Download A) I is TRUE, II is FALSE B) I is FALSE, II is TRUE C) I and II

1. I. Heat is released with an endothermic reaction
4. I. The heat of fusion of ice is greater than the heat of
vaporization of water
BECAUSE
BECAUSE
II. energy is released when bonds are formed.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
2. I. When hydrochloric acid and water are mixed to form a
solution, the entropy increases
BECAUSE
II. stronger hydrogen bonds are broken when ice is
changed into water than when water is changed into
stream.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
5. I. The solubility of solids in water increases with an
increase in temperature
II. energy is released.
BECAUSE
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a
correct explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
3. I. Steam condenses to water and releases heat
BECAUSE
II. the entropy increases.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a
correct explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
6. I. An exothermic reaction always has a negative G
II. the temperature remains constant during a phase
change.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a
correct explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
BECAUSE
II. heat is released when the reaction occurs.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
7. I. An endothermic reaction always has a positive G
10. I. A positive DH tells you that the reaction is
exothermic
BECAUSE
BECAUSE
II. heat is released when the reaction occurs.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
8. I. A positive DS represents a decrease in potential energy
BECAUSE
II. DS represents the difference in the entropy of the
products and the reactants.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
9. I. A positive DS tells you that the reaction must be
spontaneous
II. with a positive DH, the products have more energy
than the reactants.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
11. I. The activation energy of an exothermic reaction is
always less than that of the reverse reaction
BECAUSE
II. the products have more energy than the reactants.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
12. I. When propane is burned in air, energy is absorbed
BECAUSE
BECAUSE
II. entropy always increases when a reaction occurs.
II. the reaction is exothermic.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
13. I. When N 2(g) is heated, its potential energy increases
BECAUSE
II. temperature is a measure of average potential
energy.
A)
B)
C)
D)
I is TRUE, II is FALSE
I is FALSE, II is TRUE
I and II are BOTH FALSE
I and II are BOTH TRUE but II IS NOT a correct
explanation of I
E) I and II are BOTH TRUE and II IS a correct
explanation of I
14. If the specific heat capacity of a metal is .79 cal/g ° C
and an 8 gram block of the metal is heated so that the
temperature of the block is increased by 30° C, how
much energy did the metal absorb?
A) 0.34 cal
C) 4.7 cal
E) 189.6 cal
B) 3.0 cal
D) 157.3 cal
18. If the temperature of a 2 gram block of metal increases
by 10 ° C over the course of 30 minutes, and during that
time the block absorbs 100 calories from the
environment, what is the specific heat of the metal?
A) .05 ° C/(cal g)
C) 0.5 ° C/(cal g)
E) 5.0 ° C/(cal g)
B) .05 cal/(g ° C)
D) 0.5 cal/(g ° C)
19. Which would have the highest heat of fusion?
A) HF
B) HCl
C) HBr
D) HI
E) HAt
20. Which would have the lowest heat of fusion?
A) H2O
B) CO 2
C) MgO D) Li 2O E) NaCl
21. Lead, Pb
MM = 207.2
Heat of Fusion = 4.77 kJ•mol–1 Specific Heat = 0.134
J•g–1•° C–1.
How much heat is needed to convert 800. g of solid
lead, Pb, at 25 ° C, to molten lead at its melting point,
327 ° C?
A) 2.30 kJ
C) 36.2 kJ
E) 50.8 kJ
B) 32.4 kJ
D) 40.6 kJ
A) 2.01 kJ•mol–1
C) 12.0 kJ•mol–1
E) 18.1 kJ•mol –1
B) 6.02 kJ•mol–1
D) 15.0 kJ•mol–1
15. A beaker of water is heated for ten minutes. If the water
absorbs 370 calories and its temperature is raised from
25 ° C to 47 ° C, what is the mass of water contained in
22. Heat of Fusion of Water, H 2O = 340 J•g –1
the beaker?
What quantity of ice can be melted by 58,000 Joules?
