Question 1

The common ion effect is a case of Hess's law.

Accepted Answer

A) True 
 B)False  False

Question 2

Choose the compound that is most soluble in water.

Accepted Answer

A)  K2S 
B)  HgS 
C)  ZnS 
D)  SnS 
E)  PbS 
A)  K2S 
B)  HgS 
C)  ZnS 
D)  SnS 
E)  PbS A

Question 3

The solubility of a salt MX2 with a molar mass of 170 g/mol is 12.7 g/liter. Calculate the Ksp.

Accepted Answer

A)  4.17 × 10-4 
B)  5.58 × 10-3 
C)  9.59 × 103 
D)  2.23 × 10-2 
E)  1.67 × 10-3 
A)  4.17 × 10-4 
B)  5.58 × 10-3 
C)  9.59 × 103 
D)  2.23 × 10-2 
E)  1.67 × 10-3 E

Question 4

Which of the following is least soluble?

Accepted Answer

A)  NiS (Ksp = 8 × 10-37) 
B)  MnS (Ksp = 8 × 10-16) 
C)  PtS (Ksp = 8 × 10-73) 
D)  FeS (Ksp = 4 × 10-19) 
E)  Hg2Cl2 (Ksp = 1.3 × 10-18) 
A)  NiS (Ksp = 8 × 10-37) 
B)  MnS (Ksp = 8 × 10-16) 
C)  PtS (Ksp = 8 × 10-73) 
D)  FeS (Ksp = 4 × 10-19) 
E)  Hg2Cl2 (Ksp = 1.3 × 10-18)

Question 5

In which of the following one molar solutions would you expect cadmium sulfide, CdS, to be the most soluble?

Accepted Answer

A)  NaCl 
B)  HCl 
C)  NaOH 
D)  C2H5OH 
E)  KOH 
A)  NaCl 
B)  HCl 
C)  NaOH 
D)  C2H5OH 
E)  KOH

Question 6

In a qualitative cation analysis, the unknown ion is not precipitated by HCl, H2S, or CO32-. A flame test produced a violet flame. The unknown ion is ________.

Accepted Answer

A)  Ag+ 
B)  Pb2+ 
C)  Fe2+ 
D)  K+ 
E)  NH4+ 
A)  Ag+ 
B)  Pb2+ 
C)  Fe2+ 
D)  K+ 
E)  NH4+

Question 7

The solubility product constant of PbI2 is 7.1 × 10-9. How many moles of PbI2 will precipitate if 250 ml of a 0.200 M solution of NaI are added to 150 ml of 0.100 M solution of Pb(NO3)2? You may neglect hydrolysis.

Accepted Answer

A)  0.050 mol 
B)  1.3 × 10-5 mol 
C)  0.015 mol 
D)  5.6 × 10-3 mol 
E)  0.040 mol 
A)  0.050 mol 
B)  1.3 × 10-5 mol 
C)  0.015 mol 
D)  5.6 × 10-3 mol 
E)  0.040 mol

Question 8

If chromium(III) chloride is added to be 1 × 10-12 M in a solution that is 0.10 M NH3, what is Qsp and will Cr(OH)3 precipitate? The Ksp of Cr(OH)3 is 6.3 × 10-31 and Kb for NH3 is 1.8 × 10-5.

Accepted Answer

A)  1.0 × 10-16, yes 
B)  2.4 × 10-23, no 
C)  2.2 × 10-19, no 
D)  2.2 × 10-19, yes 
E)  2.4 × 10-21, yes 
A)  1.0 × 10-16, yes 
B)  2.4 × 10-23, no 
C)  2.2 × 10-19, no 
D)  2.2 × 10-19, yes 
E)  2.4 × 10-21, yes

Question 9

Write the solubility product constant expression for the following salt: Ag2SO4.

