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Transcript
Multiple Choice Practice.
A)
31
15
P
B) 3126 S
C) 3157 Cl
D)
7
3
Li
E)
19
9
F
1. Has the lowest first ionization energy
2. Has only three electrons in the 3 p energy level
3. Has a higher ionization energy than the element on either side of it in the same period of the
periodic table
4. Of the above, has the smallest atomic radius.
A) C2F4
B) HCN
C) CO2
D) BaCl2
E) Br2
5. Contains a nonpolar covalent single bond.
6. Contains two double bonds
7. Contains a triple bond
8. Is a polar molecule that contains polar bonds
9. Contains only one π bond.
A) Na+
B) NH4+
C) Fe3+
D) S2–
E) I–
10. Is the strongest Lewis acid
11. Hydrolyzes extensively with water to give a basic solution
12. Is a Brønsted acid
13. Is LEAST reactive with common laboratory reageants.
A) A solution with a pH less than 7 that is not a buffer solution.
B) A buffer solution with a pH between 4 and 7
C) A buffer solution with a pH between 7 and 10
D) A solution with a pH greater than 7 that is not a buffer solution
E) A solution with a pH of 7.
(Ionization constants...CH3COOH = 1.8 x 10–5 NH3=1.8x10–5
H2CO3: K1 = 4 x 10–7 ; K2 = 4 x 10–11 )
14. A solution prepared to be initially 1 M in NaCl and 1 M in HCl
15. A solution prepared to be initially 1 M in Na2CO3 and 1 M in CH3COONa
16. A solution prepared to be initially 0.5 M in CH3COOH and 1 M in CH3COONa
17. The weight of H2SO4 (MW = 98.1) in 50.0 mL of a 6.00-molar solution is
A) 3.10 grams B) 13.0 grams C) 29.4 grams D) 294 grams E) 300 grams
18. Which of the following samples contains 2.0 x 1023 atoms?
A) 35 grams Cl2 B) 8.0 grams O2 C) 4.0 grams C D) 2.0 grams He E) 1.0 gram H2
19. An oxidation state that is common to Fe, Mn, and Zn is
A) +1 B) +2 C) +3 D) +4 E) +5
Changes in State Properties of Systems
ΔH
A) +
B) 0
C) 0
D) –
E) –
20.
21.
22.
23.
ΔS
ΔG
–
0
+
–
+
0
0
–
–
–
Water freezes at –10 C and 1 atmosphere
An ideal gas expands into a vacuum at constant temperature
Water and ice at 0 C and 1 atmosphere are in dynamic equilibrium
Ozone decomposes exothermically into oxygen gas ( 2 O3(g)  3 O2(g) )
Pb2+ + 2 e– = Pb E = –0.126 V
Ag+ + e– = Ag
E = 0.799 V
A galvanic cell is made by a combination of the half-cells listed above.
24. The standard potential of this galvanic cell is
A) 0.673 volt B) 0.925 volt C) 1.05 volts D) 1.34 volts
D) 1.85 volts
25. When all of the species are in the standard state, the reaction at the cathode in this galvanic
cell is A) Ag Ag+ + e–
B) Ag+ + e–  Ag C) Pb  Pb2+ + 2 e–
2+
–
D) Pb + 2 e  Pb
E) Pb2+ + Ag + e–  Pb + Ag
26. In a titration of a weak acid of unknown concentration with a standard solution of a strong
base, a pH meter was used to follow the progress of the titration. Which of the following is
true for this experiment? A) The pH is 7 at the equivalence point
B) The pH at the equivalence point depends on the indicator used
C) The graph of pH vs. volume of base added rises gradually at first, and then much more
rapidly D) The graph of pH vs. volume of base added shows no sharp rise.
E) The [H+] at the equivalence point equals the ionization constant of the acid.
27. A sample of an ideal gas weighs 10. grams and has a volume of 1.5 liters at a temperature
of 27C and a pressure of 2.0 atmospheres. What is its molecular weight?
A) 7.4 B) 41 C) 82 D) 126
E) 164
28. All of the following are true for most ionic solids EXCEPT
A) They are crystals in which ions occupy the lattice points B) They have a tendency to
fracture by cleavage C) They have fairly high melting points D) They are good
conductors of electricity in the molten state E) They are held together primarily by van der
Waals forces.
29. ...IO3– + ...H+ + ... e–
 I2
+ H2O
When the half reaction above is balanced, how many moles of electrons are needed for every
mole of I2 formed by this half-reaction? A) 2 B) 6 C) 8 D) 10 E) 12
30. Which of the following is always true at the triple point of a pure substance?
A) The vapor pressure of the solid phase equals the vapor pressure of the liquid phase
B) The temperature is 0.01K lower than the normal melting point
C) The liquid and gas phases have the same density and are therefore indistinguishable
