Ch.16 - Aqueous Equilibrium WorksheetSee all chapters
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Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds
Additional Problems
A solution contains 0.015 M Ba2+ and 0.015 Ag+ . Na2SO4 (s) is slowly added to the solution. Does silver sulfate or barium sulfate precipitate first? How much of the first precipitated ion remains when the second ion begins to precipitate? a. BaSO4, 1.1 x 10 -3 Ba + remains b. BaSO4, 1.5 x 10 -9 Ba+ remains c. BaSO4, 7.6 x 10 -2 Ba+ remains d. Ag2SO4, 7.6 x 10 -2 Ag2+ remains e. Ag2SO4, 1.5 x 10 -9 Ag2+ remains 
Consider a solution containing the group III cations Ni 2+ and Mn 2+ (each with a concentration of 0.10 M) is treated with thioacetamide and heated to 80°C while buffered at a pH of 8. Which of the following statements best describes the solution after the reaction? a. The cations remain dissolved in solution b. NiS and MnS precipitates form c. NiS and MnS precipitates partially form d. Ni(OH)2 and Mn(OH)2 precipitates form e. Ni(OH)2 and Mn(OH)2 precipitates partially form
Consider the following Ksp values for metal sulfides: Which pair would be most difficult to separate by fractional precipitation?
Ksp = 6.3 x 10-5 for the following hypothetical equation. Each of the following mixture is prepared with the indicated molarity of A2+ and B3- at 95°C and then allowed to cool to room temperature. Which of the mixtures would produce a precipitate of A3B2? A3B2 (s)  ⇌  3 A2+ (aq) + 2 B 3- (aq) a. [A2+] = 0.036 M and [B 3-] = 0.300 M b. [A2+] = 0.272 M and [B 3-] = 0.042 M c. [A2+] = 0.150 M and [B 3-] = 0.028 M d. [A2+] = 0.086 M and [B 3-] = 0.895 M e. [A2+] = 0.682 M and [B 3-] = 0.003  
For BaCrO4 (Ksp = 1.17 × 10–10), will a precipitate of BaCrO4 form when 0.10 L of  6.0 × 10–2 M Ba(NO3)2 is added to 400 mL of 5.0 × 10–8 M Na2CrO4? A)      Yes, because Q > Ksp.              D)        No, because Q = Ksp. B)      No, because Q < Ksp.                E)        Yes, because Q < Ksp. C)      Yes, because Q = Ksp
When equal volumes of each solution are mixed, which combination will produce a precipitate of PbI2? (Ksp of PbI2 = 8.5 × 10−9) (a) 2.0 × 10−3 M Pb(NO3)2 and 2.0 × 10−4 M NaI (b) 4.0 × 10−2 M Pb(NO3)2 and 8.0 × 10−5 M NaI (c) 2.0 × 10−3 M Pb(NO3)2 and 4.0 × 10−2 M NaI (d) 4.0 × 10−3 M Pb(NO3)2 and 2.0 × 10−3 M NaI (e) None of the above.
Ksp for CaF2 is 3.9 × 10−11. Would a precipitate of CaF2 form if Ca(NO3)2 and NaF solutions were mixed such that [Ca2+] = 2.0 × 10−4 M, and [F−] = 3.0 × 10−4 M? 1. no  2. yes, because Q is smaller than Ksp 3. yes, because Q is larger than Ksp
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? Ksp (AgCl) = 1.77 × 10 -10. A) Nothing will happen since the molar solubility of AgCl is higher than the solution concentrations. B). Nothing will happen since NaCl and AgNO3 are both soluble compounds. C) Silver chloride will precipitate out of solution, leaving an unsaturated solution of AgCl D) Silver chloride will precipitate out of solution, leaving a saturated AgCl solution. E) There is not enough information to say anything about this solution.
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? Ksp(CuCl) = 1.0 × 10 -6 Ksp(CuI) = 5.1 × 10 -12 A) 4.8 × 10-5 M, CuI B) 3.0 × 10-10 M, CuCl C) 4.8 × 10-5 M, CuCl D) 3.0 × 10-10 M, CuI E) No precipitate will form at any concentration of copper (I).