Accepted Answer

A)  [Ag+][SO42-] 
B)  [Ag+]2[SO42-] 
C)  4[Ag+]2[SO42-] 
D)  [Ag+][SO42-]2 
E)  [Ag+]2[SO42-]2 
A)  [Ag+][SO42-] 
B)  [Ag+]2[SO42-] 
C)  4[Ag+]2[SO42-] 
D)  [Ag+][SO42-]2 
E)  [Ag+]2[SO42-]2

Question 10

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

Question 11

Saturated solutions of sodium sulfate, ammonium carbonate, and nickel (II) nitrate are mixed together. The precipitate that forms is ________.

Accepted Answer

A)  nickel (II) carbonate 
B)  sodium carbonate 
C)  nickel (II) sulfate 
D)  ammonium sulfate 
E)  sodium nitrate 
A)  nickel (II) carbonate 
B)  sodium carbonate 
C)  nickel (II) sulfate 
D)  ammonium sulfate 
E)  sodium nitrate

Question 12

Concentrated solutions of iron (III) chloride, sodium hydroxide, and potassium nitrate are mixed together. The precipitate which forms is ________.

Accepted Answer

A)  potassium hydroxide 
B)  sodium chloride 
C)  iron (III) hydroxide 
D)  nothing precipitates 
E)  iron (III) nitrate 
A)  potassium hydroxide 
B)  sodium chloride 
C)  iron (III) hydroxide 
D)  nothing precipitates 
E)  iron (III) nitrate

Question 13

What is the free Ag+ concentration of 0.020 M Ag+ solution mixed with an equal volume of 2.0 M NH3? Kf for [Ag(NH3)2]+ is 1.6 × 107.

Accepted Answer

A)  1.3 × 10-10 
B)  2.0 × 10-14 
C)  6.3 × 10-8 
D)  6.5 × 10-10 
E)  3.1 × 10-10 
A)  1.3 × 10-10 
B)  2.0 × 10-14 
C)  6.3 × 10-8 
D)  6.5 × 10-10 
E)  3.1 × 10-10

Question 14

In a qualitative cation analysis, the unknown ion is unaffected by HCl, but is precipitated by hydrogen sulfide. The unknown ion is ________.

Accepted Answer

A)  NH4+ 
B)  Cu2+ 
C)  Ag+ 
D)  K+ 
E)  Na+ 
A)  NH4+ 
B)  Cu2+ 
C)  Ag+ 
D)  K+ 
E)  Na+

Question 15

The molar solubility of SrSO4 (Ksp = 7.6 × 10-7) is:

Accepted Answer

A)  2.8 × 10-5 M 
B)  7.6 × 10-7 M 
C)  8.7 × 10-8 M 
D)  8.7 × 10-4 M 
E)  9.1 × 10-3 M 
A)  2.8 × 10-5 M 
B)  7.6 × 10-7 M 
C)  8.7 × 10-8 M 
D)  8.7 × 10-4 M 
E)  9.1 × 10-3 M

Question 16

To a concentrated buffer of pH 4.0 is added an equal volume of a solution that is 0.020 M in Cr3+, Cd2+ and Al3+. The expected precipitate would consist of ________. 
salt: chromium(III) hydroxide   &emsp; cadmium hydroxide   &emsp; aluminum hydroxide
Ksp   &emsp;6.3 × 10-31   &emsp;   &emsp;  &emsp;  &emsp;  &emsp;  &emsp;2.5 × 10-14     &emsp;  &emsp;  &emsp;&emsp; 1.3 × 10-33

Accepted Answer

A)  Al(OH)3 
B)  Al(OH)3 and Cr(OH)3 
C)  Cd(OH)2 
D)  Cd(OH)2 and Cr(OH)3 
E)  Cd(OH)2, Cr(OH)3 and Al(OH)3 
A)  Al(OH)3 
B)  Al(OH)3 and Cr(OH)3 
C)  Cd(OH)2 
D)  Cd(OH)2 and Cr(OH)3 
E)  Cd(OH)2, Cr(OH)3 and Al(OH)3

Question 17

In a qualitative cation analysis, the unknown ion is precipitated by HCl, remains as a chloride solid in hot water, and the precipitate turns black upon addition of ammonia. The unknown ion is ________.

