Question 1

Fe(OH)3 is most soluble in which solution?

Accepted Answer

A)  0.2 M HCl 
B)  0.1 M KOH 
C)  pure water 
D)  0.1 M FeCl3 
E)  0.2 M CaCl2 
A)  0.2 M HCl 
B)  0.1 M KOH 
C)  pure water 
D)  0.1 M FeCl3 
E)  0.2 M CaCl2

Question 2

Which of the following soil additives would best reduce the concentration of dissolved Fe3+ in ground water?

Accepted Answer

A)  lime [Ca(OH)2] 
B)  saltpeter [KNO3] 
C)  ferric chloride [FeCl3] 
D)  ammonium nitrate 
E)  ammonium sulfate 
A)  lime [Ca(OH)2] 
B)  saltpeter [KNO3] 
C)  ferric chloride [FeCl3] 
D)  ammonium nitrate 
E)  ammonium sulfate

Question 3

A homeowner in Boston becomes concerned that there may be appreciable amounts of lead in her drinking water due to 150-year old water pipes in her house. Consequently, she takes a sample of her drinking water in to be analyzed. The laboratory technician, who is new on the job, has been told to analyze by precipitating the lead ion as the iodide (Ksp = 7.1 × 10-9 for PbI2) by slowly adding small portions of 1.00 M NaI solution. If we assume that the concentration of lead in the solution is 1.00 mg/liter or approximately 4.8 × 10-6 M (this would be 1.0 part per million) is it possible to detect the lead in the drinking water by adding a total of no more than 10.0 mL of NaI solution to a 100 mL sample of drinking water? You must of course consider dilution effects. What is Q?

Accepted Answer

A)  yes, Q = 4.0 × 10-7 
B)  yes, Q = 3.6 × 10-8 
C)  no, Q = 1.6 × 10-13 
D)  no, Q = 3.6 × 10-8 
E)  no, Q = 4.0 × 10-7 
A)  yes, Q = 4.0 × 10-7 
B)  yes, Q = 3.6 × 10-8 
C)  no, Q = 1.6 × 10-13 
D)  no, Q = 3.6 × 10-8 
E)  no, Q = 4.0 × 10-7

Question 4

When solid silver chloride is shaken with a 0.1 molar solution of potassium iodide, most of the silver chloride is converted to silver iodide. This transformation takes place because:

Accepted Answer

A)  silver iodide is less soluble than silver chloride 
B)  I- is a better reducing agent than Cl- 
C)  I- has a larger radius than Cl- 
D)  the Ksp of AgI is larger than the Ksp of AgCl 
E)  potassium chloride precipitates 
A)  silver iodide is less soluble than silver chloride 
B)  I- is a better reducing agent than Cl- 
C)  I- has a larger radius than Cl- 
D)  the Ksp of AgI is larger than the Ksp of AgCl 
E)  potassium chloride precipitates

Question 5

A solution contains [Ba2+] = 5.0 × 10-5 M, [Ag+] = 3.0 × 10-5 M, and [Zn2+] = 2.0 × 10-7 M. Sodium oxalate is slowly added so that [C2O42-] increases. 
Salt  BaC2O4     &emsp;&emsp;ZnC2O4     &emsp;&emsp;Ag2C2O4
Ksp 1.5 × 10-8  &emsp; 1.35 × 10-9   &emsp;1.1 × 10-11
Which one of the oxalates precipitates first?

Accepted Answer

A)  BaC2O4 
B)  Na2C2O4 
C)  ZnC2O4 
D)  Ag2C2O4 
E)  ZnC2O4 and Ag2C2O4 precipitate together 
A)  BaC2O4 
B)  Na2C2O4 
C)  ZnC2O4 
D)  Ag2C2O4 
E)  ZnC2O4 and Ag2C2O4 precipitate together

Question 6

If iron(III) acetate is added to be 1 × 10-10 M in a solution that is 0.10 M NH3, what is Qsp and will Fe(OH)3 precipitate? The Ksp of Fe(OH)3 is 4 × 10-38 and Kb for NH3 is 1.8 × 10-5.