Will a precipitate form when 10 mL of 0.015 M [Hg +] and 10 mL of 0.015 M [SO 42−] are mixed? Ksp of Hg2SO4 is 6.5x10−7. a. Yes; Q = 3.4 × 10 −6 which is larger than Ksp, a precipitate will form. b. No; Q = 3.4 × 10 −6 which is larger than Ksp, a precipitate will not form. c. Yes; Q = 4.2 × 10 −7 which is smaller than Ksp, a precipitate will form. d. No; Q = 4.2 × 10 −7 which is smaller than Ksp, a precipitate will not form. e. No; Q = 3.4 × 10 −12 which is smaller than Ksp, a precipitate will not form.
Give the equation for an unsaturated solution in comparing Q with K sp. A) Q > Ksp B) Q < Ksp C) Q = Ksp D) Q ≠ Ksp E) none of the above
Will a precipitate form when 10 mL of 0.015 M [Hg +] and 10 mL of 0.015 M [SO 4 2-] are mixed?  Ksp of Hg2SO4 is 6.5 x 10 -7. a. Yes; Q = 3.4 x 10 -6 which is larger than Ksp, a precipitate will form.  b. No; Q = 3.4 x 10 -6 which is larger than Ksp, a precipitate will not form. c. Yes, Q = 4.2 x 10 -7 which is smaller than Ksp, a precipitate will form.  d. No; Q = 4.2 x 10 -7 which is smaller than Ksp, a precipitate will not form.  e. No; Q = 3.4 x 10 -12 which is smaller than Ksp, a precipitate will not form. 
Solutions of 0.00024 M aqueous sodium iodide and 0.0054 M aqueous lead (II) nitrate, Pb(NO3)2 are mixed together. Which of the following is the most likely result that a student would observe? Assume no volume change. Ksp of Pbl2 is 1.4 x 10-8. A. All ions remain in solution and no precipitate is observed. B. A precipitate of sodium nitrate, NaNO3, is observed. C. A precipitate of lead (II) iodide, Pbl 2, is observed. D. The mixture results in the formation of a saturated solution at equilibrium. E. The Nal and Pb(NO3)2 solutions do not mix and two separate layers are formed.
What will be the result if 100 mL of 0.06 M Mg(NO 3)2 is added to 50 mL of 0.06 M Na2C2O4? Assume the reaction is taking place at 25°C. Substance              Ksp, 25°C MgC2O4(s)           8.6 x 10 –5 A) No precipitate will form. B) A precipitate will form and an excess of Mg 2+ ions will remain in solution. C) A precipitate will form and an excess of C2O42– ions will remain in solution. D) A precipitate will form, but neither ion is present in excess. 
A solution contains 0.20 M CrO 4 2- , 0.10 M CO 3 2- , and 0.010 M Cl - . If solid AgNO3 is added slowly to the solution without changing the total volume of the solution, in what order will the precipitates, Ag2CrO4, Ag2CO3, and AgCl, form? a. 1st: Ag2CO3        2nd: Ag 2CrO4         3rd: AgCl b. 1st: Ag2CrO4       2nd: Ag 2CO3          3rd: AgCl c. 1st: AgCl              2nd: Ag 2CrO4         3rd: Ag 2CO3 d. 1st: AgCl              2nd: Ag  2CO3          3rd: Ag 2CrO4 e. 1st: Ag2CO3        2nd: AgCl               3rd: Ag  2CrO4
Selective precipitation. In this example Cu2+ ions are separated from Zn2+ ions.What would happen if the pH were raised to 8 first and then H2S were added?
Predict whether or not a precipitate will form upon mixing 75.0 mL of a NaOH solution with pOH = 2.58 with 125.0 mL of a 0.018 M MgCl2 solution. Identify the precipitate, if any.