D) The solid phase melts if the pressure increases at constant temperature
E) The liquid phase vaporizes if the pressure increases at constant temperature
31. Which of the following compounds is most ionic?
A) SiCl4 B) BrCl C) PCl3 D) Cl2O E) CaCl2
32. The simplest formula for an oxide of nitrogen that is 36.8 percent nitrogen by mass is
A) N2O B) NO C) NO2
D) N2O3
E) N2O5
33. Compounds of which of the following functional groups are noted for their pleasant odors
and flavors? A) alcohol B) amine C) organic acid D) ether E) ester
34. Which of the following is probably true for a solid solute with a highly endothermic heat of
solution when dissolved in water? A) The solid has a low lattice energy
B) As the solid dissolved, the temperature of the substance increases
C) The resulting solution is ideal D) The solid is more soluble at higher temperatures
E) The solid has a high energy of hydration
35. A compound having the empirical formula C7H6S has a molecular weight of 365 ±4. The
molecular formula for this compound is A) C7H6S B) C14H12S2
C) C14H18S3
D) C21H12S3
E) C21H18S3
36. At 25C, solutions with a pH of 8 have a hydroxide ion concentration, [OH– ] of
A) 10–14 molar B) 10–8 molar C) 10–6 molar D) 1 molar E) 8 molar
37. The Pauli exclusion principle states that A) the velocity of all electromagnetic radiation
equals the speed of light B) all particles with mass also have a wave length
C) the velocity of an electron and its exact position cannot be known at the same instant
D) each electron in an atom has its own unique set of four quantum numbers
E) as many electrons as possible remain unpaired within one atomic subshell
38. A 0.1 molar solution of which of the following is colorless?
C) Na2CrO4 D) KMnO4 E) CuSO4
A) MgCl2
39. In which of the following is hydrogen bonding most significant?
A) HBr B) H2S C) CH3CF3 D) LiH E) CH3OH
B) Ni(NO3)2
N2O4(g)
 2 NO2(g)
40. The temperature of an equilibrium mixture of the substances in the equation above is
increased while the volume of the system is held constant. The standard enthalpy change,
ΔH for this reaction is greater than zero. Which of the following also remains constant?
A) the equilibrium constant B) the pressure C) the concentration of NO2
D) the mass E) the moles of N2O4
41. The units in which rate constants are expressed are A) dependent on the rate equation
B) mole liter–1
C) liter2mole–2sec–2 D) sec–1 E) liter mole–1 sec–1
42.
...K(s) + ....KNO3(s)
 ...K2O(s)
+ ...N2(g)
When the equation above is balanced, it indicates that the number of moles of solid potassium
needed in order to produce one mole of N2 is A) 1 mole B) 2 moles C) 3 moles
D) 6 moles E) 10 moles
43.
S(s) + 3 F2(g)
 SF6(g)
For the reaction above at standard temperature and pressure, the volume of F2 required to
produce 0.500 mole of SF6 is A) 67.2 liters B) 33.6 liters C) 22.4 liters D) 11.2 liters
E) 1.5 liters
44. Which of the following must be true about a certain reaction for which the enthalpy change,
ΔH, is –12 kilojoules?
I. The enthalpy of the products is lower than the enthalpy of the reactants
II. The reaction is exothermic
III. The reaction occurs spontaneously.
A) I only B) II only C) I and II
D) I and III
E) II and III
45. Which of the following molecules has the largest dipole moment?
A) CO2 B) CF4 C) CCl4 D) H2S E) H2O
46. The non volatile compound ethylene glycol, C2H6O2 , forms nearly ideal solutions with
water. What is the vapor pressure of a solution made from 1.00 mole of C2H6O2 and 9.00
moles of water if the vapor pressure of pure water at that temperature is 25 millimeters of Hg?
A) 2.50 mm B) 7.50 mm C) 12.5 mm D) 22.5 mm E) 27.5 mm
47. A reaction produced a colorless gas, which was collected by water displacement. A glowing
splint inserted into a bottle full of the gas was extinguished. The gas could have been
A) N2 B) NO2 C) O2 D) Br2 E) Cl2
48. Thomson’s cathode ray experiments supported the hypothesis that
A) atoms contain electrons B) practically all of the mass of an atom is contained in its
nucleus. C) atoms contain protons, neutrons, and electrons D) atoms have a positively
charged nucleus surrounded by anb electron cloud E) no two electrons in one atom can have
the same four quantum numbers.
CH3
H