Accepted Answer

A)  Hg22+ 
B)  Pb2+ 
C)  Ag+ 
D)  K+ 
E)  Cd2+ 
A)  Hg22+ 
B)  Pb2+ 
C)  Ag+ 
D)  K+ 
E)  Cd2+

Question 18

A concentrated buffer of pH 8.0 is added to an equal volume of a solution that is 0.080 M in each of the ions Zn2+, Ni2+, and Mn2+. The expected precipitate would consist of ________. salt: zinc hydroxide nickel hydroxide manganese hydroxide
Ksp 1.2 × 10-17  &emsp;  2.0 × 10-15  &emsp;  1.9 × 10-13

Accepted Answer

A)  Zn(OH)2, Ni(OH)2 and Mn(OH)2 
B)  Ni(OH)2 and Mn(OH)2 
C)  Mn(OH)2 
D)  Ni(OH)2 and Zn(OH)2 
E)  Zn(OH)2 
A)  Zn(OH)2, Ni(OH)2 and Mn(OH)2 
B)  Ni(OH)2 and Mn(OH)2 
C)  Mn(OH)2 
D)  Ni(OH)2 and Zn(OH)2 
E)  Zn(OH)2

Question 19

When 100 mL each of 2.0 × 10-4 M Ca2+ and 2.0 × 10-2 M F- are mixed, what is the remaining Ca2+ ion concentration and is precipitation complete? The solubility product constant of CaF2 is 5.3 × 10-9.

Accepted Answer

A)  5.6 × 10-4, no 
B)  1.7 × 10-8, yes 
C)  4.3 × 10-7, no 
D)  1.7 × 10-6, yes 
E)  5.4 × 10-5, no 
A)  5.6 × 10-4, no 
B)  1.7 × 10-8, yes 
C)  4.3 × 10-7, no 
D)  1.7 × 10-6, yes 
E)  5.4 × 10-5, no

Question 20

At a temperature for which the solubility product constant of calcium carbonate is 4.7 × 10-9, what mass of the salt will dissolve in 100 mL of water?

Accepted Answer

A)  0.69 mg 
B)  0.94 mg 
C)  1.2 mg 
D)  2.4 mg 
E)  4.7 mg 
A)  0.69 mg 
B)  0.94 mg 
C)  1.2 mg 
D)  2.4 mg 
E)  4.7 mg

Exam 18: Solubility and Complex-Ion Equilibria

The common ion effect is a case of Hess's law.

Choose the compound that is most soluble in water.

The solubility of a salt MX2 with a molar mass of 170 g/mol is 12.7 g/liter. Calculate the Ksp.

Which of the following is least soluble?

In which of the following one molar solutions would you expect cadmium sulfide, CdS, to be the most soluble?

In a qualitative cation analysis, the unknown ion is not precipitated by HCl, H2S, or CO32-. A flame test produced a violet flame. The unknown ion is ________.

The solubility product constant of PbI2 is 7.1 × 10-9. How many moles of PbI2 will precipitate if 250 ml of a 0.200 M solution of NaI are added to 150 ml of 0.100 M solution of Pb(NO3)2? You may neglect hydrolysis.

If chromium(III) chloride is added to be 1 × 10-12 M in a solution that is 0.10 M NH3, what is Qsp and will Cr(OH)3 precipitate? The Ksp of Cr(OH)3 is 6.3 × 10-31 and Kb for NH3 is 1.8 × 10-5.

Write the solubility product constant expression for the following salt: Ag2SO4.

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

Saturated solutions of sodium sulfate, ammonium carbonate, and nickel (II) nitrate are mixed together. The precipitate that forms is ________.

Concentrated solutions of iron (III) chloride, sodium hydroxide, and potassium nitrate are mixed together. The precipitate which forms is ________.