Potassium hydroxide is used to precipitate each of the cations from their respective solution. Determine the minimum concentration of KOH required for precipitation to begin in each case.1.6×10−2 M CaCl2
Potassium hydroxide is used to precipitate each of the cations from their respective solution. Determine the minimum concentration of KOH required for precipitation to begin in each case.1.8×10−3 M MgBr2
If a precipitate forms when HCl is added to an aqueous solution, what conclusions can you draw about the contents of the solution?
Consider a solution that is 2.3×10−2 M in Fe2 + and 1.6×10−2 M in Mg2 + .What is the remaining concentration of the cation that precipitates first, when the other cation just begins to precipitate?
Consider a solution that is 2.3×10−2 M in Fe2 + and 1.6×10−2 M in Mg2 + .If potassium carbonate is used to selectively precipitate one of the cations while leaving the other cation in solution, which cation will precipitate first?
Calculate the concentration of I- in a solution obtained by shaking 0.16 M KI with an excess of AgCl(s).
What volume of 0.116 M sodium carbonate solution is required to precipitate 99% of the Mg from 1.00 L of 0.100 M magnesium nitrate solution?
For a given solution containing an ionic compound, what is the relationship between Q, Ksp, and the relative saturation of the solution?
What is selective precipitation? What are the conditions under which selective precipitation may occur?
Will Ca(OH)2 precipitate from solution if the pH of a 6.0×10−2 M solution of CaCl2 is adjusted to 8.0?
Fluoridation of drinking water is employed in many places to aid in the prevention of dental caries. Typically the F- ion concentration is adjusted to about 1 ppb. Some water supplies are also "hard"; that is, they contain certain cations such as Ca2+ that interfere with the action of soap. Consider a case where the concentration of Ca2+ is 8 ppb.Could a precipitate of CaF2 form under these conditions? (Make any necessary approximations.)
Calculate the minimum pH needed to precipitate Mn(OH)2 so completely that the concentration of Mn2+ is less than 1g per liter [1 part per billion (ppb)].
Give the equation for a saturated solution in comparing Q with K sp.A) Q > KspB) Q < KspC) Q = KspD) Q ≠ KspE) none of the above
What is the value of Q when the solution contains 2.50x103 M Mg2+ and 2.00x103 M CO32?
Consider the relative saturation of a solution. If Q sp = Ksp, the solution is ______________; if Q sp > Ksp, the solution is ______________ , and if Q sp < Ksp, the solution is ______________.
A solution is 5.0 x 10-5 M in each of these ions: Ag+ , SO42-, Cl-, CO32- Which precipitate will form?a. Ag2SO4 (Ksp = 1.12 x 10-5)b. AgCl (Ksp = 1.77 x 10-10)c. Ag2CO3 (Ksp = 8.46 x 10-12)
Consider the solubility of lead (II) chloride, The equilibrium constant, Ksp, is 1.2 × 10−5. If 100 mL each of 0.02 M KCl and 0.02 M Pb(NO3)2, both strong electrolytes, are mixed together, what will take place? 1. A precipitate of PbCl2 would form. 2. No precipitate would form. 3. There is not enough information. 4. A precipitate of KNO3 would form.
Which of the following compounds precipitates from a solution that has the concentrations indicated? (See Appendix J for Ksp values.)(a) CaCO3: [Ca2+] = 0.003 M, [CO32−] = 0.003 M(b) Co(OH)2: [Co2+] = 0.01 M, [OH–] = 1 x 10–7 M(c) CaHPO4: [Ca2+] = 0.01 M, [HPO42−] = 2 x 10–6 M(d) Pb3(PO4)2: [Pb2+] = 0.01 M, [PO43−] = 1 x 10–13 M
A 1.0 M Na2SO4 solution is slowly added to 10.0 mL of a solution that is 0.20 M in Ca2+ and 0.30 M in Ag+.How much Na2SO4 solution must be added to initiate the precipitation?
Calculate the concentration of Tl+ when TlCl just begins to precipitate from a solution that is 0.0250 M in Cl–.
Calculate the concentration of sulfate ion when BaSO4 just begins to precipitate from a solution that is 0.0758 M in Ba2+.
