Chapter 14 Review Questions
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General Chemistry: Atoms First, 2e (McMurry and Fay)Chapter 14 Aqueous Equilibria: Acids and Bases
14.1 Multiple Choice Questions
1) An Arrhenius acid is best defined as aA) hydroxide donor.B) proton acceptor.C) substance that dissociates in water to produce aqueous hydrogen ions.D) substance that dissociates in water to produce aqueous hydroxide ions.Answer: CDiff: 1Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
2) When dissolved in water, which of the following compounds is an Arrhenius acid?A) HCNB) NaOHC) NaFD) CH3CH2OHAnswer: ADiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry TheoryAlgo. Option: algorithmic
3) An Arrhenius base is best defined as aA) proton donor.B) hydroxide acceptor.C) substance that dissociates in water to produce aqueous hydrogen ions.D) substance that dissociates in water to produce aqueous hydroxide ions.Answer: DDiff: 1Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
4) When dissolved in water, which of the following compounds is an Arrhenius base?A) CH3OHB) HOClC) KOHD) KClAnswer: CDiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
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5) A Brønsted-Lowry acid is best defined as a substance that canA) accept a hydroxide ion.B) donate a hydroxide ion.C) accept a proton.D) donate a proton.Answer: DDiff: 1Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
6) Which one of the following species acts as a Brønsted-Lowry acid in water?A) NaHB) NH4+
C) CH3NH2D) C6H6Answer: BDiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
7) In the following chemical equation indicate the reactant that is a Brønsted-Lowry acidHCN(aq) + H2O(l) H⇌ 3O+(aq) + CN-(aq).
A) HCNB) H2O
C) H3O+
D) CN-Answer: ADiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
8) Indicate all the Brønsted-Lowry acids in the following chemical reactionHCl(aq) + H2O(aq) H⇌ 3O+(aq) + Cl-(aq).
A) HCl, H2OB) HCl, C) HCl, Cl-
D) HCl, H2O, H3O+
Answer: BDiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
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9) What are the Brønsted-Lowry bases in the following chemical reaction C5H5N(aq) + H2O(l) C⇌ 5H5NH+(aq) + OH-(aq)?
A) C5H5N, H2O
B) C5H5N, C5H5NH+
C) C5H5N,
D) C5H5N, H2O, OH-
Answer: CDiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
10) What are the Brønsted-Lowry acids in the following chemical reactionHBr(sol) + CH3COOH(sol) CH⇌ 3C(OH)2+(sol) + Br-(sol)?
A) HBr, CH3COOHB) HBr, C) CH3COOH, CH3C(OH)2+
D) CH3COOH, Br-
Answer: BDiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
11) What are the conjugate acid-base pairs in the following chemical reactionNH3(aq) + H2O(l) NH⇌ 4+(aq) + OH-(aq)?
A) NH3, H2O and NH4+, OH-
B) NH3, NH4+ and H2O, OH-
C) NH3, OH- and H2O, NH4+
D) NH3 and NH4+
Answer: BDiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
12) Identify the conjugate acid/base pairs present in an aqueous solution of hydrogen sulfate ion, HSO4-.
A) HSO4-/SO42- and H3O+/H2O
B) H2SO4/HSO4- and H2O/OH-
C) HSO4-/H2O and H3O+/SO42-
D) HSO4-/H2O and H2SO4/OH-
Answer: ADiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
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13) What is the conjugate base of the Brønsted-Lowry acid HPO42-?A) H3PO4B) H2PO4-
C) HPO42-
D) PO43-
Answer: DDiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
14) What is the conjugate acid of the Brønsted-Lowry base HAsO42-?
A) H2AsO4-
B) AsO43-
C) H2O
D) H3O+
Answer: ADiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
15) Which one of the following can behave either as a Brønsted-Lowry acid or a Brønsted-Lowry base in an aqueous solution reaction?A) HSO3-
B) NH3C) HID) H3PO4Answer: ADiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
16) Write a balanced equation for the dissociation of the Brønsted-Lowry acid HSO4- in water.
A) HSO4-(aq) + H2O(l) H⇌ 2SO4(aq) + OH-(aq)
B) HSO4-(aq) + H2O(l) SO⇌ 42-(aq) + H3O+(aq)
C) HSO4-(aq) + H2O(l) SO⇌ 32-(aq) + OH-(aq)
D) HSO4-(aq) + H2O(l) SO⇌ 3(g) + OH-(aq) + H2O(l)Answer: BDiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
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17) Which of the following Brønsted-Lowry acids does not behave as a strong acid when it is dissolved in water?A) HB) HClC) HNO2D) HClO4Answer: CDiff: 2Topic: Section 14.2 Acid Strength and Base StrengthAlgo. Option: algorithmic
18) Which Brønsted -Lowry base has the strongest conjugate acid?A) CH3CO2-
B) CN-
C) F-
D) NO3-
Answer: DDiff: 2Topic: Section 14.2 Acid Strength and Base Strength
19) Which Brønsted-Lowry acid has the strongest conjugate base?A) HClB) HClO4C) HFD) HAnswer: CDiff: 2Topic: Section 14.2 Acid Strength and Base Strength
20) What is the strongest Brønsted-Lowry acid in the chemical reaction shown below?2 HNO3(aq) + Ba(OH)2(aq) → Ba(NO3)2(aq) + 2 H2O(l)
A) HNO3B) Ba(OH)2C) Ba(NO3)2D) H2OAnswer: ADiff: 2Topic: Section 14.2 Acid Strength and Base Strength
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21) From the following chemical reactions determine the relative Brønsted-Lowry acid strengths (strongest to weakest).
HCl(aq) + H2O(l) → H3O+(aq) + Cl-(aq)
HCN(aq) + H2O(l) H⇌ 3O+(aq) + CN-(aq)
A) HCl > HCN > H3O+
B) HCl > H3O+ > HCN
C) H3O+ > HCl > HCN
D) HCN > H3O+ > HClAnswer: BDiff: 3Topic: Section 14.2 Acid Strength and Base Strength
22) From the following chemical reactions determine the relative Brønsted-Lowry acid strengths (strongest to weakest).
HClO4(aq) + H2O(l) → H3O+(aq) + ClO4-(aq)
HNO2(aq) + H2O(l) H⇌ 3O+(aq) + NO2-(aq)
A) HClO4 > H3O+ > HNO2B) HClO4 > HNO2 > H3O+
C) H3O+ > HClO4 > HNO2D) H3O+ > HNO2 > HClO4Answer: ADiff: 3Topic: Section 14.2 Acid Strength and Base Strength
23) From the following chemical reactions determine the relative Brønsted-Lowry acid strengths (strongest to weakest).
HClO4(sol) + CH3COOH(l) → CH3C2(OH)2+(sol) + ClO4-(aq)
H2SO4(sol) + CH3COOH(l) CH⇌ 3C(OH)2+(sol) + HSO4-(sol)A) HClO4 > H2SO4 > CH3COOH
B) HClO4 > H2SO4 > CH3C(OH)2+
C) HClO4 > CH3COOH > H2SO4D) HClO4 > CH3C(OH)2+ > H2SO4Answer: DDiff: 3Topic: Section 14.2 Acid Strength and Base Strength
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24) From the following chemical reactions determine the relative Brønsted-Lowry base strengths (strongest to weakest).
HNO3(aq) + H2O(l) → H3O+(aq) + NO3-(aq)
HF(aq) + H2O(l) H⇌ 3O+(aq) + F-(aq)
A) HNO3 > H3O+ > HF
B) NO3- > H2O > F-
C) F- > H2O > NO3-
D) F- > NO3- > H2OAnswer: CDiff: 3Topic: Section 14.2 Acid Strength and Base Strength
25) From the following chemical reactions determine the relative Brønsted-Lowry base strengths (strongest to weakest).