What is the free Ag+ concentration of 0.020 M Ag+ solution mixed with an equal volume of 2.0 M NH3? Kf for [Ag(NH3)2]+ is 1.6 × 107.

In a qualitative cation analysis, the unknown ion is unaffected by HCl, but is precipitated by hydrogen sulfide. The unknown ion is ________.

The molar solubility of SrSO4 (Ksp = 7.6 × 10-7) is:

To a concentrated buffer of pH 4.0 is added an equal volume of a solution that is 0.020 M in Cr3+, Cd2+ and Al3+. The expected precipitate would consist of ________. salt: chromium(III) hydroxide cadmium hydroxide aluminum hydroxide Ksp 6.3 × 10-31 2.5 × 10-14 1.3 × 10-33

In a qualitative cation analysis, the unknown ion is precipitated by HCl, remains as a chloride solid in hot water, and the precipitate turns black upon addition of ammonia. The unknown ion is ________.

A concentrated buffer of pH 8.0 is added to an equal volume of a solution that is 0.080 M in each of the ions Zn2+, Ni2+, and Mn2+. The expected precipitate would consist of ________. salt: zinc hydroxide nickel hydroxide manganese hydroxide Ksp 1.2 × 10-17 2.0 × 10-15 1.9 × 10-13

When 100 mL each of 2.0 × 10-4 M Ca2+ and 2.0 × 10-2 M F- are mixed, what is the remaining Ca2+ ion concentration and is precipitation complete? The solubility product constant of CaF2 is 5.3 × 10-9.

At a temperature for which the solubility product constant of calcium carbonate is 4.7 × 10-9, what mass of the salt will dissolve in 100 mL of water?

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

In a qualitative cation analysis, the unknown ion is not precipitated by HCl, H₂S, or CO₃^2-. A flame test produced a violet flame. The unknown ion is ________.

The solubility product constant of PbI2 is 7.1 × 10^-9. How many moles of PbI2 will precipitate if 250 ml of a 0.200 M solution of NaI are added to 150 ml of 0.100 M solution of Pb(NO₃)₂? You may neglect hydrolysis.

If chromium(III) chloride is added to be 1 × 10^-12 M in a solution that is 0.10 M NH₃, what is Qsp and will Cr(OH)₃ precipitate? The Ksp of Cr(OH)₃ is 6.3 × 10^-31 and Kb for NH₃ is 1.8 × 10^-5.

Write the solubility product constant expression for the following salt: Ag₂SO₄.

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

What is the free Ag⁺ concentration of 0.020 M Ag⁺ solution mixed with an equal volume of 2.0 M NH₃? Kf for [Ag(NH₃)₂]⁺ is 1.6 × 10⁷.

The molar solubility of SrSO₄ (Ksp = 7.6 × 10^-7) is:

To a concentrated buffer of pH 4.0 is added an equal volume of a solution that is 0.020 M in Cr3⁺, Cd²⁺ and Al³⁺. The expected precipitate would consist of ________. salt: chromium(III) hydroxide cadmium hydroxide aluminum hydroxide Ksp 6.3 × 10^-31 2.5 × 10^-14 1.3 × 10^-33

A concentrated buffer of pH 8.0 is added to an equal volume of a solution that is 0.080 M in each of the ions Zn²⁺, Ni²⁺, and Mn²⁺. The expected precipitate would consist of ________. salt: zinc hydroxide nickel hydroxide manganese hydroxide Ksp 1.2 × 10^-17 2.0 × 10-¹⁵ 1.9 × 10^-13

When 100 mL each of 2.0 × 10^-4 M Ca²⁺ and 2.0 × 10^-2M F- are mixed, what is the remaining Ca²⁺ ion concentration and is precipitation complete? The solubility product constant of CaF₂ is 5.3 × 10^-9.

At a temperature for which the solubility product constant of calcium carbonate is 4.7 × 10^-9, what mass of the salt will dissolve in 100 mL of water?