Competitive Exams: Chemistry MCQs (Practice-Test 17 of 31)

  1. Calculate the solubility (in M) of MgF2 (Ksp = 6.5 × 10 − 9) in water.

  2. Calculate the solubility (in M) of AgBr (Ksp = 5.0 × 10 − 15) in a solution that initially contains 0.25 M NaBr.

  3. Which of the following best describes what will happen when a solution of AgNO3 is slowly added to a saturated solution of silver acetate, CH3COOAg, without changing the volume significantly? CH3COOAg (s) ⇔ CH3COO- (aq) + Ag + (aq)

    1. Some of the solid silver acetate will dissolve.

    2. The concentration of acetate ion will increase.

    3. Some solid silver acetate will precipitate.

    4. The concentrations of acetate ion and silver ion will both increase.

    5. The addition of AgNO3 will have no effect on the position of the equilibrium.

  4. Which one of the following groups contains only salts that are expected to be soluble in water?

    1. ZnS, KNO3, CoS, PbCrO4

    2. NaCl, KNO3, Zn (NO3) 2, MgSO4

    3. Ca3 (PO4) 2, Cr (OH) 3, NaCl, ZnS

    4. AgOH, Cu (OH) 2, KCl, NaI

    5. A correct response is not given.

  5. Which of the following groups contains only salts that are expected to be highly soluble in water?

    1. NaCl, KNO3, ZnS, PbCrO4

    2. NaCl, KNO3, Zn (NO3) 2, Na2S.

    3. ZnS, PbCrO4, Ca3 (PO4) 2, Cr (OH) 3

    4. ZnS, KNO3, PbCrO4, CoS.

    5. A correct response is not given.

  6. Which of the following groups contains only salts that are expected to be slightly soluble or insoluble in water?

    1. NaCl, KNO3, ZnS, PbCrO4

    2. NaCl, KNO3, Zn (NO3) 2, Na2S.

    3. ZnS, PbCrO4, Ca3 (PO4) 2, Cr (OH) 3

    4. ZnS, KNO3, PbCrO4, CoS.

    5. A correct response is not given.

    Use the following reaction to answer the next four questions:

    Ca3 (PO4) 2 ⇔ 3 Ca2 + + 2 PO43-

  7. What is the correct expression for the solubility product constant for calcium phosphate?

    1. Ksp = [Ca2 + ] [PO43-]

    2. Ksp = [Ca2 + ]2 [PO43-]2

    3. Ksp = [Ca2 + ]2 [PO43-]2

    4. Ksp = [Ca2 + ]3 [PO43-]2

    5. The correct response is not given.

  8. What is the correct relationship between the solubility of calcium phosphate in pure water, C0 (Ca3 (PO4) 2), and the equilibrium concentration of calcium ion, [Ca2 + ]?

    1. [Ca2 + ] = 3C0 (Ca3 (PO4) 2)

    2. [Ca2 + ] = 2C0 (Ca3 (PO4) 2)

    3. [Ca2 + ] = (⅓) C0 (Ca3 (PO4) 2)

    4. [Ca2 + ] = (3/2) C0 (Ca3 (PO4) 2)

    5. The correct response is not given.

  9. Addition of calcium nitrate (Ca (NO3), 2), to a saturated solution of calcium phosphate would:

    1. have no effect on the solubility of calcium phosphate.

    2. cause the solubility of calcium phosphate to decrease.

    3. cause the solubility of calcium phosphate to increase.

    4. cause unpredictable changes in the solubility of calcium phosphate.

    5. The correct response is not given.

  10. Recognizing that the phosphate ion is a strong Bronsted base, we can accurately predict that addition of hydrochloric acid to a saturated solution of calcium phosphate would:

    1. have no effect on the solubility of calcium phosphate.

    2. cause the solubility of calcium phosphate to decrease.

    3. cause the solubility of calcium phosphate to increase.

    4. cause unpredictable changes in the solubility of calcium phosphate.

    5. The correct response is not given.

  11. The solubility of silver sulfate (Ag2SO4 ⇔ 2 Ag + + SO42-) in pure water is 0.0152 mol/L. Calculate the solubility product constant, Ksp, for silver sulfate.

  12. The solubility product constant for lead chloride (PbCl2 ⇔ Pb2 + + 2 Cl-) is Ksp = 1.6 × 10 − 5. Calculate the molar solubility of lead chloride in pure water.

  13. Calculate the molar solubility of gold chloride (AuCl3, Ksp = 3.2 × 10 − 25) in a solution containing 1.0 × 10 − 5 M chloride ion.

  14. Calculate the molar solubility of manganese hydroxide (Mn (OH) 2, Ksp = 2.0 × 10 − 13) in a solution buffered at pH = 9.00.

  15. What happens to the concentration of the Pb2 + and SO42-ions in a saturated solution of PbSO4 in contact with solid PbSO4 when the solution evaporates to half of its original volume?

    1. The concentrations of Pb2 + and SO42-increase.

    2. The concentrations of Pb2 + and SO42-decrease.

    3. The concentrations of Pb2 + and SO42-remain the same.

    4. It is impossible to say unless we know the Ksp of PbSO4.