Question 1
Question
Which one of the following pairs cannot be mixed together to form a buffer solution?
Answer
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A) HONH2, HONH3Cl
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B) NaCl, HCl
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C) RbOH, HF
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D) KOH, HNO2
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E) H2SO3, KHSO3
Question 2
Question
Which one of the following pairs cannot be mixed together to form a buffer solution?
Question 3
Question
A solution containing which one of the following pairs of substances will be a buffer solution?
Answer
-
A) NaI, HI
-
B) KBr, HBr
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C) RbCl, HCl
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D) CsF, HF
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E) none of the above
Question 4
Question
What change will be caused by addition of a small amount of HCl to a solution containing fluoride ions and hydrogen fluoride?
Answer
-
A) The concentration of hydronium ions will increase significantly.
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B) The concentration of fluoride ions will increase as will the concentration of hydronium ions.
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C) The concentration of hydrogen fluoride will decrease and the concentration of fluoride ions will increase.
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D) The concentration of fluoride ion will decrease and the concentration of hydrogen fluoride will increase.
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E) The fluoride ions will precipitate out of solution as its acid salt.
Question 5
Question
In a solution, when the concentrations of a weak acid and its conjugate base are equal,
Answer
-
A) the system is not at equilibrium.
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B) the buffering capacity is significantly decreased.
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C) the -log of the [H+] and the -log of the Ka are equal.
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D) all of the above are true.
Question 6
Question
Of the following solutions, which has the greatest buffering capacity?
Answer
-
A) 0.521 M HC2H3O2 and 0.217 M NaC2H3O2
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B) 0.821 M HC2H3O2 and 0.713 M NaC2H3O2
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C) 0.365M HC2H3O2 and 0.497 M NaC2H3O2
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D) 0.121 M HC2H3O2 and 0.116 M NaC2H3O2
Question 7
Question
) Of the following solutions, which has the greatest buffering capacity?
Answer
-
A) 0.543 M NH3 and 0.555 M NH4Cl
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B) 0.087 M NH3 and 0.088 M NH4Cl
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C) 0.234 M NH3 and 0.100 M NH4Cl
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D) 0.100 M NH3 and 0.455 M NH4Cl
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E) They are all buffer solutions and would all have the same capacity.
Question 8
Question
The addition of hydrofluoric acid and __________ to water produces a buffer solution.
Answer
-
A) HCl
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B) NaNO3
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C) NaF
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D) NaCl
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E) NaBr
Question 9
Question
The addition of sodium hydroxide and __________ to water produces a buffer solution.
Answer
-
A) HCl
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B) NaC2H3O2
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C) NaF
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D) NH3
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E) none of the above
Question 10
Question
Which of the following could be added to a solution of potassium fluoride to prepare a buffer?
Answer
-
A) sodium hydroxide
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B) potassium acetate
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C) hydrochloric acid
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D) sodium fluoride
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E) ammonia
Question 11
Question
A 25.0 mL sample of a solution of an unknown compound is titrated with a 0.115 M NaOH solution. The titration curve above was obtained. The unknown compound is __________.
Answer
-
A) a strong acid
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B) a strong base
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C) a weak acid
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D) a weak base
Question 12
Question
A 25.0 mL sample of a solution of a monoprotic acid is titrated with a 0.115 M NaOH solution. The titration curve above was obtained. The concentration of the monoprotic acid is about __________ mol/L.
Answer
-
A) 25.0
-
B) 0.0600
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C) 0.240
-
D) 0.120
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E) 0.100
Question 13
Question
A 25.0 mL sample of a solution of a monoprotic acid is titrated with a 0.115 M NaOH solution. The titration curve above was obtained. Which of the following indicators would be best for this titration?
Answer
-
A) methyl red
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B) bromthymol blue
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C) thymol blue
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D) phenolpthalein
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E) bromocresol purple
Question 14
Question
Which compound listed below has the greatest molar solubility in water?
Answer
-
A) CdCO3
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B) Cd(OH)2
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C) AgI
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D) CaF2
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E) ZnCO3
Question 15
Question
The molar solubility of __________ is not affected by the pH of the solution.
Answer
-
A) Na3PO4
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B) NaF
-
C) KNO3
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D) ACl3
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E) MnS
Question 16
Question
In which of the following aqueous solutions would you expect AgCl to have the lowest solubility?
Answer
-
A) pure water
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B) 0.020 M BaCl2
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C) 0.015 NaCl
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D) 0.020 AgNO3
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E) 0.020 KCl
Question 17
Question
In which one of the following solutions is silver chloride the most soluble?
Answer
-
A) 0.181 M HCl
-
B) 0.0176 M NH3
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C) 0.744 M LiNO3
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D) pure water
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E) 0.181 M NaCl
Question 18
Question
Which below best describe(s) the behavior of an amphoteric hydroxide in water?
