Question 1

Consider the dissolution of MnS in water (Ksp = 3.0 × 10-14) . MnS(s)  + H2O(l)  sp = 3.0 × 10-14) . MnS(s)  + H2O(l)    Mn2+(aq)  + HS-(aq)  + OH-(aq)  How is the solubility of manganese(II)  sulfide affected by the addition of aqueous potassium hydroxide to the system? A)  The solubility will be unchanged. B)  The solubility will decrease. C)  The solubility will increase. D)  The amount of KOH added must be known before its effect can be predicted. E)  The pKa of H2S is needed before a reliable prediction can be made." class="answers-bank-image d-inline" rel="preload" > Mn2+(aq)  + HS-(aq)  + OH-(aq) 
How is the solubility of manganese(II)  sulfide affected by the addition of aqueous potassium hydroxide to the system?

Accepted Answer

A)   The solubility will be unchanged.
B)   The solubility will decrease.
C)   The solubility will increase.
D)   The amount of KOH added must be known before its effect can be predicted.
E)   The pKa of H2S is needed before a reliable prediction can be made.F) A) and E)
G) A) and B)

Question 2

The pH of blood is 7.35. It is maintained in part by the buffer system composed of carbonic acid (H2CO3)  and the bicarbonate (hydrogen carbonate, HCO3-)  ion. What is the ratio of [bicarbonate]/[carbonic acid] at this pH? For carbonic acid, Ka1 = 4.2 × 10-7.

Accepted Answer

A)   [bicarbonate]/[carbonic acid] = 0.11
B)   [bicarbonate]/[carbonic acid] = 0.38
C)   [bicarbonate]/[carbonic acid] = 2.65
D)   [bicarbonate]/[carbonic acid] = 9.4
E)   None of these choices are correct.F) B) and D)
G) C) and E)

Question 3

When a strong acid is titrated with a strong base, the pH at the equivalence point

Accepted Answer

A)   is greater than 7.0.
B)   is equal to 7.0.
C)   is less than 7.0, but is not 3.5.
D)   is equal to the pKa of the acid.
E)   is equal to 3.5.F) B) and C)
G) D) and E)

Question 4

The solubility of calcium chromate is 1.56 × 10-3 g/100 mL of solution. What is the Ksp for CaCrO4?

Accepted Answer

A)   2.4 × 10-4
B)   1.5 × 10-5
C)   7.6 × 10-6
D)   1.0 × 10-8
E)   -8F) A) and E)
G) A) and D)

Question 5

Write the ion product expression for silver sulfide, Ag2S.

Accepted Answer

A)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
B)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
C)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
D)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
E)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >F) None of the above
G) A) and B)

Question 6

A saturated solution of calcium hydroxide, Ca(OH) 2, is in contact with excess solid Ca(OH) 2. Which of the following statements correctly describes what will happen when aqueous HCl (a strong acid)  is added to this mixture, and system returns to equilibrium? (For Ca(OH) 2, Ksp = 6.5 × 10-6)

Accepted Answer

A)   The solubility of Ca(OH) 2 will be unchanged.
B)   The OH- concentration will decrease and the Ca2+ concentration will increase.
C)   The OH- concentration will increase and the Ca2+ concentration will decrease.
D)   The concentrations of both Ca2+ and OH- will increase.
E)   The solubility of Ca(OH) 2 will decrease.F) None of the above
G) A) and B)

Question 7

Which of the following substances has the greatest solubility in water?

Accepted Answer

A)   PbI2, Ksp = 7.9 × 10-9
B)   BaF2, Ksp = 1.5 × 10-6
C)   Ca(OH) 2, Ksp = 6.5 × 10-6
D)   Zn(IO3) 2, Ksp = 3.9 × 10-6
E)   Ag2SO4, Ksp = 1.5 × 10-5F) A) and B)
G) A) and C)

Question 8

You need to prepare a buffer solution with a pH of 4.00, using NaF and HF. What ratio of the ratio of [base]/[acid] should be used in making the buffer? For HF, Ka = 7.2 × 10-4.