2 NaH(s) + H2O(l) → 2 NaOH + H2(g)
NH3(aq) + H2O(l) NH⇌ 4+(aq) + OH-(aq)
A) H- > OH- > NH3B) H- > NH3 > OH-
C) OH-> H- > NH3D) OH- > NH3 > H-
Answer: ADiff: 3Topic: Section 14.2 Acid Strength and Base Strength
26) The equilibrium constant, K, for the reaction shown below has a value 1.8 × 10–5. In this reaction which is the strongest acid and which is the strongest base?
CH3CO2H(aq) + H2O(l) H⇌ 3O+(aq) + CH3CO2–(aq)
A) CH3CO2H and CH3CO2– B) CH3CO2H and H2O
C) H3O+ and H2O
D) H3O+ and CH3CO2–
Answer: DDiff: 3Topic: Section 14.2 Acid Strength and Base Strength
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The following pictures represent aqueous solutions of binary acids of the type HA where the water molecules have been omitted for clarity.
27) Determine the strongest acid of the set.A) AB) BC) CD) DAnswer: BDiff: 2Topic: Section 14.2 Acid Strength and Base Strength
28) Arrange the acids in order of increasing acid strength.A) D < C < A < BB) D < C < B < AC) D < B < A < CD) D < A < C < BAnswer: DDiff: 3Topic: Section 14.2 Acid Strength and Base Strength
29) What is the geometric shape of the hydrated proton; that is, the hydronium ion H3O+?A) angularB) trigonal pyramidalC) trigonal planarD) tetrahedralAnswer: BDiff: 2Topic: Section 14.3 Factors That Affect Acid Strength
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30) An acidic solution at 25°C hasA) [H3O+] > [OH-] > 1 × 10-7 M.
B) [H3O+] > 1 × 10-7 M > [OH-].
C) [H3O+] = [OH-] > 1 × 10-7 M.
D) [H3O+] < 1 × 10-7 M > [OH-].Answer: BDiff: 1Topic: Section 14.4 Dissociation of Water
31) At 50°C the value of Kw is 5.5 × 10-14. A basic solution at 50°C has
A) [H3O+] < [OH-] < 2.3 × 10-7 M.
B) [H3O+] < 2.3 × 10-7 M < [OH-].
C) [H3O+] = [OH-] < 2.3 × 10-7 M.
D) [H3O+] > 2.3 × 10-7 M < [OH-].Answer: BDiff: 2Topic: Section 14.4 Dissociation of Water
32) Calculate the hydronium ion concentration in an aqueous solution that contains 2.50 × 10-4 M in hydroxide ion.A) 4.00 × 10-9 MB) 4.00 × 10-10 MC) 4.00 × 10-11 MD) 5.00 × 10-11 MAnswer: CDiff: 2Topic: Section 14.4 Dissociation of WaterAlgo. Option: algorithmic
33) Calculate the hydroxide ion concentration in an aqueous solution that contains 3.50 × 10-3 M in hydronium ion.A) 2.86 × 10-4 MB) 2.86 × 10-11 MC) 2.86 × 10-12 MD) 3.50 × 10-12 MAnswer: CDiff: 2Topic: Section 14.4 Dissociation of WaterAlgo. Option: algorithmic
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34) A solution with a hydrogen ion concentration of 3.25 × 10-2 M is ________ and has a hydroxide concentration of ________.A) acidic, 3.08 × 10-12 MB) acidic, 3.08 × 10-13 MC) basic, 3.08 × 10-12 MD) basic, 3.08 × 10-13 MAnswer: BDiff: 2Topic: Section 14.4 Dissociation of WaterAlgo. Option: algorithmic
35) A solution with a hydroxide ion concentration of 4.15 × 10-4 M is ________ and has a hydrogen ion concentration of ________.A) acidic, 2.41 × 10-10 MB) acidic, 2.41 × 10-11 MC) basic, 2.41 × 10-10 MD) basic, 2.41 × 10-11 MAnswer: DDiff: 2Topic: Section 14.4 Dissociation of WaterAlgo. Option: algorithmic
36) If the ionization constant of water, Kw, at 40°C is 2.92 × 10-14, then what is the hydronium ion concentration for a neutral solution?A) [H3O+] < 1.00 × 10-7 M
B) [H3O+] > 1.71 × 10-7 M
C) [H3O+] = 1.71 × 10-7 M
D) [H3O+] < 1.71 × 10-7 MAnswer: CDiff: 2Topic: Section 14.4 Dissociation of Water
37) An acidic solution at 25°C will have a hydronium ion concentration ________ and a pH value ________.A) [H3O+] > 1 × 10-7 M, pH > 7.00
B) [H3O+] > 1 × 10-7 M, pH < 7.00
C) [H3O+] < 1 × 10-7 M, pH > 7.00
D) [H3O+] < 1 × 10-7 M, pH < 7.00Answer: BDiff: 1Topic: Section 14.5 The pH Scale
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38) If the ionization constant of water, Kw, at 40°C is 2.92 × 10-14, then what is the hydronium ion concentration and pH for an acidic solution?A) [H3O+] > 1.71 × 10-7 M and pH > 6.77
B) [H3O+] > 1.71 × 10-7 M and pH < 6.77
C) [H3O+] < 1.71 × 10-7 M and pH > 6.77
D) [H3O+] < 1.71 × 10-7 M and pH < 6.77Answer: BDiff: 2Topic: Section 14.5 The pH Scale
39) Calculate the pH for an aqueous solution of acetic acid that contains hydronium ion.A) 4.65 × 10-12
B) 2.15 × 10-3C) 2.67D) 11.33Answer: CDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
40) Calculate the pH for an aqueous solution of pyridine that contains hydroxide ion.A) 4.65 × 10-11
B) 2.15 × 10-4 C) 3.67D) 10.33Answer: DDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
41) What is the hydroxide ion concentration and the pH for a hydrochloric acid solution that has a hydronium ion concentration of A) 6.67 × 10-10 M, 4.82B) 6.67 × 10-10 M, 9.18C) 6.67 × 10-11 M, 3.82D) 6.67 × 10-11 M, 10.18Answer: CDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
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42) What is the hydronium ion concentration and the pH for an aqueous solution of NH3 that has a hydroxide ion concentration ofA) 4.44 × 10-11 M, 3.65B) 4.44 × 10-11 M, 10.35C) 4.44 × 10-12 M, 2.65D) 4.44 × 10-12 M, 11.35Answer: DDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
43) What is the hydronium ion concentration of an acid rain sample that has a pH of 3.15?A) 1.41 × 10-11 MB) 7.08 × 10-4 M C) 3.15 MD) 10.85 MAnswer: BDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
44) What is the hydroxide ion concentration of a lye solution that has a pH of 11.20?A) 6.31 × 10-12 MB) 1.58 × 10-3 MC) 2.80 M D) 11.20 MAnswer: BDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
45) What statement is most consistent for an acid with a pH = 3?A) one one-hundredth as strong as an acid with a pH of 5B) half a strong as an acid with a pH = 5C) twice as strong as an acid with a pH of 5D) one hundred times as strong as an acid with a pH = 5Answer: DDiff: 2Topic: Section 14.5 The pH Scale
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46) At 25°C, the pH of a vinegar solution is 2.60. What are the values of [H3O+] and [OH-] in the solution?A) 3.99 × 10-12 M, 2.51 × 10-3 MB) 2.51 × 10-3 M, 3.98 × 10-12 MC) 2.51 × 10-3 M, 11.40 MD) 2.60 M, 11.40 MAnswer: BDiff: 2Topic: Section 14.5 The pH Scale
47) What is the approximate pH of a solution X that gives the following responses with the indicators shown?
IndicatorsHIn — In-
pH range
Solution X
methyl orange red-yellow 3.2-4.4 yellow
methyl red red-yellow 4.8-6.0 yellow
bromthymol blue yellow-blue 6.0-7.6 green
phenolphthalein colorless-pink 8.2-10.0 colorless
A) 3.2 - 4.4 B) 4.8 - 6.0 C) 6.0 - 7.6D) 8.2 - 10.0Answer: CDiff: 2Topic: Section 14.6 Measuring pH
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48) What is the approximate pH of a solution X that gives the following responses with the indicators shown?