Accepted Answer

A)  1.3 × 10-13, yes 
B)  1.7 × 10-16, yes 
C)  1.7 × 10-16, no 
D)  2.4 × 10-19, yes 
E)  2.4 × 10-19, no 
A)  1.3 × 10-13, yes 
B)  1.7 × 10-16, yes 
C)  1.7 × 10-16, no 
D)  2.4 × 10-19, yes 
E)  2.4 × 10-19, no

Question 7

Predict the molar solubility of the following salt in a solution that contains the given concentration of one of its ions: BaSO4; [SO42-] = 4.3 × 10-5 M; Ksp = 1.1 × 10-10

Accepted Answer

A)  4.7 × 10-15 M 
B)  6.9 × 10-8 M 
C)  8.0 × 10-4 M 
D)  2.6 × 10-6 M 
E)  1.6 × 10-3 M 
A)  4.7 × 10-15 M 
B)  6.9 × 10-8 M 
C)  8.0 × 10-4 M 
D)  2.6 × 10-6 M 
E)  1.6 × 10-3 M

Question 8

The solubility product constant of Mg(OH)2 is 9.0 × 10-12. If a solution is 0.010 M with respect to Mg2+ ion, the amount of [OH-] required to start the precipitation of Mg(OH)2 is:

Accepted Answer

A)  1.5 × 10-7 
B)  3.0 × 10-5 M 
C)  3.0 × 10-7 M 
D)  9.0 × 10-10 
E)  1.5 × 10-5 M 
A)  1.5 × 10-7 
B)  3.0 × 10-5 M 
C)  3.0 × 10-7 M 
D)  9.0 × 10-10 
E)  1.5 × 10-5 M

Question 9

In which of the following solutions will the concentration of dissolved silver species be the highest if solid AgNO3 is stirred with 1.00 L of solution?

Accepted Answer

A)  1.00 M NH3(aq) 
B)  1.00 M NaOH 
C)  1.00 M Na2SO4(aq) 
D)  1.00 M NaCl(aq) 
E)  1.00 M NaC2H3O2(aq) 
A)  1.00 M NH3(aq) 
B)  1.00 M NaOH 
C)  1.00 M Na2SO4(aq) 
D)  1.00 M NaCl(aq) 
E)  1.00 M NaC2H3O2(aq)

Question 10

The solubility of cerium iodate, Ce(IO3)3, molar mass = 664.83 g/mol, in pure water is 124 mg per 100 mL of water. Calculate the solubility product constant for cerium iodate.

Accepted Answer

A)  4.9 × 10-19 
B)  2.6 × 10-14 
C)  8.6 × 10-15 
D)  3.3 × 10-10 
E)  3.5 × 10-18 
A)  4.9 × 10-19 
B)  2.6 × 10-14 
C)  8.6 × 10-15 
D)  3.3 × 10-10 
E)  3.5 × 10-18

Question 11

Some solid in a solution at equilibrium means the solution is saturated.

Accepted Answer

A) True 
 B)False

Question 12

What is the composition of the precipitate formed when H2S gas is bubbled through 1.0 litre of a solution of 0.010 M Zn2+, 0.010 M Pb2+, and 0.010 M Mn2+, buffered at pH 2.0, until 0.10 mol of H2S has been added? [Ksp values are: ZnS: 1.6 × 10-23; MnS: 7.0 × 10-16; PbS: 7.0 × 10-29. For H2S, Ka1 = 1.0 × 10-7; Ka2 = 1.3 × 10-13.

Accepted Answer

A)  only ZnS 
B)  only MnS 
C)  only PbS 
D)  only MnS and PbS 
E)  only ZnS and PbS 
A)  only ZnS 
B)  only MnS 
C)  only PbS 
D)  only MnS and PbS 
E)  only ZnS and PbS

Question 13

Which of the following salts, each of which has a solubility product equal to 1.0 × 10-6, has the greatest molar solubility?

