22. What is the maximum concentration of carbonate ions that will precipitate BaCO 3 but not MgCO 3 from a solution that is 2.

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1 PX What is the solubility product expression for Th(IO 3 ) 4? A) K sp = [Th 4+ ][4IO 3 ] 4 B) K sp = [Th 4+ ][IO 3 ] C) K sp = [Th][IO 3 ] 4 D) K sp = [Th 4+ ][IO 3 ] 4 E) K sp = [Th 4+ ][IO 3 ] 2. What is the solubility product expression for La 2 (CO 3 ) 3? A) K sp = [2La 3+ ] 2 [3CO 3 2 ] 3 B) K sp = [La 2+ ] 2 [CO 3 2 ] 3 C) K sp = [2La 3+ ] 2 [CO 3 2 ] 3 D) K sp = [2La 3+ ][3CO 3 2 ] E) K sp = [La 3+ ] 2 [CO 3 2 ] 3 3. After mixing an excess PbCl 2 with a fixed amount of water, it is found that the equilibrium concentration of Pb 2+ is M. What is K sp for PbCl 2? A) B) C) D) E) The solubility of lead(ii) sulfate is g/l. What is the solubility product constant for lead(ii) sulfate? A) B) C) D) E) The silver-ion concentration in a saturated solution of silver(i) chromate is M. What is K sp for silver(i) chromate? A) B) C) D) E) Which of the following salts has the lowest molar solubility? A) SrCO 3 (K sp = ) B) MnS (K sp = ) C) BaF 2 (K sp = ) D) BaSO 4 (K sp = ) E) AgCl (K sp = )

2 7. Rank the following metal sulfides in order of increasing molar solubility in water. Salt K sp CoS CuS FeS HgS MnS A) MnS < FeS < CoS < CuS < HgS B) FeS < HgS < CoS < CuS < MnS C) HgS < CuS < CoS < FeS < MnS D) CuS < CoS < FeS < MnS < HgS E) CoS < CuS < FeS < HgS < MnS 8. What is the molar solubility of calcium sulfate at 25 C? The solubility product constant for calcium sulfate is at 25 C. A) M B) M C) M D) M E) M 9. What is the molar solubility of barium fluoride at 25 C? The solubility product constant for barium fluoride is at 25 C. A) M B) M C) M D) M E) M 10. What is the ph of a saturated solution of Ni(OH) 2? For Ni(OH) 2, K sp = A) 4.80 B) 8.90 C) 5.10 D) 9.20 E) The insoluble salts AV, B 2 W, C 2 X 3, DY 2, and EZ 3, which were formed from the metal ions A +, B +, C 3+, D 2+, and E 3+ and the nonmetals V 1, W 2, X 2, Y 1, and Z 1, all have the same K sp value. Which salt has the highest molar solubility? A) AV B) EZ 3 C) DY 2 D) B 2 W E) C 2 X 3

3 12. In which of these solutions would silver(i) carbonate have the lowest molar solubility? For silver(i) carbonate, K sp = A) 0.03 M H 2 CO 3 B) 0.1 M AgNO 3 C) 0.01 M AgNO 3 D) 0.1 M Na 2 CO 3 E) pure water 13. What is the concentration of silver(i) ion in a saturated solution of silver(i) carbonate containing M Na 2 CO 3? For Ag 2 CO 3, K sp = A) M B) M C) M D) M E) M 14. What is the molar solubility of MgF 2 in a 0.40 M Mg(NO 3 ) 2 solution? For MgF 2, K sp = A) M B) M C) M D) M E) M 15. The solubility of La(IO 3 ) 3 in a 0.62 M KIO 3 solution is mol/l. Calculate K sp for La(IO 3 ) 3. A) B) C) D) E) none of these 16. How many moles of CaF 2 will dissolve in 3.0 L of M NaF solution? (K sp for CaF 2 = ) A) B) C) D) E) none of these 17. Which of Figures I IV represent(s) the result of mixing aqueous solutions of Na 2 S and NiCl 2 in which the ion product Q c > K sp for the insoluble product? (C = cation, A = anion)