IndicatorsHIn — In-
pH range
Solution X
methyl orange red-yellow 3.2-4.4 yellow
methyl red red-yellow 4.8-6.0 orange
bromthymol blue yellow-blue 6.0-7.6 yellow
phenolphthalein colorless-pink 8.2-10.0 colorless
A) 3.2 - 4.4B) 4.8 - 6.0C) 6.0 - 7.6D) 8.2 - 10.0Answer: BDiff: 2Topic: Section 14.6 Measuring pH
49) What is the approximate pH of a solution X that gives the following responses with the indicators shown?
IndicatorsHIn — In-
pH range
Solution X
methyl orange red-yellow 3.2-4.4 yellow
methyl red red-yellow 4.8-6.0 yellow
bromthymol blue yellow-blue 6.0-7.6 blue
phenolphthalein colorless-pink 8.2-10.0 pink
A) 4.8 - 6.0B) 6.0 - 7.6C) 7.6 - 8.2D) > 8.2Answer: DDiff: 2Topic: Section 14.6 Measuring pH
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50) What is the pH of a 0.020 M HClO4 solution?A) 0.020B) 0.040C) 1.70D) 12.30Answer: CDiff: 2Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
51) What is the pH of a 0.020 M RbOH solution?A) 0.020B) 0.040C) 1.70D) 12.30Answer: DDiff: 2Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong Bases
52) What is the pH of a 0.020 M Ba(OH)2 solution?A) 1.40B) 1.70C) 12.30D) 12.60Answer: DDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
53) What is the pH of a solution prepared by dissolving 0.15 gram of solid CaO (lime) in enough water to make 2.00 L of aqueous Ca(OH)2 (limewater)?
CaO(s) + H2O(l) → Ca2+(aq) + 2 OH-(aq)A) 2.57B) 2.87C) 11.13D) 11.43Answer: DDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
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54) What is the pH of a solution prepared by diluting 25.00 mL of 0.10 M HCl with enough water to produce a total volume of 100.00 mL?A) 1.00B) 1.60C) 2.00D) 3.20Answer: BDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
55) What is the pH of a solution prepared by diluting 25.00 mL of 0.020 M Ba(OH)2 with enough water to produce a total volume of 250.00 mL?A) 2.40B) 2.70C) 11.30D) 11.60Answer: DDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
56) What is the pH of a solution made by mixing 100.00 mL of 0.20 M HCl with 50.00 mL of 0.10 M HCl? Assume that the volumes are additive.A) 0.15B) 0.52C) 0.78D) 1.70Answer: CDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
57) What is the pH of a solution made by mixing 100.0 mL of 0.10 M HNO3, 50.0 mL of 0.20 M HCl, and 100.0 mL of water? Assume that the volumes are additive.A) 0.30B) 0.82C) 1.00D) 1.10Answer: DDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
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58) What is the pH of a solution prepared by mixing 100.00 mL of 0.020 M Ca(OH)2 with 50.00 mL of 0.100 M NaOH? Assume that the volumes are additive.A) 12.67B) 12.78C) 12.95D) 13.25Answer: BDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
59) What is the equilibrium constant expression (Ka) for the acid dissociation of hydrocyanic acid HCN? The equation of interest is
HCN(aq) + H2O(l) H⇌ 3O+(aq) + CN-(aq).
A) Ka = ([H3O+][CN-])/([HCN][H2O])
B) Ka = ([H3O+][CN-])/([HCN])
C) Ka = ([HCN][H2O])/([H3O+][CN-])
D) Ka = ([HCN])/([H3O+][CN-])Answer: BDiff: 2Topic: Section 14.8 Equilibria in Solutions of Weak Acids
60) What is the equilibrium constant expression (Ka) for the acid dissociation of nitrous acid HNO2? The equation of interest is
HNO2(aq) + H2O(l) H⇌ 3O+(aq) + NO2-(aq).
A) Ka = ([H3O+][NO2-])/([HNO2][H2O])
B) Ka = ([H3O+][NO2-])/([HNO2])
C) Ka = ([HNO2][H2O])/([H3O+][NO2-])
D) Ka = ([HNO2])/([H3O+][NO2-])Answer: BDiff: 2Topic: Section 14.8 Equilibria in Solutions of Weak Acids
61) Determine the acid dissociation constant for a 0.10 M acetic acid solution that has a pH of 2.87. Acetic acid is a weak monoprotic acid and the equilibrium equation of interest is
A) 1.3 × 10-2 B) 1.3 × 10-3
C) 1.8 × 10-5 D) 1.8 × 10-6Answer: CDiff: 3
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Topic: Section 14.8 Equilibria in Solutions of Weak Acids
62) Determine the acid dissociation constant for a 0.010 M nitrous acid solution that has a pH of 2.70. Nitrous acid is a weak monoprotic acid and the equilibrium equation of interest is
A) 8.0 × 10-3
B) 2.0 × 10-3
C) 5.0 × 10-4
D) 4.0 × 10-4Answer: CDiff: 3Topic: Section 14.8 Equilibria in Solutions of Weak Acids
63) Determine the acid dissociation constant for a 0.020 M formic acid solution that has a pH of 2.74. Formic acid is a weak monoprotic acid and the equilibrium equation of interest is
A) 1.8 × 10-3
B) 1.8 × 10-4
C) 3.6 × 10-4
D) 3.6 × 10-5Answer: BDiff: 3Topic: Section 14.8 Equilibria in Solutions of Weak Acids
64) The pH of 0.255 M HCN is 4.95. What is the value of Ka for hydrocyanic acid?
A) 1.3 × 10-10
B) 4.9 × 10-10
C) 1.1 × 10-5
D) 4.4 × 10-5Answer: BDiff: 3Topic: Section 14.8 Equilibria in Solutions of Weak Acids
65) The pH of 0.150 M CH3CO2H, acetic acid, is 2.78. What is the value of Ka for acetic acid?
A) 2.8 × 10-6
B) 1.9 × 10-5
C) 1.7 × 10-3
D) 1.1 × 10-2Answer: BDiff: 3Topic: Section 14.8 Equilibria in Solutions of Weak Acids
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66) What is the strongest monoprotic acid of the following set if all the acids are at 0.100 M concentration?A) hydrofluoric acid with Ka = 3.5 × 10-4
B) benzoic acid with Ka = 6.5 × 10-5
C) acetic acid with Ka = 1.8 × 10-5
D) hypochlorous acid with Ka = 3.5 × 10-8
Answer: ADiff: 1Topic: Section 14.8 Equilibria in Solutions of Weak Acids
67) What is the hydronium ion concentration of a 0.100 M acetic acid solution with a Ka = 1.8 ×
10-5? The equation for the dissociation of acetic acid is:CH3CO2H(aq) + H2O(l) ⇌ H3O+(aq) + CH3CO2-(aq).
A) 1.3 × 10-2 MB) 4.2 × 10-2 MC) 1.3 × 10-3 MD) 4.2 × 10-3 MAnswer: CDiff: 3Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak AcidsAlgo. Option: algorithmic
68) The p of HCN is 9.31. What is the pH of a 0.52 M solution of HCN?A) 4.80B) 5.20C) 6.79D) 6.33Answer: ADiff: 3Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak Acids
69) The of hypochlorous acid, HOCl, is 3.5 × . What is the pH of 0.78 M HOCl?A) 3.78B) 3.50C) 2.82D) 2.53Answer: ADiff: 3Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak Acids
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70) What is the p of hypobromous acid, HOBr, if a 0.40 M HOBr has a pH of 4.50?A) 8.60B) 4.50C) 6.11D) 4.92Answer: ADiff: 3Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak Acids
71) What is the hydronium ion concentration of a 0.100 M hypochlorous acid solution with The equation for the dissociation of hypochlorous acid is:
HOCl(aq) + H2O(l) ⇌ H3O+(aq) + OCl-(aq).
