Question 1

Equal volumes of the following pairs of solutions are mixed. Which pair will produce a buffer solution?

Accepted Answer

A)  0.10 mol L −1 HCl and 0.05 mol L −1 NaOH
B)  0.10 mol L −1 HCl and 0.15 mol L −1 NH 3
C)  0.10 mol L −1 HCl and 0.05 mol L −1 NH 3
D)  0.10 mol L −1 HCl and 0.20 mol L −1 CH 3COOH
E)  0.10 mol L −1 HCl and 0.20 mol L −1 NaClF) A) and E)
G) C) and E)

Question 2

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

Accepted Answer

A)  [H 2PO 4 −] = 0.50 M, [HPO 4 2−] = 0.50 M
B)  [H 2PO 4 −] = 1.0 M, [HPO 4 2−] = 1.0 M
C)  [H2PO4−] = 1.0 M, [HPO42−] = 0.50 M
D)  [H2PO4−] = 0.50 M, [HPO42−] = 1.0 M
E)  [H 2PO 4 −] = 0.75 M, [HPO 4 2−] = 1.0 MF) B) and E)
G) A) and D)

Question 3

Write the ion product expression for calcium phosphate, Ca3(PO4) 2.

Accepted Answer

A)   3(PO4) 2. 
A)     
B)     
C)     
D)     
E)  None of these choices are correct." class="answers-bank-image d-inline" rel="preload" >
B)   3(PO4) 2. 
A)     
B)     
C)     
D)     
E)  None of these choices are correct." class="answers-bank-image d-inline" rel="preload" >
C)   3(PO4) 2. 
A)     
B)     
C)     
D)     
E)  None of these choices are correct." class="answers-bank-image d-inline" rel="preload" >
D)   3(PO4) 2. 
A)     
B)     
C)     
D)     
E)  None of these choices are correct." class="answers-bank-image d-inline" rel="preload" >
E)  None of these choices are correct.F) A) and B)
G) B) and E)

Question 4

Which, if any, of the following aqueous mixtures would be a buffer system?

Accepted Answer

A)  CH 3COOH, NaH 2PO 4
B)  H 2CO 3, HCO 3 −
C)  H 2PO 4 − , HCO 3 −
D)  HSO 4 − , HSO 3 −
E)  None of these choices are correct.F) A) and D)
G) A) and C)

Question 5

Calculate the solubility of silver oxalate, Ag2C2O4, in pure water. Ksp = 1.0 × 10−11

Accepted Answer

A)  1.4 × 10 −4  M
B)  8.2 × 10 −5  M
C)  5.4 × 10 −5  M
D)  3.2 × 10 −6  M
E)  2.5 × 10 −12  MF) None of the above
G) A) and B)

Question 6

Which of the following acids should be used to prepare a buffer with a pH of 4.5?

Accepted Answer

A)  HOC 6H 4OCOOH, K a = 1.0 × 10 −3
B)  C 6H 4(COOH) 2, K a = 2.9 × 10 −4
C)  CH 3COOH, K a = 1.8 × 10 −5
D)  C 5H 5O 5COOH, K a = 4.0 × 10 −6
E)  HBrO, K a = 2.3 × 10 −9F) B) and C)
G) A) and D)

Question 7

Which one of the following is the best representation of the titration curve that will be obtained in the titration of a weak acid (0.10 mol L−1)  with a strong base of the same concentration? −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) None of the above
G) B) and E)

Question 8

What mass of NaF must be added to 50.0 mL of a 0.500 M HF solution to achieve a pH of 3.25? For HF, Ka = 7.2 × 10−4.

Accepted Answer

A)  1.3 g
B)  0.69 g
C)  6.9 g
D)  23 g
E)  1.5 gF) All of the above
G) D) and E)

Question 9

A 20.0-mL sample of 0.30 M HClO was titrated with 0.30 M NaOH. The following data were collected during the titration. a for HClO? A) 1.1 × 10 −7 B) 3.5 × 10 −8 C) 1.2 × 10 −8 D) 4.9 × 10 −11 E) None of these choices are correct." class="answers-bank-image d-inline" rel="preload" > What is the Ka for HClO?

Accepted Answer

A)  1.1 × 10 −7
B)  3.5 × 10 −8
C)  1.2 × 10 −8
D)  4.9 × 10 −11
E)  None of these choices are correct.F) C) and D)
G) A) and E)

Question 10

A change in pH will significantly affect the solubility of which, if any, of the following compounds?

