Deck 19: Ionic Equilibria in Aqueous Systems

Question 1

A buffer is prepared by adding 100 mL of 0.50 M sodium hydroxide to 100 mL of 0.75 M propanoic acid.Is this a buffer solution,and if so,what is its pH?

A)It is a buffer,pH > pK_a of propanoic acid.
B)It is a buffer,pH < pK_a of propanoic acid.
C)It is a buffer,pH = pK_a of propanoic acid.
D)It is a buffer,pH = pK_b of sodium propanoate.
E)Since sodium hydroxide is a strong base,this is not a buffer.

Answer 1

It is a buffer,pH > pK_a of propanoic acid.

Question 2

A solution is prepared by adding 500 mL of 0.3 M NaClO to 500 mL of 0.4 M HClO.What is the pH of this solution?

A)The pH will be greater than the pK_a of hypochlorous acid.
B)The pH will be less than the pK_a of hypochlorous acid.
C)The pH will be equal to the pK_a of hypochlorous acid.
D)The pH will equal the pK_b of sodium hypochlorite.
E)The pH will be none of these.

Answer 2

The pH will be less than the pK_a of hypochlorous acid.

Question 3

Which one of the following pairs of 0.100 mol L^-1 solutions,when mixed,will produce a buffer solution?

A)50.mL of aqueous CH₃COOH and 25.mL of aqueous HCl
B)50.mL of aqueous CH₃COOH and 100.mL of aqueous NaOH
C)50.mL of aqueous NaOH and 25.mL of aqueous HCl
D)50.mL of aqueous CH₃COONa and 25.mL of aqueous NaOH
E)50.mL of aqueous CH₃COOH and 25.mL of aqueous CH₃COONa

Answer 3

50.mL of aqueous CH₃COOH and 25.mL of aqueous CH₃COONa

Question 4

A buffer is prepared by adding 0.5 mol of solid sodium hydroxide to 1.0 L of 1.0 M acetic acid (CH₃COOH).What is the pH of the buffer?

A)The pH will be pK_a - 0.30,where pK_a is that of acetic acid.
B)The pH will be greater than the pK_a for acetic acid.
C)The pH will be less than the value in answer a.
D)The pH will be equal to the pK_a for acetic acid.
E)More information is needed to solve the problem.

Question 5

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

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 NH₃
C)0.10 mol L^-1 HCl and 0.05 mol L^-1 NH₃
D)0.10 mol L^-1 HCl and 0.20 mol L^-1 CH₃COOH
E)0.10 mol L^-1 HCl and 0.20 mol L^-1 NaCl

Question 6

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

A)HOC₆H₄OCOOH,K_a = 1.0 $\times$ 10^-3
B)C₆H₄(COOH)₂,K_a = 2.9 $\times$ 10^-4
C)CH₃COOH,K_a = 1.8 $\times$ 10^-5
D)C₅H₅O₅COOH^-2,K_a = 4.0 $\times$ 10^-6
E)HBrO,K_a = 2.3 $\times$ 10^-9

Question 7

A solution is prepared by adding 100 mL of 0.2 M hydrochloric acid to 100 mL of 0.4 M sodium formate.Is this a buffer solution,and if so,what is its pH?

A)It is a buffer,pH > pK_a of formic acid.
B)It is a buffer,pH < pK_a of formic acid.
C)It is a buffer,pH = pK_a of formic acid.
D)It is a buffer,pH = pK_b of sodium formate.
E)Since hydrochloric acid is a strong acid,this is not a buffer.

Question 8

What will be the effect of adding 0.5 mL of 0.1 M NaOH to 100 mL of an acetate buffer in which [CH₃COOH] = [CH₃COO^-] = 0.5 M?

A)The pH will increase slightly.
B)The pH will increase significantly.
C)The pH will decrease slightly.
D)The pH will decrease significantly.
E)Since it is a buffer solution,the pH will not be affected.

Question 9

Citric acid has an acid dissociation constant of 8.4 $\times$ 10^-4.It would be most effective for preparation of a buffer with a pH of

A)2
B)3
C)4
D)5
E)6

Question 10

A buffer is to be prepared by adding solid sodium acetate to 0.10 M CH₃COOH.Which of the following concentrations of sodium acetate will produce the most effective buffer?

