Chapter 15: Acids and Bases
1. The hydronium ion and the hydroxide ion, in that order, are:
A) H3O+, OH+ B) OH-, H3O- C) OH-, H+ D) H3O+, OH- E) H3O-, OH-
2. Which of the following does not fit the definition of a Brønsted Acid?
A) H3PO4 B) H2PO4– C) H2O D) NH4+ E) CO2
3. Which of the following does not fit the definition of a Brønsted Base?
A) CO32– B) NH3 C) H2O D) NH4+ E) HCO3–
4. In the reaction HSO4–(aq) + OH–(aq)
pairs are
A) A
B) B C) C
D) D
SO42–(aq) + H2O(l), the conjugate acid-base
E) E
5. In the reaction: CH3COOH(aq) + NH2– (aq)
CH3COO– (aq) + NH3(aq), the
conjugate acid-base pairs are:
A) pair 1: CH3COOH and CH3COO– ; pair 2: NH2– and NH3
B) pair 1: CH3COOH and NH3; pair 2: NH2– and CH3COO–
C) pair 1: CH3COOH and NH2– ; pair 2: NH3 and CH3OO–
D) pair 1: CH3COOH and CH3COO– ; pair 2: NH4+ and NH3
E) pair 1: CH3COOH and CH3COO– ; pair 2: NH2– and NH3+
6. In the reaction: 2H2O(l)
H3O+(aq) + OH– (aq) the conjugate acid-base pairs are
A) pair 1: H2O and H2O; pair 2: H3O+ and OH–
B) pair 1: H3O+ and OH–; pair 2: H3O+ and H2O
C) pair 1: H3O+ and OH–; pair 2: OH– and H2O
D) pair 1: H2O and OH–; pair 2: H2O and H3O+
E) pair 1: H3O+ and HO–: pair 2: OH– and H3O+
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Chapter 15: Acids and Bases
7. Identify the conjugate base of HPO42–
A) H2O B) H2PO4– C) H3PO4 D) PO43– E) OH–
8. Identify the conjugate base of HSO4 –
A) OH– B) H2SO4 C) H2O D) H2SO3
E) SO42–
9. Identify the conjugate base of HCO3–
A) H2CO3 B) CO32– C) OH– D) CO2
E) CO
10. Identify the conjugate acid of SO42–
A) H2SO4 B) HSO4– C) H2SO3
D) H3O+ E) SO32–
11. Identify the conjugate acid of HCO3–
A) H2O B) CO32– C) H2CO3 D) CO2
E) H3O+
12. Identify the conjugate acid of CO32–
A) H2CO3 B) HCO3– C) H2O D) H3O+
E) CO2
13. Which of the following is not a conjugate acid-base pair?
A) H3PO4 and H2PO4–
D) HPO42– and PO43–
–
2–
B) H2PO4 and HPO4
E) H2O and H3O+
C) H3PO4 and HPO42–
14. Which of the following is not a conjugate acid-base pair?
A) H2O and OH–
D) HO2– and H2O2
+
B) H2O and H3O
E) O22– and HO2–
+
–
C) H3O and OH
27. Which of the following solutions is acidic?
A) [H3O+] = 7.0 x 10-7 M
D)
+
-10
B) [H3O ] = 1.5 x 10 M
E)
C) [H3O+] < 7.0 x 10-7 M
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[H3O+] > 7.0 x 10-7 M
[H3O+] = 1.0 x 10-14 M
Chapter 15: Acids and Bases
28. Which of the following solutions is acidic?
A) [OH-] = 1.0 x 10-7 M
D)
B) [OH-] > 1.0 x 10-7 M
E)
-10
C) [OH ] = 1.0 x 10 M
[H3O+] = 1.0 x 10-10 M
[H3O+] < 1.0 x 10-7 M
29. Which of the following solutions is basic?
A) [OH-] = 1.0 x 10-14 M
B) [OH-] = 1.0 x 10-7 M
C) [H3O+] = 1.0 x 10-14 M
D)
E)
[H3O+] > 1.0 x 10-7 M
[OH-] < 1.0 x 10-7 M
30. Which of the following solutions is basic?
A) [H3O+] = 1.0 x 10-10 M
B) [OH-] = 1.0 x 10-10 M
C) [H3O+] > 1.0 x 10-7 M
D)
E)
[OH-] < 1.0 x 10-10 M
[OH-] = 1.0 x 10-7 M
31. Calculate the pH of a carbonated beverage in which the hydrogen ion concentration is 3.4
× 10–4 M.
A) 2.34 B) 3.47 C) 6.01 D) 7.99 E) 10.53
33. Calculate the H+ ion concentration in lemon juice having a pH of 2.40.
A) 4.0 × 10–2 M B) 250 M C) 0.38 M D) 4.0 × 10–3 M E) 12 M
44. Calculate the hydrogen ion concentration in a solution of fruit juice having a pH of 4.25.
A) 1.0 × 10–14 M
D) 2.5 × 10–4 M
–5
B) 5.6 × 10 M
E) 5.6 × 10–4 M
C) 4.0 × 10–25 M
45. The pH of tomato juice is about 4.5. Calculate the concentration of hydrogen ions in this
juice.