Accepted Answer

A)  BaF 2
B)  CuCl
C)  CuBr
D)  AgI
E)  None of these choices are correct.F) B) and E)
G) A) and D)

Question 11

The equivalence point in a titration is defined as the point when the indicator changes color.

Accepted Answer

A) True 
 B)False

Question 12

What is the pH of a buffer that consists of 0.20 M NaH2PO4 and 0.40 M Na2HPO4? For NaH2PO4, Ka = 6.2 × 10−8

Accepted Answer

A)  6.51
B)  6.91
C)  7.51
D)  7.90
E)  8.13F) All of the above
G) A) and E)

Question 13

Assuming that the total volume does not change after 0.200 g of KCl is added to 1.0 L of a saturated aqueous solution of AgCl, calculate the number of moles of Ag+ ion in the solution after equilibrium has been reestablished. For AgCl, Ksp = 1.8 × 10−10.

Accepted Answer

A)  1.8 × 10 −10 mol Ag +
B)  9.0 × 10 −10 mol Ag +
C)  9.0 × 10 −9 mol Ag +
D)  6.7 × 10 −8 mol Ag +
E)  1.3 × 10 −5 mol Ag +F) A) and D)
G) A) and C)

Question 14

The solubility of silver chloride __________ when dilute nitric acid is added to it.

Accepted Answer

A)  increases
B)  decreases
C)  does not change
D)  first increases, then decreases
E)  first decreases, then increasesF) B) and E)
G) A) and C)

Question 15

Calculate the solubility of silver chromate, Ag2CrO4, in 0.005 M Na2CrO4. Ksp = 2.6 × 10−12

Accepted Answer

A)  1.4 × 10−4 M
B)  3.4 × 10 −5  M
C)  1.1 × 10 −5  M
D)  1.6 × 10 −6  M
E)  −6  MF) A) and C)
G) C) and E)

Question 16

Calculate the solubility of magnesium sulfate, MgSO4, when placed into a 0.10 M MgCl2 solution. Ksp = 5.9 × 10−3

Accepted Answer

A)  4.2 × 10 −2  M
B)  5.9 × 10 −2  M
C)  7.7 × 10 −2  M
D)  3.5 × 10 −5  M
E)  3.5 × 10 −6  MF) A) and B)
G) B) and E)

Question 17

At the equivalence point in an acid-base titration

Accepted Answer

A)  the [H 3O +] equals the K a of the acid.
B)  the [H 3O +] equals the K a of the indicator.
C)  the amounts of acid and base which have been combined are in their stoichiometric ratio.
D)  the pH is 7.0.
E)  the pH has reached a maximum.F) A) and B)
G) D) and E)

Question 18

Calculate the solubility of silver phosphate, Ag3PO4, in pure water. Ksp = 2.6 × 10−18

Accepted Answer

A)  4.0 × 10 −5  M
B)  1.8 × 10 −5  M
C)  4.0 × 10 −6  M
D)  1.5 × 10 −5  M
E)  −5  MF) A) and E)
G) D) and E)

Question 19

When 20.0 mL of 0.15 M hydrochloric acid is mixed with 20.0 mL of 0.10 M sodium hydroxide, the pH of the resulting solution is

Accepted Answer

A)  0.00.
B)  12.40.
C)  1.60.
D)  0.82.
E)  7.00.F) B) and E)
G) A) and B)

Question 20

Citric acid has an acid dissociation constant of 8.4 × 10−4. It would be most effective for preparation of a buffer with a pH of

Accepted Answer

A)  2.
B)  3.
C)  4.
D)  5.
E)  6.F) B) and D)
G) A) and C)

Exam 19: Ionic Equilibria in Aqueous Systems

Which of the following acids should be used to prepare a buffer with a pH of 4.5?

Correct AnswerverifiedShow Answer

Equal volumes of the following pairs of solutions are mixed. Which pair will produce a buffer solution?

Correct AnswerverifiedShow Answer

Which, if any, of the following aqueous mixtures would be a buffer system?

Correct AnswerverifiedShow Answer

A change in pH will significantly affect the solubility of which, if any, of the following compounds?