A) 1.9 × 10-4
B) 5.9 × 10-4
C) 1.9 × 10-5
D) 5.9 × 10-5Answer: DDiff: 3Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak AcidsAlgo. Option: algorithmic
72) Para-Aminobenzoic acid (PABA), p-H2NC6H4(COOH), is used in some sunscreens and hair conditioning products. Calculate the pH of an aqueous solution with and
A) 1.52B) 3.09C) 4.66D) 6.18Answer: BDiff: 3Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak Acids
73) A tablet containing 500.0 mg of aspirin (acetylsalicylic acid or was dissolved in enough water to make 100 mL of solution. Given that Ka = 3.0 × 10–4 for aspirin, what is the pH of the solution?A) 1.57B) 2.54C) 3.52D) 5.08Answer: BDiff: 4Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak Acids
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74) Benzoic acid (C6H5CO2H = HBz) solutions are sometimes used in experiments to determine the molarity of a basic solution of unknown concentration. What is the pH of a 0.100 M solution of benzoic acid if and the equilibrium equation of interest is
A) 1.00B) 2.59C) 4.19D) 5.19Answer: BDiff: 4Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak Acids
75) Potassium hydrogen phthalate (molar mass = 204.2 g/mol) is one of the most commonly used acids for standardizing solutions containing bases. KHP is a monoprotic weak acid with
Calculate the pH of the solution that results when 0.40 g of KHP is dissolved in enough water to produce 25.0 mL of solution.A) 2.10B) 3.26C) 4.30D) 5.41Answer: BDiff: 4Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak AcidsAlgo. Option: algorithmic
76) Vinegar is a 5.0% solution by weight of acetic acid (CH3CO2H) in water. Given that
for acetic acid and assuming the density of vinegar to be 1.00 g/cm3, what is the pH of this vinegar solution?A) 2.00B) 2.41C) 2.87D) 4.74Answer: BDiff: 4Topic: Section 14.10 Percent Dissociation in Solutions of Weak Acids
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77) Vinegar is a 5.0% solution by weight of acetic acid (CH3CO2H) in water. Given that the pH
for acetic acid is 2.41, the and assuming the density of vinegar to be 1.00 g/cm3, what is the percent dissociation of acetic acid in vinegar?A) 0.47%B) 1.5%C) 4.0%D) 5.0%Answer: ADiff: 4Topic: Section 14.10 Percent Dissociation in Solutions of Weak Acids
78) What is the percent dissociation of a benzoic acid solution with pH = 2.59? The acid dissociation constant for this monoprotic acid is A) 0.50%B) 1.5%C) 2.5%D) 3.5%Answer: CDiff: 4Topic: Section 14.10 Percent Dissociation in Solutions of Weak Acids
79) The percent dissociation of acetic acid changes as the concentration of the acid decreases. A 100-fold decrease in acetic acid concentration results in a ________ fold ________ in the percent dissociation.A) 10, increaseB) 10, decreaseC) 100, increaseD) 100, decreaseAnswer: ADiff: 3Topic: Section 14.10 Percent Dissociation in Solutions of Weak Acids
80) Which of the following are weak diprotic acids?A) carbonic acid - H2CO3, hydrosulfuric acid - H2S, acetic acid - CH3CO2HB) formic acid - HCO2H, acetic acid CH3CO2H, benzoic acid C6H5CO2HC) carbonic acid - H2CO3, oxalic acid - H2C2O4, sulfurous acid - H2SO3D) hydrocyanic acid - HCN, sulfuric acid - H2SO4, phosphoric acid - H3PO4Answer: CDiff: 2Topic: Section 14.11 Equilibria in Solutions of Polyprotic Acids
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81) What is the second stepwise equilibrium constant expression for phosphoric acid H3PO4?
A) Ka2 = ([H3O+][H2PO4-])/([H3PO4])
B) Ka2 = ([H3O+]2[HPO42-])/([H3PO4])
C) Ka2 = ([H3O+]3[PO43-])/([H3PO4])
D) Ka2 = ([H3O+][HPO42-])/([H2PO4-])Answer: DDiff: 2Topic: Section 14.11 Equilibria in Solutions of Polyprotic Acids
82) Calculate the pH of a 0.020 M carbonic acid solution, H2CO3(aq), that has the stepwise
dissociation constants and A) 1.70B) 4.03C) 6.37D) 10.25Answer: BDiff: 3Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
83) Calculate the pH of a 0.20 M H2SO3 solution that has the stepwise dissociation constants
Ka1 = 1.5 × 10-2 and Ka2 = 6.3 × 10-8.A) 1.26B) 1.32C) 1.82D) 2.52Answer: ADiff: 3Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
84) Calculate the concentration of bicarbonate ion, HCO3-, in a 0.010 M H2CO3 solution that
has the stepwise dissociation constants and
A) 6.6 × 10-5 MB) 4.3 × 10-7 MC) 4.3 × 10-9 MD) 5.6 × 10-11 MAnswer: ADiff: 3Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
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85) What is the pH of a 0.10 M H2Se solution that has the stepwise dissociation constants Ka1 =
1.3 × 10-4 and Ka2 = 1.0 × 10-11? A) 2.44B) 3.89C) 4.89D) 5.50Answer: ADiff: 3Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
86) What is the selenide ion concentration [Se2-] for a 0.100 M H2Se solution that has the
stepwise dissociation constants of Ka1 = 1.3 × 10-4 and Ka2 = 1.0 × 10-11?
A) 3.6 × 10-3 MB) 1.3 × 10-4 MC) 1.3 × 10-5 MD) 1.0 × 10-11 MAnswer: DDiff: 3Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
87) Which of the following can be classified as a weak base?A) CH3NH2B) NH2OHC) Both CH3NH2 and NH2OHD) Neither CH3NH2 nor NH2OHAnswer: CDiff: 2Topic: Section 14.12 Equilibria in Solutions of Weak Bases
88) What is the pH of a 0.100 M NH3 solution that has Kb = 1.8 × 10-5 ? The equation for the dissociation of NH3 is
A) 1.87B) 2.87C) 11.13D) 12.13Answer: CDiff: 3Topic: Section 14.12 Equilibria in Solutions of Weak BasesAlgo. Option: algorithmic
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89) What is the concentration of N in a 0.20 M ammonia solution? The base dissociaton constant for ammonia is 1.8 × .A) 0.0019 MB) 0.20 MC) 0.020 MD) 0.040 MAnswer: ADiff: 3Topic: Section 14.12 Equilibria in Solutions of Weak Bases
90) The concentration of C N in a 0.20 M methylamine (C ) solution is 2.32 × M. What is for methylamine?A) 2.7 × B) 5.4 × C) 1.2 ×D) 3.3 × Answer: ADiff: 3Topic: Section 14.12 Equilibria in Solutions of Weak Bases
91) What is the pH of a 0.30 M pyridine solution that has a Kb = 1.9 × 10-9 ? The equation for the dissociation of pyridine is
A) 4.62B) 8.72C) 9.38D) 10.38Answer: CDiff: 4Topic: Section 14.12 Equilibria in Solutions of Weak BasesAlgo. Option: algorithmic
92) Aniline, (C6H5NH2, Kb = 4.3 × 10-10 at 25°C) is an industrially important amine used in the making of dyes. Determine the pH of an aniline solution made by dissolving 3.90 g of aniline in enough water to make 100 mL of solution. A) 4.87B) 9.13C) 9.74D) 10.74Answer: BDiff: 4Topic: Section 14.12 Equilibria in Solutions of Weak BasesAlgo. Option: algorithmic
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93) Determine the ammonia concentration of an aqueous solution that has a pH of 11.50. The equation for the dissociation of NH3 (Kb = 1.8 × 10-5) is
A) 2.5 MB) 0.55 MC) 5.7 × 10-3 MD) 3.2 × 10-3 MAnswer: BDiff: 4Topic: Section 14.12 Equilibria in Solutions of Weak BasesAlgo. Option: algorithmic
94) How many grams of pyridine are there in 100 mL of an aqueous solution that has a pH of 9.00? The Kb for pyridine is 1.9 × and the equation of interest is
C5H5N(aq) + H2O(l) C⇌ 5H5NH+(aq) + OH-(aq).A) 0.053 gB) 0.42 gC) 0.79 gD) 7.9 gAnswer: BDiff: 4Topic: Section 14.12 Equilibria in Solutions of Weak Bases
95) What is the relationship between Ka and Kb at 25°C for a conjugate acid base pair?