A) 3 × 10–10 M B) 3 × 10–5 M C) 5 × 10–4 M D) 4 M E) 3 × 1010 M
46. Calculate the hydrogen ion concentration in a solution having a pH of 4.60.
A) 4.0 × 10–3 M
D) 2.5 × 10–5 M
–9
B) 4.0 × 10 M
E) 2.5 × 10–4 M
C) 4.0 × 10–10 M
47. Calculate the hydrogen ion concentration in a solution of iced tea with lemon having a
pH of 2.87.
A) 2.9 × 10–2 M
D) 2.9 × 10–3 M
–2
B) 5.7 × 10 M
E) 5.7 × 10–4 M
–3
C) 1.3 × 10 M
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Chapter 15: Acids and Bases
48. The pH of a Ba(OH)2 solution is 10.00. What is the H+ ion concentration of this
solution?
A) 4.0 × 10–11 M
D) 1.0 × 10–10 M
–10
B) 1.6 × 10 M
E) 10. M
C) 1.3 × 10–5 M
49. Diet cola drinks have a pH of about 3.0, while milk has a pH of about 7.0. How many
times greater is the H3O+ concentration in diet cola than in milk?
A) 2.3 times higher in diet cola than in milk
B) 400 times higher in diet cola than in milk
C) 0.43 times higher in diet cola than in milk
D) 1,000 times higher in diet cola than in milk
E) 10,000 times higher in diet cola than in milk
50. The pH of coffee is approximately 5.0. How many times greater is the [H3O+] in coffee
than in tap water having a pH of 8.0?
A) 0.62 B) 1.6 C) 30 D) 1,000 E) 1.0 × 104
51. The pH of coffee is approximately 5.0. How many times greater is the [H+] in coffee
than in neutral water?
A) 200 B) 100 C) 5.0 D) 1.4 E) 0.01
52. If the pH of an acid rain storm is approximately 3.0, how many times greater is the [H+]
in the rain than in a cup of coffee having a pH of 5.0?
A) 1000 B) 100 C) 20 D) 1.7 E) 0.60
57. What is the pH of a solution prepared by mixing 10.0 mL of a strong acid solution with
pH = 2.0 and 10.0 mL of a strong acid solution with pH = 6.0?
A) 2.0 B) 2.3 C) 4.0 D) 6.0 E) 8.0
58. The pOH of a solution is 9.60. Calculate the hydrogen ion concentration in this solution.
A) 2.5 × 10–10 M
D) 2.4 × 10–4 M
B) 6.0 × 10–9 M
E) 1.0 × 10–14 M
–5
C) 4.0 × 10 M
59. The pOH of a solution is 10.40. Calculate the hydrogen ion concentration in the solution.
A) 4.0 × 10–11 M
D) 2.5 × 10–4 M
B) 3.6 M
E) 1.8 × 10–4 M
C) 4.0 × 10–10 M
Ans: D Category: Medium Section: 15.3
60. Calculate the pOH for a solution with [H3O+] = 2.5 x 10-5 M
A) 4.60 B) 9.40 C) 4.0 x 10-10 D) 2.50 E) 11.50
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Chapter 15: Acids and Bases
61. Calculate the pOH for a solution with [H3O+] = 3.1 x 10-9 M
A) 3.10 B) 10.90 C) 8.51 D) 5.49 E) 3.2 x 10-6
146. Write the formula for the conjugate base of H3PO4
Ans: H2PO4–
147. Write the formula for the conjugate acid of HPO42–
Ans: H2PO4–
Category: Medium Section: 15.1
148. Write the formula for the conjugate acid of H2PO4–.
Ans: H3PO4
Category: Medium Section: 15.1
149. Write the formula for the conjugate base of H2PO4–.
Ans: HPO42–
Category: Medium Section: 15.1
152. Calculate the H+ ion concentration in a solution with a pH of 3.85.
Ans: 1.4 × 10–4 M
Category: Medium Section: 15.3
153. If the pH of stomach acid is 1.0, what is the hydroxide ion concentration in this solution?
Ans: 1 × 10–13 M
Category: Easy Section: 15.3
154. If the pH of liquid bleach is 12.0, what is the hydroxide ion concentration in this
solution?
Ans: 1 × 10–2 M
Category: Easy Section: 15.3
155. If the pH of pure water is 7.0, what is the hydroxide ion concentration in pure water?
Ans: 1 × 10–7 M
Category: Easy Section: 15.3
156. If the pH of tomato juice is 4.0, what is the hydroxide ion concentration in this solution?
Ans: 1 × 10–10 M
Category: Easy Section: 15.3
157. If the pH of seawater is 8.0, what is the hydroxide ion concentration in seawater?
Ans: 1 × 10–6 M
Category: Easy Section: 15.3
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Chapter 15: Acids and Bases
158. The pH of a sample of river water is 6.0. A sample of effluent from a food processing
plant has a pH of 4.0. What is the ratio of hydronium ion concentration in the effluent to
the hydronium ion concentration in the river?
Ans: The hydronium ion concentration in the effluent is 100 times greater than the
hydronium ion concentration in the river.
Category: Easy Section: 15.3
177. In aqueous solutions at 25°C, the sum of the ion concentrations ([H+] + [OH –]) equals 1
× 10 – 14.
Ans: False Category: Easy Section: 15.2
178. Kw = 1.0 x 10-14 at all temperatures
Ans: False Category: Easy Section: 15.2
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