A)3.0 M CH₃COONa
B)2.5 M CH₃COONa
C)2.0 M CH₃COONa
D)1.5 M CH₃COONa
E)0.30 M CH₃COONa

Question 11

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

A)[H₂PO₄^-] = 0.50 M,[HPO₄^2-] = 0.50 M
B)[H₂PO₄^-] = 1.0 M,[HPO₄^2-] = 1.0 M
C)[H₂PO₄^-] = 1.0 M,[HPO₄^2-] = 0.50 M
D)[H₂PO₄^-] = 0.50 M,[HPO₄^2-] = 1.0 M
E)[H₂PO₄^-] = 0.75 M,[HPO₄^2-] = 1.0 M

Question 12

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

A)CH₃COOH,NaH₂PO₄
B)H₂CO₃,HCO₃^-
C)H₂PO₄^-,HCO₃^-
D)HSO₄^-,HSO₃^-
E)None of these will be a buffer solution.

Question 13

Which of the following has the highest buffer capacity?

A)0.10 M H₂PO₄^-/0.10 M HPO₄^2-
B)0.50 M H₂PO₄^-/0.10 M HPO₄^2-
C)0.10 M H₂PO₄^-/0.50 M HPO₄^2-
D)0.50 M H₂PO₄^-/0.50 M HPO₄^2-
E)They all have the same buffer capacity.

Question 14

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

A)HCl,NaCl
B)HNO₃,NaNO₃
C)H₃PO₄,H₂PO₄^-
D)H₂SO₄,CH₃COOH
E)NH₃,NaOH

Question 15

Which one of the following aqueous solutions,when mixed with an equal volume of 0.10 mol L^-1 aqueous NH₃,will produce a buffer solution?

A)0.10 mol L^-1 HCl
B)0.20 mol L^-1 HCl
C)0.10 mol L^-1 CH₃COOH
D)0.050 mol L^-1 NaOH
E)0.20 mol L^-1 NH₄Cl

Question 16

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

A)[CH₃COOH] = 0.25 M,[CH₃COO^-] = 0.25 M
B)[CH₃COOH] = 0.75 M,[CH₃COO^-] = 0.75 M
C)[CH₃COOH] = 0.75 M,[CH₃COO^-] = 0.25 M
D)[CH₃COOH] = 0.25 M,[CH₃COO^-] = 0.75 M
E)[CH₃COOH] = 1.00 M,[CH₃COO^-] = 1.00 M

Question 17

A phosphate buffer (H₂PO₄^-/HPO₄^2-)has a pH of 8.3.Which of the following changes will cause the pH to increase?

A)dissolving a small amount of Na₂HPO₄
B)dissolving a small amount of NaH₂PO₄
C)adding a small amount of dilute hydrochloric acid
D)adding a small amount of dilute phosphoric acid
E)making the buffer more concentrated by removing some water

Question 18

What will be the effect of adding 0.5 mL of 0.1 M HCl to 100 mL of a phosphate buffer in which
[H₂PO₄^-] = [HPO₄^2-] = 0.35 M?

A)The pH will increase slightly.
B)The pH will increase significantly.
C)The pH will decrease slightly.
D)The pH will decrease significantly.
E)Since it is a buffer solution,the pH will not be affected.

Question 19

An acetate buffer has a pH of 4.40.Which of the following changes will cause the pH to decrease?

A)dissolving a small amount of solid sodium acetate
B)adding a small amount of dilute hydrochloric acid
C)adding a small amount of dilute sodium hydroxide
D)dissolving a small amount of solid sodium chloride
E)diluting the buffer solution with water

Question 20

What is the pH of a buffer that consists of 0.45 M CH₃COOH and 0.35 M CH₃COONa?
K_a = 1.8 $\times$ 10^-5

A)4.49
B)4.64
C)4.85
D)5.00
E)5.52

Question 21

What is the [H₃O⁺] in a solution that consists of 1.5 M NH₃ and 2.5 NH₄Cl?
K_b = 1.8 $\times$ 10^-5

A)1.1 $\times$ 10^-5 M
B)3.0 $\times$ 10^-6 M
C)3.3 $\times$ 10^-9 M
D)9.3 $\times$ 10^-10 M
E)None of these choices is correct.

