Chapter 16: Solubility and Complex Ion Equilibria
1. The molar solubility of PbI2 is 1.52 10–3 M. Calculate the value of Ksp for PbI2.
A)
3.51 10−9
B)
4.62 10−6
C)
1.40 10−8
D)
1.52 10−3
E)
none of these
2. The concentration of OH– in a saturated solution of Mg(OH)2 is 3.63 10–4 M. The Ksp of
Mg(OH)2 is
A)
6.6 10−8
B)
4.8 10−11
C)
1.3 10−7
D)
3.6 10−4
E)
2.4 10−11
3. The solubility of CaSO4 in pure water at 0oC is 1.14 gram(s) per liter. The value of the
solubility product is
A)
8.37 10−3
B)
1.14 10−3
C)
9.15 10−2
D)
7.01 10−5
E)
none of these
4. It is observed that 7.50 mmol of BaF2 will dissolve in 1.0 L of water. Use these data to
calculate the value of Ksp for barium fluoride.
A)
1.1 10−4
B)
4.2 10−7
C)
1.7 10−6
D)
2.2 10−4
E)
5.6 10−5
5. The solubility in mol/L of Ag2CrO4 is 1.8 10–4 M. Calculate the Ksp for this compound.
A)
6.5 10−8
B)
1.8 10−4
C)
2.3 10−11
D)
5.8 10−12
E)
3.6 10−4
6. The solubility of Cd(OH)2 in water is 1.67 10–5 mol/L. The Ksp value for Cd(OH)2 is
A)
1.86 10−14
B)
4.66 10−15
C)
5.58 10−10
D)
1.67 10−5
E)
none of these
7. The solubility of silver phosphate, Ag3PO4, at 25°C is 1.60 10–5 mol/L. What is the Ksp for
the silver phosphate at 25°C?
A)
1.11 10−13
B)
1.77 10−18
C)
7.68 10−10
D)
6.55 10−20
E)
none of these
8. The solubility of an unknown salt, M3Z2, at 25°C is
3.1 10−7
mol/L. What is the Ksp for
M3Z2 at 25°C?
A)
4.2 10−23
B)
1.0 10−24
C)
7.7 10−32
D)
3.1 10−31
E)
none of these
9. The solubility of an unknown salt, MZ2, at 25°C is
3.9 10−4
mol/L. What is the Ksp for
MZ2 at 25°C?
A)
3.8 10−9
B)
1.5 10−7
C)
1.6 10−9
6.1 10−7
E)
none of these
10. The solubility of an unknown salt, MZ3, at 25°C is
3.1 10−5
mol/L. What is the Ksp for
MZ3 at 25°C?
A)
5.9 10−10
B)
2.5 10−17
C)
8.0 10−13
D)
1.2 10−13
E)
none of these
11. Barium carbonate has a measured solubility of 4.03 10–5 at 25°C. Determine the Ksp.
A)
4.03 10−5
B)
8.06 10−5
C)
6.35 10−3
D)
2.62 10−13
E)
1.62 10−9
12. A 300.0-mL saturated solution of copper(II) peroidate, Cu(IO4)2, contains 0.30 grams of
dissolved salt. Determine the Ksp.
A)
1.0 10−5
B)
2.0 10−5
C)
2.2 10−3
D)
4.5 10−8
E)
1.2 10−9
13. The in a saturated solution of is 5.93 10–3 M. Calculate the Ksp for
.
A)
4.12 10−10
B)
3.71 10−9
C)
2.09 10−7
1.98 10−3
E)
none of these
14. The correct mathematical expression for finding the molar solubility (s) of Sn(OH)2 is:
A)
2s2 = Ksp
B)
2s3 = Ksp
C)
108s5 = Ksp
D)
4s3 = Ksp
E)
8s3 = Ksp
15. Find the solubility (in mol/L) of lead(II) chloride, PbCl2, at 25°C. Ksp = 1.59 10–5.
A)
1.58 10−2
B)
2.51 10−2
C)
6.28 10−17
D)
1.99 10−3
E)
2.00 10−2
16. Calculate the concentration of chromate ion, CrO42–, in a saturated solution of CaCrO4
(Ksp = 7.08 10–4).