A) 0.68 g
B) 5.95 g
A) 5.7 × 10 –3 g
B) 1.7 × 10 2 g
C) 16.8 g
D) 37.3 g
4
C) 5.8 × 10 g
D) 3.5 × 10 5 g
E) 81.4 g
E) 2.0 × 10 7 g
16. 10 grams of a metal with a specific heat capacity of
23. Molar Heat Of Fusion of Water, H2O = 6.02 kJ•mol –1
1.10 cal/g ° C are heated over a bunsen burner. If the
How much energy is required to melt 14.0 g of water?
temperature of the metal increases by 55 ° C, how much
A) 4.68 kJ
B) 6.02 kJ
energy did the metal absorb?
C) 7.74 kJ
D) 18.7 kJ
A) 55.0 cal
B) 60.5 cal
E) 84.3 kJ
C) 550.0 cal
D) 605.0 cal
24. Molar Heat of Fusion of Water, H 2O, is 6.02 kJ•mol–1
E) 760.0 cal
What is the energy required to melt 3.00 mol of ice?
17. The specific heat of a metal is .58 cal/g ° C. If a sample
of this metal absorbs 250 calories and its temperature
increases from 12° C to 40 ° C, what is the mass of the
sample?
A) 3.1 g
C) 10.8 g
E) 40.6 g
B) 5.2 g
D) 15.4 g
25. Which would have the highest heat of vaporization?
A) HF
B) HCl
C) HBr
D) HI
E) H2S
26. Which would have the lowest heat of vaporization?
A) H2O
B) CO 2
C) MgO D) Li 2O E) HF
27. Chloroform, CHCl3 MM = 119.6
Heat of Vaporization = 59.0 cal•g –1 1.000 cal = 4.184 J
What is the heat of vaporization, H vap, of CHCl3, in kJ•mol–1?
A) 1.64 kJ
C) 29.5 kJ
E) 426 kJ
B) 2.13 kJ
D) 59.0 kJ
28. Acetone, (CH3) 2CO
MM = 58.3
Heat of Vaporization = 537 J•g–1
What mass of acetone can be vaporized by the
absorption of 12.5 kJ of heat?
A) 23.3 g
C) 537 g
E) 12,500 g
B) 43.0 g
D) 860 g
29. Ethyl alcohol, CH3CH 2OH
MM = 46.2
Heat of Vaporization = 881 J•g–1
How much heat is evolved when 1.25 kg of C2H5OH(g)
condenses to C2H5OH(l) at its normal boiling point?
A) 0.881 kJ
C) 23.8 kJ
E) 110 kJ
B) 1.10 kJ
D) 50.9 kJ
30. Diethyl ether, (CH 3CH 2) 2O
MM = 74.1
Heat of Vaporization = 27.8 kJ•mol–1 Specific Heat =
2.30 J•g–1•° C–1
How many kJ are needed to convert 100. g of liquid
diethyl ether, CH3CH 2OCH2CH 3 at 20° C, to gaseous
diethyl ether at its boiling point, 30 ° C?
A) 2.30 kJ
C) 37.5 kJ
E) 39.8 kJ
B) 34.2 kJ
D) 38.9 kJ
31. Heat of Vaporization of Ethanol, CH 3CH 2OH = 880. J•g
–1
.
How many Joules are needed to vaporize 2.00 g of
liquid ethanol, CH3CH 2OH, at its boiling point, 78 ° C?
A) 557 J
C) 880 J
E) 3360 J
B) 673 J
D) 1760 J
32. When an endothermic reaction occurs in a water
solution, the temperature of the solution
A)
B)
C)
D)
increases since energy is released by the reaction
decreases since energy is released by the reaction
increases since energy is absorbed by the reaction
decreases since energy is absorbed by the
reaction
E) remains the same
33. Which phase change is exothermic?
A) NH 3(g) ® NH 3(l)
C) H2O(s) ® H2O(l)
E) HF(l) ® HF(g)
B) CO 2(s) ® CO 2(g)
D) H2S(l) ® H2S(g)