Accepted Answer

A)   [base]/[acid] = 0.14
B)   [base]/[acid] = 0.42
C)   [base]/[acid] = 2.36
D)   [base]/[acid] = 7.20
E)   None of these choices are correct.F) All of the above
G) A) and B)

Question 9

A diprotic acid H2A has Ka1 = 1 × 10-4 and Ka2 = 1 × 10-8. The corresponding base A2- is titrated with aqueous HCl, both solutions being 0.1 mol L-1. Which one of the following diagrams best represents the titration curve which will be seen? 2A has Ka1 = 1 × 10-4 and Ka2 = 1 × 10-8. The corresponding base A2- is titrated with aqueous HCl, both solutions being 0.1 mol L-1. Which one of the following diagrams best represents the titration curve which will be seen?   A)  A B)  B C)  C D)  D E)  E" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   A
B)   B
C)   C
D)   D
E)   EF) D) and E)
G) A) and E)

Question 10

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak diprotic acid H2A (0.10 mol L-1)  with a strong base of the same concentration? 2A (0.10 mol L-1)  with a strong base of the same concentration?    A) A B)  B C)  C D)  D E)  E" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)  A
B)   B
C)   C
D)   D
E)   EF) A) and B)
G) D) and E)

Question 11

A 25.0-mL sample of 0.10 M C2H3NH2 (ethylamine)  is titrated with 0.15 M HCl. What is the Ph of the solution after 9.00 mL of acid have been added to the amine? Kb = 6.5 × 10-4

Accepted Answer

A)   11.08
B)   10.88
C)   10.74
D)   10.55
E)   10.49F) A) and E)
G) A) and D)

Question 12

When a weak acid is titrated with a strong base, the pH at the equivalence point

Accepted Answer

A)   is greater than 7.0.
B)   is equal to 7.0.
C)   is less than 7.0.
D)   is equal to the pKa of the acid.
E)   is equal to 14.0 - pKb, where pKb is that of the base.F) C) and D)
G) All of the above

Question 13

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak base (0.10 mol L-1)  with HCl of the same concentration? -1)  with HCl of the same concentration?   A)  A B)  B C)  C D)  D E)  E" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)   A
B)   B
C)   C
D)   D
E)   EF) D) and E)
G) All of the above

Question 14

If the pH of a buffer solution is greater than the pKa value of the buffer acid, the buffer will have more capacity to neutralize added base than added acid.

Accepted Answer

A) True 
 B)False

Question 15

What volume of 0.200 M KOH must be added to 17.5 mL of 0.135 M H3PO4 to reach the third equivalence point?

Accepted Answer

A)   3.94 mL
B)   11.8 mL
C)   17.5 mL
D)   23.6 mL
E)   35.4 mLF) B) and C)
G) All of the above

Question 16

Buffer solutions with the component concentrations shown below were prepared. Which of them should have the highest pH?

Accepted Answer

A)   [H2PO4-] = 0.50 M, [HPO42-] = 0.50 M
B)   [H2PO4-] = 1.0 M, [HPO42-] = 1.0 M
C)   [H2PO4-] = 1.0 M, [HPO42-] = 0.50 M
D)   [H2PO4-] = 0.50 M, [HPO42-] = 1.0 M
E)   [H2PO4-] = 0.75 M, [HPO42-] = 1.0 MF) A) and C)
G) B) and E)

Question 17

A solution is prepared by dissolving 20.0 g of K2HPO4 and 25.0 g of KH2PO4 in enough water to produce 1.0 L of solution. What is the pH of this buffer? For phosphoric acid (H3PO4) , Ka2 = 6.2 × 10-8.