Calculate the concentration of Sr2+ when SrF2 starts to precipitate from a solution that is 0.0025 M in F–.
Calculate the concentration of PO43− when Ag3PO4 starts to precipitate from a solution that is 0.0125 M in Ag+.
Calculate the concentration of F– required to begin precipitation of CaF2 in a solution that is 0.010 M in Ca2+.
A solution containing sodium fluoride is mixed with one containing calcium nitrate to form a solution that is 0.015 M in NaF and 0.010 M in Ca(NO3)2. Will a precipitate form in the mixed solution? If so, identify the precipitate.
Calculate the concentration of Ag+ required to begin precipitation of Ag2CO3 in a solution that is 2.50 x 10–6 M in CO32−.
A solution containing potassium bromide is mixed with one containing lead acetate to form a solution that is 0.013 M in KBr and 0.0035 M in Pb(C2H3O2)2.Will a precipitate form in the mixed solution? If so, identify the precipitate.
The concentration of Mg2+ in seawater is 0.052 M. At what pH will 99% of the Mg 2+ be precipitated as the hydroxide salt? [Ksp for Mg(OH)2 = 8.9 X 10 -12.]
Potassium hydroxide is used to precipitate each of the cations from their respective solution. Determine the minimum concentration of KOH required for precipitation to begin in each case.2.6×10−3 M Fe(NO3)2
What [Ag+] is required to reduce [CO32−] to 8.2 × 10–4 M by precipitation of Ag2CO3?
A solution of 0.075 M CoBr2 is saturated with H2S ([H2S] = 0.10 M). What is the minimum pH at which CoS begins to precipitate?CoS(s) ⇌ Co2+(aq) + S2−(aq)           Ksp = 4.5 × 10−27H2S(aq) + 2H2O(l) ⇌ 2H3O+(aq) + S2−(aq)        K = 1.0 × 10−26
What [F–] is required to reduce [Ca2+] to 1.0 × 10–4 M by precipitation of CaF2?
A 0.125-M solution of Mn(NO3)2 is saturated with H2S ([H2S] = 0.10 M). At what pH does MnS begin to precipitate?MnS(s) ⇌ Mn2+(aq) + S2−(aq)                      Ksp = 4.3 × 10−22H2S(aq) + 2H2O(l) ⇌ 2H3O+(aq) + S2−(aq)              K = 1.0 × 10−26
Determine the minimum concentration of the precipitating agent on the right to cause precipitation of the cation from the solution on the left.4.0×10−2 M Ba(NO3)2; NaF
Will a precipitate form when 100.0 mL of 4.0 X 10 -4 M Mg(NO3)2 is added to 100.0 mL of 2.0 X 10 -4 M NaOH?
Determine the minimum concentration of the precipitating agent on the right to cause precipitation of the cation from the solution on the left.9.0×10−2 M CaI2; K2SO4
A volume of 0.800 L of a 2 × 10–4-M Ba(NO3)2 solution is added to 0.200 L of 5 × 10–4 M Li2SO4. Does BaSO4 precipitate? Explain your answer.
Determine the minimum concentration of the precipitating agent on the right to cause precipitation of the cation from the solution on the left.1.8×10−3 M AgNO3; RbCl
To a 0.10-M solution of Pb(NO3)2 is added enough HF(g) to make [HF] = 0.10 M.(a) Does PbF2 precipitate from this solution? Show the calculations that support your conclusion.
Consider a solution that is 1.3×10−2 M in Ba2+ and 2.0×10−2 M in Ca2+. What minimum concentration of Na2SO4 is required to cause the precipitation of the cation that precipitates first?
To a 0.10-M solution of Pb(NO3)2 is added enough HF(g) to make [HF] = 0.10 M.(b) What is the minimum pH at which PbF2 precipitates?
Consider a solution that is 1.3×10−2 M in Ba2+ and 2.0×10−2 M in Ca2+. What is the remaining concentration of the cation that precipitates first, when the other cation just begins to precipitate using Na2SO4?