Answer
-
A) With conc. aq. NaOH, its suspension dissolves.
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B) With conc. aq. HCl, its suspension dissolves.
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C) With conc. aq. NaOH, its clear solution forms a precipitate.
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D) With conc. aq. HCl, its clear solution forms a precipitate.
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E) With both conc. aq. NaOH and conc. aq. HCl, its suspension dissolves.
Question 19
Question
A result of the common-ion effect is __________.
Answer
-
A) that some ions, such as Na+ (aq), frequently appear in solutions but do not participate in solubility equilibria
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B) that common ions, such as Na+ (aq), don't affect equilibrium constants
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C) that the selective precipitation of a metal ion, such as Ag+, is promoted by the addition of an appropriate counterion (X-) that produces a compound (AgX) with a very low solubility
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D) that ions such as K+ and Na+ are common ions, so that their values in equilibrium constant expressions are always 1.00
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E) that common ions precipitate all counter-ions
Question 20
Question
The Ka of benzoic acid is 6.30 × 10-5. The pH of a buffer prepared by combining 50.0 mL of 1.00 M potassium benzoate and 50.0 mL of 1.00 M benzoic acid is __________.
Answer
-
A) 1.705
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B) 0.851
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C) 3.406
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D) 4.201
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E) 2.383
Question 21
Question
Calculate the pH of a solution prepared by dissolving 0.150 mol of acetic acid and 0.300 mol of sodium acetate in water sufficient to yield 1.00 L of solution. The Ka of acetic acid is 1.76 × 10-5.
Answer
-
A) 2.516
-
B) 3.892
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C) 4.502
-
D) 10.158
-
E) 5.056
Question 22
Question
The pH of a solution prepared by dissolving 0.350 mol of solid methylamine hydrochloride (CH3NH3Cl) in 1.00 L of 1.10 M methylamine (CH3NH2) is __________. The Kb for methylamine is 4.40 × 10-4. (Assume the final volume is 1.00 L.)
Answer
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A) 1.66
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B) 2.86
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C) 10.28
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D) 11.14
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E) 10.61
Question 23
Question
A 25.0 mL sample of 0.723 M HClO4 is titrated with a 0.27 M KOH solution. The H3O+ concentration after the addition of 80.0 mL of KOH is __________ M.
Answer
-
A) 0.0333
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B) 1 × 10-7
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C) 0.7
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D) 3 × 10-13
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E) 4 × 10-2
Question 24
Question
The pH of a solution prepared by mixing 50.0 mL of 0.125 M KOH and 50.0 mL of 0.125 M HCl is __________.
Answer
-
A) 6.29
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B) 7.00
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C) 8.11
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D) 5.78
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E) 0.00
Question 25
Question
The pH of a solution prepared by mixing 40.0 mL of 0.125 M Mg(OH)2 and 150.0 mL of 0.125 M HCl is __________.
Answer
-
A) 6.29
-
B) 4.11
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C) 1.14
-
D) 5.78
-
E) 1.34
Question 26
Question
The pH of a solution prepared by mixing 50.0 mL of 0.125 M NaOH and 40.0 mL of 0.125 M HNO3 is __________.
Answer
-
A) 13.29
-
B) 7.00
-
C) 8.11
-
D) 11.00
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E) none of the above
Question 27
Question
A 50.0 mL sample of an aqueous H2SO4 solution is titrated with a 0.375 M NaOH solution. The equivalence point is reached with 62.5 mL of the base. The concentration of H2SO4 is __________ M.
Answer
-
A) 0.234
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B) 0.469
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C) 0.150
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D) 0.300
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E) 0.938
Question 28
Question
The concentration of iodide ions in a saturated solution of lead (II) iodide is __________ M. The solubility product constant of PbI2 is 1.4 × 10-8.
Answer
-
A) 3.8 × 10-4
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B) 3.0 × 10-3
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C) 1.5 × 10-3
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D) 3.5 × 10-9
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E) 1.4 × 10-8
Question 29
Question
Calculate the percent ionization of formic acid (HCO2H) in a solution that is 0.311 M in formic acid and 0.189 M in sodium formate (NaHCO2). The Ka of formic acid is 1.77 × 10-4.
Answer
-
A) 37.8
-
B) 0.0937
-
C) 11.3
-
D) 1.06 × 10-3
-
E) 3.529
Question 30
Question
A solution is prepared by dissolving 0.23 mol of hydrofluoric acid and 0.27 mol of sodium fluoride in water sufficient to yield 1.00 L of solution. The addition of 0.05 mol of HCl to this buffer solution causes the pH to drop slightly. The pH does not decrease drastically because the HCl reacts with the __________ present in the buffer solution. The Ka of hydrofluoric acid is 1.36 × 10-3.
