Unit 3 - Solubility Practice Test # 2

Transcription

1 1. onsider the following experiment: Unit 3 Solubility Practice Test # ml 0.20 M g + + an unknown solution precipitate 1.0 ml 020 M Sr 2+ + an unknown solution no precipitate The unknown solution could contain 0.20 M OH 0.20 M NO M PO M SO compound has a solubility of 7.1 x 10 5 M at 25 o. The compound is us gr ao 3 aso 4 3. saturated solution of Nal contains 36.5 g of solute in L of solution. The solubility of the compound is M 1.60 M 3.65 M 6.24 M 4. alculate the [Li + ] in ml of 1.5 M Li 2 SO M 0.60 M 1.5 M 3.0 M 5. The Ksp expression for a saturated solution of Mg(OH) 2 is Ksp = [Mg 2+ ][OH ] 2 Ksp = [Mg 2+ ][OH ] [Mg(OH) 2 ] Ksp = [Mg 2+ ][OH ] 2 Ksp = [Mg 2+ ][2OH ] 2 6. onsider the following saturated solution solutions uso 4 aso 4 aso 4 The order of cation concentration, from highest to lowest, is [a 2+ ] > [a 2+ ] > [u 2+ ] [a 2+ ] > [u 2+ ] > [a 2+ ] [u 2+ ] > [a 2+ ] > [a 2+ ] [u 2+ ] > [a 2+ ] > [a 2+ ] 1

2 7. When 1.0 x 10 3 moles of ul 2(s) are added to 1.0 L of 1.0 x 10 3 M IO 3, the Trial Ksp > Ksp and a precipitate forms Trial Ksp < Ksp and a precipitate forms Trial Ksp > Ksp and no precipitate forms Trial Ksp < Ksp and no precipitate forms 8. The solubility of ds = 2.8 x The value of the Ksp is 7.8 x x x x The ion concentrations in 0.25 M l 2 (SO 4 ) 3 are [l 3+ ] [SO 4 2 ] 0.25 M 0.25 M 0.50 M 0.75 M 0.75 M 0.50 M 0.10 M 0.15 M 10. Which of the following will not produce a precipitate when equal volumes of 0.20 M solutions are combined? KOH and al 2 Sr(OH) 2 and (NH 4 ) 2 S Zn(NO 3 ) 2 and K 3 PO 4 Na 2 SO 4 and Pb(NO 3 ) onsider the following equilibrium: Mg(OH) 2(s) Mg 2+ (aq) + 2OH (aq) compound that can be added to cause a shift to the right is NaOH Hl Sr(OH) 2 Mg(OH) If the trial ion product for gro 3 is calculated to be 1.0 x 10 7, then a precipitate forms because the trial ion product > Ksp a precipitate forms because the trial ion product < Ksp no a precipitate forms because the trial ion product > Ksp no a precipitate forms because the trial ion product < Ksp 13. Which of the following will dissolve in water to produce a molecular solution? al 2 NaOH H 3 OH Sr(OH) In a solubility equilibrium, the rate of dissolving equals the rate of crystallization neither dissolving or crystallization occurs concentration of solute and solvent are equal mass of dissolved solute is greater than the mass of the solution 2

3 15. The maximum [SO 4 2 ] that can exist in 1.0 x 10 3 M a(no 3 ) 2 without a precipitate forming is 7.1 x 10 5 M 1.0 x 10 3 M 8.4 x 10 3 M 7.1 x 10 2 M 16. When equal volumes of 0.20 M uso 4(aq) and 020 M Li 2 S (aq) are combined, the complete ionic equation is u 2+ (aq) + S 2 (aq) u S(s) uso 4(aq) + Li 2 S (aq) us (s) + Li 2 SO 4(s) u 2+ 2 (aq) + SO 4 (aq) + 2Li + (aq) + S 2 (aq) Li 2 SO 4(aq) + us (s) u 2+ 2 (aq) + SO 4 (aq) + 2Li (aq) + S 2 (aq) us (s) + 2Li + (aq) + S O 4 2 (aq) 17. onsider the solubility equilibrium: ao 3(aq) a 2+ (aq) + O 3 2 (aq) n additional piece of solid ao 3 is added to the equilibrium above. The rate of dissolving and the rate of crystallization have Rate of issolving Rate of crystallization increases increases increases not changed not changed increased not changed not changed 18. t 25 o, which of the following compounds would dissolve to form a saturated solution with the greatest [Pb 2+ ]? PbI 2 Pbl 2 Pbr 2 Pb(IO 3 ) onsider the following anions: I 10.0 ml of 0.20 M l II 10.0 ml of 0.20 M OH 2 III 10.0 ml of 0.20 M SO 3 When 10.0 ml of 0.20 M Pb(NO 3 ) 2 are added to each of the above, precipitates form in I and II only I and III only II and III only I, II, and III 20. Which of the following units could be used to describe solubility? g/s g/l M/L mol/s 21. The solubility of SnS is 3.2 x 10 3 M. The value of the Ksp is 1.0 x x x x