CH3–C–CH2–C–CH2–CH3

H

CH3
49. Which of the following is a correct name for the compound above?
A) 2-methyl 4-ethylheptane B) 2,4-dimethyhexane C) 2,4-dimethyl heptane
D) 2-methyl, 4-ethylbutane E) 2,4-dimethyloctane
50. A salt sample is being analyzed to determine the % by mass of sulfate. All of the following
are appropriate steps in a procedure to perform this determination EXCEPT
A) determining the mass of the sample to be used for analysis
B) adding excess barium chloride solution to a solution of the sample
C) collecting on filter paper the barium sulfate formed
D) measuring the volume of water from which the barium sulfate precipitate is removed
E) determining the mass of he barium sulfate formed.
51. If the density of a certain compound in the gas phase is 1.89 grams per liter, and the density
of oxygen gas at the same temperature and pressure is 1.04 grams per liter, then the
approximate molecular mass of the compound is A) 17.6 B) 29.1 C) 35.2
D) 58.2 E) 182
52. The freezing point of paradichlorobenzene is 53.1C; its molal freezing point constant is
7.10 C/m . A solution containing 66.7 grams of solute per kilogram of paradichlorobenzene
freezes at 50.2C. What is the approximate molecular weight of the solute?
A) 370 B) 160 C) 62 D) 28 E) 27
53. Which of the following is the strongest acid?
D) HOClO E) HOClO
54.
A) Mg(OH)2
B) NaH
C) C2H5OH
4 X (s) + 3 O2(g)  X4O6
Element X reacts with oxygen gas in the manner indicated above. Of the following, element
X is most likely to be A) Ca B) K C) Cl D) P E) S
55. The SbCl5 molecule has a trigonal bipyramid structure. The hybridization of the Sb orbitals
is A) sp2 B) sp3 C) dsp2 D) dsp3 E) d2sp3
EXPERIMENT
INITIAL [A]
INITIAL [B]
INITIAL RATE OF
FORMATION OF C
(M/MIN)
1
0.20 M
0.20 M
4.0x10–3
2
0.20 M
0.40 M
8.0 x 10–3
3
0.40 M
0.20 M
1.6 x 10–2
4
0.40 M
0.40 M
3.2 x 10–2
The reaction rate experiements shown above refer to the following reaction:
2 A + 2 B  C + D.
56. Which of the following is the rate law for this reaction?
A) Rate = k[A][B]
B) Rate = k[A]2[B]
C) Rate = k[A][B]2
E) Rate = k[A]2
H H H
  