34. Which phase change absorbs energy?
A) crystallizing H2O(l) B) melting H2O(s)
C) freezing H2O(l)
D) condensing H 2O(g)
E) none of the above
35. When a substance dissolves in water, the temperature of
the water decreases. This process is
A)
B)
C)
D)
E)
exothermic, with a release of energy
endothermic, with a release of energy
exothermic, with an absorption of energy
endothermic, with an absorption of energy
isothermic, with an increase in total energy
36. When a mixture of barium hydroxide, Ba(OH) 2, and
ammonium thiocyanate, NH4SCN, is mixed in a beaker,
it gets so cold that a moistened block of wood freezes
to the bottom of the beaker. This shows that this
reaction is
A)
B)
C)
D)
E)
exothermic and evolves energy
exothermic and absorbs energy
endothermic and evolves energy
endothermic and absorbs energy
none of the above
37. When an exothermic reaction occurs in a water
solution, the temperature of the solution
A) increases since energy is released by the
reaction
B) decreases since energy is released by the reaction
C) increases since energy is absorbed by the reaction
D) decreases since energy is absorbed by the reaction
E) remains the same
38. Which phase change is exothermic?
A) NH 3(s) ® NH 3(l) B) CO 2(s) ® CO 2(g)
C) H 2O(g) ® H 2O(l) D) H2S(s) ® H2S(g)
E) H2O(l) ® H2O(g)
39. Which phase change releases energy?
A) boiling H2O(l)
B) melting H 2O(s)
C) evaporating H 2O(l) D) subliming H 2O(s)
E) condensing H2O(g)
45. A decrease in the potential energy of a molecule occurs
as
A)
B)
C)
D)
E)
40. When a substance dissolves in water, the temperature of
the water increases. This process
A)
B)
C)
D)
E)
is exothermic, with a release of energy
is endothermic, with a release of energy
is exothermic, with an absorption of energy
is endothermic, with an absorption of energy
can be either exothermic or endothermic
41. When sulfuric acid, H 2SO 4, is added to water in a
beaker, the container and its contents get hot. This
shows that the solution reaction is
A)
B)
C)
D)
E)
exothermic and evolves energy
exothermic and absorbs energy
endothermic and evolves energy
endothermic and absorbs energy
none of the above
the substance sublimes
the volume is decreased
the pressure is increased
the substance condenses
two different compounds are mixed together
46. The greatest reduction of the average kinetic energy of
water molecules occurs when the water is
A)
B)
C)
D)
E)
cooled as a gas
cooled as a solid
cooled as a liquid
converted from a gas to a liquid
converted from a liquid to a solid
47.
42.
At which time is the kinetic energy highest?
During which segment of the graph is the potential
energy change the greatest?
A) AB
B) BC
C) CD
D) DE
E) EF
43. The greatest reduction of the average potential energy
of water molecules occurs when the water is
A)
B)
C)
D)
E)
cooled as a gas
cooled as a solid
cooled as a liquid
converted from a gas to a liquid
converted from a liquid to a solid
44. Which water sample has the greatest potential energy?
A)
B)
C)
D)
E)
H2O(s)
H2O(l)
H2O(aq)
H 2O(g)
The potential energies are equal.
A)
B)
C)
D)
E)
P
Q
R
S
It is impossible to determine from this diagram.
48. The temperature of a sample of carbon dioxide gas is a
measure of its
A)
B)
C)
D)
E)
total potential energy
average kinetic energy
average potential energy
total kinetic energy
kinetic and potential energy
49. Which illustrates the temperature–time graph for the
heating of ice at –10 ° C to produce steam at 125 ° C?
A)
B)
C)
D)
54. Fifty grams (50.0 g) of water is heated from 18.0 ° C to
32.0 ° C. How much heat is absorbed?
A) 2,930 J
C) 5,230 J
E) 6,690 J
B) 3,770 J
D) 5,960 J
55. To what temperature in Kelvin does 273 ° C correspond?
50. Which formula is used to change a temperature reading
from the Kelvin scale to the Celsius scale?