Accepted Answer

A)  MX 
B)  MX2 
C)  MX3 
D)  M2X 
A)  MX 
B)  MX2 
C)  MX3 
D)  M2X

Question 14

Write the solubility product constant expression for the following salt: PbC2O4.

Accepted Answer

A)  [Pb2+][C2O42-] 
B)  [Pb2+]2[C2O42-] 
C)  [Pb2+]2[C2O42-]2 
D)  [Pb2+][C2O42-]2 
E)  4[Pb2+][C2O42-] 
A)  [Pb2+][C2O42-] 
B)  [Pb2+]2[C2O42-] 
C)  [Pb2+]2[C2O42-]2 
D)  [Pb2+][C2O42-]2 
E)  4[Pb2+][C2O42-]

Question 15

When 200 mL of 0.10 M BaCl2 is added to 100 mL of 0.30 M Na2SO4, the number of moles of BaSO4 (solubility product = 1.1 × 10-10) precipitated is ________.

Accepted Answer

A)  0.020 mol 
B)  0.010 mol 
C)  0.20 mol 
D)  0.030 mol 
E)  0.10 mol 
A)  0.020 mol 
B)  0.010 mol 
C)  0.20 mol 
D)  0.030 mol 
E)  0.10 mol

Question 16

When equal volumes of the indicated solutions are mixed, precipitation should occur only for:     barium fluoride 1.0 × 10-6 calcium carbonate 2.8 × 10-9
Calcium fluoride 5.3 × 10-9
Magnesium fluoride 3.7 × 10-8
Silver carbonate 8.5 × 10-12

Accepted Answer

A)  2 × 10-5 M Ag+ + 2 × 10-5 M CO3 2- 
B)  2 × 10-5 M Ca2+ + 2 × 10-5 M CO3 2- 
C)  2 × 10-4 M Ca2+ + 2 × 10-2 M F- 
D)  2 × 10-5 M Mg2+ + 2 × 10-6 M F- 
E)  2 × 10-3 M Ba2+ + 2 × 10-3 M F- 
A)  2 × 10-5 M Ag+ + 2 × 10-5 M CO3 2- 
B)  2 × 10-5 M Ca2+ + 2 × 10-5 M CO3 2- 
C)  2 × 10-4 M Ca2+ + 2 × 10-2 M F- 
D)  2 × 10-5 M Mg2+ + 2 × 10-6 M F- 
E)  2 × 10-3 M Ba2+ + 2 × 10-3 M F-

Question 17

When equal volumes of the indicated solutions are mixed, precipitation should occur only for:     barium fluoride 1.0 × 10-6 calcium carbonate 2.8 × 10-9
Calcium fluoride 5.3 × 10-9
Magnesium fluoride 3.7 × 10-9
Silver carbonate 8.5 × 10-12

Accepted Answer

A)  2 × 10-5 M Ag+ + 2 × 10-5 M CO32- 
B)  2 × 10-4 M Ca2+ + 2 × 10-4 M CO32- 
C)  2 × 10-5 M Ca2+ + 2 × 10-3 M F- 
D)  2 × 10-5 M Mg2+ + 2 × 10-6 M F- 
E)  2 × 10-3 M Ba2+ + 2 × 10-3 M F- 
A)  2 × 10-5 M Ag+ + 2 × 10-5 M CO32- 
B)  2 × 10-4 M Ca2+ + 2 × 10-4 M CO32- 
C)  2 × 10-5 M Ca2+ + 2 × 10-3 M F- 
D)  2 × 10-5 M Mg2+ + 2 × 10-6 M F- 
E)  2 × 10-3 M Ba2+ + 2 × 10-3 M F-

Question 18

What ratio of [NH4+]/[NH3] would provide a buffer of pH low enough to avoid precipitation of Co(OH)2 [Ksp = 2.0 × 10-14] from a 0.50 M Co2+ solution? [Kb for NH3 = 1.8 × 10-5]

Accepted Answer

A)  1/50 
B)  1/90 
C)  1/1 
D)  90/1 
E)  50/1 
A)  1/50 
B)  1/90 
C)  1/1 
D)  90/1 
E)  50/1

Question 19

What is the concentration of Ca2+ in ppm (mg/L) in cave water saturated with calcite (calcium carbonate, Ksp = 4.7 × 10-9)?