57. Which of the following is an isomer of H—C—C—C—I
  
H H H
?
D) Rate = k[A]2[B]2
A)
H H H
  
H—C—C—C—H
  
I H H
D)
B)
H H H
  
H—C—C—C—H
  
H I H
H H H H
   
H—C—C—C—C—H
   
H H H I
E)
C) H H H
  
H—C—C—C—H
  
H H I
H H H H
   
H—C—C—C—C—I
   
H H H H
58.
...Fe3+ + ...H2S(aq)
 ...S(s)
+ ...FeS(s) + ... H+
When the equation above is balanced, it shows that S and FeS are formed in the mole ratio
S:FeS of A) 1:1 B) 1:2 C) 1:3
D) 2:3
E) 3:2
59. When 12510Sb emits a positron, the product nucleus is A) 119Sn B) 120Sn C) 121Sn
D) 120Te E) 121 Te. (The atomic number of Sn is 50; that of Te is 52)
60. For the oxides of the elements of the third period, the general trend of acidity from left to
right progresses from A) acidic, to amphoteric, to basic B) basic, to amphoteric, to acidic
C) amphoteric, to basic, to acidic
D) amphoteric, to acidic, to basic
E) basic, to acidic,
to amphoteric.
61 For solutions of H2S in water, the values of the Ka’s, K1 and K2, are 1.0 x 10–7 and
1.3 x 10–13 respectively. Which of the following statements concerning 0.1 molar solutions
of Na2S and NaHS is correct?
A) both solutions are neutral B) the Na2S solution is more basic C) the concentration of
H2S is greater in the Na2S solution D) both solutions are acidic E) both solutions have
the same pH.
62. If 500 mL of Hydrogen gas and 1500 mL of carbon dioxide gas each at 760 millimeters of
Hg pressure and 25C are mixed without reacting and the final pressure of the mixture is 760
mm of Hg, what is the partial pressure of the CO2 gas? A) 760 mm B) 570 mm
C) 380 mm D) 251 mm E) 190 mm
63. CCl4, CO2, PCl3 , PCl5, SF6.
Which of the following does not describe any of the
listed molecules? A) linear B) octahedral C) square planar D) tetrahedral
E) trigonal pyramid
64. If a mixture of x moles of C2H6 plus y moles of C4H10 is burned in excess oxygen, what
number of moles of CO2 is produced? A) x + y B) x + 2y C) 2x + y
D) 2x + 2 y E) 2x + 4 y
65. Factors that affect the rates of many heterogeneous chemical reactions include which of the
following?
I. Changes in the partial pressures of any gaseous reactants.
II. Changes in the particle sizes of any solid reactants
III. The amount of stirring.
A) III only B) I and II only C) I and III only D) II and III only E) I, II, and III
66. C(s) + O2(g)  CO2(g)
2C (s) + O2(g) 2 CO(g)
ΔH = – 393.5 kJ
ΔH = –221.1 kJ
The heats of combustion of graphite to CO2 and CO are given above. What is the standard
enthalpy change for the reaction CO(g) + ½ O2  CO2(g) ?
A) –283.0 kJ
B) –627.1 kJ
C) –172.4 kJ
D) + 172.4 kJ
E) + 627. 1 kJ
67. CH3CSNH2 + H2O  CH3CONH2 + H2S. The rate equation for this reaction in
dilute acid solution is found to be rate = k[H3O+][CH3CSNH2]
All of the following statements about the reaction are true EXCEPT
A) Adding H2O increases the reaction rate B) Increasing the temperature increases the
reaction rate C) The mechanism of this reaction cannot be described by the stoichiometry
D) The addition of water leaves the value of the rate constant unchanged. E) Adding 1
milliliter of concentrated HCl increases the rate more than adding 1 milliliter of concentrated
acetic acid.
68. In the titration of a 1-molar solution of HNO2 ( Ka = 4.5 x 10–4 ) with a strong base, an