4 A) both I and II B) only I C) only II D) only III E) only IV 18. Which of the following will apply to a saturated solution of an ionic compound? A) Q c < K sp B) Q c > K sp C) Q c = K sp D) K sp = 1 E) Q c = To 1.0 L of water, mol of Pb(NO 3 ) 2, mol of K 2 CrO 4, and 1.0 mol of NaCl are added. What will happen? Salt K sp PbCrO PbCl A) A precipitate of KCl will form. B) A precipitate of PbCrO 4 will form. C) A precipitate of PbCl 2 will form. D) No precipitate will form. E) Both a precipitate of PbCl 2 and a precipitate of PbCrO 4 will form. 20. What will happen if 0.1 mol of solid silver(i) nitrate is added to 1.0 L of a saturated solution of silver(i) chromate? For Ag 2 CrO 4, K sp = A) The AgNO 3 will settle to the bottom without dissolving. B) The concentration of CrO 4 2 will increase. C) Some Ag 2 CrO 4 will precipitate. D) Nothing will happen. E) The concentration of Ag + in solution will not change. 21. What is the minimum mass of Na 2 CO 3 that must be added to 24.6 ml of a M AgNO 3 solution in order for precipitation to occur? For Ag 2 CO 3, K sp = A) g B) g

5 C) g D) g E) g 22. What is the maximum concentration of carbonate ions that will precipitate BaCO 3 but not MgCO 3 from a solution that is M each in Mg 2+ and Ba 2+? For MgCO 3, K sp = and for BaCO 3, K sp = A) M B) M C) M D) M E) M 23. Which of the following solutions should be added to a solution containing both copper(ii) ions and silver(i) ions in order to precipitate only one of the ions? A) HCl(aq) B) H 2 S(aq) C) HNO 3 (aq) D) H 2 S(aq) + HCl(aq) E) H 2 S(aq) + HNO 3 (aq) 24. For which pair of cations would the addition of dilute hydrobromic acid precipitate one but not the other? A) Ag + and Ca 2+ B) Hg 2 2+ and Ag + C) Ba 2+ and Na + D) Ca 2+ and Ba 2+ E) Pb 2+ and Ag Sodium chloride is added slowly to a solution that is M in Cu +, Ag +, and Au +. The K sp values for the chloride salts are , , and , respectively. Which compound will precipitate first? A) AuCl(s) B) All will precipitate at the same time. C) It cannot be determined. D) AgCl(s) E) CuCl(s) 26. Solid KCN is added to a solution composed of 0.10 M Ag + and 0.10 M Zn 2+ just until a precipitate forms. What is the composition of this initial precipitate? AgCN K sp = and Zn(CN) 2 K sp = A) The precipitate is pure AgCN(s). B) The precipitateis pure Zn(CN) 2 (s). C) The precipitate is a mixture of AgCN(s) and Zn(CN) 2 (s). D) The precipitate is a mixture of KCN(s) and AgCN(s). E) The precipitate is a mixture of KCN(s) and Zn(CN) 2 (s).

6 27. Suppose hydrogen sulfide is added to a solution that is M in Fe 2+, Cd 2+, Co 2+, and Mn 2+ such that the concentration of H 2 S is 0.10 M. When the ph of the solution is adjusted to 3, a precipitate forms. What is the composition of the precipitate? H 2 S(aq) + 2H 2 O(l) 2H 3 O + (aq) + S 2 (aq); K c = Salt K sp FeS CdS CoS MnS A) CdS only B) CdS, CoS, FeS, and MnS C) CdS, CoS, and FeS D) CdS and FeS E) CdS and CoS 28. Suppose sodium hydroxide is added to a M solution of zinc nitrate such that the ph of the solution is What is the equilibrium concentration of Zn 2+? Zn 2+ (aq) + 4OH (aq) Zn(OH) 4 2 (aq); K f = A) M B) M C) M D) M E) M 29. In the sulfide scheme for qualitative analysis, the cations of Analytical Group IV are precipitated as phosphates or carbonates. Analytical Group IV consists of A) alkaline earth elements. B) the halogens. C) alkali metals. D) transition metals having +2 ions. E) none of these 30. Consider a solution containing the following cations: Na +, Hg 2+, Mn 2+, Al 3+ and Ag +. Treatment of the solution with dilute, HCl followed by saturation with H 2 S, results in formation of precipitate(s). Which ions still remain in solution (did not precipitate)? A) Na +, Hg 2+, Al 3+ B) Na + only C) Ag + and Hg 2+ D) Ag + only E) Na +, Al 3+, and Mn The following reaction represents a step in the separation of which analytical group of cations? Cu 2+ (aq) + S 2 (aq) CuS(s)

