Deck 18: Aqueous Ionic Equilibrium

Question 1

Calculate the pH of a solution formed by mixing 150.0 mL of 0.10 M HC₇H₅O₂ with 100.0 mL of 0.30 M NaC₇H₅O₂.The K_a for HC₇H₅O₂ is 6.5 × 10^-5.

A) 4.19
B) 9.69
C) 4.49
D) 4.31
E) 10.51

Answer 1

4.49

Question 2

Calculate the pH of a buffer that is 0.200 M H₃BO₃ and 0.122 M KH₂BO₃.The K_a for H₃BO₃ is 5.8 × 10^-10.

A) 8.93
B) 9.02
C) 10.77
D) 9.46
E) 3.52

Answer 2

9.02

Question 3

Calculate the pH of a solution formed by mixing 100.0 mL of 0.20 M HClO with 200.0 mL of 0.30 M KClO.The K_a for HClO is 2.9 × 10^-8.

A) 5.99
B) 8.01
C) 7.54
D) 7.06
E) 6.46

Answer 3

8.01

Question 4

A 1.00 L buffer solution is 0.150 M in HC₇H₅O₂ and 0.250 M in LiC₇H₅O₂.Calculate the pH of the solution after the addition of 100.0 mL of 1.00 M HCl.The K_a for HC₇H₅O₂ is 6.5 × 10^-5.

A) 4.19
B) 5.03
C) 4.41
D) 3.34
E) 3.97

Question 5

Calculate the pH of a buffer that is 0.225 M HC₂H₃O₂ and 0.162 M KC₂H₃O₂.The K_a for HC₂H₃O₂ is 1.8 × 10^-5.

A) 4.89
B) 9.11
C) 4.74
D) 9.26
E) 4.60

Question 6

Calculate the pH of a solution formed by mixing 250.0 mL of 0.15 M NH₄Cl with 100.0 mL of 0.20 M NH₃.The K_b for NH₃ is 1.8 × 10^-5.

A) 9.13
B) 9.25
C) 9.53
D) 4.74
E) 8.98

Question 7

If the pKa of HCHO₂ is 3.74 and the pH of an HCHO₂/NaCHO₂ solution is 3.11,which of the following is TRUE?

A) [HCHO₂] < [NaCHO₂]
B) [HCHO₂] = [NaCHO₂]
C) [HCHO₂] << [NaCHO₂]
D) [HCHO₂] > [NaCHO₂]
E) It is not possible to make a buffer of this pH from HCHO₂ and NaCHO₂.

Question 8

A 1.00 L buffer solution is 0.250 M in HF and 0.250 M in NaF.Calculate the pH of the solution after the addition of 100.0 mL of 1.00 M HCl.The K_a for HF is 3.5 × 10^-4.

A) 3.09
B) 4.11
C) 3.82
D) 3.46
E) 2.78

Question 9

Calculate the pH of a solution formed by mixing 250.0 mL of 0.15 M NH₄Cl with 200.0 mL of 0.12 M NH₃.The K_b for NH₃ is 1.8 × 10^-5.

A) 9.06
B) 9.45
C) 4.55
D) 4.74
E) 9.26

Question 10

Identify a good buffer.

A) small amounts of both a weak acid and its conjugate base
B) significant amounts of both a strong acid and a strong base
C) small amounts of both a strong acid and a strong base
D) significant amounts of both a weak acid and a strong acid
E) significant amounts of both a weak acid and its conjugate base

Question 11

Calculate the pH of a solution formed by mixing 200.0 mL of 0.30 M HClO with 300.0 mL of 0.20 M KClO.The K_a for HClO is 2.9 × 10^-8.

A) 5.99
B) 8.01
C) 7.54
D) 7.06
E) 6.46

Question 12

Calculate the pH of a solution formed by mixing 200.0 mL of 0.30 M HClO with 100.0 mL of 0.20 M KClO.The K_a for HClO is 2.9 × 10^-8.