indicator should be used that changes color A) between pH 1 and pH 4
B) at pH 4 C) between pH 4 and pH 7 D) at pH 7 E) above pH 7
69. A solution is prepared by dissolving 7.30 grams of HCl (MW = 36.5 ) in 100. grams of
water. From this information it can be determined that the concentration of this solution is
A) 0.200 M (molar) B) 2.00 M (molar) C) 7.30 M (molar ) D) 2.00 m (molal)
E) 7.30 m (molal)
70. 2 NO(g) + O2(g) = 2 NO2(g)
2 N2O5(g) =
4 NO2(g) + O2(g)
K1
K2
4 NO(g) + 3 O2(g) = 2 N2O5(g)
K3
Given the equations as written above, and their equilibrium constants, K3 is equal to
A) K1K2 B) 2 K1 – K2 C) (K1)2/K2
D) K1/K2 (K1)2K2
Error!
71.For which of the following reactions occurring at equilibrium is the amount of product
formed NOT influenced by the total pressure when the temperature remains unchanged?
A) COCl2(g)  CO(g) + Cl2(g)
B) 2 NO(g) + O2  2 NO2(g)
C) PCl5(g)  PCl3(g) + Cl2(g)
D) 4 NH3(g) + 5 O2(g)  4 NO(g) + 6 H2O(g)
E) H2(g) + CO2(g)  H2O(g) + CO(g)
72. Which of the following ions can react either as an oxidizing agent or as a reducing agent?
A) Fe2+ B) Na+
C) SO42– D) O2– E) H–
73. What weight of copper can be plated out from a solution of CuSO4 by 3.0 faradays of
electricity?
1
2
3
A) ( 64) grams B ) ( 64) grams C ) ( 64) grams
2
3
2
D ) 2( 64) grams E ) 3( 64) grams
74. Which is the strongest Lewis acid? A) CH3COO–
B) Cl–
C) Al
D) Mg2+ E) N2
75. Which of the following metals displays the largest range of oxidation states?
A) Sc B) Zn C) Mn D) Ni E) Cu
76. If 0.15 mole of K2CO3 and 0.10 mole of KBr are dissolved in sufficient water to make
0.20 liter of solution, what is the molar concentration of K+ ? A) 0.080 M
B) 0.25 M
C) 0.40 M D) 2.0 M
E) 4.0 M
77. A laboratory preparation of NH3 gas involves the heating of an ammonium salt with
A) HCl B) H2SO4 C) KOH D) KCl E) NaHCO3
78. In a given experiment, 2.624 grams of Li2O was obtained from the reaction of 1.388 grams
of Li with excess O2. What is the % yield ? (Atomic mass of Li is 6.94, Formula mass of
Li2O is 29.9 ) A) 43.9 % B) 52.9 % C) 87.8 % D) 93.9 % E) 101.2 %
79. A 0.20 molar solutoin of a weak monoprotic acid, HA, has a pH of 3.00 . The ionization
constant of this acid is A) 5.0 x 10–7 B) 2.0 x 10–7 C) 5.0 x 10–6
D) 5.0 x 10–3 E) 2.0 x 10–3
80. Which of the following ions is paramagnetic ? A) K+ B) Ca2+ C) Cr2+ D) Zn2+ E) Sc3+
81. In a square planar complex such as PtCl2(NH3)2 the number of geometric isomers is
A) 2 B) 3 C) 4 D) 5 E) 6
82. An aqueous solution is 50. % by mass methanol, CH3OH. What is the mole fraction of the
methanol? A) 0.16 B) 0.36 C) 0.50 D) 0.56 E) 0.64
83. A disproportionation (self oxidation reaction) is illustrated by which of the following net
ionic equations? A) HCO3– + H+  H2O + CO2
B) Cu(H2O)42+ + 4 NH3  Cu(NH3)42+ + 4 H2O
C) 3 Ba2+ + 6 OH– + 2 Al3+ + 3 SO42–  2 Al(OH)3 + 3 BaSO4
D) 2 Mn3+ + 2 H2O  MnO2 + Mn2+ + 4 H+
E) Cr2O72– + 6 Fe2+ + 14 H+  2 Cr3+ + 6 Fe3+ + 7 H2O
84. For which of the following molecules is resonance considered LEAST relevant in
explaining the geometry and bond lengths? A) SO3 B) SO2
D) CO32– E) CO2
C) C6H6 (benzene)
85. Which of the following can be carried out in a closed system without risk of explosion?
I. Magnesium reacting with hydrochloric acid