4 22. Silver chloride, gl, would be least soluble in 1.0 M Hl 1.0 M NaNO M Znl M gno The solubility of SrF 2 is 4.3 x x x x The Ksp expression for a saturated solution of go 3 is Ksp = [g 2 + ][O 3 2 ] Ksp = [g + ] 2 [O 3 2 ] Ksp = [2g + ][O 3 2 ] Ksp = [2g + ] 2 [O 3 2 ] 25. How many moles of solute are dissolved in ml of a saturated solution of FeS? 1.2 x x x x solution contains both g + and Mg 2+ ions. uring selective precipitation, these ions are removed one at a time by adding I followed by OH SO 4 followed by l OH followed by S 2 NO 3 3 followed by PO Which of the following does not define solubility? the concentration of solute in a saturated solution the moles of solute dissolved in a given amount of solution the maximum mass of solute that can dissolve in a given amount of solution the minimum amount of solute required to produce one litre of saturated solution 28. The ion concentrations in 0.25 M l 2 (SO 4 ) 3 are [l 3+ ] [SO 4 2 ] 0.25 M 0.25 M 0.50 M 0.75 M 0.75 M 0.50 M 0.10 M 0.15 M 29. Which of the following will not produce a precipitate when equal volumes of 0.20 M solutions are combined? KOH and Srl 2 Zn(OH) 2 and K 3 PO 4 Zn(OH) 2 and (NH 4 ) 2 S Na 2 SO 4 and Pb(NO 3 ) What is observed when H 2 SO 4 is added to a saturated solution of aso 4? aso 4(s) dissolves the [a 2+ ] increases bubbles of H 2 are given off additional aso 4 precipitates 4

5 31. The solubility of ds is 2.8 x M. The value of the Ksp is 7.8 x x x x onsider the following solutions: 0.10 M l 0.10 M r 0.10 M IO M ro 3 Equal moles of gno 3 are added to each solution. It is observed that a precipitate forms in all but one solution. Which solution does not form a precipitate? l IO 3 r ro onsider the following equilibrium: 2O 3(g) 3O 2(g) Keq = 65 Initially, 0.10 mole O 3 and 0.10 mole of O 2 are placed in a 1.0 L container. Which of the following describes the changes in concentrations as the reaction proceeds to equilibrium? [O 3 ] [O 2 ] decreases decreases decreases increases increases decreases increases increases 35. Increasing the temperature of a reaction increases the rate by I II III increasing frequency of collision increasing the kinetic energy of collision decreasing the potential energy of collision I only I and II only II and III only I, II, and III 36. What is the Keq expression for the following equilibrium? Fe (s) + 4H 2 O (g) Fe 3 O 4(s) + 4H 2(g) Keq = [H 2 ] 4 Keq = [H 2 ] 4 [H 2 O] 4 Keq = [H 2 ] Keq = [Fe 3 O 4 ][H 2 ] 4 [H 2 O] [Fe] 3 [H 2 O] 4 1. Write the net ionic equation representing the reaction that occurs when 50.0 ml of 0.20 M ZnSO 4 and 50.0 ml 0.20 M as are combined. 5

6 ml sample of 0.600M a(no 3 ) 2 is diluted by adding ml of water. alculate the concentrations of all of the ions. 3. When 1.00 L of af 2 was evaporated to dryness, 2.66 x 10 2 g of residue was formed. alculate the Ksp. 4. maximum of 0.60 g Pb(NO 3 ) 2 can be added to 1.5 L of Nar (aq) without forming a precipitate. alculate the [Nar]. 5. onsider the following solutions at 25 o Saturated gl (aq) Saturated g 2 O 3(aq) Using calculations, identify the solution with the greater [g + ]. 6

7 1. onsider the following experiment: NSWERS to the Practice Test #2 1.0 ml 0.20 M g + + an unknown solution precipitate 1.0 ml 020 M Sr 2+ + an unknown solution no precipitate The unknown solution could contain 0.20 M OH low with g + and high with Sr M NO M PO M SO 4 2. compound has a solubility of 7.1 x 10 5 M at 25 o. The compound is us gr ao 3 square the solubility aso 4 3. saturated solution of Nal contains 36.5 g of solute in L of solution. The solubility of the compound is M 1.60 M 3.65 M 6.24 M 4. alculate the [Li + ] in ml of 1.5 M Li 2 SO M 0.60 M 1.5 M 3.0 M o not divide by L 5. The Ksp expression for a saturated solution of Mg(OH) 2 is Ksp = [Mg 2+ ][OH ] 2 [Mg(OH) 2 ] Ksp = [Mg 2+ ][OH ] 2 Ksp = [Mg 2+ ][OH ] Ksp = [Mg 2+ ][2OH ] 2 7