Question 22

What is the [H₃O⁺] in a solution that consists of 0.15 M C₂N₂H₈(ethylene diamine)and 0.35 C₂N₂H₉Cl?
K_b = 4.7 $\times$ 10^-4

A)2.0 $\times$ l0^-3 M
B)1.1 $\times$ 10^-3 M
C)6.3 $\times$ 10^-9 M
D)2.1 $\times$ 10^-10 M
E)5.0 $\times$ 10^-11 M

Question 23

What is the [H₃O⁺] in a buffer that consists of 0.30 M HCOOH and 0.20 M HCOONa?
K_a = 1.7 $\times$ 10^-4

A)1.1 $\times$ 10^-4 M
B)2.6 $\times$ 10^-4 M
C)4.3 $\times$ 10^-4 M
D)6.7 $\times$ 10^-5 M
E)None of these choices is correct.

Question 24

What is the [H₃O⁺] in a solution that consists of 1.2 M HClO and 2.3 M NaClO?
K_a = 3.5 $\times$ 10^-8

A)7.8 $\times$ 10^-9 M
B)1.8 $\times$ 10^-8 M
C)6.7 $\times$ 10^-8 M
D)1.6 $\times$ 10^-7 M
E)None of these choices is correct.

Question 25

What is the pK_a for the acid HA if a solution of 0.65 M HA and 0.85 M NaA has a pH of 4.75?

A)< 4.00
B)4.63
C)4.87
D)5.02
E)> 5.50

Question 26

A formic acid buffer containing 0.50 M HCOOH and 0.50 M HCOONa has a pH of 3.77.What will the pH be after 0.010 mol of NaOH has been added to 100.0 mL of the buffer?

A)3.67
B)3.78
C)3.81
D)3.85
E)3.95

Question 27

An acetic acid buffer containing 0.50 M CH₃COOH and 0.50 M CH₃COONa has a pH of 4.74.What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer?

A)4.77
B)4.71
C)4.68
D)4.62
E)None of these choices is correct.

Question 28

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

A)

B)

C)

D)

E)

Question 29

What is the pH of a buffer that consists of 0.20 M NaH₂PO₄ and 0.40 M Na₂HPO₄?
K_a = 6.2 $\times$ 10^-8

A)6.51
B)6.91
C)7.51
D)7.90
E)8.13

Question 30

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

A)3.76
B)3.99
C)4.34
D)4.57
E)5.66

Question 31

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

A)

B)

C)

D)

E)

Question 32

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

A)is greater than 7.0.
B)is equal to 7.0.
C)is less than 7.0.
D)is equal to the pK_a of the acid.
E)is equal to 14.0 - pK_b ,where pK_b is that of the base.

Question 33

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

A)is greater than 7.0.
B)is equal to 7.0.
C)is less than 7.0.
D)is equal to the pK_a of the acid.
E)is equal to the pK_b of the base.

Question 34

The indicator propyl red has K_a = 3.3 $\times$ 10^-6.What would be the approximate pH range over which it would change color?

A)3.5-5.5
B)4.5-6.5
C)5.5-7.5
D)6.5-8.5
E)None of these choices is correct.

Question 35

A buffer is prepared by adding 300.0 mL of 2.0 M NaOH to 500.0 mL of 2.0 M CH₃COOH.What is the pH of this buffer? K_a = 1.8 $\times$ 10^-5

A)4.57
B)4.52
C)4.87
D)4.92
E)4.97

Question 36

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

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 pK_a of the acid.
E)is equal to 3.5.

Question 37

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

A)is greater than 7.0.
B)is equal to 7.0.
C)is less than 7.0.
D)is determined by the sizes of K_a and K_b.
E)is no longer affected by addition of base.

Question 38

A buffer is prepared by adding 150 mL of 1.0 M NaOH to 250 mL of 1.0 M NaH₂PO₄.How many moles of HCl must be added to this buffer solution to change the pH by 0.18 units?

A)0.025 mol HCl
B)0.063 mol HCl
C)0.082 mol HCl
D)0.50 mol HCl
E)1.0 mol HCl

Question 39

At the equivalence point in an acid-base titration

A)the [H₃O⁺] equals the K_a of the acid.
B)the [H₃O⁺] 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.