Consider a solution that is 1.3×10−2 M in Ba2+ and 2.0×10−2 M in Ca2+. If sodium sulfate is used to selectively precipitate one of the cations while leaving the other cation in solution, which cation will precipitate first?
Consider a solution that is 2.3×10−2 M in Fe2+ and 1.6×10−2 M in Mg2+. What minimum concentration of K2CO3 is required to cause the precipitation of the cation that precipitates first?
A solution contains 1.0 X 10 -5 M Ag+ and 2.0 X 10 -6 M CN -. Will AgCN(s) precipitate? (Ksp for AgCN(s) is 2.2 X 10 -12.)
What mass of NaCN must be added to 1 L of 0.010 M Mg(NO3)2 in order to produce the first trace of Mg(OH)2?
Iron concentrations greater than 5.4 × 10–6 M in water used for laundry purposes can cause staining. What [OH–] is required to reduce [Fe2+] to this level by precipitation of Fe(OH)2?
A solution is prepared by mixing 100.0 mL of 1.0 X 10 -2 M Pb(NO3)2 and 100.0 mL of 1.0 X 10-3 M NaF. Will PbF2(s) (Ksp = 4 X 10 -8) precipitate?
A solution is 0.010 M in both Cu2+ and Cd2+. What percentage of Cd2+ remains in the solution when 99.9% of the Cu2+ has been precipitated as CuS by adding sulfide?
A solution is 0.15 M in both Pb2+ and Ag+. If Cl– is added to this solution, what is [Ag+] when PbCl2 begins to precipitate?
A solution contains 2.0 X 10 -3 M Ce3+ and 1.0 X 10 -2 M IO3 3-. Will Ce(IO3)3(s) precipitate? [Ksp for Ce(IO3)3 is 3.2 X 10-10.]
The following question is taken from a Chemistry Advanced Placement Examination and is used with the permission of the Educational Testing Service.Solve the following problem:MgF2(s) ⇌ Mg2+(aq) + 2F−(aq)In a saturated solution of MgF2 at 18°C, the concentration of Mg2+ is 1.21 × 10–3 M. The equilibrium isrepresented by the preceding equation.(c) Predict whether a precipitate of MgF2 will form when 100.0 mL of a 3.00 × 10–3-M solution of Mg(NO3)2 is mixed with 200.0 mL of a 2.00 × 10–3-M solution of NaF at 18°C. Show the calculations to support your prediction.
Predict whether or not a precipitate forms upon mixing 175.0 mL of a 0.0055 M solution with 145.0 mL of a 0.0015 M AgNO3 solution. Identify the precipitate, if any.
You have an aqueous solution of chromium(III) nitrate that you titrate with an aqueous solution of sodium hydroxide. After a certain amount of titrant has been added, you observe a precipitate forming. You add more sodium hydroxide solution and the precipitate dissolves, leaving a solution again. What has happened?
Under what conditions does an ionic compound precipitate from a solution of the constituent ions?
Gout-a condition that results in joint swelling and pain-is caused by the formation of sodium urate (NaC5H3N4) crystals within tendons, cartilage, and ligaments. Sodium urate will precipitate out of blood plasma when uric acid levels become abnormally high. This could happen as a result of eating too many rich foods and consuming too much alcohol, which is why gout is sometimes referred to as the "disease of kings."If the sodium concentration in blood plasma is 0.140 M, and Ksp for sodium urate is 5.76 x 10–8, what minimum concentration of urate would result in the precipitation of sodium urate?
Pseudogout, a condition with symptoms similar to those of gout (see previous problem), is caused by the formation of calcium diphosphate (Ca2P2O7) crystals within tendons, cartilage, and ligaments. Calcium diphosphate will precipitate out of blood plasma when diphosphate levels become abnormally high.If the calcium concentration in blood plasma is 9.2 mg/dL, and Ksp for calcium diphosphate is 8.64 x 10–13, what minimum concentration of diphosphate results in the precipitation of calcium diphosphate?
A solution contains 1.0 X 10 -5 M Na 3PO4. What is the minimum concentration of AgNO3 that would cause precipitation of solid Ag 3PO4 (Ksp = 1.8 X 10 -18)?