A) Ka × Kb = 1 × 10-14
B) Ka/Kb = 1 × 10-14
C) Kb/Ka = 1 × 10-14
D) Ka + Kb = 1 × 10-14
Answer: ADiff: 1Topic: Section 14.13 Relation Between Ka and Kb
96) Ammonia NH3, has a base dissociation constant of 1.8 × 10-5. What is the conjugate acid of ammonia and what is its acid dissociation constant?A) NH4+, 1.9 × 109
B) NH4+, 1.8 × 10-5
C) NH4+, 5.6 × 10-10
D) NH2-, 5.6 × 10-10
Answer: CDiff: 2Topic: Section 14.13 Relation Between Ka and Kb
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97) Methylamine CH3NH2, has a base dissociation constant of 3.7 × 10-4. What is the conjugate acid of methylamine and what is its acid dissociation constant?A) CH3NH3+, 2.7 × 103
B) CH3NH3+, 3.7 × 10-4
C) CH3NH3+, 2.7 × 10-11
D) CH3NH2-, 2.7 × 10-11
Answer: CDiff: 2Topic: Section 14.13 Relation Between Ka and Kb
98) Acetic acid CH3COOH, has an acid dissociation constant of 1.8 × 10-5. What is the conjugate base of acetic acid and what is its base dissociation constant?A) CH3C(OH)2+, 5.6 × 104
B) CH3C(OH)2+, 5.6 × 10-10
C) CH3COOH, 5.6 × 10-10
D) CH3CO2-, 5.6 × 10-10
Answer: DDiff: 2Topic: Section 14.13 Relation Between Ka and Kb
99) Dihydrogen phosphate H2PO4-, has an acid dissociation constant of What is the
conjugate base of H2PO4- and what is its base dissociation constant?
A) H3PO4, 1.6 × 106
B) H3PO4, 1.6 × 10-8
C) HPO42-, 1.6 × 106
D) HPO42-, 1.6 × 10-8
Answer: DDiff: 2Topic: Section 14.13 Relation Between Ka and Kb
100) Which of the following salts are acidic?A) LiCl, NaCl, KClB) NH4Cl, CuCl2, AlCl3 C) NaCH3CO2, KCH3CO2, RbCH3CO2D) NaCl, NH4Cl, Na2CO3Answer: BDiff: 3Topic: Section 14.14 Acid-Base Properties of Salts
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101) Which one of the following salts, when dissolved in water, produces the solution with the highest pH?A) NaHSO4B) LiClO4C) MgOD) CH3NH3IAnswer: CDiff: 3Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
102) If an equal number of moles of the weak acid HCN and the strong base KOH are added to water, is the resulting solution acidic, basic, or neutral?A) acidicB) basicC) neutralD) There is insufficient information provided to answer this question.Answer: BDiff: 2Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
103) Arrange the following 0.10 M aqueous solutions in order of increasing pH: NaOH, HBr, NaCH3CO2, KBr, NH4Br.A) HBr, KBr, NH4Br, NaCH3CO2, NaOHB) NaOH, NaCH3CO2, NH4Br, KBr, HBrC) NaOH, NaCH3CO2, KBr, NH4Br, HBrD) HBr, NH4Br, KBr, NaCH3CO2, NaOHAnswer: DDiff: 3Topic: Section 14.14 Acid-Base Properties of Salts
104) Which one of the following salts, when dissolved in water, produces the solution with the highest pH?A) KIB) KBrC) KClD) KFAnswer: DDiff: 3Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
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105) Which one of the following salts, when dissolved in water, produces the solution with a pH closest to 7.00?A) NH4ClB) BaOC) NaHSO4D) RbIAnswer: DDiff: 3Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
106) Calculate the pH of a 0.100 M NaCH3CO2 solution. Ka for acetic acid, CH3CO2H, is
A) 2.87B) 5.13C) 8.87D) 11.13Answer: CDiff: 5Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
107) Calculate the pH of a of 0.100 M KBrO solution. Ka for hypobromous acid, HBrO, is
A) 3.15B) 4.85C) 9.15D) 10.85Answer: DDiff: 5Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
108) Calculate the pH of a 0.100 M CH3NH3Cl solution. Kb for methylamine, CH3NH2, is
A) 2.22B) 5.78C) 8.22D) 11.78Answer: BDiff: 5Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
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109) Equal volumes of 0.10 M NH3 (Kb = 1.8 × 10-5) and 0.10 M HCN (Ka = 4.9 × 10-10) are mixed together. Will the resulting solution be acidic, basic, or neutral?A) acidicB) basicC) neutralD) insufficient information to solveAnswer: BDiff: 3Topic: Section 14.14 Acid-Base Properties of Salts
110) Which one of the following salts, when dissolved in water, produces the solution with the lowest pH?A) NaClB) NH4ClC) MgCl2D) AlCl3Answer: DDiff: 3Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
111) What is the identity of M in the hydrate M(H2O)6n+ that has the 0.10 M solution with the lowest pH?A) Li+
B) Na+
C) Mg2+
D) Al3+Answer: DDiff: 3Topic: Section 14.14 Acid-Base Properties of Salts
112) What is the identity of M in the hydrate M(H2O)6n+ that has the 0.10 M solution with the highest pH?A) Li+
B) Na+
C) Mg2+
D) Al3+Answer: BDiff: 3Topic: Section 14.14 Acid-Base Properties of Salts
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113) What is the strongest acid among the following?A) HFB) HClC) HBrD) HIAnswer: DDiff: 2Topic: Section 14.3 Factors That Affect Acid Strength
114) What is the strongest acid among the following?A) H2OB) H2SC) H2SeD) H2TeAnswer: DDiff: 2Topic: Section 14.3 Factors That Affect Acid Strength
115) What is the strongest acid among the following?A) HFB) HClC) H2OD) H2SAnswer: BDiff: 2Topic: Section 14.3 Factors That Affect Acid Strength
116) What is the weakest acid among the following?A) SiH4B) PH3C) H2SD) HClAnswer: ADiff: 2Topic: Section 14.3 Factors That Affect Acid Strength
117) Which acid of the following set has the strongest conjugate base?A) CH4B) NH3C) H2OD) HFAnswer: ADiff: 3Topic: Section 14.3 Factors That Affect Acid Strength
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118) What is the strongest base among the following?A) ClO-
B) ClO2-
C) ClO3-
D) ClO4-
Answer: ADiff: 3Topic: Section 14.3 Factors That Affect Acid Strength
119) What is the strongest acid among the following?A) H2SO3B) H2SO4C) H2SeO3D) H2SeO4Answer: BDiff: 3Topic: Section 14.3 Factors That Affect Acid Strength
120) What is the strongest acid of the following?A) HOIB) HOBrC) HOClD) All are equivalent.Answer: CDiff: 2Topic: Section 14.3 Factors That Affect Acid Strength
121) What is the strongest acid among the following?A) HIOB) HIO2C) HIO3D) HIO4Answer: DDiff: 2Topic: Section 14.3 Factors That Affect Acid Strength
122) What is the strongest acid among the following?A) CH3CO2HB) ClCH2CO2HC) Cl2CHCO2HD) Cl3CCO2HAnswer: DDiff: 3Topic: Section 14.3 Factors That Affect Acid Strength
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123) Identify the Lewis acid that acts as a reactant in the following reaction Fe(H2O)63+(aq) + 6 CN-(aq) → Fe(CN)63-(aq) + 6 H2O(l).
A) Fe3+B) H2O
C) CN-
D) Fe(H2O)63+
Answer: ADiff: 3Topic: Section 14.15 Lewis Acids and Bases
124) Identify the Lewis acid that acts as a reactant in the following reactionCo(H2O)63+(aq) + 6 NH3(aq) → Co(NH3)63+(aq) + 6 H2O(l).