Question 40

A buffer is prepared by adding 1.00 L of 1.0 M HCl to 750 mL of 1.5 M NaHCOO.What is the pH of this buffer? K_a = 1.7 $\times$ 10^-4

A)2.87
B)3.72
C)3.82
D)3.95
E)4.66

Question 41

A 25.0-mL sample of 1.00 M NH₃ is titrated with 0.15 M HCl.What is the pH of the solution after 15.00 mL of acid have been added to the ammonia solution? K_b = 1.8 $\times$ 10^-5

A)10.26
B)9.30
C)9.21
D)8.30
E)8.21

Question 42

Which of the following indicators would be the best to use when 0.050 M benzoic acid (K_a = 6.6 $\times$ 10^-5)is titrated with 0.05 M NaOH?

A)bromphenol blue,pH range: 3.0-4.5
B)bromcresol green,pH range: 3.8-5.4
C)alizarin,pH range: 5.7-7.2
D)phenol red,pH range: 6.9-8.2
E)phenolphthalein,pH range: 8.0-10.1

Question 43

A 20.0-mL sample of 0.25 M HNO₃ is titrated with 0.15 M Na OH.What is the pH of the solution after 30.0 mL of NaOH have been added to the acid?

A)2.00
B)1.60
C)1.05
D)1.00
E)None of these choices is correct.

Question 44

Write the ion product expression for silver sulfide,Ag₂S.

A)

B)

C)

D)

E)

Question 45

The solubility of aluminum hydroxide in water ______________ when dilute nitric acid is added to it.

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

Question 46

A 10.0-mL sample of 0.75 M CH₃CH₂COOH is titrated with 0.30 M NaOH.What is the pH of the solution after 22.0 mL of NaOH have been added to the acid?
K_a = 1.3 $\times$ 10^-5

A)5.75
B)4.94
C)4.83
D)4.02
E)3.95

Question 47

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

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

Question 48

A 20.0-mL sample of 0.30 M HBr is titrated with 0.15 M NaOH.What is the pH of the solution after 40.3 mL of NaOH have been added to the acid?

A)2.95
B)3.13
C)10.87
D)11.05
E)13.14

Question 49

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

A)2.4 $\times$ 10^-4
B)1.5 $\times$ 10^-5
C)7.6 $\times$ 10^-6
D)1.0 $\times$ 10^-8
E)< 1.0 $\times$ 10^-8

Question 50

The solubility of lead(II)chloride is 0.45 g/100 mL of solution.What is the K_sp of PbCl₂?

A)4.9 $\times$ 10^-2
B)1.7 $\times$ 10^-5
C)8.5 $\times$ 10^-6
D)4.2 $\times$ 10^-6
E) < 1.0 $\times$ 10^-6

Question 51

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 $\times$ 10^-4

A)11.08
B)10.88
C)10.74
D)10.55
E)10.49

Question 52

The solubility of silver chromate is 0.0287 g/1.0 L of solution.What is the K_sp for Ag₂CrO₄?

A)9.5 $\times$ 10^-5
B)2.4 $\times$ 10^-5
C)2.6 $\times$ 10^-12
D)6.5 $\times$ 10^-13
E)< 1.0 $\times$ 10^-13

Question 53

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

A)

B)

C)

D)

E)None of these is the correct ion product expression.

Question 54

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

A)BaF₂
B)CuCl
C)CuBr
D)AgI
E)None of the solubilities will be significantly affected.

Question 55

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?

A)1.1 $\times$ 10^-7
B)3.5 $\times$ 10^-8
C)1.2 $\times$ 10^-8
D)4.9 $\times$ 10^-11
E)None of these choices is correct.

Question 56

What volume of 0.500 M H₂SO₄ is needed to react completely with 20.0 mL of 0.400 M LiOH?

A)4.00 mL
B)8.00 mL
C)12.5 mL
D)16.0 mL
E)32.0 mL

Question 57

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 $\times$ 10^-4

A)4.00
B)3.88
C)3.63
D)3.51
E)3.47

Question 58

A 50.0-mL sample of 0.50 M HCl is titrated with 0.50 M NaOH.What is the pH of the solution after 28.0 mL of NaOH have been added to the acid?

A)0.85
B)0.75
C)0.66
D)0.49
E)3.8

Question 59

Write the ion product expression for magnesium fluoride,MgF₂.

