Chemistry 12 — U4 Practice Exam MCQ¶
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创建日期: 2026-03-14 最后更新: 2026-03-16
使用说明¶
- 题目数量：21 道选择题（Multiple Choice Questions）
- 来源：StudyForge — Quiz 11431-152507 (U4 Practice Exam)
- 答案位置：每题下方附 Answer
- 覆盖范围：Unit 4 — Solubility Equilibrium
Q1. The equation that represents the equilibrium in a saturated solution of Fe₂(SO₄)₃ is
(A) Fe₂(SO₄)₃(s) ⇌ 3Fe³⁺(aq) + 2SO₄²⁻(aq) (B) Fe₂(SO₄)₃(s) ⇌ 2Fe³⁺(aq) + 3SO₄²⁻(aq) (C) Fe₂(SO₄)₃(s) ⇌ 3Fe²⁺(aq) + 2SO₄³⁻(aq) (D) Fe₂(SO₄)₃(s) ⇌ 2Fe²⁺(aq) + 3SO₄³⁻(aq)
Answer: (B)
Q2. A nitrate solution containing an unknown cation is added to each of the following three test tubes.
A precipitate forms in one test tube only. The unknown cation is
(A) Ag⁺ (B) Ca²⁺ (C) NH₄⁺ (D) Sr²⁺
Answer: (D)
Q3. The solubility product expression for a saturated solution of Fe₂(SO₄)₃ is
(A) Ksp = [Fe₂(SO₄)₃] / ([Fe³⁺]²[SO₄²⁻]³) (B) Ksp = [Fe³⁺]²[SO₄²⁻]³ (C) Ksp = [Fe³⁺]²[SO₄²⁻]³ / [Fe₂(SO₄)₃] (D) Ksp = [2Fe³⁺][3SO₄²⁻]
Answer: (B)
Q4. The solubility of magnesium carbonate is
(A) 6.8 × 10⁻⁶ M (B) 4.6 × 10⁻¹¹ M (C) 3.4 × 10⁻⁶ M (D) 2.6 × 10⁻³ M
Answer: (D)
Q5. At 25°C, the maximum [Zn²⁺] that can exist in 0.250 M Na₂S is?
(A) 8.0 × 10⁻²⁵ M (B) 2.0 × 10⁻²⁵ M (C) 5.0 × 10⁻²⁶ M (D) 4.5 × 10⁻¹³ M
Answer: (A)
Q6. Consider the following equilibrium:
AgCl(s) ⇌ Ag⁺(aq) + Cl⁻(aq)
Sodium chloride is added to a saturated solution of AgCl. The amount of solid AgCl will
(A) increase as the equilibrium shifts to the right. (B) decrease as the equilibrium shifts to the right. (C) increase as the equilibrium shifts to the left. (D) decrease as the equilibrium shifts to the left.
Answer: (C)
Q7. When 250 mL of 0.36 M Sr(OH)₂ are added to 750 mL of water, the resulting ion concentrations are
(A) [Sr²⁺] = 0.12 M and [OH⁻] = 0.12 M (B) [Sr²⁺] = 0.12 M and [OH⁻] = 0.24 M (C) [Sr²⁺] = 0.090 M and [OH⁻] = 0.090 M (D) [Sr²⁺] = 0.090 M and [OH⁻] = 0.180 M
Answer: (D)
Q8. Which of the following compounds could be used to prepare a 0.20 M solution of hydroxide ion?
(A) Zn(OH)₂ (B) KOH (C) Mg(OH)₂ (D) Fe(OH)₃
Answer: (B)
Q9. When equal volumes of 0.20 M K₂CrO₄ and 0.20 M AgNO₃ are mixed, a red precipitate is formed. The net ionic equation for this reaction is?