8 6. onsider the following saturated solution solutions uso 4 aso 4 aso 4 The order of cation concentration, from highest to lowest, is [a 2+ ] > [a 2+ ] > [u 2+ ] [a 2+ ] > [u 2+ ] > [a 2+ ] [u 2+ ] > [a 2+ ] > [a 2+ ] largest to smallest Ksp [u 2+ ] > [a 2+ ] > [a 2+ ] 7. When 1.0 x 10 3 moles of ul 2(s) are added to 1.0 L of 1.0 x 10 3 M IO 3, the Trial Ksp > Ksp and a precipitate forms Trial Ksp < Ksp and a precipitate forms Trial Ksp > Ksp and no precipitate forms Trial Ksp < Ksp and no precipitate forms 8. The solubility of ds = 2.8 x M. The value of the Ksp is 7.8 x Square the solubility 2.8 x x x The ion concentrations in 0.25 M l 2 (SO 4 ) 3 are [l 3+ ] [SO 4 2 ] 0.25 M 0.25 M 0.50 M 0.75 M 0.75 M 0.50 M 0.10 M 0.15 M 10. Which of the following will not produce a precipitate when equal volumes of 0.20 M solutions are combined? KOH and al 2 Zn(NO 3 ) 2 and K 3 PO 4 Sr(OH) 2 and (NH 4 ) 2 S oth have high solubility Na 2 SO 4 and Pb(NO 3 ) onsider the following equilibrium: Mg(OH) 2(s) Mg 2+ (aq) + 2OH (aq) compound that can be added to cause a shift to the right is NaOH Hl cids react with OH 8

9 Sr(OH) 2 Mg(OH) If the trial ion product for gro 3 is calculated to be 1.0 x 10 7, then a precipitate forms because the trial ion product > Ksp a precipitate forms because the trial ion product < Ksp no a precipitate forms because the trial ion product > Ksp no a precipitate forms because the trial ion product < Ksp 13.Which of the following will dissolve in water to produce a molecular solution? al 2 NaOH H 3 OH One of these things is not kike the other Sr(OH) In a solubility equilibrium, the rate of dissolving equals the rate of crystallization neither dissolving or crystallization occurs concentration of solute and solvent are equal mass of dissolved solute is greater than the mass of the solution 15. The maximum [SO 4 2 ] that can exist in 1.0 x 10 3 M a(no 3 ) 2 without a precipitate forming is 7.1 x 10 5 M 1.0 x 10 3 M 8.4 x 10 3 M 7.1 x 10 2 M 16. When equal volumes of 0.20 M uso 4(aq) and 020 M Li 2 S (aq) are combined, the complete ionic equation is u 2+ (aq) + S 2 (aq) u S(s) uso 4(aq) + Li 2 S (aq) us (s) + Li 2 SO 4(s) u 2+ 2 (aq) + SO 4 (aq) + 2Li + (aq) + S 2 (aq) Li 2 SO 4(aq) + us (s) u 2+ (aq) 2 + SO 4 (aq) + 2Li (aq) + S 2 (aq) us (s) + 2Li + (aq) + S O 4 2 (aq) 17. onsider the solubility equilibrium: ao 3(aq) a 2+ (aq) + O 3 2 (aq) n additional piece of solid ao 3 is added to the equilibrium above. The rate of dissolving and the rate of crystallization have Rate of issolving Rate of crystallization increases increases increases not changed not changed increased not changed not changed 9

10 18. t 25 o, which of the following compounds would dissolve to form a saturated solution with the greatest [Pb 2+ ]? PbI 2 Pbl 2 largest Ksp Pbr 2 Pb(IO 3 ) onsider the following anions: I 10.0 ml of 0.20 M l II 10.0 ml of 0.20 M OH III ml of 0.20 M SO 3 When 10.0 ml of 0.20 M Pb(NO 3 ) 2 are added to each of the above, precipitates form in I and II only I and III only II and III only I, II, and III 20. Which of the following units could be used to describe solubility? g/s g/l M/L mol/s 21. The solubility of SnS is 3.2 x 10 3 M. The value of the Ksp is 1.0 x 10 5 square the solubility 3.2 x x x Silver chloride, gl, would be least soluble in 1.0 M Hl 1.0 M NaNO M Znl M gno The solubility of SrF 2 is 4.3 x x