Question 31
Question
A solution is prepared by dissolving 0.23 mol of hydrazoic acid and 0.27 mol of sodium azide in water sufficient to yield 1.00 L of solution. The addition of 0.05 mol of NaOH to this buffer solution causes the pH to increase slightly. The pH does not increase drastically because the NaOH reacts with the __________ present in the buffer solution. The Ka of hydrazoic acid is 1.9 × 10-5.
Question 32
Question
Consider a solution containing 0.100 M fluoride ions and 0.126 M hydrogen fluoride. The concentration of fluoride ions after the addition of 4.00 mL of 0.0100 M HCl to 25.0 mL of this solution is __________ M.
Answer
-
A) 0.0862
-
B) 0.0876
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C) 0.0980
-
D) 0.0848
-
E) 0.00253
Question 33
Question
The Ka of acetic acid is 1.76 × 10-5. The pH of a buffer prepared by combining 45.0 mL of 1.00 M potassium acetate and 50.0 mL of 1.00 M acetic acid is __________.
Answer
-
A) 1.705
-
B) 0.851
-
C) 3.406
-
D) 4.709
-
E) 2.383
Question 34
Question
The Kb of ammonia is 1.76 × 10-5. The pH of a buffer prepared by combining 50.0 mL of 1.00 M ammonia and 50.0 mL of 1.00 M ammonium nitrate is __________.
Answer
-
A) 4.632
-
B) 9.246
-
C) 4.742
-
D) 9.372
-
E) none of the above
Question 35
Question
How many milliliters of 0.0850 M NaOH are required to titrate 25.0 mL of 0.0720 M HBr to the equivalence point?
Answer
-
A) 21.2
-
B) 0.245
-
C) 3.92
-
D) 0.153
-
E) 29.5
Question 36
Question
A 25.0 mL sample of 0.150 M hydrazoic acid is titrated with a 0.150 M NaOH solution. What is the pH at the equivalence point? The Ka of hydrazoic acid is 4.50 × 10-4.
Answer
-
A) 11.72
-
B) 9.28
-
C) 4.72
-
D) 7.00
-
E) 8.80
Question 37
Question
A 25.0-mL sample of 0.150 M butanoic acid is titrated with a 0.150 M NaOH solution. What is the pH before any base is added? The Ka of butanoic acid is 1.5 × 10-5.
Answer
-
A) 2.83
-
B) 1.5 × 10-3
-
C) 4.82
-
D) 4.00
-
E) 1.0 × 104
Question 38
Question
A 25.0 mL sample of 0.150 M hypochlorous acid is titrated with a 0.150 M NaOH solution. What is the pH after 26.0 mL of base is added? The Ka of hypochlorous acid is 3.0 × 10-8.
Answer
-
A) 2.54
-
B) 11.47
-
C) 7.00
-
D) 7.51
-
E) 7.54
Question 39
Question
A 25.0-mL sample of 0.150 M hydrazoic acid is titrated with a 0.150 M NaOH solution. What is the pH after 13.3 mL of base is added? The Ka of hydrazoic acid is 1.9 × 10-5.
Answer
-
A) 4.45
-
B) 1.34
-
C) 3.03
-
D) 4.78
-
E) 4.66
Question 40
Question
A 25.0 mL sample of 0.723 M HClO4 is titrated with a 0.273 M KOH solution. The H3O+ concentration after the addition of 60.0 mL of KOH is __________ M.
Answer
-
A) 0.0181
-
B) 0.430
-
C) 0.0200
-
D) 0.273
-
E) none of the above
Question 41
Question
The pH of a solution prepared by mixing 45.0 mL of 0.183 M KOH and 25.0 mL of 0.145 M HCl is __________.
Answer
-
A) 1.314
-
B) 1.181
-
C) 0.00824
-
D) 12.819
-
E) 12.923
Question 42
Question
In which aqueous system is Pbl2 least soluble?
Answer
-
A) H2O
-
B) 0.5 M HI
-
C) 0.2 M HI
-
D) 1.0 M HNO3
-
E) 0.8 M KI
Question 43
Question
Suppose you have just added 100.0 ml of a solution containing 0.5000 moles of acetic acid per liter to 400.0 ml of 0.5000 M NaOH. What is the final pH? The Ka of acetic acid is 1.77 × 10-5.
Answer
-
A) 9.123
-
B) 4.877
-
C) 0.5229
-
D) 13.48
Question 44
Question
An assembly of a metal ion and the Lewis bases bonded to it is called a __________.
Answer
-
A) Complex Ion
-
B) Lewis Structure
-
C) Soluble compound
Question 45
Question
Metal oxides and hydroxides that are relatively insoluble in neutral water, but are soluble in both strongly acidic and strongly basic solutions are said to be __________.
Answer
-
A) amphiprotic
-
B) amphoteric
-
C) amphiphilic
-
D) amphipathic