A) 5.99
B) 8.01
C) 7.54
D) 7.06
E) 6.46

Question 13

An important buffer in the blood is a mixture of

A) sodium chloride and hydrochloric acid.
B) hydrochloric acid and sodium hydroxide.
C) carbonic acid and bicarbonate ion.
D) acetic acid and bicarbonate ion.
E) acetic acid and carbonate ion.

Question 14

Calculate the pH of a solution formed by mixing 250.0 mL of 0.15 M HCHO₂ with 100.0 mL of 0.20 M LiCHO₂.The K_a for HCHO₂ is 1.8 × 10^-4.

A) 3.87
B) 3.74
C) 10.53
D) 3.47
E) 10.13

Question 15

If the pKa of HCHO₂ is 3.74 and the pH of an HCHO₂/NaCHO₂ solution is 3.89,which of the following is TRUE?

A) [HCHO₂] < [NaCHO₂]
B) [HCHO₂] = [NaCHO₂]
C) [HCHO₂] > [NaCHO₂]
D) [HCHO₂] >> [NaCHO₂]
E) It is not possible to make a buffer of this pH from HCHO₂ and NaCHO₂.

Question 16

If the pKa of HCHO₂ is 3.74 and the pH of an HCHO₂/NaCHO₂ solution is 3.74,which of the following is TRUE?

A) [HCHO₂] > [NaCHO₂]
B) [HCHO₂] = [NaCHO₂]
C) [HCHO₂] < [NaCHO₂]
D) [HCHO₂] < <[NaCHO₂]
E) It is not possible to make a buffer of this pH from HCHO₂ and NaCHO₂.

Question 17

If a chemist wishes to prepare a buffer that will be effective at a pH of 3.00 at 25°C,the best choice would be an acid component with a K_a equal to

A) 9.10 × 10^-2.
B) 9.10 × 10^-4.
C) 9.10 × 10^-6.
D) 9.10 × 10^-8.
E) 9.10 × 10^-10.

Question 18

A 1.00 L buffer solution is 0.250 M in HF and 0.250 M in LiF.Calculate the pH of the solution after the addition of 0.150 moles of solid LiOH.Assume no volume change upon the addition of base.The K_a for HF is 3.5 × 10^-4.

A) 3.46
B) 4.06
C) 2.85
D) 3.63
E) 4.24

Question 19

Animals will lick up ethylene glycol (antifreeze)due to its sweet taste.The antidote for ethylene glycol poisoning is the administration of

A) ethyl alcohol ( alcoholic drinks).
B) isopropyl alcohol (rubbing alcohol).
C) mineral oil (laxative).
D) vinegar.
E) sodium bicarbonate (baking soda).

Question 20

Calculate the pH of a solution formed by mixing 250.0 mL of 0.900 M NH₄Cl with 250.0 mL of 1.60 M NH₃.The K_b for NH₃ is 1.8 × 10^-5.

A) 8.25
B) 9.18
C) 9.50
D) 10.12
E) 10.83

Question 21

A 1.50 L buffer solution is 0.250 M in HF and 0.250 M in NaF.Calculate the pH of the solution after the addition of 0.100 moles of solid NaOH.Assume no volume change upon the addition of base.The K_a for HF is 3.5 × 10^-4.

A) 3.22
B) 3.82
C) 3.69
D) 3.09
E) 4.46

Question 22

A 100.0 mL sample of 0.10 M NH₃ is titrated with 0.10 M HNO₃.Determine the pH of the solution after the addition of 50.0 mL of HNO₃.The K_b of NH₃ is 1.8 × 10^-5.

A) 4.74
B) 7.78
C) 7.05
D) 9.26
E) 10.34

Question 23

A 100.0 mL sample of 0.18 M HClO₄ is titrated with 0.27 M LiOH.Determine the pH of the solution after the addition of 50.0 mL of LiOH.