A) Co(H2O)63+
B) Co3+C) NH3D) H2OAnswer: BDiff: 3Topic: Section 14.15 Lewis Acids and Bases
125) For Cu2+ and CO2, which will behave as a Lewis acid toward OH- in water?
A) only Cu2+B) only CO2C) Cu2+ and CO2D) neither Cu2+ nor CO2Answer: CDiff: 3Topic: Section 14.15 Lewis Acids and Bases
126) Which one of the following is not considered to be a Lewis base?A) H2OB) NH3C) NH4+
D) Cl-Answer: CDiff: 3Topic: Section 14.15 Lewis Acids and Bases
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127) Which one of the following is least able to behave as a Lewis base?A) CH3NH2B) (CH3)2NHC) (CH3)3N
D) (CH3)3NH+
Answer: DDiff: 3Topic: Section 14.15 Lewis Acids and Bases
128) The compound BF3 can be described as a(n)A) Arrhenius acid.B) Brønsted-Lowry acid.C) Lewis acid.D) Lewis base.Answer: CDiff: 3Topic: Section 14.15 Lewis Acids and Bases
129) Identify the set of Lewis acids.A) BH3, BF3, Cu2+, CO2B) Cl-, OH-, NH3, H2O
C) H3PO4, H2PO4-, HPO42-, PO43-
D) CH3-, NH2-, OH-, F-
Answer: ADiff: 3Topic: Section 14.15 Lewis Acids and Bases
130) Which one of the following is expected to be the strongest Lewis acid?A) FeB) Fe+
C) Fe2+
D) Fe3+Answer: DDiff: 3Topic: Section 14.15 Lewis Acids and Bases
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In the following reaction the unshaded spheres represent H atoms.
131) Identify the Brønsted-Lowry acids.A) (1) and (3)B) (1) C) (2) and (3)D) (2) and (4)Answer: BDiff: 2Topic: Conceptual Problems
132) Identify the Brønsted-Lowry bases.A) (1) and (3)B) (1) and (4)C) (2) D) (2) and (4)Answer: CDiff: 2Topic: Conceptual Problems
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In the following reaction the unshaded spheres represent H atoms.
133) Identify the Brønsted-Lowry acids.A) (1) and (3)B) (1) and (4)C) (2) D) (2) and (4)Answer: CDiff: 2Topic: Conceptual Problems
134) Identify the Brønsted-Lowry bases.A) (1) and (3)B) (1) C) (2) and (3)D) (2) and (4)Answer: BDiff: 2Topic: Conceptual Problems
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In the following reaction the unshaded spheres represent H atoms.
135) Identify the Brønsted-Lowry acid/base conjugate pairs.A) (1)/(2) and (3)/(4)B) (1)/(3) and (2)/(4)C) (1)/(4) and (2)/(3)Answer: BDiff: 2Topic: Conceptual Problems
In the following reaction the unshaded spheres represent H atoms.
136) Identify the Brønsted-Lowry acid/base conjugate pairs.A) (1)/(2) and (3)/(4)B) (1)/(3) and (2)/(4)C) (1)/(4) and (2)/(3)Answer: BDiff: 2Topic: Conceptual Problems
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The following pictures represent aqueous solutions of three acids HA (A = X, Y, or Z); water molecules have been omitted for clarity.
137) Arrange the three acids in order of increasing acid strength.A) HZ < HY < HXB) HY < HZ < HXC) HZ < HX < HYD) HX < HZ < HYAnswer: DDiff: 2Topic: Conceptual Problems
138) Which acid, if any, is a strong acid?A) All are strong acids.B) HX and HZC) HYD) None are strong acids.Answer: CDiff: 2Topic: Conceptual Problems
139) Which acid has the smallest value of Ka?A) HXB) HYC) HZD) All have the same Ka value.Answer: ADiff: 2
38Copyright © 2014 Pearson Education, Inc.
Topic: Conceptual Problems
140) Which acid has the lowest percent dissociation?A) HXB) HYC) HZD) All have the same percent dissociation.Answer: ADiff: 2Topic: Conceptual Problems
141) Which acid solution has the lowest pH?A) HXB) HYC) HZD) All have the same pH.Answer: BDiff: 2Topic: Conceptual Problems
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142) Which of the above pictures represents a solution of a weak diprotic acid H2A for which (Water molecules have been omitted for clarity.)
A) picture (a)B) picture (b)C) picture (c)D) picture (d)Answer: CDiff: 3Topic: Conceptual Problems
143) Which of the above pictures represents a solution of a diprotic acid H2A for which and Ka2 is exceptionally small. (Water molecules have been omitted for clarity.)A) picture (a)B) picture (b)C) picture (c)D) picture (d)Answer: BDiff: 3Topic: Conceptual Problems
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The following pictures represent equal volumes of aqueous solutions of three acids HA (A = X, Y, or Z); water molecules have been omitted for clarity.
144) Arrange the acids in order of increasing acid strength.A) HZ < HY < HXB) HY < HZ < HXC) HZ < HX < HYD) HX < HZ < HYAnswer: BDiff: 2Topic: Conceptual Problems
145) Arrange the acids in order of increasing value of Ka.A) Ka(HZ) < Ka(HY) < Ka(HX)B) Ka(HY) < Ka(HZ) < Ka(HX)C) Ka(HZ) < Ka(HX) < Ka(HY)D) Ka(HX) < Ka(HZ) < Ka(HY)Answer: BDiff: 2Topic: Conceptual Problems
146) Arrange the acids in order of increasing value of percent dissociation.A) HZ < HY < HXB) HY < HZ < HXC) HZ < HX < HYD) HX < HZ < HYAnswer: BDiff: 2Topic: Conceptual Problems
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147) Arrange the acids in order of increasing pH.A) HZ < HY < HXB) HY < HZ < HXC) HZ < HX < HYD) HX < HZ < HYAnswer: DDiff: 2Topic: Conceptual Problems
148) Arrange the conjugate bases (A- = X-, Y-, or Z-) in order of increasing base strength.A) Z- < Y- < X-
B) Y- < Z- < X-
C) Z- < X- < Y-
D) X- < Z- < Y-Answer: DDiff: 3Topic: Conceptual Problems
149) Arrange the conjugate bases (A- = X-, Y-, or Z-) in order of increasing value of Kb.
A) Kb(Z-) < Kb(Y-) < Kb(X-)
B) Kb(Y-) < Kb(Z-) < Kb(X-)
C) Kb(Z-) < Kb(X-) < Kb(Y-)
D) Kb(X-) < Kb(Z-) < Kb(Y-)Answer: DDiff: 3Topic: Conceptual Problems
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150) The following pictures represent solutions of three salts NaA (A- = X-, Y-, or Z-); water molecules and Na+ ions have been omitted for clarity. Arrange the three A- ions in order of decreasing base strength.
A) X- > Y- > Z-
B) X- > Z- > Y-
C) Y- > Z- > X-
D) Z- > Y- > XZ-Answer: BDiff: 2Topic: Conceptual Problems
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The following pictures represent solutions of three salts MA; water molecules have been omitted for clarity. Dotted spheres represent Ay- ions; gray spheres represent Mx+ ions; black spheres represent oxygen atoms; and unshaded spheres represent hydrogen atoms.