A)
2.66 10−2
M
B)
1.42 10−3
M
C)
7.08 10−4
M
D)
5.01 10−7
M
E)
3.54 10−4
M
17. Calculate the concentration of the silver ion in a saturated solution of silver chloride, AgCl
(Ksp = 1.57 10–10).
A)
1.57 10−10
B)
1.25 10−5
C)
2.46 10−20
D)
3.14 10−10
E)
none of these
18. Silver chromate, Ag2CrO4, has a Ksp of 8.96 10–12. Calculate the solubility in mol/L of
silver chromate.
A)
1.31 10−4
M
B)
1.65 10−4
M
C)
2.25 10−12
M
D)
2.08 10−4
M
E)
1.50 10−6
M
19. An unknown salt, M2Z, has a Ksp of
3.3 10−9
. Calculate the solubility in mol/L of M2Z.
A)
2.9 10−5
M
B)
5.7 10−5
M
C)
9.4 10−4
M
D)
3.7 10−4
M
E)
none of the above
20. An unknown salt, M3Z, has a Ksp of
1.2 10−17
. Calculate the solubility in mol/L of M3Z.
A)
2.6 10−5
M
B)
3.5 10−9
M
C)
1.4 10−6
M
D)
2.2 10−6
M
E)
none of the above
21. Calculate the concentration of Al3+ in a saturated aqueous solution of Al(OH)3
(Ksp = 2.2 10–32).
A)
7.0 10−9
B)
2.0 10−34
C)
1.2 10−8
D)
8.1 10−34
E)
5.3 10−9
22. In a solution prepared by adding excess PbI2 (Ksp = 1.44 10–8) to water, the [I–] at
equilibrium is:
A)
1.53 10−3
mol/L
B)
7.20 10−9
mol/L
C)
1.20 10−4
mol/L
D)
9.33 10−26
mol/L
E)
3.07 10−3
mol/L
23. The solubility of silver phosphate, Ag3PO4, at 25°C is 1.55 10–5 mol/L. Determine the
concentration of the Ag+ ion in a saturated solution.
A)
1.55 10−5
M
B)
5.17 10−6
M
C)
4.65 10−5
M
D)
1.94 105
M
E)
3.72 10−15
M
24. Which of the following compounds has the lowest solubility in mol/L in water at 25°C?
A)
Ag3PO4 Ksp = 1.8 10–18
B)
Sn(OH)2 Ksp = 3 10–27
C)
CdS Ksp = 1.0 10–28
D)
CaSO4 Ksp = 6.1 10–5
E)
Al(OH)3 Ksp = 2 10–33
25. Solubility Products (Ksp)
BaSO4
1.5 10–9
CoS
5.0 10–22
PbSO4
1.3 10–8
AgBr
5.0 10–13
BaCO3
1.6 10–9
Which of the following compounds is the most soluble (in moles/liter)?
A)
BaSO4
B)
CoS
C)
PbSO4
D)
AgBr
E)
BaCO3
26. Which of the following compounds has the lowest solubility in mol/L in water?
A)
Al(OH)3 Ksp = 2 10–32
B)
CdS Ksp = 1.0 10–28
C)
PbSO4 Ksp = 1.3 10–8
D)
Sn(OH)2 Ksp = 3 10–27
E)
MgC2O4 Ksp = 8.6 10–5
27. Which of the following salts shows the lowest solubility in water? (Ksp values:
Ag2S = 1.6 10–49; Bi2S3 = 1.0 10–72; HgS = 1.6 10–54; Mg(OH)2 = 8.9 10–12;
MnS = 2.3 10–13)
A)
Bi2S3
B)
Ag2S
C)
MnS
D)
HgS
E)
Mg(OH)2
28. How many moles of Fe(OH)2 [Ksp = 1.8 10–15] will dissolve in 1.0 liter of water buffered
at pH = 10.37?