11 1.0 x 10 3 squareroot the Ksp 1.6 x The Ksp expression for a saturated solution of go 3 is Ksp = [g 2 + ][O 3 2 ] Ksp = [g + ] 2 [O 3 2 ] Ksp = [2g + ][O 3 2 ] Ksp = [2g + ] 2 [O 3 2 ] 25. How many moles of solute are dissolved in ml of a saturated solution of FeS? 1.2 x x x x solution contains both g + and Mg 2+ ions. uring selective precipitation, these ions are removed one at a time by adding I followed by OH OH followed by S 2 SO 4 2 followed by l NO 3 followed by PO Which of the following does not define solubility? the concentration of solute in a saturated solution the moles of solute dissolved in a given amount of solution the maximum mass of solute that can dissolve in a given amount of solution the minimum amount of solute required to produce one litre of saturated solution 28. The ion concentrations in 0.25 M l 2 (SO 4 ) 3 are [l 3+ ] [SO 4 2 ] 0.25 M 0.25 M 0.50 M 0.75 M 0.75 M 0.50 M 0.10 M 0.15 M 29. Which of the following will not produce a precipitate when equal volumes of 0.20 M solutions are combined? KOH and Srl 2 Zn(OH) 2 and K 3 PO 4 Zn(OH) 2 and (NH 4 ) 2 S 11

12 Na 2 SO 4 and Pb(NO 3 ) What is observed when H 2 SO 4 is added to a saturated solution of aso 4? aso 4(s) dissolves the [a 2+ ] increases bubbles of H 2 are given off additional aso 4 precipitates 31. The solubility of ds is 2.8 x M. The value of the Ksp is 7.8 x x x x onsider the following solutions: 0.10 M l 0.10 M r 0.10 M IO M ro 3 Equal moles of gno 3 are added to each solution. It is observed that a precipitate forms in all but one solution. Which solution does not form a precipitate? l r IO 3 ro 3 highest Ksp 33. onsider the following equilibrium: 2O 3(g) 3O 2(g) Keq = 65 Initially, 0.10 mole O 3 and 0.10 mole of O 2 are placed in a 1.0 L container. Which of the following describes the changes in concentrations as the reaction proceeds to equilibrium? [O 3 ] [O 2 ] decreases decreases decreases increases increases decreases increases increases 34.onsider the following potential energy diagram for the reversible reaction. PE (KJ) Progress of the reaction 12

13 ctivation Energy (kj) ΔH (kj) Increasing the temperature of a reaction increases the rate by I II III increasing frequency of collision increasing the kinetic energy of collision decreasing the potential energy of collision I only I and II only II and III only I, II, and III 36. What is the Keq expression for the following equilibrium? Fe (s) + 4H 2 O (g) Fe 3 O 4(s) + 4H 2(g) Keq = [H 2 ] 4 Keq = [H 2 ] [H 2 O] Keq = [H 2 ] 4 [H 2 O] 4 Keq = [Fe 3 O 4 ][H 2 ] 4 [Fe] 3 [H 2 O] 4 13

14 Subjective 1. Write the net ionic equation representing the reaction that occurs when 50.0 ml of 0.20 M ZnSO 4 and 50.0 ml 0.20 M as are combined. ZnSO 4(aq) + as (aq) aso 4(s) + ZnS (s) Zn 2+ + SO a 2+ + S 2 aso 4(s) + ZnS (s) Zn 2+ + SO a 2+ + S 2 aso 4(s) + ZnS (s) ml sample of 0.600M a(no 3 ) 2 is diluted by adding ml of water. alculate the concentrations of all of the ions. a(no 3 ) 2 a NO 3 (100) M M M (500) 14

15 3. When 1.00 L of af 2 was evaporated to dryness, 2.66 x 10 2 g of residue was formed. alculate the Ksp. Molarity = 2.66 x 10 2 g x 1 mole 78.1 g = x 10 4 M 1.00 L af 2 a F x 10 4 M x 10 4 M x 10 4 M Ksp = (3.406 x 10 4 )(6.812 x 10 4 ) 2 = 1.58 x maximum of 0.60 g Pb(NO 3 ) 2 can be added to 1.5 L of Nar (aq) without forming a precipitate. alculate the [Nar]. Molarity = 0.60 g x 1 mole g = M 1.5 L 15

16 Pbr 2 Pb r M [r ] Ksp = [Pb 2+ ][r ] x 10 6 = [ ][r ] 2 [r ] = 7.4 x 10 2 M 5. onsider the following solutions at 25 o saturated gl (aq) saturated g 2 O 3(aq) Using calculations, identify the solution with the greater [g + ]. gl (s) g + + l g 2 O 3(s) 2g + + O 3 2 x x x x 2x x Ksp = x 2 Ksp = 4x x = x x = 4x 3 x = 1.3 x 10 5 M x = x 10 4 M [g + ] = 1.3 x 10 5 M [g + ] = 2x = 2.6 x 10 4 M Greater 16