Deck 16: Solubility and Complex Ion Equilibria

Question 1

The solubility of an unknown salt,MZ_2, at 25°C is mol/L.What is the K_sp for MZ₂ at 25°C?

A)
B)
C)
D)
E)none of these

Answer 1

none of these

Question 2

Calculate the concentration of chromate ion,CrO₄^2-,in a saturated solution of CaCrO₄ (K_sp = 7.08 $\times$ 10^-4).

A) M
B) M
C) M
D) M
E) M

Answer 2

M

Question 3

The solubility of silver phosphate,Ag₃PO_4, at 25°C is 1.60 $\times$ 10^-5 mol/L.What is the K_sp for the silver phosphate at 25°C?

A)
B)
C)
D)
E)none of these

Answer 3

Question 4

Silver chromate,Ag₂CrO₄,has a K_sp of 8.96 $\times$ 10^-12.Calculate the solubility in mol/L of silver chromate.

A) M
B) M
C) M
D) M
E) M

Question 5

The solubility of Cd(OH)₂ in water is 1.67 $\times$ 10^-5 mol/L.The K_sp value for Cd(OH)₂ is

A)
B)
C)
D)
E)none of these

Question 6

The molar solubility of PbI₂ is 1.52 $\times$ 10^-3 M.Calculate the value of K_sp for PbI₂.

A)
B)
C)
D)
E)none of these

Question 7

The in a saturated solution of is 5.93 $\times$ 10^-3 M.Calculate the K_sp for .

A)
B)
C)
D)
E)none of these

Question 8

The correct mathematical expression for finding the molar solubility (s)of Sn(OH)₂ is:

A)2s² = K_sp
B)2s³ = K_sp
C)108s⁵ = K_sp
D)4s³ = K_sp
E)8s³ = K_sp

Question 9

A 300.0-mL saturated solution of copper(II)peroidate,Cu(IO₄)₂,contains 0.30 grams of dissolved salt.Determine the K_sp.

A)
B)
C)
D)
E)

Question 10

An unknown salt,M₂Z,has a K_sp of .Calculate the solubility in mol/L of M₂Z.

A) M
B) M
C) M
D) M
E)none of the above

Question 11

Calculate the concentration of the silver ion in a saturated solution of silver chloride,AgCl (K_sp = 1.57 $\times$ 10^-10).

A)
B)
C)
D)
E)none of these

Question 12

The solubility of an unknown salt,M₃Z_2, at 25°C is mol/L.What is the K_sp for M₃Z₂ at 25°C?

A)
B)
C)
D)
E)none of these

Question 13

The solubility of an unknown salt,MZ_3, at 25°C is mol/L.What is the K_sp for MZ₃ at 25°C?

A)
B)
C)
D)
E)none of these

Question 14

The solubility in mol/L of Ag₂CrO₄ is 1.8 $\times$ 10^-4 M.Calculate the K_sp for this compound.

A)
B)
C)
D)
E)

Question 15

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 K_sp for barium fluoride.

A)
B)
C)
D)
E)

Question 16

The solubility of CaSO₄ in pure water at 0^oC is 1.14 gram(s)per liter.The value of the solubility product is

A)
B)
C)
D)
E)none of these

Question 17

An unknown salt,M₃Z,has a K_sp of .Calculate the solubility in mol/L of M₃Z.

A) M
B) M
C) M
D) M
E)none of the above

Question 18

The concentration of OH^- in a saturated solution of Mg(OH)₂ is 3.63 $\times$ 10^-4 M.The K_sp of Mg(OH)₂ is

A)
B)
C)
D)
E)

Question 19

Barium carbonate has a measured solubility of 4.03 $\times$ 10^-5 at 25°C.Determine the K_sp.

A)
B)
C)
D)
E)

Question 20

Find the solubility (in mol/L)of lead(II)chloride,PbCl₂,at 25°C.K_sp = 1.59 $\times$ 10^-5.

A)
B)
C)
D)
E)

Question 21

Calculate the solubility of Ag₂CrO₄ (K_sp = 9.0 $\times$ 10^-12)in a 0.049 M AgNO₃ solution.

A) mol/L
B) mol/L
C) mol/L
D) mol/L
E)none of these

Question 22

Chromate ion is added to a saturated solution of Ag₂CrO₄ to reach 0.78 M CrO₄^2-.Calculate the final concentration of silver ion at equilibrium (K_sp for Ag₂CrO₄ is 9.0 $\times$ 10^-12).