A) ° C = K + 273
B) ° C = K × 273
100
C) ° C = K × 100
273
D) ° C = K – 273
E) ° C = K + 273
100
A)
B)
C)
D)
E)
0 °C
0K
–273 K
the temperature at which water freezes
–273 ° F
52. Freezing Points
Hg 234 K
Cd 594 K
A temperature scale is devised using the freezing point
of mercury as 0° N and the freezing point of cadmium
as 100 ° N. How many Kelvins correspond to 90 ° N?
A) 324 K
C) 558 K
E) 644 K
B) 527 K
D) 597 K
53. Which is a chemical change?
A)
B)
C)
D)
E)
B) 32 K
D) 546 K
56. In any chemical reaction, energy is
51. The expression absolute zero refers to
A)
B)
C)
D)
E)
A) 0 K
C) 273 K
E) 646 K
freezing water
burning magnesium
magnetizing iron
liquefying oxygen
breaking glass
always absorbed
always released
usually not involved
never conserved
either absorbed or released
57. How much heat is absorbed when 50.0 grams of water
is heated from 22.0 ° C to 36.0 ° C?
A) 1,510 J
C) 4,520 J
E) 15,060 J
B) 2,930 J
D) 7,530 J
58. Which Celsius temperature is equivalent to 298 K?
A) 25 ° C
C) 398 ° C
E) 596 ° C
B) 212 ° C
D) 521 ° C
59. Water in changing from a solid to a gas through the
three physical states would normally undergo
A)
B)
C)
D)
E)
a change in mass
no energy changes
a change in density
a change in composition
a change in chemical properties
60. Mg(s) + 2 H+(aq) ® Mg 2+(aq) + H 2(g)
The above equation shows that
A)
B)
C)
D)
E)
Mg is less active than H 2
Mg is more stable than Mg2+
one mole of Mg reacts with one mole of H +
one mole of Mg liberates one mole of H 2
Mg(s) reacts spontaneously with H2(g)
61. Air pressure is graphed as a function of temperature.
The extrapolated line intersects the horizontal axis at
about –280° C. Which term is applied to this
temperature value?
A) Triple point
C) Freezing point
E) Absolute zero
B) Boiling point
D) Critical temperature
A) 20.4 kJ
C) 81.4 kJ
E) 1470 kJ
B) 76.7 kJ
D) 408 kJ
66. Energy that binds together ionic solids
A) A
B) B
C) C
D) D
E) E
67. Base your answer to the following question on the
diagram shown below.
Which represents the heat of reaction?
A) 1
B) 2
C) 3
D) 4
E) 5
62. In an exothermic reaction, the temperature of a l00
68. CuO + H2 ® Cu + H 2O(l) DH= –130.6 kJ
gram water bath is raised 5° C. How many calories does
What is the value of DH if the reaction produced water
the water absorb?
vapor instead of liquid water? ( DH = 44 kJ/mol for the
A) 5
B) 20
C) 50
D) 100 E) 500
phase change H 2O(l) ® H2O(g))
63. What is the Kelvin equivalent of –173 ° C?
A) –86.6 kJ
B) –174.6 kJ
A) –173 K
B) –100 K
C) 174.6 kJ
D) 126.6 kJ
C) 100 K
D) 200 K
E) 42.6 kJ
E) 446 K
69. Which of the following graphs represents an
64. The heat of vaporization of water is 40.7 kJ•mol –1.
exothermic reaction with a low activation energy?
How much energy is released when 36.0 g of steam
A)
B)
condenses into liquid water at 100ºC?
Base your answer to questions 65 and 66 on the
following types of energy.
(A) Lattice energy
(B) Potential energy
(C) Kinetic energy
(D) Electromagnetic energy
(E) Vaporization energy
65. Energy that can be used to directly calculate H
A) A
B) B
C) C
D) D
E) E
C)
D)
70.
H2O(l) ® H2O(s)
When water freezes at its normal boiling point of 0 oC,
which of the following is NOT true?
A)
B)
C)
D)
E)
71.
The volume decreases.
The heat is released.
The enthalpy decreases.
The entropy decreases.
The process is exothermic.
H2O(l) ® H2O(g)
When water boils at its normal boiling point of 100 oC,
which of the following is true?