7 A) Analytical Group I B) Analytical Group III C) Analytical Group V D) Analytical Group IV E) Analytical Group II 32. Which of the following statements concerning entropy change is/are true? For a spontaneous process,. For a spontaneous process,. For an equilibrium process (such as a phase change),. A) 1 only B) 2 only C) 3 only D) 2 and 3 E) 1, 2, and The total entropy of a system and its surroundings always increases for a spontaneous process. This is a statement of A) the third law of thermodynamics. B) the law of constant composition. C) the second law of thermodynamics. D) the law of conservation of matter. E) the first law of thermodynamics. 34. At the normal boiling point of o-xylene, H vap = 36.2 kj/mol and S vap = 86.7 J/(mol K). What is the normal boiling point of o-xylene? A) 314 K B) 373 K C) 115 K D) 867 K E) 418 K 35. Which of the following is not a spontaneous process at 25 C and 1 atm pressure? A) salt dissolving B) ice melting C) water boiling D) iron rusting E) steam condensing 36. For the process Cl 2 (g) 2Cl(g), A) H is + and S is + for the reaction. B) H is + and S = 0 for the reaction. C) H is and S is for the reaction.

8 D) H is and S is + for the reaction. E) H is + and S is for the reaction. 37. What is the change in entropy when g of water decomposes to form hydrogen gas and oxygen gas at 298 K? 2H 2 O(l) 2H 2 (g) + O 2 (g); S = J/K at 298 K A) 5.85 J/K B) J/K C) 23.4 J/K D) 11.7 J/K E) 211 J/K 38. Determine G for the following reaction: CH 4 (g) + 2O 2 (g) CO 2 (g) + 2H 2 O(l) Substance G f (kj/mol) CH 4 (g) O 2 (g) 0 CO 2 (g) H 2 O(l) A) kj B) kj C) kj D) kj E) kj 39. Based on the following data, what is the standard Gibbs free energy of formation of the sulfate ion at 298 K? (R = 8.31 J/(K mol)) CaSO 4 (s) Ca 2+ (aq) + SO 4 2 (aq); K sp = Substance G f (kj/mol) at 298 K Ca 2+ (aq) CaSO 4 (s) A) kj/mol B) kj/mol C) kj/mol D) kj/mol E) kj/mol 40. A certain reaction is found to be product favored. Which of the following is a correct description of the reaction? A) G < 0, K > 1 B) G > 0, K < 1 C) G > 0, K > 1 D) G < 0, K < 1

9 E) G = 0, K > The standard free energy of formation of nitric oxide, NO, at K (roughly the temperature in an automobile engine during ignition) is 78.0 kj/mol. Calculate the equilibrium constant for the reaction 2NO(g) at K. (R = 8.31 J/(K mol)) A) 0.95 B) C) D) 15 E) Consider the following hypothetical reaction (at K). Standard free energies, in kj/mol, are given in parentheses. A B + C G =? ( 32.2) (207.8) ( 237.0) What is the value of the equilibrium constant for the reaction at K? A) 0.42 B) 1.0 C) 273 D) E) A M solution of a particular monoprotic weak acid, HA, has a ph of 6.00 at 298 K. What is G for the following equilibrium? HA(aq) + H 2 O(l) A) 28.5 kj B) 34.2 kj C) 620 kj D) 5.71 kj E) 62.7 kj H 3 O + (aq) + A (aq) 44. The reaction CaO(s) + SO 3 (g) CaSO 4 (s) is nonspontaneous at 2200 K, whereas it is spontaneous at room temperature. Which of the following statements is false? A) The change in enthalpy is the main driving force of the reaction. B) Both H and S are negative for the reaction. C) G is negative at room temperature. D) The change in entropy is the main driving force of the reaction. E) G becomes zero at a temperature between 300 and 2200 K. 45. For the reaction CaCO 3 (s) CaO(s) + O 2 (g) at 1 atm pressure, the values of H and S are both positive, and the process is spontaneous at high temperatures. Which of the following statements about this reaction is true?