A) M
B) M
C) M
D) M
E) M

Question 23

The solubility of La(IO₃)₃ in a 0.42 M KIO₃ solution is mol/L.Calculate the K_sp for La(IO₃)₃.

A)
B)
C)
D)
E)none of these

Question 24

Solubility Products (K_sp)
Which of the following compounds is the most soluble (in moles/liter)?

A)BaSO₄
B)CoS
C)PbSO₄
D)AgBr
E)BaCO₃

Question 25

Which of the following salts shows the lowest solubility in water? (K_sp values: Ag₂S = 1.6 $\times$ 10^-49;Bi₂S₃ = 1.0 $\times$ 10^-72;HgS = 1.6 $\times$ 10^-54;Mg(OH)₂ = 8.9 $\times$ 10^-12;MnS = 2.3 $\times$ 10^-13)

A)Bi₂S₃
B)Ag₂S
C)MnS
D)HgS
E)Mg(OH)₂

Question 26

The K_sp of an unknown salt,MZ₂,is .Calculate the solubility (in mol/L)of MZ₂ in a 0.0230 M solution of CaZ₂.

A) M
B) M
C) M
D) M
E) M

Question 27

Which of the following compounds has the lowest solubility in mol/L in water at 25°C?

A)Ag₃PO₄ K_sp = 1.8 $\times$ 10^-18
B)Sn(OH)₂ K_sp = 3 $\times$ 10^-27
C)CdS K_sp = 1.0 $\times$ 10^-28
D)CaSO₄ K_sp = 6.1 $\times$ 10^-5
E)Al(OH)₃ K_sp = 2 $\times$ 10^-33

Question 28

The solubility of an unknown salt,M₂Z,in a 0.0768 M CaZ solution is mol/L.Calculate the K_sp for M₂Z.

A)
B)
C)
D)
E)none of these

Question 29

The solubility of silver phosphate,Ag₃PO₄,at 25°C is 1.55 $\times$ 10^-5 mol/L.Determine the concentration of the Ag⁺ ion in a saturated solution.

A) M
B) M
C) M
D) M
E) M

Question 30

Calculate the solubility of Ca₃(PO₄)₂ (K_sp = 1.3 $\times$ 10^-32)in a 0.048 M Ca(NO₃)₂ solution.

A) mol/L
B) mol/L
C) mol/L
D) mol/L
E)none of these

Question 31

The K_sp of PbSO₄ is 1.3 $\times$ 10^-8.Calculate the solubility (in mol/L)of PbSO₄ in a 0.0037 M solution of Na₂SO₄.

A) M
B) M
C) M
D) M
E) M

Question 32

Which of the following compounds has the lowest solubility in mol/L in water?

A)Al(OH)₃ K_sp = 2 $\times$ 10^-32
B)CdS K_sp = 1.0 $\times$ 10^-28
C)PbSO₄ K_sp = 1.3 $\times$ 10^-8
D)Sn(OH)₂ K_sp = 3 $\times$ 10^-27
E)MgC₂O₄ K_sp = 8.6 $\times$ 10^-5

Question 33

How many moles of Fe(OH)₂ [K_sp = 1.8 $\times$ 10^-15] will dissolve in 1.0 liter of water buffered at pH = 10.37?

A)
B)
C)
D)
E)

Question 34

The solubility of Mg(OH)₂ (K_sp = 8.9 $\times$ 10^-12)in 1.0 L of a solution buffered (with large capacity)at pH 9.73 is:

A) moles
B) moles
C) moles
D) moles
E)none of these

Question 35

The molar solubility of AgCl (K_sp = 1.6 $\times$ 10^-10)in 0.0035 M sodium chloride at 25°C is:

A)0.0035
B)
C)
D)
E)none of these

Question 36

In a solution prepared by adding excess PbI₂ (K_sp = 1.44 $\times$ 10^-8)to water,the [I^-] at equilibrium is:

A) mol/L
B) mol/L
C) mol/L
D) mol/L
E) mol/L

Question 37

The K_sp for PbF₂ is 4.0 $\times$ 10^-8.If a 0.040 M NaF solution is saturated with PbF₂,what is the [Pb²⁺] in the solution?

A) M
B) M
C) M
D) M
E) M

Question 38

Calculate the concentration of Al³⁺ in a saturated aqueous solution of Al(OH)₃ (K_sp = 2.2 $\times$ 10^-32).