A)
B)
C)
D)
E)
DH < 0, DS > 0, DV < 0
DH < 0, DS < 0, DV < 0
DH > 0, DS > 0, DV < 0
DH < 0, DS < 0, DV > 0
D H > 0, D S > 0, D V > 0
72. The heat of combustion for CH6O2N2(g) is –98 kcal.
CH 6O2N2(g) + O2(g) ® CO 2(g) + 2 NO 2(g) + 3 H2O(g)
What is the heat of formation for CH6O2N2(g)?
A) –216 kcal
C) 182 kcal
E) –124 kcal
B) –182 kcal
D) +124 kcal
73.
Based on the table above, what is the DHº for the reaction N2O4 + O2 ® N2O5?
A) –67.0 J
B) –14.8 J
C) –1.30 J
74. C2H6(g) + O2(g) ® 3 H2O(l) + 2 CO2(g)
What is the enthalpy change ( DH) for the above
reaction?
A) D E + RT
C) DE – RT
E) DE
B) DE – RT
D) DE + RT
D) +1.30 J
E) +14.8 J
75. In which of the following reactions would there be the
least difference between enthalpy change ( DH) and the
internal energy change ( DE)?
A)
B)
C)
D)
E)
CH 4(g) + Cl 2(g) ® CH 3Cl(g) + HCl(g)
2 NO(g) + O2(g) ® 2 NO 2(g)
C3H8(g) + 5 O2(g) ® 3 CO 2(g) + 4 H2O(g)
3 O2(g) ® 2 O3(g)
3 H2(g) + N2(g) ® 2 NH 3(g)
76. In which of the following reactions would there be the
greatest difference between enthalpy change ( DH) and
the internal energy change ( DE)?
A)
B)
C)
D)
E)
CH 4(g) + 3 O2(g) ® CO 2(g) + 2 H2O(g)
2 FeO(s) + 2 O2(g) ® Fe2O 3(s)
H2(g) + F 2(g) ® 2 HF(g)
CH 4(g) + 2 F 2(g) ® CF4(g) + 2 H2(g)
CO 2(g) + CaO(s) ® CaCO 3(s)
81. Two substances, A and B were separated after being in
solution by distillation. Distillation works because A
and B have different
A) crystal colors
C) densities
E) melting points
B) solubilities
D) boiling points
82. An experiment is designed to determine the enthalpy
(heat) of solution of ammonium chloride, NH4Cl.
77. C2H4(g) + 3 O2(g) ® 2 H2O(l) + 2 CO2(g)
What is the DH for the above reaction?
A) D E + 2RT
C) DE
E) DE – RT
B) DE – 2RT
D) DE + RT
78. 2 C2H2(g) + 3 O2(g) ® 4 CO2(g) + 2 H2O(l);
DHf º C2H2(g) = 54.20 kJ/mol
DHf º H2O(l) = –68.30 kJ/mol
DHf º CO2(g) = –94.10 kJ/mol
What is the standard enthalpy change for this reaction?
A) –216.6 kJ
C) –310.8 kJ
E) –621.6 kJ
B) –621.6 kJ
D) 310.8 kJ
79. Mass of container: 11.0 grams
Mass of solid sample plus container: 31.0 grams
Volume of the solid sample: 20.0 cubic centimeters
The density of the solid sample referred to above
should be reported as
A) 1.550 g/cm3
C) 1.0 g/cm3
E) 1.000 g/cm3
B) 1.55 g/cm3
D) 1.00 g/cm3
80. Which of the following is something not to do, or is
unnecessary when performing a titration?
A) Keeping the solution well mixed by constant
stirring
B) Rinsing the beaker that is to hold the solution
to be titrated right before pouring the solution
in
C) Draining the pipet by touching the tip to the side
of the container that is catching
D) Turning the stopcock immediately so that the
titration stops when the indicator changes color
E) Keeping track of the volume of the solution in the
buret both at the beginning of the experiment and
after the titration
Which will increase the precision of the heat of solution
of NH 4Cl the most?
A) Measure the temperatures to the nearest 0.01 ° C
B) Determine the mass of the NH 4Cl to the nearest 0.001 g.