A)
3.3 10−8
B)
2.3 10−4
C)
5.5 10−8
D)
3.1 107
E)
7.7 10−12
29. The molar solubility of BaCO3 (Ksp = 1.6 10–9) in 0.10 M BaCl2 solution is:
A)
1.6 10–10
B)
4.0 10–5
C)
7.4 10–4
D)
0.10
E)
none of these
30. The Ksp of AgI is 1.5 10–16. Calculate the solubility in mol/L of AgI in a 0.30 M NaI
solution.
A)
4.5 10−17
B)
0.30
C)
1.5 10−16
D)
1.2 10−8
E)
5.0 10−16
31. The molar solubility of AgCl (Ksp = 1.6 10–10) in 0.0035 M sodium chloride at 25°C is:
A)
0.0035
B)
5.6 10−13
C)
4.6 10−8
D)
1.6 10−10
E)
none of these
32. The Ksp of PbSO4 is 1.3 10–8. Calculate the solubility (in mol/L) of PbSO4 in a 0.0037 M
solution of Na2SO4.
A)
4.8 10−11
M
B)
1.2 10−11
M
C)
3.5 10−6
M
D)
1.3 10−8
M
E)
1.9 10−3
M
33. The Ksp for PbF2 is 4.0 10–8. If a 0.040 M NaF solution is saturated with PbF2, what is the
[Pb2+] in the solution?
A)
1.0 10−6
M
B)
6.4 10−11
M
C)
6.3 10−4
M
D)
2.5 10−5
M
E)
1.6 10−9
M
34. The Ksp of an unknown salt, MZ2, is . Calculate the solubility (in mol/L) of MZ2
in a 0.0230 M solution of CaZ2.
A)
1.7 10−5
M
B)
1.4 10−7
M
C)
4.1 10−13
M
D)
3.6 10−11
M
E)
9.0 10−12
M
35. The solubility of La(IO3)3 in a 0.42 M KIO3 solution is
5.6 10−12
mol/L. Calculate the Ksp
for La(IO3)3.
A)
1.1 10−11
B)
7.6 10−11
C)
4.2 10−13
D)
7.4 10−35
E)
none of these
36. The solubility of an unknown salt, M2Z, in a 0.0768 M CaZ solution is mol/L.
Calculate the Ksp for M2Z.
A)
9.6 10−20
B)
2.4 10−20
C)
1.7 10−12
D)
7.0 10−28
E)
none of these
37. Chromate ion is added to a saturated solution of Ag2CrO4 to reach 0.78 M CrO42–. Calculate
the final concentration of silver ion at equilibrium (Ksp for Ag2CrO4 is 9.0 10–12).
A)
1.7 10−6
M
B)
3.4 10−6
M
C)
4.8 10−6
M
D)
5.8 10−12
M
E)
2.4 10−6
M
38. Calculate the solubility of Ag2CrO4 (Ksp = 9.0 10–12) in a 0.049 M AgNO3 solution.
A)
1.8 10−10
mol/L
B)
9.2 10−11
mol/L
C)
3.7 10−9
mol/L
D)
1.9 10−9
mol/L
E)
none of these
39. The solubility of Mg(OH)2 (Ksp = 8.9 10–12) in 1.0 L of a solution buffered (with large
capacity) at pH 9.73 is:
A)
2.6 108
moles
B)
3.1 10−3
moles
C)
1.7 10−7
moles
D)
5.4 10−5
moles
E)
none of these
40. Calculate the solubility of Ca3(PO4)2 (Ksp = 1.3 10–32) in a 0.048 M Ca(NO3)2 solution.
A)
5.4 10−15
mol/L
B)
1.1 10−14
mol/L
C)
2.6 10−16
mol/L
D)
2.9 10−29
mol/L
E)
none of these
41. Calculate the solubility of Cu(OH)2 in a solution buffered at pH = 7.59. (Ksp = 1.6 10–19)
A)
3.9 10−7
M
B)
4.1 10−13
M
C)
1.1 10−6
M
D)
1.5 10−13
M
E)
none of these
42. How many moles of CaF2 will dissolve in 3.0 liters of 0.089 M NaF solution? (Ksp for
CaF2 = 4.0 10–11)
A)
5.0 10−9
B)
1.5 10−10
C)
1.5 10−8
D)
1.7 10−9
E)
none of these
43. The solubility in mol/L of M(OH)2 in 0.053 M KOH is 1.0 10–5 mol/L. What is the Ksp for
M(OH)2?