Correct AnswerverifiedShow Answer

What is the pH of a buffer that consists of 0.20 M NaH2PO4 and 0.40 M Na2HPO4? For NaH2PO4, Ka = 6.2 × 10−8

Correct AnswerverifiedShow Answer

The solubility of silver chloride __________ when dilute nitric acid is added to it.

Correct AnswerverifiedShow Answer

Citric acid has an acid dissociation constant of 8.4 × 10−4. It would be most effective for preparation of a buffer with a pH of

Correct AnswerverifiedShow Answer

What mass of NaF must be added to 50.0 mL of a 0.500 M HF solution to achieve a pH of 3.25? For HF, Ka = 7.2 × 10−4.

Correct AnswerverifiedShow Answer

Write the ion product expression for calcium phosphate, Ca3(PO4) 2.

Correct AnswerverifiedShow Answer

At the equivalence point in an acid-base titration

Correct AnswerverifiedShow Answer

Assuming that the total volume does not change after 0.200 g of KCl is added to 1.0 L of a saturated aqueous solution of AgCl, calculate the number of moles of Ag+ ion in the solution after equilibrium has been reestablished. For AgCl, Ksp = 1.8 × 10−10.

Correct AnswerverifiedShow Answer

A 20.0-mL sample of 0.30 M HClO was titrated with 0.30 M NaOH. The following data were collected during the titration. What is the Ka for HClO?

Correct AnswerverifiedShow Answer

The equivalence point in a titration is defined as the point when the indicator changes color.

Correct AnswerverifiedShow Answer

Calculate the solubility of magnesium sulfate, MgSO4, when placed into a 0.10 M MgCl2 solution. Ksp = 5.9 × 10−3

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Calculate the solubility of silver chromate, Ag2CrO4, in 0.005 M Na2CrO4. Ksp = 2.6 × 10−12

Correct AnswerverifiedShow Answer

When 20.0 mL of 0.15 M hydrochloric acid is mixed with 20.0 mL of 0.10 M sodium hydroxide, the pH of the resulting solution is

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 acid (0.10 mol L−1) with a strong base of the same concentration?

Correct AnswerverifiedShow Answer

Calculate the solubility of silver oxalate, Ag2C2O4, in pure water. Ksp = 1.0 × 10−11

Correct AnswerverifiedShow Answer

Calculate the solubility of silver phosphate, Ag3PO4, in pure water. Ksp = 2.6 × 10−18

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

What is the pH of a buffer that consists of 0.20 M NaH₂PO₄and 0.40 M Na₂HPO₄? For NaH₂PO₄, K_a = 6.2 × 10⁻⁸

Correct Answer
verified

Correct Answer
verified

Citric acid has an acid dissociation constant of 8.4 × 10⁻⁴. It would be most effective for preparation of a buffer with a pH of

Correct Answer
verified

What mass of NaF must be added to 50.0 mL of a 0.500 M HF solution to achieve a pH of 3.25? For HF, K_a = 7.2 × 10⁻⁴.

Correct Answer
verified

Write the ion product expression for calcium phosphate, Ca₃(PO₄) ₂.

Correct Answer
verified

Correct Answer
verified

Assuming that the total volume does not change after 0.200 g of KCl is added to 1.0 L of a saturated aqueous solution of AgCl, calculate the number of moles of Ag⁺ ion in the solution after equilibrium has been reestablished. For AgCl, K_sp = 1.8 × 10⁻¹⁰.

Correct Answer
verified

A 20.0-mL sample of 0.30 M HClO was titrated with 0.30 M NaOH. The following data were collected during the titration. What is the K_a for HClO?

Correct Answer
verified

Correct Answer
verified

Calculate the solubility of magnesium sulfate, MgSO₄, when placed into a 0.10 M MgCl₂solution. K_sp = 5.9 × 10⁻³

Correct Answer
verified

Correct Answer
verified

Calculate the solubility of silver chromate, Ag₂CrO₄, in 0.005 M Na₂CrO₄. K_sp = 2.6 × 10⁻¹²

Correct Answer
verified

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 acid (0.10 mol L⁻¹) with a strong base of the same concentration?

Correct Answer
verified

Calculate the solubility of silver oxalate, Ag₂C₂O₄, in pure water. K_sp = 1.0 × 10⁻¹¹

Correct Answer
verified

Calculate the solubility of silver phosphate, Ag₃PO₄, in pure water. K_sp = 2.6 × 10⁻¹⁸

Correct Answer
verified