Accepted Answer

A)   7.70
B)   7.42
C)   7.21
D)   7.00
E)   6.72F) A) and B)
G) B) and E)

Question 18

What is the pH of a solution that consists of 0.50 M H2C6H6O6 (ascorbic acid)  and 0.75 M NaHC6H6O6 (sodium ascorbate) ? For ascorbic acid, Ka = 6.8 × 10-5

Accepted Answer

A)   3.76
B)   3.99
C)   4.34
D)   4.57
E)   5.66F) None of the above
G) B) and C)

Question 19

Calculate the solubility of zinc hydroxide, Zn(OH) 2, in 1.00 M NaOH. Ksp = 3.0 × 10-16 for Zn(OH) 2, Kf = 3.0 × 1015 for Zn(OH) 42-

Accepted Answer

A)   0.60 M
B)   0.52 M
C)   0.37 M
D)   0.32 M
E)   0.24 MF) C) and D)
G) None of the above

Question 20

A 25.0-mL sample of 0.35 M HCOOH is titrated with 0.20 M KOH. What is the pH of the solution after 25.0 mL of KOH has been added to the acid? Ka = 1.77 × 10-4

Accepted Answer

A)   4.00
B)   3.88
C)   3.63
D)   3.51
E)   3.47F) A) and B)
G) A) and E)

Exam 19: Ionic Equilibria in Aqueous Systems

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak diprotic acid H₂A (0.10 mol L^-1) with a strong base of the same concentration?

Correct Answer
verified

When a weak acid is titrated with a strong base, the pH at the equivalence point

Correct Answer
verified

The pH of blood is 7.35. It is maintained in part by the buffer system composed of carbonic acid (H₂CO₃) and the bicarbonate (hydrogen carbonate, HCO₃^-) ion. What is the ratio of [bicarbonate]/[carbonic acid] at this pH? For carbonic acid, K_a1 = 4.2 × 10^-7.

Correct Answer
verified

What volume of 0.200 M KOH must be added to 17.5 mL of 0.135 M H₃PO₄ to reach the third equivalence point?

Correct Answer
verified

Write the ion product expression for silver sulfide, Ag₂S.

Correct Answer
verified

When a strong acid is titrated with a strong base, the pH at the equivalence point

Correct Answer
verified

Which of the following substances has the greatest solubility in water?

Correct Answer
verified

A diprotic acid H₂A has K_a1 = 1 × 10^-4 and K_a2 = 1 × 10^-8. The corresponding base A^2- is titrated with aqueous HCl, both solutions being 0.1 mol L^-1. Which one of the following diagrams best represents the titration curve which will be seen?

Correct Answer
verified

Calculate the solubility of zinc hydroxide, Zn(OH) ₂, in 1.00 M NaOH. K_sp = 3.0 × 10^-16 for Zn(OH) ₂, K_f = 3.0 × 10¹⁵ for Zn(OH) ₄^2-

Correct Answer
verified

Consider the dissolution of MnS in water (K_sp = 3.0 × 10^-14) . MnS(s) + H₂O(l) Mn²⁺(aq) + HS^-(aq) + OH^-(aq) How is the solubility of manganese(II) sulfide affected by the addition of aqueous potassium hydroxide to the system?

Correct Answer
verified

A 25.0-mL sample of 0.10 M C₂H₃NH₂ (ethylamine) is titrated with 0.15 M HCl. What is the Ph of the solution after 9.00 mL of acid have been added to the amine? K_b = 6.5 × 10^-4

Correct Answer
verified

What is the pH of a solution that consists of 0.50 M H₂C₆H₆O₆ (ascorbic acid) and 0.75 M NaHC₆H₆O₆ (sodium ascorbate) ? For ascorbic acid, K_a = 6.8 × 10^-5

Correct Answer
verified

Buffer solutions with the component concentrations shown below were prepared. Which of them should have the highest pH?

Correct Answer
verified

A 25.0-mL sample of 0.35 M HCOOH is titrated with 0.20 M KOH. What is the pH of the solution after 25.0 mL of KOH has been added to the acid? K_a = 1.77 × 10^-4

Correct Answer
verified

If the pH of a buffer solution is greater than the pK_a value of the buffer acid, the buffer will have more capacity to neutralize added base than added acid.

Correct Answer
verified

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak base (0.10 mol L^-1) with HCl of the same concentration?

Correct Answer
verified

You need to prepare a buffer solution with a pH of 4.00, using NaF and HF. What ratio of the ratio of [base]/[acid] should be used in making the buffer? For HF, K_a = 7.2 × 10^-4.