151) Which picture represents an acidic salt?A) (1)B) (2)C) (3)D) none of the aboveAnswer: BDiff: 3Topic: Conceptual Problems
152) Which picture represents a neutral salt?A) (1)B) (2)C) (3)D) none of the aboveAnswer: CDiff: 3Topic: Conceptual Problems
153) Which picture represents a basic salt?A) (1)B) (2)C) (3)D) none of the aboveAnswer: ADiff: 3Topic: Conceptual Problems
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154) Of the elements indicated on the periodic table shown above, which forms the strongest binary acid, H2X or HX, where A) AB) BC) CD) DAnswer: DDiff: 3Topic: Conceptual Problems
155) Of the elements indicated on the periodic table shown above, which forms the weakest binary acid, H2X or HX, where A) AB) BC) CD) DAnswer: ADiff: 3Topic: Conceptual Problems
156) Of the elements indicated on the periodic table shown above, which forms the strongest oxoacid acid with the formula H2XO3 or HXO3, where A) AB) BC) CD) DAnswer: BDiff: 3Topic: Conceptual Problems
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157) Of the elements indicated on the periodic table shown above, which forms the weakest oxoacid acid with the formula H2XO3 or HXO3, where A) AB) BC) CD) DAnswer: CDiff: 3Topic: Conceptual Problems
158) SO3 reacts with H2O to form H2SO4. Which picture below correctly represents the curved arrow notation for the initial Lewis acid-Lewis base interaction in this reaction; what is the Lewis acid and the Lewis base?
A) Picture (1) is correct; H2O is the Lewis acid and SO3 is the Lewis base.B) Picture (1) is correct; SO3 is the Lewis acid and H2O is the Lewis base.C) Picture (2) is correct; H2O is the Lewis acid and SO3 is the Lewis base.D) Picture (2) is correct; SO3 is the Lewis acid and H2O is the Lewis base.Answer: DDiff: 4Topic: Conceptual Problems
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159) CO2 reacts with H2O to form HCO3- and H+. Which picture below correctly represents the curved arrow notation for the initial Lewis acid-Lewis base interaction in this reaction; what is the Lewis acid and the Lewis base?
(1) (2)
A) Picture (1) is correct; H2O is the Lewis acid and CO2 is the Lewis base.B) Picture (1) is correct; CO2 is the Lewis acid and H2O is the Lewis base.C) Picture (2) is correct; H2O is the Lewis acid and CO2 is the Lewis base.D) Picture (2) is correct; CO2 is the Lewis acid and H2O is the Lewis base.Answer: BDiff: 4Topic: Conceptual Problems
160) BF3 and NH3 undergo a Lewis acid-base reaction forming an adduct. Which picture below correctly represents the curved arrow notation for the initial Lewis acid-Lewis base interaction in this reaction; what is the Lewis acid and the Lewis base?
A) Picture (1) is correct; NH3 is the Lewis acid and BF3 is the Lewis base.B) Picture (2) is correct; BF3 is the Lewis acid and NH3 is the Lewis base.C) Picture (3) is correct; NH3 is the Lewis acid and BF3 is the Lewis base.D) Picture (4) is correct; BF3 is the Lewis acid and NH3 is the Lewis base.Answer: BDiff: 4Topic: Conceptual Problems
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14.2 Algorithmic Questions
1) When dissolved in water, which compound is generally considered to be an Arrhenius acid? A) H NO2 B) KOHC) Li F D) CH3OH Answer: ADiff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry TheoryAlgo. Option: algorithmic
2) Calculate the hydronium ion concentration in an aqueous solution that contains 2.50 × 10-6 M in hydroxide ion.A) 4.00 × 10-7 MB) 4.00 × 10-8 MC) 4.00 × 10-9 MD) 5.00 × 10-9 MAnswer: CDiff: 2Topic: Section 14.4 Dissociation of WaterAlgo. Option: algorithmic
3) Calculate the hydroxide ion concentration in an aqueous solution that contains 3.50 × 10-4 M in hydronium ion.A) 2.86 × 10-3 MB) 2.86 × 10-10 MC) 2.86 × 10-11 MD) 3.50 × 10-11 MAnswer: CDiff: 2Topic: Section 14.4 Dissociation of WaterAlgo. Option: algorithmic
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4) A solution with a hydrogen ion concentration of 3.25 × 10-6 M is ________ and has a hydroxide ion concentration of ________. A) acidic, 3.08 × 10-8 MB) acidic, 3.08 × 10-9 MC) basic, 3.08 × 10-8 MD) basic, 3.08 × 10-9 MAnswer: BDiff: 2Topic: Section 14.4 Dissociation of WaterAlgo. Option: algorithmic
5) A solution with a hydroxide ion concentration of 4.15 × 10-6 M is ________ and has a hydrogen ion concentration of ________. A) acidic, 2.41 × 10-8 MB) acidic, 2.41 × 10-9 MC) basic, 2.41 × 10-8 MD) basic, 2.41 × 10-9 MAnswer: DDiff: 2Topic: Section 14.4 Dissociation of WaterAlgo. Option: algorithmic
6) Calculate the pH for an aqueous solution of acetic acid that contains hydronium ion. A) 4.65 × 10-12 MB) 2.15 × 10-3 MC) 2.67D) 11.33Answer: CDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
7) Calculate the pH for an aqueous solution of pyridine that contains hydroxide ion.A) 4.65 × 10-11
B) 2.15 × 10-4 C) 3.67D) 10.33Answer: DDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
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8) What is the hydroxide ion concentration and the pH for a hydrochloric acid solution that has a hydronium ion concentration of
A) 6.67 × 10-12 M, 2.82B) 6.67 × 10-12 M, 11.18C) 6.67 × 10-13 M, 1.82D) 6.67 × 10-13 M, 12.17Answer: CDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
9) What is the hydronium ion concentration and the pH for an aqueous solution of NH3 that has
a hydroxide ion concentration of
A) 4.44 × 10-12 M and 2.65B) 4.44 × 10-12 M and 11.35C) 4.44 × 10-13 M and 1.65D) 4.44 × 10-13 M and 12.35Answer: DDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
10) What is the hydronium ion concentration of an acid rain sample that has a pH of 3.45? A) 2.82 × 10-11 MB) 3.55 × 10-4 M C) 3.45 MD) 10.55 MAnswer: BDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
11) What is the hydroxide ion concentration of a lye solution that has a pH of 9.20? A) 6.31 × 10-10 MB) 1.58 × 10-5 MC) 4.80 M D) 9.20 MAnswer: BDiff: 2Topic: Section 14.5 The pH ScaleAlgo. Option: algorithmic
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12) What is the pH of a 0.020 M HClO4 solution?A) 0.020B) 0.040C) 1.70D) 12.30Answer: CDiff: 2Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
13) What is the pH of a 0.040 M Ba(OH)2 solution?A) 1.10B) 1.40C) 12.60D) 12.90Answer: DDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
14) What is the pH of a solution prepared by dissolving 0.45 grams of solid CaO (lime) in enough water to make 2.00 L of aqueous Ca(OH)2 (limewater)?
CaO(s) + H2O(l) → Ca2+(aq) + 2 OH-(aq)A) 2.10B) 2.40C) 11.60D) 11.90Answer: DDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
15) What is the pH of a solution prepared by diluting 20.00 mL of 0.10 M HCl with enough water to produce a total volume of 100.00 mL?A) 1.00B) 1.70C) 2.00D) 3.40Answer: BDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
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16) What is the pH of a solution prepared by diluting 100.00 mL of 0.020 M Ba(OH)2 with enough water to produce a total volume of 250.00 mL?A) 1.80B) 2.10C) 11.90D) 12.20Answer: DDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
17) What is the pH of a solution prepared by mixing 100.00 mL of 0.20 M HCl with 150.00 mL of 0.10 M HCl? Assume that the volumes are additive. A) 0.17B) 0.52C) 0.85D) 1.70Answer: CDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
18) What is the pH of a solution prepared by mixing 100.00 mL of 0.020 M Ca(OH)2 with 50.00 mL of 0.300 M NaOH? Assume that the volumes are additive.A) 13.05B) 13.10C) 13.28D) 13.58Answer: BDiff: 3Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong BasesAlgo. Option: algorithmic
19) What is the hydronium ion concentration of a 0.500 M acetic acid solution with Ka = 1.8 ×
10-5? The equation for the dissociation of acetic acid is:CH3CO2H(aq) + H2O(l) ⇌ H3O+(aq) + CH3CO2-(aq).