Accepted Answer

A)  7.5 
B)  6.9 
C)  5.0 
D)  3.8 
E)  2.7 
A)  7.5 
B)  6.9 
C)  5.0 
D)  3.8 
E)  2.7

Question 20

What is the free Cu2+ concentration if 0.020 M Cu2+ solution is mixed with an equal volume of 4.0 M NH3? Kf for [Cu(NH3)4]2+ is 1.1 × 1013.

Accepted Answer

A)  5.7 × 10-15 
B)  2.8 × 10-16 
C)  6.2 × 10-17 
D)  4.5 × 10-15 
E)  1.7 × 10-16 
A)  5.7 × 10-15 
B)  2.8 × 10-16 
C)  6.2 × 10-17 
D)  4.5 × 10-15 
E)  1.7 × 10-16

Exam 18: Solubility and Complex-Ion Equilibria

Fe(OH)3 is most soluble in which solution?

Which of the following soil additives would best reduce the concentration of dissolved Fe3+ in ground water?

When solid silver chloride is shaken with a 0.1 molar solution of potassium iodide, most of the silver chloride is converted to silver iodide. This transformation takes place because:

A solution contains [Ba2+] = 5.0 × 10-5 M, [Ag+] = 3.0 × 10-5 M, and [Zn2+] = 2.0 × 10-7 M. Sodium oxalate is slowly added so that [C2O42-] increases. Salt BaC2O4 ZnC2O4 Ag2C2O4 Ksp 1.5 × 10-8 1.35 × 10-9 1.1 × 10-11 Which one of the oxalates precipitates first?

If iron(III) acetate is added to be 1 × 10-10 M in a solution that is 0.10 M NH3, what is Qsp and will Fe(OH)3 precipitate? The Ksp of Fe(OH)3 is 4 × 10-38 and Kb for NH3 is 1.8 × 10-5.

Predict the molar solubility of the following salt in a solution that contains the given concentration of one of its ions: BaSO4; [SO42-] = 4.3 × 10-5 M; Ksp = 1.1 × 10-10

The solubility product constant of Mg(OH)2 is 9.0 × 10-12. If a solution is 0.010 M with respect to Mg2+ ion, the amount of [OH-] required to start the precipitation of Mg(OH)2 is:

In which of the following solutions will the concentration of dissolved silver species be the highest if solid AgNO3 is stirred with 1.00 L of solution?

The solubility of cerium iodate, Ce(IO3)3, molar mass = 664.83 g/mol, in pure water is 124 mg per 100 mL of water. Calculate the solubility product constant for cerium iodate.

Some solid in a solution at equilibrium means the solution is saturated.

Which of the following salts, each of which has a solubility product equal to 1.0 × 10-6, has the greatest molar solubility?

Write the solubility product constant expression for the following salt: PbC2O4.

When 200 mL of 0.10 M BaCl2 is added to 100 mL of 0.30 M Na2SO4, the number of moles of BaSO4 (solubility product = 1.1 × 10-10) precipitated is ________.

When equal volumes of the indicated solutions are mixed, precipitation should occur only for: barium fluoride 1.0 × 10-6 calcium carbonate 2.8 × 10-9 Calcium fluoride 5.3 × 10-9 Magnesium fluoride 3.7 × 10-8 Silver carbonate 8.5 × 10-12

When equal volumes of the indicated solutions are mixed, precipitation should occur only for: barium fluoride 1.0 × 10-6 calcium carbonate 2.8 × 10-9 Calcium fluoride 5.3 × 10-9 Magnesium fluoride 3.7 × 10-9 Silver carbonate 8.5 × 10-12

What ratio of [NH4+]/[NH3] would provide a buffer of pH low enough to avoid precipitation of Co(OH)2 [Ksp = 2.0 × 10-14] from a 0.50 M Co2+ solution? [Kb for NH3 = 1.8 × 10-5]

What is the concentration of Ca2+ in ppm (mg/L) in cave water saturated with calcite (calcium carbonate, Ksp = 4.7 × 10-9)?

