Chemistry 12 — U4 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：19 道选择题（Multiple Choice Questions）
- 来源：StudyForge — Quiz 11434-152507 (U4 Exam)
- 答案位置：每题下方附 Answer
- 覆盖范围：Unit 4 — Solubility Equilibrium
Q1. In a saturated solution of KNO₃, the rate of crystallization is
(A) greater than the rate of dissolving. (B) equal to zero. (C) less than the rate of dissolving. (D) equal to the rate of dissolving.
Answer: (D)
Q2. Consider the following solutes:
I. K₃PO₄
II. C₂H₅OH
III. C₁₂H₂₂O₁₁
IV. KCH₃COO
Which of the solutes above form only molecular aqueous solutions?
(A) II and III (B) I and IV (C) I, II, III and IV (D) I and II (E) II, III and IV
Answer: (A)
Q3. A 200.0 mL solution contains 0.050 mol of Ba(NO₃)₂. The [NO₃⁻] is
(A) 0.50 M (B) 0.10 M (C) 0.050 M (D) 0.25 M (E) 0.12 M
Answer: (A)
Q4. When 250 mL of 0.24 M Na₂CO₃ are added to 850 mL of water, the resulting ion concentrations are
(A) [Na⁺] = 0.48 M and [CO₃²⁻] = 0.24 M (B) [Na⁺] = 0.11 M and [CO₃²⁻] = 0.055 M (C) [Na⁺] = 0.14 M and [CO₃²⁻] = 0.071 M (D) [Na⁺] = 0.071 M and [CO₃²⁻] = 0.071 M (E) [Na⁺] = 0.055 M and [CO₃²⁻] = 0.055 M
Answer: (B)
Q5. Identify the most soluble sulphide.
(A) PbS, Ksp = 7.0 × 10⁻²⁹ (B) MnS, Ksp = 2.3 × 10⁻¹³ (C) HgS, Ksp = 1.6 × 10⁻⁵⁴ (D) ZnS, Ksp = 1.7 × 10⁻¹⁰ (E) FeS, Ksp = 3.7 × 10⁻¹⁹
Answer: (D)
Q6. Which of the following substances has the lowest solubility?
(A) BaS (B) FeS (C) CuS (D) ZnS
Answer: (C)
Q7. When equal volumes of 0.20 M SrBr₂ and 0.20 M AgNO₃ are combined ...
(A) no precipitate forms. (B) a precipitate of SrAg forms. (C) precipitates of both AgBr and Sr(NO₃)₂ form. (D) a precipitate of only AgBr forms. (E) a precipitate of only Sr(NO₃)₂ forms.
Answer: (D)
Q8. When equal volumes of 0.2 M NH₄Cl and 0.2 M CuSO₄ are combined,
(A) a precipitate of both (NH₄)₂SO₄ and CuCl₂ forms. (B) a precipitate does not form. (C) a precipitate of CuCl₂ forms. (D) a precipitate of (NH₄)₂SO₄ forms.
Answer: (B)
Q9. Which one of the following equilibrium systems is described by a Ksp?
(A) Mg(OH)₂(s) ⇌ Mg²⁺(aq) + 2OH⁻(aq) (B) 2Mg(OH)₂(s) ⇌ 2MgO(s) + O₂(g) + 2H₂(g) (C) Mg²⁺(aq) + 2OH⁻(aq) ⇌ Mg(OH)₂(s) (D) Mg(OH)₂(aq) ⇌ Mg(s) + O₂(g) + H₂(g)
Answer: (A)
Q10. The Ksp expression for calcium hydroxide is
(A) Ksp = 1 / ([Ca²⁺][2OH⁻]²) (B) Ksp = [Ca²⁺][OH⁻]² (C) Ksp = [Ca²⁺][2OH⁻]² (D) Ksp = 1 / ([Ca²⁺][OH⁻]²)
Answer: (B)
Q11. A saturated solution of NiCO₃ was evaporated to dryness. A 250.0 mL sample was found to contain 1.1 × 10⁻² g NiCO₃. The molar mass of NiCO₃ is 118.7 g/mol. The molar solubility of NiCO₃ is
(A) 5.6 × 10⁻⁶ M (B) 3.7 × 10⁻⁴ M (C) 1.4 × 10⁻⁷ M (D) 9.3 × 10⁻⁵ M (E) 4.4 × 10⁻² M
Answer: (B)
Q12. The solubility of calcium oxalate is
(A) 5.3 × 10⁻¹⁸ M (B) 2.3 × 10⁻⁹ M (C) 4.8 × 10⁻⁵ M (D) 1.2 × 10⁻⁹ M
Answer: (C)
Q13. At a certain temperature, the solubility of BaF₂ is 7.4 × 10⁻³ moles per litre. The Ksp of BaF₂ at this temperature is
(A) 1.6 × 10⁻⁶ (B) 1.1 × 10⁻⁴ (C) 5.5 × 10⁻⁵ (D) 7.4 × 10⁻³
Answer: (A)
Q14. When equal volumes of 0.008 M Pb(NO₃)₂ and 0.008 M KCl are mixed,
(A) a precipitate does not form 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 forms because trial ion product < Ksp
Answer: (C)
Q15. A reagent that may be used to separate Cl⁻ from S²⁻ by precipitation is
(A) AgNO₃ (B) Pb(NO₃)₂ (C) Al(NO₃)₃ (D) Ca(NO₃)₂ (E) KNO₃
Answer: (C)
Q16. Which of the following causes a precipitate to form when Sr²⁺(aq) is added but not when Zn²⁺(aq) is added?
(A) NO₃⁻ (B) S²⁻ (C) SO₄²⁻ (D) CO₃²⁻ (E) Cl⁻
Answer: (C)
Q17. Silver chloride, AgCl, would be least soluble in?
(A) 1.0 M AgNO₃ (B) pure H₂O (C) 1.0 M NaNO₃ (D) 1.0 M HCl (E) 1.0 M ZnCl₂
Answer: (E)
Q18. Consider the following equilibrium:
BaSO₄(s) ⇌ Ba²⁺(aq) + SO₄²⁻(aq)
Adding which of the following will cause more solid BaSO₄ to form?
(A) Mg(NO₃)₂(s) (B) Na₂SO₄(s) (C) K₂CO₃(s) (D) CaCl₂(s)
Answer: (B)
Q19. At 25°C, the maximum [Ag⁺] that can exist in 0.510 M KCl is?
(A) 0.510 M (B) 1.3 × 10⁻⁵ M (C) 3.5 × 10⁻¹⁰ M (D) 1.8 × 10⁻¹⁰ M
Answer: (C)