A) 12.48
B) 0.68
C) 2.35
D) 1.52
E) 3.22

Question 24

A 100.0 mL sample of 0.18 M HClO₄ is titrated with 0.27 M LiOH.Determine the pH of the solution before the addition of any LiOH.

A) 1.74
B) 1.05
C) 0.74
D) 0.57
E) 1.57

Question 25

Which of the following is TRUE?

A) An effective buffer has a [base]/[acid] ratio in the range of 10 - 100.
B) A buffer is most resistant to pH change when [acid] = [conjugate base]
C) An effective buffer has very small absolute concentrations of acid and conjugate base.
D) A buffer can not be destroyed by adding too much strong base. It can only be destroyed by adding too much strong acid.
E) None of the above are true.

Question 26

A 1.50 L buffer solution is 0.250 M in HF and 0.250 M in NaF.Calculate the pH of the solution after the addition of 0.0500 moles of solid NaOH.Assume no volume change upon the addition of base.The K_a for HF is 3.5 × 10^-4.

A) 3.34
B) 3.46
C) 3.57
D) 3.63
E) 2.89

Question 27

When titrating a monoprotic strong acid with a weak base at 25°C,the

A) pH will be 7 at the equivalence point.
B) pH will be greater than 7 at the equivalence point.
C) titration will require more moles of the base than acid to reach the equivalence point.
D) titration will require more moles of acid than base to reach the equivalence point.
E) pH will be less than 7 at the equivalence point.

Question 28

A 100.0 mL sample of 0.20 M HF is titrated with 0.10 M KOH.Determine the pH of the solution before the addition of any KOH.The K_a of HF is 3.5 × 10^-4.

A) 4.15
B) 0.70
C) 2.08
D) 3.46
E) 1.00

Question 29

When titrating a strong monoprotic acid with KOH at 25°C,the

A) pH will be less than 7 at the equivalence point.
B) pH will be greater than 7 at the equivalence point.
C) titration will require more moles of base than acid to reach the equivalence point.
D) pH will be equal to 7 at the equivalence point.
E) titration will require more moles of acid than base to reach the equivalence point.

Question 30

When titrating a weak monoprotic acid with NaOH at 25°C,the

A) pH will be less than 7 at the equivalence point.
B) pH will be equal to 7 at the equivalence point.
C) pH will be greater than 7 at the equivalence point.
D) titration will require more moles of base than acid to reach the equivalence point.
E) titration will require more moles of acid than base to reach the equivalence point.

Question 31

A 100.0 mL sample of 0.180 M HClO₄ is titrated with 0.270 M LiOH.Determine the pH of the solution after the addition of 75.0 mL of LiOH.

A) 12.1
B) 2.65
C) 11.35
D) 1.89
E) 13.06

Question 32

A 100.0 mL sample of 0.10 M NH₃ is titrated with 0.10 M HNO₃.Determine the pH of the solution after the addition of 150.0 mL of HNO₃.The K_b of NH₃ is 1.8 × 10^-5.

A) 1.70
B) 6.44
C) 7.56
D) 12.30
E) 2.30

Question 33

A 100.0 mL sample of 0.10 M NH₃ is titrated with 0.10 M HNO₃.Determine the pH of the solution before the addition of any HNO₃.The K_b of NH₃ is 1.8 × 10^-5.

A) 4.74
B) 9.26
C) 11.13
D) 13.00
E) 12.55

Question 34

A 100.0 mL sample of 0.20 M HF is titrated with 0.10 M KOH.Determine the pH of the solution after the addition of 100.0 mL of KOH.The K_a of HF is 3.5 × 10^-4.

A) 2.08
B) 3.15
C) 4.33
D) 3.46
E) 4.15

Question 35

A weak acid is titrated with a strong base to the equivalence point.The pH of the resulting solution is found to be 9.18.The pK_a of the acid is

A) 9.18.
B) 7.00.
C) 4.59.
D) 2.50.
E) 6.28.