A volume of 50 mL of 1.8 M NH3 is mixed with an equal volume of a solution containing 0.95 g of MgCl2. What mass of NH4Cl must be added to the resulting solution to prevent the precipitation of Mg(OH)2?
An insoluble salt MX has a Ksp of 1.0  10-16. Two solutions, MNO3 and NaX are mixed, to yield a final solution that is 1.0  10-8 M in M+(aq) and 1.00  10-7 M in X-(aq). Will a precipitate form?
A solution is 1 X 10 -4 M in NaF, Na 2S, and Na3PO4. What would be the order of precipitation as a source of Pb2+ is added gradually to the solution? The relevant Ksp values are Ksp(PbF2) = 4 X 10 -8, Ksp(PbS) = 7 X 10 -29, and Ksp[Pb3(PO4)2] = 1 X 10 -54.
A solution contains 0.25 M Ni(NO3)2 and 0.25 M Cu(NO3)2. Can the metal ions be separated by slowly adding Na2CO3? Assume that for successful separation 99% of the metal ion must be precipitated before the other metal ion begins to precipitate, and assume no volume change on addition of Na2CO3.
Describe how you could separate the ion in the following group by selective precipitation.a. Ag+, Mg2+, Cu2+
Describe how you could separate the ion in the following group by selective precipitation.b. Pb2+, Ca2+, Fe2+
A 50.0-mL sample of 0.0413 M AgNO3(aq) is added to 50.0 mL of 0.100 M NaIO 3(aq). Calculate the [Ag+] at equilibrium in the resulting solution. [K sp for AgIO3(s) = 3.17 X 10 -8.]
The calcium ions in human blood serum are necessary for coagulation (Figure 15.5). Potassium oxalate, K2C2O4, is used as an anticoagulant when a blood sample is drawn for laboratory tests because it removes the calcium as a precipitate of CaC2O4•H2O. It is necessary to remove all but 1.0% of the Ca2+ in serum in order to prevent coagulation. If normal blood serum with a buffered pH of 7.40 contains 9.5 mg of Ca2+ per 100 mL of serum, what mass of K2C2O4 is required to prevent the coagulation of a 10 mL blood sample that is 55% serum by volume? (All volumes are accurate to two significant figures. Note that the volume of serum in a 10-mL blood sample is 5.5 mL. Assume that the Ksp value for CaC2O4 in serum is the same as in water.)
Describe how you could separate the ion in the following group by selective precipitation.c. Pb2+, Bi3+
Does any solid Cu(OH)2 form when 0.075 g of KOH is dissolved in 1.0 L of 1.0×10−3 M Cu(NO3)2?
Does any solid PbCl2 form when 3.5 mg of NaCl is dissolved in 0.250 L of 0.12 M Pb(NO3)2?
Does any solid Ba(IO3)2 form when 7.5 mg of BaCl2 is dissolved in 500. mL of 0.023 M NaIO3?
Does any solid Ag2CrO4 form when 2.7×10−5 g of AgNO3 is dissolved in 15.0 mL of 4.0×10−4 M K2CrO4?
Magnesium metal (a component of alloys used in aircraft and a reducing agent used in the production of uranium, titanium, and other active metals) is isolated from sea water by the following sequence of reactions:Mg2+(aq) + Ca(OH)2(aq) ⟶ Mg(OH)2(s) + Ca2+(aq)Mg(OH)2(s) + 2HCl(aq) ⟶ MgCl2(s) + 2H2O(l)Sea water has a density of 1.026 g/cm3 and contains 1272 parts per million of magnesium as Mg2+(aq) by mass.What mass, in kilograms, of Ca(OH)2 is required to precipitate 99.9% of the magnesium in 1.00 × 103 L of seawater?
Hydrogen sulfide is bubbled into a solution that is 0.10 M in both Pb2+ and Fe2+ and 0.30 M in HCl. After the solution has come to equilibrium it is saturated with H2S ([H2S] = 0.10 M). What concentrations of Pb2+ and Fe2+ remain in the solution? For a saturated solution of H2S we can use the equilibrium:H2S(aq) + 2H2O(l) ⇌ 2H3O+(aq) + S2−(aq)          K = 1.0 × 10  −26(Hint: The [H3O+] changes as metal sulfides precipitate.)
