Ionic equilibrium acids bases pH common ion effect hydrolysis and buffers - Question Bank

1. The dissociation constant of water (Kw) at 37°C is approximately 2.4 x 10^-14. What is the pH of neutral water at this temperature?
A) 7.0
B) 6.6
C) 7.3
D) 14.0
2. When a salt of a weak acid and strong base dissolves in water, the pH of the solution will be:
A) < 7
B) = 7
C) > 7
D) Depends on concentration
3. Which of the following is the most acidic?
A) pH = 7
B) pH = 5
C) pH = 2
D) pH = 9
4. The ionization of a weak acid is favored by:
A) Low concentration
B) High concentration
C) Addition of common ion
D) Addition of strong base
5. A buffer solution is made from a weak base and its conjugate acid. The Henderson-Hasselbalch equation for this buffer is:
A) pOH = pKb + log([conjugate acid]/[base])
B) pH = pKa + log([base]/[conjugate acid])
C) pOH = pKa + log([conjugate base]/[acid])
D) pH = pKb + log([conjugate base]/[base])
6. If the solubility of AgCl is 's', then its Ksp is:
A) s
B) 2s
C) s^2
D) 4s
7. Which of the following will decrease the pH of a solution?
A) Adding NaOH
B) Adding HCl
C) Adding NaCl
D) Adding water
8. The conjugate base of H2O is:
A) H3O+
B) OH-
C) O2-
D) H2O2
9. The pH of a 0.0001 M solution of NaOH is:
A) 1
B) 4
C) 10
D) 13
10. Which of the following statements is true for a neutral solution at 25°C?
A) [H+] > [OH-]
B) [H+] < [OH-]
C) [H+] = [OH-]