Question 36

A 100.0 mL sample of 0.18 M HClO₄ is titrated with 0.27 M LiOH.Determine the pH of the solution after the addition of 100.0 mL of LiOH.

A) 13.13
B) 12.65
C) 1.35
D) 0.87
E) 12.95

Question 37

A 100.0 mL sample of 0.18 M HClO₄ is titrated with 0.27 M LiOH.Determine the pH of the solution after the addition of 30.0 mL of LiOH.

A) 0.86
B) 1.21
C) 2.00
D) 1.12
E) 2.86

Question 38

Define buffer capacity.

A) Buffer capacity is the amount of acid or base that can be added to a buffer without destroying its effectiveness.
B) Buffer capacity is the amount of acid that can be added until all of the base is used up.
C) Buffer capacity is the amount of base that can be added until all of the acid is used up.
D) Buffer capacity is the amount of acid that can be added until all of the acid is used up.
E) Buffer capacity is the amount of base that can be added until all of the base is used up.

Question 39

A 100.0 mL sample of 0.18 M HClO₄ is titrated with 0.27 M LiOH.Determine the pH of the solution after the addition of 66.67 mL of LiOH (this is the equivalence point).

A) 0.97
B) 13.03
C) 2.76
D) 11.24
E) 7.00

Question 40

Which of the following is TRUE?

A) The equivalence point is where the amount of acid equals the amount of base during any acid-base titration.
B) At the equivalence point, the pH is always 7.
C) An indicator is not pH sensitive.
D) A titration curve is a plot of pH vs. the [base]/[acid] ratio.
E) None of the above are true.

Question 41

Determine the molar solubility of BaF₂ in pure water.K_sp for BaF₂ = 2.45 × 10^-5.

A) 1.83 × 10^-2 M
B) 1.23 × 10^-5 M
C) 2.90 × 10^-2 M
D) 4.95 × 10^-3 M
E) 6.13 × 10^-6 M

Question 42

A 100.0 mL sample of 0.20 M HF is titrated with 0.10 M KOH.Determine the pH of the solution after the addition of 300.0 mL of KOH.The K_a of HF is 3.5 × 10^-4.

A) 12.40
B) 9.33
C) 5.06
D) 8.94
E) 12.00

Question 43

Determine the molar solubility of Fe(OH)₂ in pure water.K_sp for Fe(OH)₂= 4.87 × 10^-17.

A) 2.44 × 10^-17 M
B) 1.62 × 10^-17 M
C) 4.03 × 10^-9 M
D) 3.65 × 10^-6 M
E) 2.30 × 10^-6 M

Question 44

A 100.0 mL sample of 0.10 M Ca(OH)₂ is titrated with 0.10 M HBr.Determine the pH of the solution after the addition of 100.0 mL HBr.

A) 2.00
B) 12.00
C) 1.30
D) 12.70
E) 7.00

Question 45

A 100.0 mL sample of 0.20 M HF is titrated with 0.10 M KOH.Determine the pH of the solution after the addition of 400.0 mL of KOH.The K_a of HF is 3.5 × 10^-4.

A) 13.08
B) 12.60
C) 13.85
D) 12.30
E) 12.78

Question 46

Determine the molar solubility of AgBr in a solution containing 0.150 M NaBr.K_sp (AgBr)= 7.7 × 10^-13.

A) 8.8 × 10^-7 M
B) 3.9 × 10^-13 M
C) 5.8 × 10^-5 M
D) 5.1 × 10^-12 M
E) 0.150 M

Question 47

Determine the molar solubility of AgI in pure water.K_sp (AgI)= 8.51 × 10^-17.

A) 9.22 × 10^-9 M
B) 4.26 × 10^-17 M
C) 8.51 × 10^-17 M
D) 2.77 × 10^-6 M
E) 4.40 × 10^-6 M

Question 48

Determine the molar solubility for Al(OH)₃ in pure water.K_sp for Al(OH)₃ = 1.3 × 10^-33.