A solution containing lead(II) nitrate is mixed with one containing sodium bromide to form a solution that is 0.0150 M in Pb(NO3)2 and 0.00350 M in NaBr. If the solutions are concentrated through evaporation and mixed again to form a solution that is 0.0600 M in Pb(NO3)2 and 0.0158 M in NaBr, will a precipitate form in this newly mixed solution? (The value of Ksp for PbBr2 is 4.67 x 10–6)
A solution containing lead(II) nitrate is mixed with one containing sodium bromide to form a solution that is 0.0651 M in Pb(NO3)2 and 0.0151 M in NaBr. What is the value of Q for the insoluble product?
A solution is 0.025 M in Pb2+. What minimum concentration of Cl- is required to begin to precipitate PbCl2? For PbCl2, Ksp = 1.17 x 10–5.
The magnesium and calcium ions present in seawater ([Mg2+] = 0.026M and [Ca2+] = 0.011 M) can be separated by selective precipitation with KOH. What minimum [OH-] triggers the precipitation of the Mg2+ ion?
What mass of Ca(NO3)2 must be added to 1.0 L of a 1.0-M HF solution to begin precipitation of CaF2(s)? For CaF2, Ksp = 4.0 X 10 -11 and Ka for HF = 7.2 X 10 -4. Assume no volume change on addition of Ca(NO3)2(s).
A solution is 0.085 M in Pb2+ and 0.025 M in Ag+. If selective precipitation is to be achieved using NaCl, what minimum concentration of NaCl do you need to begin to precipitate the ion that precipitates first?
A solution is 0.085 M in Pb2+ and 0.025 M in Ag+. What is the concentration of each ion left in solution at the point where the second ion begins to precipitate if precipitation was done using NaCl?
Which of the following compounds precipitates from a solution that has the concentrations indicated? (See Appendix J for Ksp values.)(a) KClO4: [K+] = 0.01 M, [ClO4−] = 0.01 M(b) K2PtCl6: [K+] = 0.01 M, [PtCl62−] = 0.01 M(c) PbI2: [Pb2+] = 0.003 M, [I–] = 1.3 x 10–3 M(d) Ag2S: [Ag+] = 1 x 10–10 M, [S2–] = 1 x 10–13 M
Ammonium chloride, NH4Cl, is a very soluble salt in water. If you dissolve 14 g of ammonium chloride in 500.0 mL of water, how many grams of silver nitrate do you need to add to the solution to precipitate all of the chloride as silver chloride?
A solution contains 2.1×10−4 M  Ag+ and 1.6×10−3 M  Pb2 + .Specify the concentration of I- needed to begin precipitation.
Sodium sulfate is slowly added to a solution containing 0.0500 M Ca  2+ (aq) and 0.0320 M Ag+(aq). a) What will be the concentration of Ca 2+(aq) when Ag2SO4(s) begins to precipitate? b) What percentage of the Ca 2+(aq) can be precipitated from the Ag +(aq) by selective precipitation?
When 12.0 mL of a 6.38 x 10^-4 M manganese (II) sulfate solution is combined with 12.0mL of a 8.32 x 10^-4 M sodium hydroxide solution. For these conditions, the Reaction Quotient, Q, is equal to.
When 18.0 ml of a 2.19 x10-4 M lead acetate solution is combined with 12.0 mL of a 5.60 x 104 M ammonium fluoride solution does a precipitate form? For these conditions the Reaction Quotient, Q, in equal to ______
A solution is 5.0 x 10-5 M in each of these ions: Ag+, SO42-, Cl-, CO32- Which precipitate will form? (a) AgSO4 (Ksp = 1.12 x 10-5)(b) AgCl (Ksp = 1.77 x 10-10)(c) Ag2CO3 (Ksp = 8.46 x 10-12)