A)
2.8 10−8
B)
5.3 10−7
C)
2.8 10−3
D)
4.0 10−15
E)
2.3 10−6
44. The two salts AgX and AgY exhibit very similar solubilities in water. It is known that the
salt AgX is much more soluble in acid than is AgY. What can be said about the relative
strengths of the acids HX and HY?
A)
Nothing.
B)
HY is stronger than HX.
C)
HX is stronger than HY.
D)
The acids are weak acids and have equal values for Ka.
E)
Both acids are strong.
45. You have two salts, AgX and AgY, with very similar Ksp values. You know that Ka for HX
is much greater than Ka for HY. Which salt is more soluble in acidic solution?
A)
AgX
B)
AgY
C)
They are equally soluble in acidic solution.
D)
Cannot be determined by the information given.
E)
None of these (A-D).
46. The solubility of AgCl in water is _____ the solubility of AgCl in strong acid at the same
temperature.
A)
greater than
B)
less than
C)
about the same as
D)
cannot be determined
E)
much different from
47. Which of the following solid salts is more soluble in 1.0 M H+ than in pure water?
A)
NaCl
B)
CaCO3
C)
KCl
D)
AgCl
E)
KNO3
48. Which of the following solid salts is more soluble in 1.0 M H+ than in pure water?
A)
NaCl
B)
KCl
C)
FePO4
D)
AgCl
E)
KNO3
49. Given the following Ksp values, which statement about solubility in mol/L in water is
correct?
Ksp
Ksp
PbCrO4
2.0 10–16
Pb(OH)2
1.2 10–15
Zn(OH)2
4.5 10–17
MnS
2.3 10–13
A)
PbCrO4, Zn(OH)2, and Pb(OH)2 have equal solubilities in water.
B)
PbCrO4 has the lowest solubility in water.
C)
The solubility of MnS in water will not be pH dependent.
D)
MnS has the highest molar solubility in water.
E)
A saturated PbCrO4 solution will have a higher [Pb2+] than a saturated Pb(OH)2
solution.
50. The best explanation for the dissolution of ZnS in dilute HCl is that:
A)
The zinc ion is amphoteric.
B)
The sulfide-ion concentration is decreased by the formation of H2S.
C)
the sulfide-ion concentration is decreased by oxidation to sulfur.
D)
the zinc-ion concentration is decreased by the formation of a chloro complex.
E)
The solubility product of ZnCl2 is less than that of ZnS.
51. What is the best way to ensure complete precipitation of SnS from a saturated H2S solution?
A)
Add more H2S.
B)
Add a strong acid.
C)
Add a weak acid.
D)
Add a strong base.
E)
Add a weak base.
52. The Ksp of Al(OH)3 is 2 10–32. At what pH will a 0.5 M Al3+ solution begin to show
precipitation of Al(OH)3?
A)
3.5
B)
10.5
C)
1.0
D)
6.0
E)
3.1
53. You have a solution consisting of 0.10 M Cl– and 0.10 M CrO42–. You add 0.10 M silver
nitrate dropwise to this solution. Given that the Ksp for Ag2CrO4 is 9.0 10–12, and that for
AgCl is 1.6 10–10, which of the following will precipitate first?
A)
silver chloride
B)
silver chromate
C)
silver nitrate
D)
cannot be determined by the information given
E)
none of these
The following questions refer to the following system: 3.5 102 mL of 3.2 M Pb(NO3)2 and
2.0 102 mL of 0.020 M NaCl are added together. Ksp for the lead chloride is 1.6 10–5.