C) Use a sample of NH 4Cl with a mass closer to
9.00 g rather than 8.00 g.
D) Determine the mass of the solution in the
calorimeter to the nearest 0.01 g.
E) Determine the mass of empty calorimiter to the
nearest 0.0001 g.
83. A student is to standardize a 0.5 M solution of KOH by titration. The following materials are available to
the student.
Clean, dry 50 mL buret Analytical balance; 250. mL Erlenmeyer flask; Wash bottle filled with distilled
water; Phenolphthalein indicator solution; Potassium hydrogen phthalate, KHP, a pure solid monoprotic
acid (to be used as the primary standard)
(A) Briefly describe (step by step) the technique the student should use to standardize the KOH, using the
materials above.
(B) Describe (i.e, set up) the calculations required to determine the concentration of the KOH solution.
84. Which number contains exactly 5 significant digits?
–5
A) 5.02 × 10
C) 0.00003
E) 32312 × 10 52
B) 34100
D) 0.0782 × 10 –3
85. The most effective way of separating a solution of corn
oil and water is
A)
B)
C)
D)
E)
90. Based on the above table, list the acids in order of increasing acid strength.
Titrating the solution with a strong base
Paper chromatography
Decanting the corn oil
Evaporating the water
Electrolyzing the solution
86. The most effective way of recovering solid NaCl from a
water solution of NaCl is
A)
B)
C)
D)
E)
89. Describe an experimental set up, along with necessary
measurements and equations, that can be used to
determine the heat liberated when 1.00 mol of zinc
reacts with reacts with 2.00 mol of hydrochloric acid.
Evaporating the water
Decanting the NaCl
Filtering out the NaCl
Adding solid AgNO3
Allowing the solution to settle
87. Which of the following are proper laboratory
procedures?
I. Wait until hot objects have reached room
temperature before finding their mass.
II. Always rinse a buret with water before
adding a titrant.
III. When mixing solutions, always add water to
the acid.
A) I and II
C) I only
E) I, II, and III
A)
B)
C)
D)
E)
CH 3COOH, NH 4+, HIO 3
HIO 3, CH 3COOH, NH 4+
HIO 3, HIO 3, CH 3COOH
NH 4+, HIO 3, CH 3COOH
NH 4+, CH 3COOH, HIO 3
91. List the following 1.0 M solutions in order of
decreasing pH.
CaBr2 FeCl3 NaF
A) NaF, CaBr2, FeCl3 B) FeCl 3, CaBr2, NaF
C) CaBr2, NaF, FeCl3 D) FeCl 3, NaF, CaBr 2
E) CaBr2, FeCl 3, NaF
B) II and III
D) III only
88. A 0.300 gram sample of a weak, nonvolatile base, X, is dissolved in enough water to make 40.0 mL of
solution. This is titrated against standardized HCl. Predict how the calculation of the molar mass of X
would be affected by the following procedures. Explain your answers.
(a) After rinsing the buret with distilled water, it is filled with the standard HCl solution. (b) Extra water is added to the 0.300 gram sample of X.
(c) The indicator phenolphthalein is used to signal the endpoint.
(d) An air bubble passes through the tip of the buret.
92. What is the correct arrangement of the four 0.01 M
solutions in the order of increasing pH?
NH4Cl
A)
B)
C)
D)
E)
H2SO4 NA2SO4 HCl
NH 4Cl, H2SO 4, Na2SO 4, HCl
HCl, H 2SO 4, Na2SO 4, NH 4Cl
Na2SO 4, NH 4Cl, HCl, H2SO 4
NH 4Cl, Na2SO 4, HCl, H 2SO 4
H2SO 4, HCl, NH4Cl, Na2SO 4
93. HF(aq) + NH 3(aq) « NH 4+(aq) + F –(aq)
Which statement is true about the equilibrium reaction
above?
A) The reactants are favored because NH4+ and HF
are acids of equal strength.
B) The products are favored because NH 4+ is a
stronger acid than HF.
C) The reactants are favored because HF is a stronger
acid than NH 4+.