D) pH = 0
11. For a polyprotic acid, the first dissociation constant (Ka1) is generally:
A) Greater than Ka2
B) Less than Ka2
C) Equal to Ka2
D) Zero
12. The common ion effect is an application of:
A) Le Chatelier's principle
B) Hess's law
C) First law of thermodynamics
D) Law of conservation of mass
13. The buffer range of a buffer solution is typically:
A) pKa ± 1
B) pKa ± 2
C) pKa ± 0.5
D) pKa ± 0.1
14. Which type of hydrolysis occurs when a salt of a weak acid and strong base is dissolved in water?
A) Cationic hydrolysis
B) Anionic hydrolysis
C) Neutral hydrolysis
D) No hydrolysis
15. The pKa of a weak acid is 5. What is the Ka?
A) 5 x 10^-5
B) 10^-5
C) 10^5
D) 5 x 10^5
16. The pH of a 0.01 M solution of a monoprotic strong acid is:
A) 1
B) 2
C) 3
D) 13
17. Which of the following is a Lewis base?
A) BF3
B) AlCl3
C) CO2
D) NH3
18. If the solubility of a sparingly soluble salt M(OH)2 is 's', then its solubility product (Ksp) is:
A) 4s3
B) 27s4
C) s
D) s2
19. The Ostwald's dilution law is applicable to:
A) Strong electrolytes
B) Weak electrolytes
C) Non-electrolytes
D) All electrolytes
20. A buffer solution is prepared by mixing a weak acid with:
A) Its conjugate base
B) Its conjugate acid
C) A strong base
D) A strong acid
21. The hydrolysis of the salt of a strong acid and a strong base results in a solution that is:
A) Acidic
B) Basic
C) Neutral
D) Highly alkaline
22. Which of the following species is NOT a Brønsted-Lowry acid?
A) H3O+
B) CH3COOH
C) NH4+
D) Cl-
23. The pH of a 0.1 M solution of acetic acid (Ka = 1.8 x 10^-5) is approximately:
A) 2.87
B) 3.42
C) 4.15
D) 5.00
24. A substance that can act as both an acid and a base is called:
A) Amphipathic
B) Amphoteric
C) Anhydrous
D) Azeotrope
25. What is the relationship between pH and pOH at 25°C?
A) pH + pOH = 14
B) pH - pOH = 14
C) pH * pOH = 14
D) pH / pOH = 14
26. The solubility product (Ksp) of a sparingly soluble salt is the product of the concentrations of its ions, each raised to the power of its stoichiometric coefficient in the equilibrium equation. For CaF2, Ksp = [Ca2+][F-]^2. If [Ca2+] = x and [F-] = y, then Ksp is:
A) xy
B) x2y
C) xy2
D) x2y2
27. Which of the following is NOT a component of an acidic buffer solution?
A) A weak acid
B) Its conjugate base
C) A strong acid
D) A salt of the weak acid and strong base
28. Hydrolysis of a salt of a weak acid and weak base results in a solution that is:
A) Acidic
B) Basic
C) Neutral
D) Depends on the relative strengths of the acid and base
29. For a sparingly soluble salt like AgCl, the common ion effect leads to:
A) Increased solubility
B) Decreased solubility
C) No change in solubility
D) Increased dissociation
30. The degree of dissociation of a weak electrolyte increases with:
A) Increase in concentration
B) Decrease in concentration
C) Addition of a common ion
D) Addition of a strong acid
31. Which factor affects the pH of a buffer solution the most?
A) Dilution
B) Addition of a strong acid
C) Addition of a strong base
D) Addition of a salt of strong acid and strong base
32. The conjugate base of H2SO4 is:
A) HSO3-
B) SO42-
C) HSO4-
D) H3O+
33. A solution with a pH of 3 is considered:
A) Acidic
B) Basic
C) Neutral
D) Strongly basic
34. In the autoionization of water, the equilibrium constant Kw is equal to:
A) [H+][OH-]
B) [H+]/[OH-]
C) [OH-]/[H+]
D) [H+] + [OH-]
35. The buffer capacity of a buffer solution is highest when:
A) pH = pKa
B) pH > pKa
C) pH < pKa
D) pH = 7
36. Which of the following mixtures can act as a buffer solution?
A) CH3COOH and CH3COONa
B) HCl and NaCl
C) NaOH and NaCl
D) H2SO4 and Na2SO4
37. The salt of a weak acid and strong base, when dissolved in water, undergoes:
A) Cationic hydrolysis
B) Anionic hydrolysis
C) Neutralization
D) Dissociation only
38. For a weak base, a higher Kb value indicates:
A) Weaker base
B) Stronger base
C) Neutral character
D) Amphoteric nature
39. The dissociation constant of a weak acid (Ka) is a measure of its:
A) Strength
B) Concentration
C) Solubility
D) pH
40. What is the pOH of a 0.001 M solution of NaOH?
A) 1
B) 2
C) 11
D) 13
41. The pH of pure water at 25°C is:
A) 0
B) 7
C) 14
D) 1
42. Which of the following is a Lewis acid?
A) NH3
B) H2O
C) BF3
D) OH-
43. The Henderson-Hasselbalch equation for an acidic buffer is:
A) pH = pKa + log([conjugate base]/[acid])
B) pOH = pKb + log([conjugate acid]/[base])
C) pH = pKw + log([acid]/[conjugate base])
D) pOH = pKa + log([acid]/[base])
44. A buffer solution resists changes in pH upon addition of small amounts of:
A) Strong acid or strong base
B) Weak acid or weak base
C) Salt of strong acid and strong base
D) Water
45. Hydrolysis of a salt of a strong acid and weak base results in a solution that is:
A) Acidic
B) Basic
C) Neutral
D) Amphoteric
46. The common ion effect describes the decrease in the solubility of a sparingly soluble salt when:
A) A common ion is added to the solution.
B) The temperature of the solution is increased.
C) The volume of the solvent is decreased.
D) An acid is added to the solution.
47. Which of the following is an amphoteric substance?
A) HCl
B) NaOH
C) H2O
D) NaCl
48. The conjugate acid of NH3 is:
A) NH2-
B) NH4+
C) OH-
D) NH2OH
49. According to the Brønsted-Lowry theory, a base is a substance that:
A) Accepts a proton
B) Donates a proton
C) Accepts an electron pair
D) Donates an electron pair
50. What is the pH of a 0.01 M solution of HCl?
A) 1
B) 2
C) 7
D) 13