A) 3.6 × 10^-12 M
B) 2.2 × 10^-10 M
C) 4.8 × 10^-35 M
D) 2.6 × 10^-9 M
E) 6.0 × 10^-19 M

Question 49

Determine the molar solubility of Pb(IO₃)₂ in pure water.K_sp for Pb(IO₃)₂ = 2.60 × 10^-13.

A) 4.02 × 10^-5 M
B) 9.35 × 10^-6 M
C) 5.08 × 10^-7 M
D) 6.48 × 10^-5 M
E) 2.23 × 10^-6 M

Question 50

Determine the molar solubility for Pb₃(PO₄)₂ in pure water.K_sp for Pb₃(PO₄)₂ is 1.0 × 10^-54.

A) 4.1 × 10^-28 M
B) 5.8 × 10^-10 M
C) 1.1 × 10^-11 M
D) 6.2 × 10^-12 M
E) 1.0 × 10^-54 M

Question 51

A 100.0 mL sample of 0.10 M Ca(OH)₂ is titrated with 0.10 M HBr.Determine the pH of the solution after the addition of 300.0 mL HBr.

A) 1.60
B) 1.30
C) 1.00
D) 12.40
E) 1.12

Question 52

A 100.0 mL sample of 0.10 M Ca(OH)₂ is titrated with 0.10 M HBr.Determine the pH of the solution after the addition of 400.0 mL HBr.

A) 1.00
B) 1.40
C) 1.22
D) 1.30
E) 2.11

Question 53

Determine the molar solubility of PbSO₄ in pure water.K_sp (PbSO₄)= 1.82 × 10^-8.

A) 1.82 × 10^-8 M
B) 1.35 × 10^-4 M
C) 9.1 × 10^-9 M
D) 3.31 × 10^-16 M
E) 4.48 × 10^-4 M

Question 54

Determine the molar solubility of AgBr in a solution containing 0.200 M NaBr.K_sp (AgBr)= 7.7 × 10^-13.

A) 8.8 × 10^-7 M
B) 1.54 × 10^-13 M
C) 5.8 × 10^-5 M
D) 3.8 × 10^-12 M
E) 0.200 M

Question 55

A 100.0 mL sample of 0.20 M HF is titrated with 0.10 M KOH.Determine the pH of the solution after the addition of 200.0 mL of KOH.The K_a of HF is 3.5 × 10^-4.

A) 9.62
B) 7.00
C) 3.46
D) 10.54
E) 8.14

Question 56

A 100.0 mL sample of 0.10 M Ca(OH)₂ is titrated with 0.10 M HBr.Determine the pH of the solution after the addition of 200.0 mL HBr.

A) 2.62
B) 2.00
C) 1.48
D) 12.52
E) 7.00

Question 57

A 100.0 mL sample of 0.10 M NH₃ is titrated with 0.10 M HNO₃.Determine the pH of the solution after the addition of 100.0 mL of HNO₃.The K_b of NH₃ is 1.8 × 10^-5.

A) 6.58
B) 10.56
C) 8.72
D) 3.44
E) 5.28

Question 58

Determine the molar solubility of MgCO₃ in pure water.K_sp (MgCO₃)= 6.82 × 10^-6.

A) 6.82 × 10^-6 M
B) 3.41 × 10^-6 M
C) 4.65 × 10^-3 M
D) 2.61 × 10^-3 M
E) 3.25 × 10^-4 M

Question 59

A 100.0 mL sample of 0.10 M NH₃ is titrated with 0.10 M HNO₃.Determine the pH of the solution after the addition of 200.0 mL of HNO₃.The K_b of NH₃ is 1.8 × 10^-5.

A) 6.44
B) 1.48
C) 2.00
D) 12.52
E) 12.00

Question 60

A 100.0 mL sample of 0.10 M Ca(OH)₂ is titrated with 0.10 M HBr.Determine the pH of the solution before the addition of any HBr.