II. Sodium hydrogencarbonate reacting with sulfuric acid
III. Iron (II) sulfate reacting with potassium permanganate solution
A) I only B) III only C) I and II only D) II and III only E) I, II, and III
86. Which of the following statements is true for the equilibrium vapor pressure of a liquid in a
closed system? A) It remains constant when the temperature increases B) It decreases to half its
original value if the volume of the gas phase is doubled C) It increases to twice its original value if
the volume of the liquid phase is doubled D) It decreases to half its original value if the surface area
of the liquid is reduced by one half E) It is independent of the volume of the vapor phase
87. At what concentration does a solution of HOCl (Ka = 3.0 x 10–8 ) have a concentration of
H3O+ = 2.0 x 10–5 M ? A) 2.0 x 10–5 M B) 1.7 x 10–4 M C) 1.5 x 10–3 M
D) 1.3 x 10–2 M E) 0.30 M
88. Which of the following is the strongest acid? A) Mg(OH)2 B) NaH
D) CH3COOH E) HClO3
C) C2H5OH
89. Equal volumes of 0.10 molar Ca(NO3)2 solution and 0.20 molar NaNO3 solution are mixed.
The molarity of the combined nitrate ion after mixing is A) 0.05 M B) 0.10 M C) 0.15 M
D) 0.20 M E) 0.30 M
90. The specific rate constant k for a radioactive element X is 0.023 min–1 . What weight of
X was originally present in a sample if 40. grams is left after 60 minutes?
A) 10 g B) 20 g C) 80 g D) 120 g E) 160 g
91. A weak monoprotic acid was titrated with a strong base with the use of a pH meter. The
titration curve of pH versus volume of base added was plotted using the data obtained. What further
information, if any, is needed to determine the Ka of this acid?
A) The initial volume of the acid solution B) The initial concentration of the monoprotic acid
C) The concentration of the base used D) The ion product of water, Kw
E) No further information is needed
92. Listed below are five compounds and their solubility product constants at 18̊ C.
Which has the lowest molar solubility at that temperature?
Compounds
Ksp
A) AgBr
3.3 x 10–13
B) BaCrO4
1.6 x 10–10
C) CaSO4
1.6 x 10–5
D) La(OH)3
1.0 x 10–19
E) PbCl2
1.7 x 10–5
93. Under the same conditions, what is the ratio of the rate of effusion of CO2 (MW=44) to the
rate of effusion of SF6 gas (MW = 146) A) 11
B) 3.32 C) 1.82 D) 0.549 E) 0.301
94. 2 NH4+ + CO32–  2 NH3 + H2O + CO2
Which statement about the reaction above is correct?
A) carbonate ion functions as a Brønsted-Lowry base B) ammonium ion functions as an
oxidizing agent C) carbonate ion is oxidized D) carbonate ion is reduced
E) the acid conjugate to NH3 is water
95. When a dilute solution of K2SO4 is electrolyzed with inert electrodes, the most likely
products at the two electrodes are A) H2 and O2 B) K and SO4 C) H2 and SO2
D) S8 and O2 E) K and SO2
96. The solubility product for PbI2 is 1 x 10–8. Ksp = [Pb2+][I–]2 In a KI solution that is
saturated with PbI2, the concentration of iodide ions is 1 x 10–3 molar. What is the
concentration of lead ions in this solution? A) 10–11 M B) 10–8 M C) 10–5 M
D) 10–3 M E) 10–2 M
97. After 295 days 71.0 % of a certain radioactive isotope has decayed. What is the half life of
this isotope? A) 165 days B) 194 days C) 195 days D) 329 days E) 595 days