10 A) The change in entropy is the driving force for the reaction. B) The process is exothermic at high temperatures and endothermic at room temperature. C) The reverse reaction is endothermic. D) The reverse reaction is nonspontaneous at room temperature. E) G at room temperature is negative. 46. Which of the following statements is true concerning the reaction below? CH 4 (g) + N 2 (g) HCN(g) + NH 3 (g); H = kj; G = kj at 298 K A) It is nonspontaneous at all temperatures. B) It is spontaneous at relatively low temperatures only. C) It is spontaneous at all temperatures. D) It is at equilibrium at 298 K. E) It is spontaneous at relatively high temperatures only. 47. Which of the following statements is true for the following reaction? NH 4 HS(s) NH 3 (g) + H 2 S(g); H = 93 kj A) The reaction is not spontaneous at any temperature. B) The reaction is spontaneous only at relatively high temperatures. C) The reaction is at equilibrium under standard-state conditions. D) The reaction is spontaneous at all temperatures. E) The reaction is spontaneous only at relatively low temperatures. 48. Sublimation is an example of a process for which A) H is positive and S is negative at all temperatures. B) H is negative and S is positive at all temperatures. C) H, S, and G are negative at all temperatures. D) H and S are positive at all temperatures. E) H, S, and G are positive at all temperatures. 49. For the reaction G 700K = kj. What is K p for this reaction at 700. K? A) 1.00 B) 1.54 C) 10.1 D) 2.31 E) none of these 50. Consider the following reaction: 2C(s) + 3H 2 (g) C 2 H 6 (g); H = kj; S = J/K at 298 K What is the equilibrium constant at K for this reaction? A) B) C) 1.0

11 D) E)

12 PX Answer Section 1. ANS: D PTS: 1 DIF: easy REF: 17.1 OBJ: Write solubility product expressions. (Example 17.1) KEY: solubility product constant 2. ANS: E PTS: 1 DIF: easy REF: 17.1 OBJ: Write solubility product expressions. (Example 17.1) KEY: solubility product constant 3. ANS: B PTS: 1 DIF: moderate REF: 17.1 OBJ: Calculate Ksp from the solubility (more complicated example).(example 17.3) KEY: solubility product constant 4. ANS: A PTS: 1 DIF: moderate REF: 17.1 OBJ: Calculate Ksp from the solubility (more complicated example).(example 17.3) KEY: solubility product constant 5. ANS: D PTS: 1 DIF: difficult REF: 17.1 OBJ: Calculate Ksp from the solubility (more complicated example).(example 17.3) KEY: solubility product constant 6. ANS: D PTS: 1 DIF: easy REF: 17.1 OBJ: Calculate the solubility from Ksp. (Example 17.4) KEY: solubility product constant relative solubilities 7. ANS: C PTS: 1 DIF: easy REF: 17.1 OBJ: Calculate the solubility from Ksp. (Example 17.4) KEY: solubility product constant relative solubilities 8. ANS: E PTS: 1 DIF: easy REF: 17.1 OBJ: Calculate the solubility from Ksp. (Example 17.4) KEY: solubility product constant 9. ANS: A PTS: 1 DIF: easy REF: 17.1 OBJ: Calculate the solubility from Ksp. (Example 17.4) KEY: solubility product constant 10. ANS: D PTS: 1 DIF: moderate REF: 17.1 OBJ: Calculate the solubility from Ksp. (Example 17.4) KEY: solubility product constant 11. ANS: E PTS: 1 DIF: difficult REF: 17.1 OBJ: Calculate the solubility from Ksp. (Example 17.4)