A)
B)
C)
D)
E)

Question 39

The molar solubility of BaCO₃ (K_sp = 1.6 $\times$ 10^-9)in 0.10 M BaCl₂ solution is:

A)1.6 $\times$ 10^-10
B)4.0 $\times$ 10^-5
C)7.4 $\times$ 10^-4
D)0.10
E)none of these

Question 40

The K_sp of AgI is 1.5 $\times$ 10^-16.Calculate the solubility in mol/L of AgI in a 0.30 M NaI solution.

A)
B)0.30
C)
D)
E)

Question 41

How many moles of CaF₂ will dissolve in 3.0 liters of 0.089 M NaF solution? (K_sp for CaF₂ = 4.0 $\times$ 10^-11)

A)
B)
C)
D)
E)none of these

Question 42

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

Question 43

What is the limiting reagent in the formation of the lead chloride?

A)Pb²⁺
B)Cl^-
C)(NO₃)^-
D)PbCl₂
E)Pb(NO₃)₂

Question 44

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.

Question 45

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

Question 46

You have a solution consisting of 0.10 M Cl^- and 0.10 M CrO₄^2-.You add 0.10 M silver nitrate dropwise to this solution.Given that the K_sp for Ag₂CrO₄ is 9.0 $\times$ 10^-12,and that for AgCl is 1.6 $\times$ 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

Question 47

You have two salts,AgX and AgY,with very similar K_sp values.You know that K_a for HX is much greater than K_a 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).

Question 48

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 K_a.
E)Both acids are strong.

Question 49

How many moles of Ca(NO₃)₂ must be added to 1.0 L of a 0.182 M KF solution to begin precipitation of CaF₂? For CaF₂,K_sp = 4.0 $\times$ 10^-11.

A)
B)
C)
D)
E)

Question 50

Will precipitation occur?

A)Yes.
B)No.
C)Maybe,it depends on the temperature.
D)Maybe,it depends on the limiting reagent concentration.
E)None of these.

Question 51

Calculate the solubility of Cu(OH)₂ in a solution buffered at pH = 7.59.(K_sp = 1.6 $\times$ 10^-19)

A) M
B) M
C) M
D) M
E)none of these

Question 52

The K_sp of Al(OH)₃ is 2 $\times$ 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

Question 53

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

Question 54

Given the following K_sp values,which statement about solubility in mol/L in water is correct?

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.

Question 55

The K_sp for BaF₂ is 2.4 $\times$ 10^-5.When 10 mL of 0.01 M NaF is mixed with 10 mL of 0.01 M BaNO₃,will a precipitate form?

A)No,because Q is 1 $\times$ 10^-12 and since it is less than K_sp no precipitate will form.
B)Yes,because Q is 1 $\times$ 10^-12 and since it is less than K_sp a precipitate will form.
C)No,because Q is 1.25 $\times$ 10^-7 and since it is less than K_sp no precipitate will form.
D)Yes,because Q is 1.25 $\times$ 10^-7 and since it is less than K_sp a precipitate will form.
E)None of the above.

Question 56

A 50.0-mL sample of 0.100 M Ca(NO₃)₂ is mixed with 50.00 mL of 0.200 M NaF.When the system has come to equilibrium,which of the following sets of conditions will hold? The K_sp for CaF₂ is 4.0 $\times$ 10^-11. Moles Solid CaF₂

A)
B)
C)
D)
E)

Question 57

Determine the equilibrium concentration of the chloride ion.

A)3.9 $\times$ 10^-4
B)8.0 $\times$ 10^-6
C)2.8 $\times$ 10^-3
D)6.1 $\times$ 10^-2
E)none of these

Question 58

The following questions refer to the following system: 3.5 $\times$ 10² mL of 3.2 M Pb(NO₃)₂ and 2.0 $\times$ 10² mL of 0.020 M NaCl are added together.K_sp for the lead chloride is 1.6 $\times$ 10^-5.

-Determine the ion product.

A)1.1 $\times$ 10^-4
B)1.5 $\times$ 10^-2
C)7.8 $\times$ 10^-3
D)8.1 $\times$ 10^-4
E)none of these

Question 59

The solubility in mol/L of M(OH)₂ in 0.053 M KOH is 1.0 $\times$ 10^-5 mol/L.What is the K_sp for M(OH)₂?

A)
B)
C)
D)
E)

Question 60

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.

Question 61

A solution is 0.010 M in each of Pb(NO₃)₂,Mn(NO₃)₂,and Zn(NO₃)₂.Solid NaOH is added until the pH of the solution is 8.50.Which of the following statements is true?