A. K⁺(aq) + NO₃⁻(aq) → KNO₃(s)
B. 2Ag⁺(aq) + CrO₄²⁻(aq) → Ag₂CrO₄(s)
C. K₂CrO₄(aq) + 2AgNO₃(aq) → Ag₂CrO₄(s) + 2KNO₃(aq)
D. 2Ag⁺(aq) + Cr₂O₇²⁻(aq) + 2K⁺(aq) + 2NO₃⁻(aq) → Ag₂Cr₂O₇(s) + 2KNO₃(aq)
The answer is equation
(A) A (B) C (C) B (D) D
Answer: (C)
即方程式 B：2Ag⁺(aq) + CrO₄²⁻(aq) → Ag₂CrO₄(s)
Q10. Which of the following could be used to separate Pb²⁺ from Ba²⁺ by precipitation?
(A) Na₂CO₃ (B) NaOH (C) Na₂S (D) Na₂SO₄
Answer: (C)
Q11. The molar solubility of iron(II) sulphide is
(A) 7.7 × 10⁻¹⁰ M (B) 3.6 × 10⁻³⁷ M (C) 3.0 × 10⁻¹⁹ M (D) 6.0 × 10⁻¹⁹ M
Answer: (A)
Q12. A solution of AgNO₃ is slowly added to a mixture containing 0.10 M Br⁻, Cl⁻, I⁻, and IO₃⁻. The precipitate which forms first is?
(A) AgBr (B) AgIO₃ (C) AgCl (D) AgI
Answer: (D)
Q13. When equal volumes of 0.1 M Pb(NO₃)₂ and 0.1 M KCl are mixed,
(A) a precipitate forms because trial ion product > Ksp (B) a precipitate forms because trial ion product < Ksp (C) a precipitate does not form because trial ion product > Ksp (D) a precipitate does not form because trial ion product < Ksp
Answer: (A)
Q14. Consider the following equilibrium:
AgCl(s) ⇌ Ag⁺(aq) + Cl⁻(aq)
When Br⁻(aq) is added to a saturated solution of AgCl,
(A) more AgCl dissolves and its solubility product increases. (B) more AgCl precipitates and its solubility product remains constant. (C) more AgCl dissolves and its solubility product remains constant. (D) more AgCl precipitates and its solubility product decreases.
Answer: (C)
Q15. Which of the following ions could be used to separate Cl⁻(aq) from SO₄²⁻(aq) by precipitation?
(A) Pb²⁺ (B) Ag⁺ (C) NH₄⁺ (D) Ca²⁺
Answer: (D)
Q16. Which of the following could be used to precipitate both Mg²⁺ and Ca²⁺ from hard water?
(A) ammonium chloride (B) sodium phosphate (C) potassium sulphide (D) lithium sulphate
Answer: (B)
Q17. The solubility of manganese(II) sulphide is 1.7 × 10⁻⁷ M at 25°C. The solubility product constant is
(A) 3.4 × 10⁻⁷ (B) 2.9 × 10⁻¹⁴ (C) 4.1 × 10⁻⁴ (D) 1.7 × 10⁻⁷
Answer: (B)
Q18. What is the maximum [Ag⁺] that can exist in 0.20 M NaBrO₃?
(A) 7.3 × 10⁻³ M (B) 2.7 × 10⁻⁴ M (C) 5.3 × 10⁻⁵ M (D) 1.1 × 10⁻⁵ M
Answer: (B)
Q19. Consider the following equilibrium:
CaCO₃(s) ⇌ Ca²⁺(aq) + CO₃²⁻(aq)
Which of the following reagents, when added to the equilibrium system, would cause more CaCO₃ to dissolve?
(A) H₂C₂O₄(s) (B) Na₂CO₃(s) (C) KNO₃(s) (D) CaCO₃(s)
Answer: (A)
Q20. In a saturated solution at equilibrium, the rate of dissolving is
(A) greater than the rate of crystallization. (B) less than the rate of crystallization. (C) equal to the rate of crystallization. (D) equal to zero.
Answer: (C)
Q21. Which of the following occurs when equal volumes of 0.02 M MgS and 0.02 M ZnSO₄ are mixed?
(A) A precipitate of MgSO₄ forms. (B) A precipitate does not form. (C) A precipitate of ZnS forms. (D) Precipitates of MgSO₄ and ZnS form.
Answer: (C)