D) The reactants are favored because NH4+ is a
stronger acid than HF.
E) The products are favored because HF is a
stronger acid than NH 4+.
94.
HSe– + HTe– « H2Te + Se2– HTe– +Se2– « HSe–
+Te2–
If reactants are favored in both the above two reactions
then what is the order of acids from strongest to
weakest?
A) HSe–, HTe – , H2Te B) HSe–, H2Te, HTe –
C) H2Te, HTe –, HSe– D) H2Te, HSe –, HTe –
E) HTe –, HSe –, H 2Te
95. Which can never be a base?
A) SO 32–
C) HSO 3–
E) NH 4+
B) H2O
D) H2PO 4–
96. A molecule or ion is classified as a Lewis base if it
A)
B)
C)
D)
E)
receives an electron pair to form a bond
has resonance structures
donates an electron pair to form a bond
donates an electron to a water molecule
receives an electron from a water molecule
97. Which of the following ions would hydrolyze to
produce hydronium ions?
A) CaO
B) SO 2
C) MgO D) Na2O E) LiO
98. Consider the following salts:
I. NaF
II. NaClO4 III. NaHSO4
Which of these salts, when dissolved in water, would
form a basic solution?
A) I and III only
C) II and III only
E) I only
B) I and II only
D) I, II and III
99. Which of the following salts dissolves to produce a
basic aqueous solution?
A) LiF
C) NaHSO3
E) Li 2SO 4
B) KClO 4
D) NH 4NO 3
100. Which of the following 0.10 M solutions is basic?
A) LiCl
C) NaClO 4
E) HCl
B) K 3PO 4
D) NH 4NO 3
Answer Key
Thermochemistry
1.
B
37.
A
73.
D
2.
D
38.
C
74.
A
3.
D
39.
E
75.
A
4.
C
40.
A
76.
B
5.
D
41.
A
77.
A
6.
B
42.
D
78.
B
7.
C
43.
D
79.
D
8.
B
44.
D
80.
B
9.
C
45.
D
81.
D
10.
B
46.
A
82.
C
11.
A
47.
D
83.
12.
B
48.
B
13.
C
49.
B
14.
E
50.
D
15.
C
51.
B
16.
D
52.
C
17.
D
53.
B
18.
D
54.
A
19.
A
55.
D
20.
B
56.
E
21.
E
57.
B
22.
B
58.
A
23.
A
59.
C
24.
E
60.
D
25.
A
61.
E
26.
B
62.
E
27.
C
63.
C
28.
A
64.
C
29.
C
65.
B
30.
E
66.
A
31.
D
67.
A
32.
D
68.
A
33.
A
69.
D
34.
B
70.
A
35.
D
71.
E
36.
D
72.
E
(A) 4 essential steps:
1) Weigh KHP
2) Rinse buret with
small amount of
NaOH solution
3) Fill buret with
NaOH solution
4) Add indicator
(phenolphthalein)
5) Titrate to endpoint
(color change)
89.
90.
E
91.
A
92.
C
93.
E
94.
E
95.
E
96.
C
97.
(B) moles KHP =
Mass KHP/ MM KHP 98.
moles KHP = moles
99.
OH – at equivalence
100.
point and (moles OH–
/ liters KOH) = [OH–]
84.
E
85.
C
86.
A
87.
C
88.
(essay)
In a calorimeter, place
a known amount of
zinc into a solution of
excess HCl. Measure
the temperature
before and after the
reaction. Use the
formula
DH = mcalorimetercpDT to
determine the heat
released. Divide by
the number of moles
of zinc to get the
molar enthalpy
change.
B
E
A
B
Answer Key
Thermochemistry
88.
(a) The calculated molar mass will be too low. The droplets of water remaining in the buret will dilute the HCl
so that a larger volume is needed. This corresponds to a higher concentration for the basic solution and thus a
lower molar mass.
(b) No change. The amount of the acid used in the titration remains the same.
(c) The calculated molar mass would be too high. Less acid would be needed to reach the endpoint.
(d) The calculated molar mass would be too low. It would appear as if more acid was used in the titration.