What is the free Cu2+ concentration if 0.020 M Cu2+ solution is mixed with an equal volume of 4.0 M NH3? Kf for [Cu(NH3)4]2+ is 1.1 × 1013.

Matter - Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Additional Aspects

Intermolecular Forces: Liquids and Solids

Solutions and Their Physical Properties

Chemical Kinetics

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acid-Base Equilibria

Spontaneous Change: Entropy and Free Energy

Electrochemistry

Main Group Elements I: Groups 1, 2, 13, and 14

Main Group Elements II: Groups 18, 17, 16, 15, and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry 1-41

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

Filters

Fe(OH)₃ is most soluble in which solution?

Which of the following soil additives would best reduce the concentration of dissolved Fe³⁺ in ground water?

If iron(III) acetate is added to be 1 × 10^-10 M in a solution that is 0.10 M NH₃, what is Qsp and will Fe(OH)₃ precipitate? The Ksp of Fe(OH)₃ is 4 × 10^-38 and Kb for NH₃ is 1.8 × 10^-5.

Predict the molar solubility of the following salt in a solution that contains the given concentration of one of its ions: BaSO₄; [SO₄^2-] = 4.3 × 10^-5 M; Ksp = 1.1 × 10^-10

The solubility product constant of Mg(OH)₂ is 9.0 × 10^-12. If a solution is 0.010 M with respect to Mg²⁺ ion, the amount of [OH-] required to start the precipitation of Mg(OH)₂ is:

In which of the following solutions will the concentration of dissolved silver species be the highest if solid AgNO₃ is stirred with 1.00 L of solution?

The solubility of cerium iodate, Ce(IO₃)₃, molar mass = 664.83 g/mol, in pure water is 124 mg per 100 mL of water. Calculate the solubility product constant for cerium iodate.

Which of the following salts, each of which has a solubility product equal to 1.0 × 10^-6, has the greatest molar solubility?

Write the solubility product constant expression for the following salt: PbC₂O₄.

When 200 mL of 0.10 M BaCl₂ is added to 100 mL of 0.30 M Na₂SO₄, the number of moles of BaSO₄ (solubility product = 1.1 × 10^-10) precipitated is ________.

When equal volumes of the indicated solutions are mixed, precipitation should occur only for: barium fluoride 1.0 × 10^-6 calcium carbonate 2.8 × 10^-9 Calcium fluoride 5.3 × 10^-9 Magnesium fluoride 3.7 × 10^-8 Silver carbonate 8.5 × 10^-12

When equal volumes of the indicated solutions are mixed, precipitation should occur only for: barium fluoride 1.0 × 10^-6 calcium carbonate 2.8 × 10^-9 Calcium fluoride 5.3 × 10^-9 Magnesium fluoride 3.7 × 10^-9 Silver carbonate 8.5 × 10-12

What ratio of [NH₄⁺]/[NH₃] would provide a buffer of pH low enough to avoid precipitation of Co(OH)₂ [Ksp = 2.0 × 10^-14] from a 0.50 M Co²⁺ solution? [Kb for NH₃ = 1.8 × 10^-5]

What is the concentration of Ca²⁺ in ppm (mg/L) in cave water saturated with calcite (calcium carbonate, Ksp = 4.7 × 10^-9)?

What is the free Cu²⁺ concentration if 0.020 M Cu²⁺ solution is mixed with an equal volume of 4.0 M NH₃? Kf for [Cu(NH₃)₄]²⁺ is 1.1 × 10¹³.