A)

B)

C)

D)

E)

Question 60

A 35.0-mL sample of 0.20 M LiOH is titrated with 0.25 M HCl.What is the pH of the solution after 23.0 mL of HCl have been added to the base?

A)1.26
B)1.67
C)12.33
D)12.74
E)13.03

Question 61

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

A)PbI₂,K_sp = 7.9 $\times$ 10^-9
B)BaF₂,K_sp = 1.5 $\times$ 10^-6
C)Ca(OH)₂,K_sp = 6.5 $\times$ 10^-6
D)Zn(IO₃)₂,K_sp = 3.9 $\times$ 10^-6
E)Ag₂SO₄,K_sp = 1.5 $\times$ 10^-5

Question 62

Calculate the solubility of strontium fluoride,SrF₂,in pure water.K_sp = 2.6 $\times$ 10^-9

A)1.4 $\times$ 10^-3 M
B)3.4 $\times$ 10^-4 M
C)8.7 $\times$ 10^-4 M
D)5.l $\times$ 10^-5 M
E)< 1.0 $\times$ 10^-5 M

Question 63

The concentration of the complex ion in each of following solutions is 1.00 M.In which of the solutions will the concentration of the uncomplexed metal ion be the greatest?
Hg(CN)₄^2- K_f = 9.3 $\times$ 10³⁸
Be(OH)₄^2- K_f = 4.0 $\times$ 10¹⁸
Zn(OH)₄^2- K_f = 3.0 $\times$ 10¹⁵
Cu(NH₃)₄²⁺ K_f = 5.6 $\times$ 10¹¹
CdI₄^2- K_f = 1.0 $\times$ 10⁶

A)Hg²⁺
B)Be²⁺
C)Zn²⁺
D)Cu²⁺
E)Cd²⁺

Question 64

The lab technician Anna Lytic adds 2.20 mol KOH to 1.00 L of 0.5 M Al(NO₃)₃.What is the concentration of aluminum ions after the aluminum nitrate has reacted with the potassium hydroxide?
K_f = 3.0 $\times$ 10³³ for Al(OH)₄^-

A)1.8 $\times$ 10^-7 M
B)9.l $\times$ 10^-18 M
C)1.0 $\times$ 10^-31 M
D)3.3 $\times$ 10^-34 M
E)7.l $\times$ 10^-36 M

Question 65

The solubility of magnesium phosphate is 2.27 $\times$ 10^-3 g/1.0 L of solution.What is the K_sp for Mg₃(PO₄)₂?

A)6.5 $\times$ 10^-12
B)6.0 $\times$ 10^-14
C)5.2 $\times$ 10^-24
D)4.8 $\times$ 10^-26
E)1.0 $\times$ 10^-26

Question 66

A lab technician adds 0.015 mol of KOH to 1.00 L of 0.0010 M Ca(NO₃)₂.K_sp = 6.5 $\times$ 10^-6 for Ca(OH)₂.Which of the following statements is correct?

A)Calcium hydroxide precipitates until the solution is saturated.
B)The solution is unsaturated and no precipitate forms.
C)The concentration of calcium ions is reduced by the addition of the hydroxide ions.
D)One must know K_sp for calcium nitrate to make meaningful predictions on this system.
E)The presence of KOH will raise the solubility of Ca(NO₃)₂.

Question 67

Calculate the solubility of silver chromate,Ag₂CrO₄,in 0.005 M Na₂CrO₄.K_sp = 2.6 $\times$ 10^-12

A)1.4 $\times$ 10^-4 M
B)3.4 $\times$ 10^-5 M
C)1.1 $\times$ 10^-5 M
D)1.6 $\times$ 10^-6 M
E)< 1.0 $\times$ 10^-6 M

Question 68

A solution is prepared by adding 4.50 mol of sodium hydroxide to 1.00 L of 1.00 M Co(NO₃)₂.What is the equilibrium concentration of cobalt ions?
K_f = 5.0 $\times$ 10⁹ for Co(OH)₄^2-

A)1.1 $\times$ 10^-2 M
B)1.4 $\times$ 10^-5 M
C)3.2 $\times$ 10^-9 M
D)2.0 $\times$ 10^-10 M
E)4.9 $\times$ 10^-13 M

