) SiCl4 (B) BrCl (C) PCl3 (D) Cl2O (E) CaCl2
106. The best explanation for the fact that diamond is extremely
hard is that diamond crystals
(A) are made up of atoms that are intrinsically hard because
of their electronic structures
(B) consist of positive and negative ions that are strongly
attracted to each other
(C) are giant molecules in which each atom forms strong
covalent bonds with all of its neighboring atoms
(D) are formed under extreme conditions of temperature and
pressure
(E) contain orbitals or bands of delocalized electrons that
belong not to single atoms but to each crystal as a whole
(A) NaCI
(D) K2SO4
(B) KNO3
(E) Ce2(SO4)3
(C) K2CrO4
109. The atomic mass of copper is 63.55. Given that there are
only two naturally occurring isotopes of copper, 63Cu and
65Cu, the natural abundance of the 65Cu isotope must be
approximately
(A) 90% (B) 70% (C) 50% (D) 25% (E) 10%
110. Which property generally decreases across the periodic table
from sodium to chlorine?
(A) First ionization energy
(B) Atomic mass
(C) Electronegativity
(D) Maximum value of oxidation number
(E) Atomic radius
111. The effective nuclear charge experienced by the outermost
electron of Na is different than the effective nuclear charge
experienced by the outermost electron of Ne. Which best
accounts for this difference?
(A) Na has a greater density at standard conditions than Ne.
(B) Na has a lower first ionization energy than Ne.
(C) Na has a higher melting point than Ne.
(D) Na has a higher neutron-to-proton ratio than Ne.
(E) Na has fewer naturally occurring isotopes than Ne.
112. Sodium chloride is LEAST soluble in which liquid?
(A) H2O
(B) CCl4
(C) HF
(D) CH3OH
(E) CH3COOH
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113. 3 Cu(s) + 8 H+ + 2 NO3-  3 Cu2+ + 2 NO(g) + 4 H2O
Which are true statements about the reaction above?
I. Cu(s) acts as an oxidizing agent.
II. The oxidation state of nitrogen changes from +5 to
+2.
III. Hydrogen ions are oxidized to form H2O.
(A) I only
(B) II only
(C) III only
(D) I and II
(E) II and III
114. Propane gas, C3H8, burns in excess oxygen gas. When the
equation for this reaction is correctly balanced and all
coefficients are reduced to their lowest whole-number terms,
the coefficient for O2 is
(A) 4
(B) 5
(C) 7
(D) 10
(E) 22
115. According to the VSEPR model, the progressive decrease in
the bond angles in the series of molecules CH4, NH3, and
H2O is best accounted for by the
(A) increasing strength of the bonds
(B) decreasing size of the central atom
(C) increasing electronegativity of the central atom
(D) increasing number of unshared pairs of electrons
(E) decreasing repulsion between hydrogen atoms
116. The boiling points of the elements helium, neon, argon,
krypton, and xenon increase in that order. Which statement
accounts for this increase?
(A) The London (dispersion) forces increase,
(B) The hydrogen bonding increases.
(C) The dipole-dipole forces increase.
(D) The chemical reactivity increases.
(E) The number of nearest neighbors increases.
117. 2 H2O + 4 MnO4- + 3 CIO2-  4 MnO2(s) + 3 CIO4- + 4 OHAccording to the balanced equation above, how many moles
of CIO2- are needed to react completely with 20. mL of 0.20
M KMnO4 solution?
(A) 0.0030 mol
(B) 0.0053 mol
(C) 0.0075 mol
(D) 0.013 mol
(E) 0.030 mol
118. Which describes the changes in forces of attraction that
occur as H2O changes phase from a liquid to a vapor?
(A) H–O bonds break as H–H and O–O bonds form.
(B) Hydrogen bonds between H2O molecules are broken.
(C) Covalent bonds between H2O molecules are broken.
(D) Ionic bonds between H+ ions and OH- ions are broken.
(E) Covalent bonds between H+ ions and H2O molecules
become more effective.
119. Of the following pure substances, which has the highest
melting point?
(A) S8
(B) I2
(C) SiO2 (D) SO2 (E) C6H6
120. In the electroplating of nickel, 0.200 faraday of electrical
charge is passed through a solution of NiSO4. What mass of
nickel is deposited?
(A) 2.94 g
(B) 5.87 g
(C) 11.7 g
(D) 58.7 g
(E) 294 g
121. Heat energy is added slowly to a pure solid covalent
compound at its melting point. About half of the solid melts
to become a liquid. Which of the following must be true
about this process?
(A) Covalent bonds are broken as the solid melts.
(B) The temperature of the solid/liquid mixture remains the
same while heat is being added.
(C) The intermolecular forces present among molecules
become zero as the solid melts.
(D) The volume of the compound increases as the solid
melts to become a liquid.
(E) The average kinetic energy of the molecules become
greater as the molecules leave the solid state and enter
the liquid state.
Questions 122-123 refer to the figures below. The figures show
portions of a buret used in a titration of an acid solution of known
concentration with a saturated solution of Ba(OH)2. Figures I and
2 show the level of the Ba(OH)2 solution at the start and at the
endpoint of the titration, respectively. Phenolphthalein was used
as the indicator for the titration.
Figure 1
Figure 2
122. What is the evidence that the endpoint of the titration has
been reached?
(A) The color of the solution in the buret changes from pink
to colorless.
(B) The color of the solution in the buret changes from blue
to red.
(C) The color of the contents of the flask changes from
colorless to pink.
(D) The color of the contents of the flask changes from blue
to red
(E) The contents of the flask change from clear to cloudy.
123. The volume of saturated Ba(OH)2, used to neutralize the acid
was closest to
(A) 6.60 mL
(B) 22.80 mL
(C) 23.02 mL
(D) 23.20 mL
(E) 29.80 mL
124. In which of the following are the chemical species correctly
ordered from smallest radius to largest radius?
(A) B < C < N
(B) At < Xe < Kr
(C) CI < S < S2(D) Na < Na+ < K (E) K+ < Ca2+ < K
125. Of the following elements, which would be expected to have
chemical properties most similar to those of sulfur, S?
(A) Br
(B) CI
(C) N
(D) P
(E) Se
126. When a solution is formed by adding some methanol,
CH3OH, to water, processes that are endothermic include
which of the following?
I. Methanol molecules move water molecules apart as
the methanol goes into solution.
II. Water molecules move methanol molecules apart
as the methanol goes into solution.
III. Intermolecular attractions form between molecules
of water and methanol as the methanol goes into
solution.
(A) I only
(B) III only
(C) I and II only
(D) II and III only (E) I, II and III
127. Of the following gases, which has the greatest average
molecular speed at 298 K?
(A) Cl2
(B) NO
(C) H2S (D) HCN (E) PH3
128. Types of hybridization exhibited by carbon atoms in a molecule
of propyne, CH3CCH, include which of the following?
I. sp
II. sp2
III. sp3
(A) I only
(B) III only
(C) I and III only
(D) II and III only (E) I, II and III
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