A) 3.0 × 10-2 MB) 4.2 × 10-2 MC) 3.0 × 10-3 MD) 4.2 × 10-3 MAnswer: CDiff: 3Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak AcidsAlgo. Option: algorithmic
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20) What is the hydronium ion concentration of a 0.150 M hypochlorous acid solution with The equation for the dissociation of hypochlorous acid is:
HOCl(aq) + H2O(l) ⇌ H3O+(aq) + OCl-(aq).
A) 1.9 × 10-4 MB) 7.2 × 10-4 MC) 2.8 × 10-5 MD) 7.2 × 10-5 MAnswer: DDiff: 3Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak AcidsAlgo. Option: algorithmic
21) Potassium hydrogen phthalate (molar mass = 204.2 g/mol)is one of the most commonly used acids for standardizing solutions containing bases. KHP is a monoprotic weak acid with
Calculate the pH of the solution that results when 0.50 g of KHP is dissolved in enough water to produce 25.0 mL of solution. A) 2.05B) 3.21C) 4.40D) 5.41Answer: BDiff: 4Topic: Section 14.9 Calculating Equilibrium Concentrations in Solutions of Weak AcidsAlgo. Option: algorithmic
22) Calculate the pH of a 0.080 M carbonic acid solution, H2CO3(aq), that has the stepwise
dissociation constants Ka1 = 4.3 × 10-7 and Ka2 = 5.6 × 10-11. A) 1.10B) 3.73C) 6.37D) 10.25Answer: BDiff: 4Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
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23) Calculate the pH of a 0.60 M H2SO3, solution that has the stepwise dissociation constants
Ka1 = 1.5 × 10-2 and A) 1.02B) 1.06C) 1.82D) 2.04Answer: BDiff: 5Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
24) Calculate the concentration of bicarbonate ion, HCO3-, in a 0.010 M H2CO3 solution that
has the stepwise dissociation constants Ka1 = 4.3 × 10-7 and Ka2 = 5.6 × 10-11.
A) 6.6 × 10-5 MB) 4.3 × 10-7 MC) 4.3 × 10-9 MD) 5.6 × 10-11 MAnswer: ADiff: 4Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
25) What is the pH of a 0.40 M H2Se solution that has the stepwise dissociation constants Ka1 =
1.3 × 10-4 and A) 2.14B) 3.89C) 4.28D) 5.57Answer: ADiff: 3Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
26) What is the selenide ion concentration [Se2-] for a 0.100 M H2Se solution that has the
stepwise dissociation constants of and
A) 3.6 × 10-3 MB) 1.3 × 10-4 MC) 1.3 × 10-5 MD) 1.0 × 10-11 MAnswer: DDiff: 3Topic: Section 14.11 Equilibria in Solutions of Polyprotic AcidsAlgo. Option: algorithmic
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27) What is the pH of a 0.200 M NH3 solution that has Kb = 1.8 × 10-5? The equation for the dissociation of NH3 is
A) 2.02B) 2.72C) 11.98D) 11.28Answer: DDiff: 3Topic: Section 14.12 Equilibria in Solutions of Weak BasesAlgo. Option: algorithmic
28) What is the pH of a 0.30 M pyridine solution that has Kb = 1.9 × 10-9? The equation for the dissociation of pyridine is
A) 4.62B) 8.72C) 9.38D) 10.38Answer: CDiff: 4Topic: Section 14.12 Equilibria in Solutions of Weak BasesAlgo. Option: algorithmic
29) Aniline, (C6H5NH2, Kb = at 25°C) is an industrially important amine used in the making of dyes. Determine the pH of an aniline solution made by dissolving 6.90 g of aniline in enough water to make 100 mL of solution. A) 4.75B) 9.25C) 9.50D) 10.50Answer: BDiff: 4Topic: Section 14.12 Equilibria in Solutions of Weak BasesAlgo. Option: algorithmic
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30) Determine the ammonia concentration of an aqueous solution that has a pH of 11.00. The equation for the dissociation of NH3 (Kb = 1.8 × 10-5) is
A) 3.0 MB) 0.056 MC) 1.8 × 10-2 MD) 1.0 × 10-3 MAnswer: BDiff: 4Topic: Section 14.12 Equilibria in Solutions of Weak BasesAlgo. Option: algorithmic
31) Which one of the following salts, when dissolved in water, produces the solution with the highest pH? A) KHCO3B) CsClO4C) RaOD) CH3CH3NH3ClAnswer: CDiff: 3Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
32) If an equal number of moles of the weak acid HCN and the strong base KOH are added to water, is the resulting solution acidic, basic, or neutral? A) acidicB) basicC) neutralD) There is insufficient information provided to answer this question.Answer: BDiff: 2Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
33) Which one of the following salts, when dissolved in water, produces the solution with the highest pH?A) RbIB) RbBrC) RbClD) RbFAnswer: DDiff: 3Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
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34) Which one of the following salts, when dissolved in water, produces the solution with a pH closest to 7.00?A) NH4Br B) Ca OC) K HSO4D) CsIAnswer: DDiff: 3Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
35) Calculate the pH of a 0.800 M NaCH3CO2 solution. Ka for acetic acid, CH3CO2H, is
A) 2.42B) 4.68C) 9.32D) 11.58Answer: CDiff: 5Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
36) Calculate the pH of a 1.60 M KBrO solution. Ka for hypobromous acid, HBrO, is A) 2.55B) 4.25C) 9.75D) 11.45Answer: DDiff: 5Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
37) Calculate the pH of a 1.60 M CH3NH3Cl solution. Kb for methylamine, CH3NH2, is
A) 1.61B) 5.18C) 8.82D) 12.39Answer: BDiff: 5Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
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38) Which one of the following salts, when dissolved in water, produces the solution with the lowest pH?A) NaClB) KClC) MgCl2D) AlCl3Answer: DDiff: 3Topic: Section 14.14 Acid-Base Properties of SaltsAlgo. Option: algorithmic
14.3 Short Answer Questions
1) The Brønsted-Lowry acid in the chemical equation below is _________.HNO2(aq) + H2O(l) H⇌ 3O+(aq) + NO2–(aq)
Answer: HNO2Diff: 2Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
2) The equilibrium constant for the reaction below has the value Ka = 3.5 × 10–4. In this reaction the Brønsted-Lowry acid is ________.
HF(aq) + H2O(l) H⇌ 3O+(aq) + F–(aq)Answer: HFDiff: 2Topic: Section 14.2 Acid Strength and Base Strength
3) A proton hydrated by four water molecules has the formula ________.Answer: H9O4+
Diff: 3Topic: Section 14.1 Acid-Base Concepts: The Brønsted-Lowry Theory
4) An acidic solution with hydronium ion concentration [H+] = 1.60 × 10–3 M has a hydroxide ion concentration [OH–] = ________.Answer: 6.25 × 10–12 MDiff: 2Topic: Section 14.4 Dissociation of Water
5) At 50°C the value of Kw is 5.5 × 10–14, and the pH of a neutral solution at 50°C is ________.Answer: 6.63Diff: 3Topic: Section 14.5 The pH Scale
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6) The pH of a 0.025 M KOH solution is ________.Answer: 12.40Diff: 2Topic: Section 14.7 The pH in Solutions of Strong Acids and Strong Bases
7) The value of Ka for a 0.250 M HCN solution having a pH of 4.956 is ________.
Answer: 4.90 × 10–10Diff: 3Topic: Section 14.8 Equilibria in Solutions of Weak Acids
8) A 0.050 M solution of hydroxylamine, NH2OH, having Kb = 9.1 × 10–9 has a pH of ________.Answer: 9.33Diff: 4Topic: Section 14.12 Equilibria in Solutions of Weak Bases
9) A 0.10 M KNO2 solution will have a pH ________ seven.Answer: greater thanDiff: 2Topic: Section 14.14 Acid-Base Properties of Salts
10) The acid strength of an oxoacid having the general formula HnYOm increases as the electronegativity of Y ________ and as the oxidation number of Y ________.Answer: increases, increasesDiff: 3Topic: Section 14.3 Factors That Affect Acid Strength
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