A) 12.86
B) 13.00
C) 13.30
D) 0.70
E) 1.00

Question 61

Give the equation for a saturated solution in comparing Q with K_sp.

A) Q > K_sp
B) Q < K_sp
C) Q = K_sp
D) Q ≠ K_sp
E) none of the above

Question 62

Determine the molar solubility of Al(OH)₃ in a solution containing 0.0500 M AlCl₃.K_sp (Al(OH)₃)= 1.3 × 10^-33.

A) 2.6 × 10-9M
B) 5.2 × 10^-31 M
C) 9.87 × 10^-12 M
D) 1.04 × 10^-29 M
E) 6.5 × 10^-35 M

Question 63

The molar solubility of Ba₃(PO₄)₂ is 8.89 × 10^-9 M in pure water.Calculate the K_sp for Ba₃(PO₄)₂.

A) 4.94 × 10^-49
B) 5.55 × 10^-41
C) 5.33 × 10^-37
D) 8.16 × 10^-31
E) 6.00 × 10^-39

Question 64

Determine the molar solubility for Zn(OH)₂ in pure water.K_sp for Zn(OH)₂ is 3.00 × 10^-17.

A) 3.0 × 10^-17 M
B) 7.5 × 10^-18 M
C) 3.11 × 10^-6 M
D) 1.96 × 10^-6 M
E) 5.5 × 10^-19 M

Question 65

A solution contains 0.036 M Cu²⁺ and 0.044 M Fe²⁺.A solution containing sulfide ions is added to selectively precipitate one of the metal ions from solution.At what concentration of sulfide ion will a precipitate begin to form? What is the identity of the precipitate?
K_sp(CuS)= 1.3 × 10^-36,K_sp(FeS)= 6.3 × 10^-18.

A) 1.4 × 10^-16 M, FeS
B) 3.6 × 10^-35 M, CuS
C) 3.6 × 10^-35 M, FeS
D) 1.4 × 10^-16 M, CuS
E) No precipitate will form at any concentration of sulfide ion.

Question 66

A solution contains 0.021 M Cl⁻ and 0.017 M I⁻.A solution containing copper (I)ions is added to selectively precipitate one of the ions.At what concentration of copper (I)ion will a precipitate begin to form? What is the identity of the precipitate?
K_sp(CuCl)= 1.0 × 10^-6,K_sp(CuI)= 5.1 × 10^-12.

A) 3.0 × 10^-10 M, CuI
B) 3.0 × 10^-10 M, CuCl
C) 4.8 × 10^-5 M, CuCl
D) 4.8 × 10^-5 M, CuI
E) No precipitate will form at any concentration of copper (I).

Question 67

A solution containing CaCl₂ is mixed with a solution of Li₂C₂O₄ to form a solution that is 3.5 × 10^-4 M in calcium ion and 2.33 × 10^-4 M in oxalate ion.What will happen once these solutions are mixed? K_sp (CaC₂O₄)= 2.3 × 10^-9.

A) Nothing will happen since both calcium chloride and lithium oxalate are soluble compounds.
B) Nothing will happen K_sp > Q for all possible precipitants.
C) A precipitate will form as calcium oxalate is not soluble to any extent.
D) A precipitate will form since Q > K_sp for calcium oxalate.
E) There is not enough information to determine.

Question 68

A solution containing AgNO₃ is mixed with a solution of NaCl to form a solution that is 0.10 M in AgNO₃ and 0.075 M in NaCl.What will happen once these solutions are mixed? K_sp (AgCl)= 1.77 × 10^-10.

A) Nothing will happen since the molar solubility of AgCl is higher than the solution concentrations.
B) Silver chloride will precipitate out of solution, leaving an unsaturated solution of AgCl.
C) Silver chloride will precipitate out of solution, leaving a saturated AgCl solution.
D) Nothing will happen since NaCl and AgNO₃ are both soluble compounds.
E) There is not enough information to say anything about this solution.