13 KEY: solubility product constant relative solubilities 12. ANS: B PTS: 1 DIF: easy REF: 17.2 OBJ: Explain how the solubility of a salt is affected by another salt that has the same cation or anion (common ion). KEY: solubility and the common-ion effect MSC: general chemistry 13. ANS: D PTS: 1 DIF: moderate REF: 17.2 OBJ: Calculate the solubility of a slightly soluble salt in a solution of a common ion. (Example 17.5) KEY: solubility and the common-ion effect MSC: general chemistry 14. ANS: B PTS: 1 DIF: moderate REF: 17.2 OBJ: Calculate the solubility of a slightly soluble salt in a solution of a common ion. (Example 17.5) KEY: solubility and the common-ion effect MSC: general chemistry 15. ANS: D PTS: 1 DIF: moderate REF: 17.2 OBJ: Calculate the solubility of a slightly soluble salt in a solution of a common ion. (Example 17.5) KEY: solubility and the common-ion effect MSC: general chemistry 16. ANS: C PTS: 1 DIF: moderate REF: 17.2 OBJ: Calculate the solubility of a slightly soluble salt in a solution of a common ion. (Example 17.5) KEY: solubility and the common-ion effect MSC: general chemistry 17. ANS: D PTS: 1 DIF: moderate REF: 17.3 OBJ: State the criterion for precipitation. KEY: precipitation calculations 18. ANS: C PTS: 1 DIF: easy REF: 17.3 OBJ: State the criterion for precipitation. KEY: precipitation calculations criterion for precipitation 19. ANS: B PTS: 1 DIF: easy REF: 17.3 OBJ: Predict whether precipitation will occur (given ion concentrations). (Example 17.6) KEY: precipitation calculations criterion for precipitation 20. ANS: C PTS: 1 DIF: easy REF: 17.3 OBJ: Predict whether precipitation will occur (given ion concentrations). (Example 17.6) KEY: precipitation calculations criterion for precipitation 21. ANS: E PTS: 1 DIF: moderate REF: 17.3 OBJ: Predict whether precipitation will occur (given solution volumes and concentrations). (Example 17.7)

14 KEY: precipitation calculations criterion for precipitation 22. ANS: A PTS: 1 DIF: moderate REF: 17.3 OBJ: Explain how two ions can be separated using fractional precipitation. KEY: precipitation calculations fractional precipitation 23. ANS: A PTS: 1 DIF: easy REF: 17.3 OBJ: Explain how two ions can be separated using fractional precipitation. KEY: precipitation calculations fractional precipitation 24. ANS: A PTS: 1 DIF: easy REF: 17.3 OBJ: Explain how two ions can be separated using fractional precipitation. KEY: precipitation calculations fractional precipitation 25. ANS: A PTS: 1 DIF: moderate REF: 17.3 OBJ: Explain how two ions can be separated using fractional precipitation. KEY: precipitation calculations fractional precipitation 26. ANS: A PTS: 1 DIF: moderate REF: 17.3 OBJ: Explain how two ions can be separated using fractional precipitation. 27. ANS: E PTS: 1 DIF: difficult REF: 17.4 OBJ: Explain the basis for the sulfide scheme to separate a mixture of metal ions. KEY: effect of ph on solubility 28. ANS: D PTS: 1 DIF: moderate REF: 17.5 OBJ: Calculate the concentration of a metal ion in equilibrium with a complex ion. (Example 17.9) TOP: solubility complex ion equilibria KEY: complex ion formation equilibrium calculations with Kf 29. ANS: A PTS: 1 DIF: moderate REF: 17.7 OBJ: Describe the main outline of the sulfide scheme for qualitative analysis. TOP: solubility applications of solubility equilibria KEY: qualitative analysis of metal ions 30. ANS: E PTS: 1 DIF: moderate REF: 17.7 OBJ: Describe the main outline of the sulfide scheme for qualitative analysis. TOP: solubility applications of solubility equilibria KEY: qualitative analysis of metal ions 31. ANS: E PTS: 1 DIF: easy REF: 17.7 OBJ: Describe the main outline of the sulfide scheme for qualitative analysis. TOP: solubility applications of solubility equilibria KEY: qualitative analysis of metal ions 32. ANS: E PTS: 1 DIF: easy REF: 18.2 OBJ: Entropy. 33. ANS: C PTS: 1 DIF: easy REF: 18.2 OBJ: State the second law of thermodynamics in terms of system plus surroundings..

