CHEM 103 Module 7 Exam: Acids, Bases, pH, and Buffers 2026/2027
UPDATE Portage Learning
1. What is the Arrhenius definition of a base?
A. A substance that produces OH- ions in aqueous solution
B. A substance that produces H+ ions in aqueous solution
C. A substance that accepts a proton
D. A substance that donates an electron pair
Answer: A
Rationale: Arrhenius defined bases as substances that dissociate in water to produce
hydroxide (OH-) ions.
2. According to the Bronsted-Lowry theory, an acid is a:
A. Proton donor
B. Electron pair donor
C. Proton acceptor
D. Hydroxide ion producer
Answer: A
Rationale: The Bronsted-Lowry theory defines an acid as any species that can donate a
proton (H+ ion).
,3. What is the pH of a 0.01 M solution of HCl?
A. 1.0
B. 2.0
C. 7.0
D. 12.0
Answer: B
Rationale: HCl is a strong acid, so [H+] = 0.01 M. pH = -log(0.01) = 2.
4. Which of the following is the conjugate base of H2SO4?
A. HSO4-
B. H3SO4+
C. SO4^2-
D. OH-
Answer: A
Rationale: A conjugate base is formed by removing one proton (H+) from the acid.
Removing H+ from H2SO4 leaves HSO4-.
5. What is the sum of pH and pOH for any aqueous solution at 25 degrees
Celsius?
A. 14
B. 7
C. 10
D. 0
Answer: A
Rationale: The ion product constant of water (Kw) dictates that pH + pOH = 14 at 25
degrees Celsius.
, 6. Which substance is considered amphoteric?
A. HCl
B. H2O
C. NaOH
D. NaCl
Answer: B
Rationale: Amphoteric substances like water can act as either an acid (donating H+) or a
base (accepting H+).
7. What defines a Lewis acid?
A. An electron pair donor
B. An electron pair acceptor
C. A proton donor
D. A proton acceptor
Answer: B
Rationale: The Lewis definition focuses on electrons; an acid is an electron pair acceptor,
and a base is an electron pair donor.
8. Which of the following is a strong acid?
A. HF
B. CH3COOH
C. H3PO4
D. HNO3
Answer: D
Rationale: Nitric acid (HNO3) is one of the common strong acids that completely ionize in
solution.
UPDATE Portage Learning
1. What is the Arrhenius definition of a base?
A. A substance that produces OH- ions in aqueous solution
B. A substance that produces H+ ions in aqueous solution
C. A substance that accepts a proton
D. A substance that donates an electron pair
Answer: A
Rationale: Arrhenius defined bases as substances that dissociate in water to produce
hydroxide (OH-) ions.
2. According to the Bronsted-Lowry theory, an acid is a:
A. Proton donor
B. Electron pair donor
C. Proton acceptor
D. Hydroxide ion producer
Answer: A
Rationale: The Bronsted-Lowry theory defines an acid as any species that can donate a
proton (H+ ion).
,3. What is the pH of a 0.01 M solution of HCl?
A. 1.0
B. 2.0
C. 7.0
D. 12.0
Answer: B
Rationale: HCl is a strong acid, so [H+] = 0.01 M. pH = -log(0.01) = 2.
4. Which of the following is the conjugate base of H2SO4?
A. HSO4-
B. H3SO4+
C. SO4^2-
D. OH-
Answer: A
Rationale: A conjugate base is formed by removing one proton (H+) from the acid.
Removing H+ from H2SO4 leaves HSO4-.
5. What is the sum of pH and pOH for any aqueous solution at 25 degrees
Celsius?
A. 14
B. 7
C. 10
D. 0
Answer: A
Rationale: The ion product constant of water (Kw) dictates that pH + pOH = 14 at 25
degrees Celsius.
, 6. Which substance is considered amphoteric?
A. HCl
B. H2O
C. NaOH
D. NaCl
Answer: B
Rationale: Amphoteric substances like water can act as either an acid (donating H+) or a
base (accepting H+).
7. What defines a Lewis acid?
A. An electron pair donor
B. An electron pair acceptor
C. A proton donor
D. A proton acceptor
Answer: B
Rationale: The Lewis definition focuses on electrons; an acid is an electron pair acceptor,
and a base is an electron pair donor.
8. Which of the following is a strong acid?
A. HF
B. CH3COOH
C. H3PO4
D. HNO3
Answer: D
Rationale: Nitric acid (HNO3) is one of the common strong acids that completely ionize in
solution.