Correct Answer
verified

Correct Answer
verified

The solubility of calcium chromate is 1.56 × 10^-3 g/100 mL of solution. What is the K_sp for CaCrO₄?

Correct Answer
verified

A solution is prepared by dissolving 20.0 g of K₂HPO₄ and 25.0 g of KH₂PO₄ in enough water to produce 1.0 L of solution. What is the pH of this buffer? For phosphoric acid (H₃PO₄) , K_a2 = 6.2 × 10^-8.

Correct Answer
verified

Exam 19: Ionic Equilibria in Aqueous Systems

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak diprotic acid H2A (0.10 mol L-1) with a strong base of the same concentration?

Correct AnswerverifiedShow Answer

When a weak acid is titrated with a strong base, the pH at the equivalence point

Correct AnswerverifiedShow Answer

The pH of blood is 7.35. It is maintained in part by the buffer system composed of carbonic acid (H2CO3) and the bicarbonate (hydrogen carbonate, HCO3-) ion. What is the ratio of [bicarbonate]/[carbonic acid] at this pH? For carbonic acid, Ka1 = 4.2 × 10-7.

Correct AnswerverifiedShow Answer

What volume of 0.200 M KOH must be added to 17.5 mL of 0.135 M H3PO4 to reach the third equivalence point?

Correct AnswerverifiedShow Answer

Write the ion product expression for silver sulfide, Ag2S.

Correct AnswerverifiedShow Answer

When a strong acid is titrated with a strong base, the pH at the equivalence point

Correct AnswerverifiedShow Answer

Which of the following substances has the greatest solubility in water?

Correct AnswerverifiedShow Answer

A diprotic acid H2A has Ka1 = 1 × 10-4 and Ka2 = 1 × 10-8. The corresponding base A2- is titrated with aqueous HCl, both solutions being 0.1 mol L-1. Which one of the following diagrams best represents the titration curve which will be seen?

Correct AnswerverifiedShow Answer

Calculate the solubility of zinc hydroxide, Zn(OH) 2, in 1.00 M NaOH. Ksp = 3.0 × 10-16 for Zn(OH) 2, Kf = 3.0 × 1015 for Zn(OH) 42-

Correct AnswerverifiedShow Answer

Consider the dissolution of MnS in water (Ksp = 3.0 × 10-14) . MnS(s) + H2O(l) Mn2+(aq) + HS-(aq) + OH-(aq) How is the solubility of manganese(II) sulfide affected by the addition of aqueous potassium hydroxide to the system?

Correct AnswerverifiedShow Answer

A 25.0-mL sample of 0.10 M C2H3NH2 (ethylamine) is titrated with 0.15 M HCl. What is the Ph of the solution after 9.00 mL of acid have been added to the amine? Kb = 6.5 × 10-4

Correct AnswerverifiedShow Answer

What is the pH of a solution that consists of 0.50 M H2C6H6O6 (ascorbic acid) and 0.75 M NaHC6H6O6 (sodium ascorbate) ? For ascorbic acid, Ka = 6.8 × 10-5

Correct AnswerverifiedShow Answer

Buffer solutions with the component concentrations shown below were prepared. Which of them should have the highest pH?

Correct AnswerverifiedShow Answer

A 25.0-mL sample of 0.35 M HCOOH is titrated with 0.20 M KOH. What is the pH of the solution after 25.0 mL of KOH has been added to the acid? Ka = 1.77 × 10-4

Correct AnswerverifiedShow Answer

If the pH of a buffer solution is greater than the pKa value of the buffer acid, the buffer will have more capacity to neutralize added base than added acid.

Correct AnswerverifiedShow Answer

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak base (0.10 mol L-1) with HCl of the same concentration?

Correct AnswerverifiedShow Answer

You need to prepare a buffer solution with a pH of 4.00, using NaF and HF. What ratio of the ratio of [base]/[acid] should be used in making the buffer? For HF, Ka = 7.2 × 10-4.