15 KEY: second law of thermodynamics entropy 34. ANS: E PTS: 1 DIF: easy REF: 18.2 OBJ: Calculate the entropy change for a phase transition. (Example 18.1) KEY: second law of thermodynamics entropy change for a phase transition 35. ANS: C PTS: 1 DIF: easy REF: 18.2 OBJ: Describe how deltah TdeltaS functions as a criterion of a spontaneous reaction. KEY: second law of thermodynamics entropy and molecular disorder 36. ANS: A PTS: 1 DIF: moderate REF: 18.3 OBJ: Predict the sign of the entropy change of a reaction. (Example 18.2) 37. ANS: A PTS: 1 DIF: easy REF: 18.3 OBJ: Calculate deltas for a reaction. (Example 18.3) KEY: third law of thermodynamics entropy change for a reaction 38. ANS: B PTS: 1 DIF: easy REF: 18.4 OBJ: Calculate deltag from standard free energies of formation. (Example 18.5) KEY: free energy standard free-energies of formation 39. ANS: D PTS: 1 DIF: difficult REF: 18.6 OBJ: Give the relation between free energy change of a reaction and the reaction quotient. KEY: free energy 40. ANS: A PTS: 1 DIF: easy REF: 18.6 OBJ: Relate the standard free-energy change to the thermodynamic equilibrium constant. 41. ANS: B PTS: 1 DIF: easy REF: 18.6 OBJ: Calculate K from the standard free-energy change (molecular equation). (Example 18.8) KEY: thermodynamic equilibrium constant (K) 42. ANS: E PTS: 1 DIF: moderate REF: 18.6 OBJ: Calculate K from the standard free-energy change (molecular equation). (Example 18.8) KEY: thermodynamic equilibrium constant (K) 43. ANS: E PTS: 1 DIF: difficult REF: 18.6 OBJ: Calculate K from the standard free-energy change (molecular equation). (Example 18.8) KEY: thermodynamic equilibrium constant (K) 44. ANS: D PTS: 1 DIF: easy REF: 18.7 OBJ: Describe the how spontaneity or nonspontaneity of a reaction is related to each of the four possible choices of signs of deltah and deltas.

16 KEY: temperature dependence of free energy spontaneity and temperature change 45. ANS: A PTS: 1 DIF: easy REF: 18.7 OBJ: Describe the how spontaneity or nonspontaneity of a reaction is related to each of the four possible choices of signs of deltah and deltas. KEY: temperature dependence of free energy spontaneity and temperature change 46. ANS: E PTS: 1 DIF: moderate REF: 18.7 OBJ: Describe the how spontaneity or nonspontaneity of a reaction is related to each of the four possible choices of signs of deltah and deltas. KEY: temperature dependence of free energy spontaneity and temperature change 47. ANS: B PTS: 1 DIF: moderate REF: 18.7 OBJ: Describe the how spontaneity or nonspontaneity of a reaction is related to each of the four possible choices of signs of deltah and deltas. KEY: temperature dependence of free energy spontaneity and temperature change 48. ANS: D PTS: 1 DIF: moderate REF: 18.7 OBJ: Describe the how spontaneity or nonspontaneity of a reaction is related to each of the four possible choices of signs of deltah and deltas. KEY: temperature dependence of free energy spontaneity and temperature change 49. ANS: C PTS: 1 DIF: easy REF: 18.7 OBJ: Calculate deltag and K at various temperatures. (Example 18.10) KEY: temperature dependence of free energy 50. ANS: D PTS: 1 DIF: difficult REF: 18.7 OBJ: Calculate deltag and K at various temperatures. (Example 18.10) KEY: temperature dependence of free energy