A)No precipitate will form.
B)Only Pb(OH)₂ will precipitate.
C)Only Mn(OH)₂ will precipitate.
D)Only Zn(OH)₂ and Pb(OH)₂ will precipitate.
E)All three hydroxides will precipitate.

Question 62

Which of the following solid salts should be more soluble in 1.0 M NH₃ than in water?

A)Na₂CO₃
B)KCl
C)AgBr
D)KNO₃
E)none of these

Question 63

The overall K_f for the complex ion Ag(NH₃)₂⁺ is 1.7 $\times$ 10⁷.The K_sp for AgI is 1.5 $\times$ 10^-16.What is the molar solubility of AgI in a solution that is 2.0 M in NH₃?

A)1.5 $\times$ 10^-9
B)1.3 $\times$ 10^-3
C)1.0 $\times$ 10^-4
D)5.8 $\times$ 10^-12
E)8.4 $\times$ 10^-5

Question 64

In the qualitative analysis scheme for metal ions,how are the Analytical Group II cations separated from the cations of Analytical Groups III-V?

A)by addition of HCl,forming insoluble metal chlorides
B)by addition of H₂SO₄,forming insoluble metal sulfates
C)by addition of H₂S in acidic solution,forming insoluble metal sulfides
D)by addition of H₂S in basic solution,forming insoluble metal sulfides or hydroxides
E)by addition of (NH₄)₂CO₃ or (NH₄)₃PO₄,forming insoluble metal carbonates or phosphates

Question 65

In the qualitative analysis scheme for metal ions,how are the Analytical Group III cations separated from the cations of Analytical Groups IV and V?

A)by addition of HCl,forming insoluble metal chlorides
B)by addition of H₂SO₄,forming insoluble metal sulfates
C)by addition of H₂S in acidic solution,forming insoluble metal sulfides
D)by addition of H₂S in basic solution,forming insoluble metal sulfides or hydroxides
E)by addition of (NH₄)₂CO₃ or (NH₄)₃PO₄,forming insoluble metal carbonates or phosphates

Question 66

The K_sp for Mn(OH)₂ is 2.0 $\times$ 10^-13.At what pH will Mn(OH)₂ begin to precipitate from a solution in which the initial concentration of Mn²⁺ is 0.10 M?

A)6.47
B)13.3
C)5.85
D)7.03
E)8.15

Question 67

The concentration of Mg²⁺ in seawater is 0.052 M.At what pH will 99% of the Mg²⁺ be precipitated as the hydroxide? [K_sp for Mg(OH)₂ = 8.9 $\times$ 10^-12]

A)8.35
B)9.22
C)6.50
D)10.12
E)4.86

Question 68

An industrial plant processes its waste water through a sedimentation tank that removes hazardous metals by precipitating them as insoluble carbonate salts.If sodium carbonate is gradually added to the tank,what would be the order of precipitation of the metals,Pb²⁺,Cu²⁺,Hg₂²⁺,and Zn²⁺ if each is $\approx$ 1.0 $\times$ 10^-4 M? ( K_sp PbCO₃ = 7.4 $\times$ 10^-14,K_sp CuCO₃ = 1.4 $\times$ 10^-10,K_sp Hg₂CO₃ = 8.9 $\times$ 10^-17,and K_sp ZnCO₃ = 1.4 $\times$ 10^-11)

A)Pb²⁺,Hg₂²⁺,Zn²⁺,Cu²⁺
B)Hg₂²⁺,Pb²⁺,Zn²⁺,Cu²⁺
C)Cu²⁺,Zn²⁺,Pb²⁺,Hg₂²⁺
D)Cu²⁺,Zn²⁺,Hg₂²⁺,Pb²⁺
E)All metal ions will precipitate at the same time.

Question 69

The K_f for the complex ion Ag(NH₃)₂⁺ is 1.7 $\times$ 10⁷.The K_sp for AgCl is 1.6 $\times$ 10^-10.Calculate the molar solubility of AgCl in 1.0 M NH₃.

A)5.2 $\times$ 10^-2
B)4.7 $\times$ 10^-2
C)2.9 $\times$ 10^-3
D)1.3 $\times$ 10^-5
E)1.7 $\times$ 10^-10

Question 70

When a mixture containing cations of Analytical Groups I-III is treated with H₂S in acidic solution,which cations are expected to precipitate?