Correct AnswerverifiedShow Answer

A saturated solution of calcium hydroxide, Ca(OH) 2, is in contact with excess solid Ca(OH) 2. Which of the following statements correctly describes what will happen when aqueous HCl (a strong acid) is added to this mixture, and system returns to equilibrium? (For Ca(OH) 2, Ksp = 6.5 × 10-6)

Correct AnswerverifiedShow Answer

The solubility of calcium chromate is 1.56 × 10-3 g/100 mL of solution. What is the Ksp for CaCrO4?

Correct AnswerverifiedShow Answer

A solution is prepared by dissolving 20.0 g of K2HPO4 and 25.0 g of KH2PO4 in enough water to produce 1.0 L of solution. What is the pH of this buffer? For phosphoric acid (H3PO4) , Ka2 = 6.2 × 10-8.

Correct AnswerverifiedShow Answer

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak diprotic acid H₂A (0.10 mol L^-1) with a strong base of the same concentration?

Correct Answer
verified

Correct Answer
verified

The pH of blood is 7.35. It is maintained in part by the buffer system composed of carbonic acid (H₂CO₃) and the bicarbonate (hydrogen carbonate, HCO₃^-) ion. What is the ratio of [bicarbonate]/[carbonic acid] at this pH? For carbonic acid, K_a1 = 4.2 × 10^-7.

Correct Answer
verified

What volume of 0.200 M KOH must be added to 17.5 mL of 0.135 M H₃PO₄ to reach the third equivalence point?

Correct Answer
verified

Write the ion product expression for silver sulfide, Ag₂S.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

A diprotic acid H₂A has K_a1 = 1 × 10^-4 and K_a2 = 1 × 10^-8. The corresponding base A^2- is titrated with aqueous HCl, both solutions being 0.1 mol L^-1. Which one of the following diagrams best represents the titration curve which will be seen?

Correct Answer
verified

Calculate the solubility of zinc hydroxide, Zn(OH) ₂, in 1.00 M NaOH. K_sp = 3.0 × 10^-16 for Zn(OH) ₂, K_f = 3.0 × 10¹⁵ for Zn(OH) ₄^2-

Correct Answer
verified

Consider the dissolution of MnS in water (K_sp = 3.0 × 10^-14) . MnS(s) + H₂O(l) Mn²⁺(aq) + HS^-(aq) + OH^-(aq) How is the solubility of manganese(II) sulfide affected by the addition of aqueous potassium hydroxide to the system?

Correct Answer
verified

A 25.0-mL sample of 0.10 M C₂H₃NH₂ (ethylamine) is titrated with 0.15 M HCl. What is the Ph of the solution after 9.00 mL of acid have been added to the amine? K_b = 6.5 × 10^-4

Correct Answer
verified

What is the pH of a solution that consists of 0.50 M H₂C₆H₆O₆ (ascorbic acid) and 0.75 M NaHC₆H₆O₆ (sodium ascorbate) ? For ascorbic acid, K_a = 6.8 × 10^-5

Correct Answer
verified

Correct Answer
verified

A 25.0-mL sample of 0.35 M HCOOH is titrated with 0.20 M KOH. What is the pH of the solution after 25.0 mL of KOH has been added to the acid? K_a = 1.77 × 10^-4

Correct Answer
verified

If the pH of a buffer solution is greater than the pK_a value of the buffer acid, the buffer will have more capacity to neutralize added base than added acid.

Correct Answer
verified

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak base (0.10 mol L^-1) with HCl of the same concentration?

Correct Answer
verified

You need to prepare a buffer solution with a pH of 4.00, using NaF and HF. What ratio of the ratio of [base]/[acid] should be used in making the buffer? For HF, K_a = 7.2 × 10^-4.

Correct Answer
verified

Correct Answer
verified

The solubility of calcium chromate is 1.56 × 10^-3 g/100 mL of solution. What is the K_sp for CaCrO₄?

Correct Answer
verified

A solution is prepared by dissolving 20.0 g of K₂HPO₄ and 25.0 g of KH₂PO₄ in enough water to produce 1.0 L of solution. What is the pH of this buffer? For phosphoric acid (H₃PO₄) , K_a2 = 6.2 × 10^-8.

Correct Answer
verified