Question 69

Stalactites and stalagmites form as ________ precipitates out of the water evaporating in underground caves.

A) hydrochloric acid
B) sodium hydroxide
C) sodium chloride
D) calcium carbonate
E) sodium bicarbonate

Question 70

Determine the molar solubility of BaF₂ in a solution containing 0.0750 M LiF.K_sp (BaF₂)= 1.7 × 10^-6.

A) 2.3 × 10^-5 M
B) 8.5 × 10^-7 M
C) 1.2 × 10^-2 M
D) 0.0750 M
E) 3.0 × 10^-4 M

Question 71

The molar solubility of Ag₂S is 1.26 × 10^-16 M in pure water.Calculate the K_sp for Ag₂S.

A) 1.59 × 10^-32
B) 1.12 × 10^-8
C) 6.81 × 10^-63
D) 3.78 × 10^-12
E) 8.00 × 10^-48

Question 72

Determine the molar solubility for Cd(OH)₂ in pure water.K_sp for Cd(OH)₂ is 2.0 × 10^-14.

A) 2.0 × 10^-14 M
B) 1.7 × 10^-5 M
C) 6.6 × 10^-8 M
D) 3.5 × 10^-6 M
E) 2.9 × 10^-6 M

Question 73

Determine the solubility for CuC₂O₄(s)in pure water.K_sp for is 2.9 × 10^-8.

A) 0.0036 g L^-1
B) 0.069 g L^-1
C) 0.026 g L^-1
D) 0.18 g L^-1
E) 0.0083 g L^-1

Question 74

A solution contains 2.2 × 10^-3 M in Cu²⁺ and 0.33 M in LiCN.If the K_f for Cu(CN)₄^2- is 1.0 × 10²⁵,how much copper ion remains at equilibrium?

A) 3.8 × 10^-24 M
B) 1.9 × 10^-26 M
C) 6.7 × 10^-28 M
D) 2.9 × 10^-27 M
E) 4.6 × 10^-25 M

Question 75

Give the equation for a supersaturated solution in comparing Q with K_sp.

A) Q > K_sp
B) Q < K_sp
C) Q = K_sp
D) Q ≠ K_sp
E) none of the above

Question 76

The molar solubility of CaF₂ is 2.15 × 10^-4 M in pure water.Calculate the K_sp for CaF₂.

A) 1.63 × 10^-12
B) 8.05 × 10^-9
C) 3.97 × 10^-11
D) 4.47 × 10^-12
E) 5.31 × 10^-10

Question 77

The molar solubility of ZnS is 1.6 × 10^-12 M in pure water.Calculate the K_sp for ZnS.

A) 8.0 × 10^-13
B) 3.2 × 10^-12
C) 1.6 × 10^-35
D) 2.6 × 10^-24
E) 6.80 × 10^-5

Question 78

Give the equation for an unsaturated solution in comparing Q with K_sp.

A) Q > K_sp
B) Q < K_sp
C) Q = K_sp
D) Q ≠ K_sp
E) none of the above

Question 79

A solution containing CaCl₂ is mixed with a solution of Li₂C₂O₄ to form a solution that is 2.1 × 10^-5 M in calcium ion and 4.75 × 10^-5 M in oxalate ion.What will happen once these solutions are mixed? K_sp (CaC₂O₄)= 2.3 × 10^-9.

A) A precipitate will form since Q > K_sp for calcium oxalate.
B) Nothing will happen since both calcium chloride and lithium oxalate are soluble compounds.
C) Nothing will happen since calcium oxalate is extremely soluble.
D) Nothing will happen since K_sp > Q for all possible precipitants.
E) There is not enough information to determine.

Question 80

The molar solubility of CuI is 2.26 × 10^-6 M in pure water.Calculate the K_sp for CuI.

A) 5.11 × 10^-12
B) 4.52 × 10^-6
C) 1.50 × 10^-3
D) 4.62 × 10^-17
E) 1.02 × 10^-11