A)Analytical Group I only
B)Analytical Group II only
C)Analytical Group III only
D)Analytical Groups I and II
E)Analytical Groups II and III

Question 71

A 0.012-mol sample of Na₂SO₄ is added to 400 mL of each of two solutions.One solution contains 1.5 $\times$ 10^-3 M BaCl₂;the other contains 1.5 $\times$ 10^-3 M CaCl₂.Given that K_sp for BaSO₄ = 1.5 $\times$ 10^-9 and K_sp for CaSO₄ = 6.1 $\times$ 10^-5:

A)BaSO₄ would precipitate but CaSO₄ would not.
B)CaSO₄ would precipitate but BaSO₄ would not.
C)Both BaSO₄ and CaSO₄ would precipitate.
D)Neither BaSO₄ nor CaSO₄ would precipitate.
E)Not enough information is given to determine if precipitation would occur.

Question 72

Consider a solution containing the following cations: Na⁺,Hg²⁺,Mn²⁺,Al³⁺ and Ag⁺.Treatment of the solution with dilute HCl followed by saturation with H₂S results in formation of precipitate(s).Which ions still remain in solution (i.e. ,did not precipitate)?

A)Ag⁺ only
B)Na⁺,Hg²⁺,Al³⁺
C)Ag⁺ and Hg²⁺
D)Na⁺,Al³⁺,and Mn²⁺
E)Na⁺ only

Question 73

In the classic scheme for qualitative analysis,the cations of Analytical Group IV are precipitated as phosphates or carbonates.Analytical Group IV consists of

A)alkali metals
B)alkaline earth elements
C)the halogens
D)transition metals having +2 ions
E)none of these

Question 74

Sodium chloride is added slowly to a solution that is 0.010 M in Cu⁺,Ag⁺,and Au⁺.The K_sp values for the chloride salts are 1.9 $\times$ 10^-7,1.6 $\times$ 10^-10,and 2.0 $\times$ 10^-13,respectively.Which compound will precipitate first?

A)CuCl
B)AgCl
C)AuCl
D)All will precipitate at the same time.
E)Cannot be determined.

Question 75

What is the maximum concentration of iodide ions that will precipitate AgI but not PbI₂ from a solution that is M each in Ag⁺ and Pb²⁺? For AgI,K_sp = 1.5 $\times$ 10^-16 and for PbI₂,K_sp = 1.4 $\times$ 10^-8.

A) M
B) M
C) M
D) M
E)None of these;PbI₂ will always precipitate before AgI.

Question 76

What is the maximum concentration of carbonate ions that will precipitate BaCO₃ but not MgCO₃ from a solution that is M each in Mg²⁺ and Ba²⁺? For MgCO₃,K_sp = 1.0 $\times$ 10^-15 and for BaCO₃,K_sp = 2.6 $\times$ 10^-9.

A) M
B) M
C) M
D) M
E)None of these;MgCO₃ will always precipitate before BaCO₃.

Question 77

If 30 mL of 5.0 $\times$ 10^-4 M Ca(NO₃)₂ are added to 70 mL of 2.0 $\times$ 10^-4 M NaF,will a precipitate occur? (K_sp of CaF₂ = 4.0 $\times$ 10^-11)

A)No,because the ion product is greater than K_sp.
B)Yes,because the ion product is less than K_sp.
C)No,because the ion product is less than K_sp.
D)Not enough information is given.
E)Yes,because the ion product is greater than K_sp.

Question 78

A 100.-mL sample of solution contains 10.0 mmol of Ca²⁺ ion.How many mmol of solid Na₂SO₄ must be added in order to cause precipitation of 99.9% of the calcium as CaSO₄? The K_sp of CaSO₄ is 6.1 $\times$ 10^-5.Assume the volume remains constant.

A)17.4
B)10.0
C)61.0
D)71.0
E)6.1

Question 79

In the qualitative analysis scheme for metal ions,how are the Analytical Group I cations separated from the other cations?

A)by addition of HCl,forming insoluble metal chlorides
B)by addition of H₂SO₄,forming insoluble metal sulfates
C)by addition of H₂S in acidic solution,forming insoluble metal sulfides
D)by addition of H₂S in basic solution,forming insoluble metal sulfides or hydroxides
E)by addition of (NH₄)₂CO₃ or (NH₄)₃PO₄,forming insoluble metal carbonates or phosphates

Question 80

A solution contains 0.018 moles each of I^-,Br^-,and Cl^-.When the solution is mixed with 200 mL of 0.24 M AgNO₃,how much AgCl(s)precipitates out?

A)0.0 g
B)1.7 g
C)2.6 g
D)3.3 g
E)5.0 g