Question 69

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

A)0.60 M
B)0.52 M
C)0.37 M
D)0.32 M
E)0.24 M

Question 70

A lab technician adds 0.20 mol of NaF to 1.00 L of 0.35 M cadmium nitrate,Cd(NO₃)₂.Which of the following statements is correct? K_sp = 6.44 $\times$ 10^-3 for CdF₂

A)Cadmium fluoride precipitates until the solution is saturated.
B)The solution is unsaturated and no precipitate forms.
C)The solubility of cadmium fluoride is increased by the presence of additional fluoride ions.
D)One must know K_sp for cadmium nitrate to make meaningful predictions on this system.
E)The presence of NaF will raise the solubility of Cd(NO₃)₂.

Question 71

Calculate the solubility of silver oxalate,Ag₂C₂O₄,in pure water.K_sp = 1.0 $\times$ 10^-11

A)1.4 $\times$ 10^-4 M
B)8.2 $\times$ 10^-5 M
C)5.4 $\times$ 10^-5 M
D)3.2 $\times$ 10^-6 M
E)2.5 $\times$ 10^-12 M

Question 72

Calculate the solubility of barium carbonate,BaCO₃,in pure water.K_sp = 2.0 $\times$ 10^-9

A)1.3 $\times$ 10^-3 M
B)3.2 $\times$ 10^-5 M
C)2.2 $\times$ 10^-5 M
D)4.5 $\times$ 10^-5 M
E)4.0 $\times$ 10^-18 M

Question 73

Consider the dissolution of MnS in water (K_sp = 3.0 $\times$ 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 pK_a of H₂S is needed before a reliable prediction can be made.

Question 74

Calculate the solubility of silver phosphate,Ag₃PO₄,in pure water.K_sp = 2.6 $\times$ 10^-18

A)4.0 $\times$ 10^-5 M
B)1.8 $\times$ 10^-5 M
C)4.0 $\times$ 10^-6 M
D)1.5 $\times$ 10^-6 M
E)< 1.0 $\times$ 10^-6 M

Question 75

What is the pH of 375 mL of solution containing 0.150 mol of propenoic acid (HA)and 0.250 mol of sodium propenoate (NaA)? (K_a for propenoic acid is 5.52 $\times$ 10^-5. )

Question 76

What is the maximum amount of sodium sulfate that can be added to 1.00 L of 0.0020 M Ca(NO₃)₂ before precipitation of calcium sulfate begins? K_sp = 2.4 $\times$ 10^-5 for calcium sulfate

A)1.2 $\times$ 10^-2 mol
B)4.9 $\times$ 10^-3 mol
C)3.5 $\times$ 10^-3 mol
D)1.2 $\times$ 10^-5 mol
E)4.8 $\times$ 10^-8 mol

Question 77

Calculate the solubility of lead(II)iodide,PbI₂,in 0.025 M KI.K_sp = 7.9 $\times$ 10^-9

A)4.5 $\times$ 10^-2 M
B)2.8 $\times$ 10^-2 M
C)8.9 $\times$ 10^-5 M
D)5.0 $\times$ 10^-5 M
E)1.3 $\times$ 10^-5 M

Question 78

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

A)MgCO₃,K_sp = 3.5 $\times$ 10^-8
B)NiCO₃,K_sp = 1.3 $\times$ 10^-7
C)AgIO₃,K_sp = 3.1 $\times$ 10^-8
D)CuBr,K_sp = 5.0 $\times$ 10^-9
E)AgCN,K_sp = 2.2 $\times$ 10^-16

Question 79

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

A)Ba(IO₃)₂,K_sp = 1.5 $\times$ 10^-9
B)PbF₂,K_sp = 3.6 $\times$ 10^-8
C)SrSO₄,K_sp = 3.2 $\times$ 10^-7
D)CuCl,K_sp = 1.9 $\times$ 10^-7
E)CdS,K_sp = 1.0 $\times$ 10^-24

Question 80

Calculate the solubility of magnesium sulfate,MgSO₄,when placed into a 0.10 M MgCl₂ solution.
K_sp = 5.9 $\times$ 10^-3

A)4.2 $\times$ 10^-2 M
B)5.9 $\times$ 10^-2 M
C)7.7 $\times$ 10^-2 M
D)3.5 $\times$ 10^-5 M
E)3.5 $\times$ 10^-6 M