Solubility Workbook Period Worksheets Quiz 1. Solubility and Saturated Solutions. WS 1 1 2. Ion Concentration Calculations and Ionic Equations. WS 2-3 2 3. Solubility to Ksp. WS 4 3 4. Ksp to Solubilty and Size of Ksp. WS 5 4 5. Trial Ksp. WS 6 5 6. Separating Ions WS 7 6 7. Common Ion Effect and WS 8 7 8. Titrations and Max Ion Concentration WS 9 8 9. Review Web Review Practice Test 1 10. Review Practice Test 2 11. Test The following workbook is designed to ensure that you can demonstrate your understanding of all aspects of the solubility unit. Ask yourself, “do I want to do well in this class?” If you are determined to be successful the minimum expectation that you should have for yourself is that you do all of these questions by the due dates given by your teacher. There are other things that you should do to prepare for the test at the end of the unit. Remember, what you put into this course is what you will get out. There is no substitute for consistent effort and hard work. If you can’t do a question, get some help before the end of the unit, you need to know, understand, and remember everything. Good luck! I know you can do well in this unit. Keep up the great work! Worksheet # 1 Solubility and Saturated Solutions 1. Define and give units for solubility. 2. Describe the relationship between the rate of dissolving and the rate of crystallization when a small amount of solute is added to an unsaturated solution. 3. Describe the relationship between the rate of dissolving and the rate of crystallization when a small amount of solute is added to a saturated solution. 4. Describe the relationship between the rate of dissolving and the rate of crystallization when a small amount of solute is added to a supersaturated solution. 5. Which of the above solutions would need to be prepared in order to determine the solubility of an ionic solution. 6. 2.65 g of Ba(OH)2 is dissolved in 70.0 mL of water to produce a saturated solution at 20 oC. Calculate the solubility in units of g/100 mL; g/L ; and M. 7. A beaker containing 100.0 mL of saturated BaCO3 solution weighs 159.60 g. The beaker is evaporated to dryness and weighs 56.36 g. The empty beaker weighs 24.33 g. Calculate the solubility in units of g/100 mL; g/ L; and M. 8. 9. Write dissociation equations to represent the equilibrium present for a saturated solution of each ionic compound. Write the solubility product (Ksp expression) for each of the equilibrium systems. The first one is done. a) Al2(SO4)3 b) FeCO3 c) Co2(SO4)3 d) Na3PO4 2Al3+ ⇄ SO42- + Ksp = [Al3+]2 [SO42-]3 Write formula, complete ionic, and net ionic equations for each. a) H2SO4(aq) + 2NaOH(aq) → Na2SO4 + 2HOH(l) 2H+ + SO42- + 2Na+ + 2OH- → 2Na+ + SO42- + 2HOH(l) H+ + OH- → HOH(l) b) Mg(NO3)2(aq) + Na2CO3(aq) → c) Al(NO3)3(aq) + (NH4)3PO4(aq) → d) H3PO4(aq) + Ca(OH)2(aq) → Worksheet # 2 Solubility 1. What is the concentration of each ion in a 10.5 M sodium silicate solution? 2. What is the concentration of each ion in the solution formed when 94.5 g of nickel (III) sulphate is dissolved into 850.0 mL of water? 3. If 3.78 L of 0.960 M sodium fluoride solution is added to 6.36 L of 0.550 M calcium nitrate solution, what is the resulting concentration of [Ca+2] and [F-]? 4. What is the concentration of each ion in the solution formed when 94.78 g of iron (III) sulphate is dissolved into 550.0 mL of water? 5. If the [F-] = 0.200 M, calculate the number of grams AlF3 that would be dissolved in 2.00 L of water. 6. If the [SO42-] = 0.200 M in 2.0 L of Al2(SO4)3, determine the [Al3+] and the molarity of the solution. Dissociation Equations Write dissociation equations for any chemicals, which dissociate when dissolved in water: 1. HCl (aq) → H+ 2. C6H12O6(S) → C6H12O6(aq) 3. Na2S (s) 4. Al(CH3COO)3 (s) 5. MgBr2 (s) 6. Na2CO3 (s) 7. C12H22O11 (s) 8. K3PO4 (s) 9. CH3OH (l) + Cl- ionic compounds dissociate molecular compounds do not dissociate Net Ionic Equations Write chemical equations, total ionic equations and net ionic equations for each reaction. The first one is done for you. (assume that all reactions occur): 1. Magnesium metal is placed in hydrochloric acid Mg (s) + 2 HCl (aq) → Mg (s) + 2 H+ (aq) + 2 Cl- (aq) → Mg (s) + 2 H+ (aq) → MgCl2 (aq) + H2 (g) Mg2+ (aq) + 2Cl- (aq) + H2 (g) Mg2+ (aq) + H2 (g) 2. Zinc metal is placed in silver nitrate solution 3. Barium chloride solution is added to lead (II) nitrate solution. 4. Sulphuric acid is added to strontium hydroxide solution. 5. Sodium carbonate solution is added to nickel (III) nitrate solution. 6. Aqueous chlorine is added to sodium bromide solution. 7. Nitric acid is added to strontium hydroxide solution. Worksheet # 3 1. Solubility Classify each as an ionic or molecular (covalent) solution. NaCl (aq) __________ CoCl2 (aq) _________ CH3OH (aq) ________ NH4OH (aq) ________ NH3 (aq) __________ AgCl (aq) _________ HCl (aq) __________ I2 (aq) ___________ 2. Define each: a) unsaturated solution: b) saturated solution: c) solubility: 3. Describe how you would prepare a saturated solution. 4. Describe how you would determine the solubility of NaCl in water at 20oC. 5. In terms of equilibrium describe the difference between a saturated and unsaturated solution. 6. What is the effect of temperature on solubility? 7. 200.0 g of CoCl2 is dissolved in 500.0 mL of water at 0oC to form a saturated solution. What is the solubility of CoCl2 at 0oC in three different units? 8. In a saturated solution of CaCl2, a small amount of solid is present. Write a net ionic equation showing the equilibrium reaction. Write the solubility product (Ksp expression) 9. If you were given a saturated, unsaturated and supersaturated solution, how would you distinguish one from another? a) Unsaturated solution: b) Saturated solution: c) Supersaturated solution: 10. Write the equilibrium equation and solubility product Ksp for each salt. The first one is done. a) Ca(OH)2 (s) → Ca2+ + 2OHKsp = [Ca2+] [OH-]2 b) AgCl (s) c) Na3PO4 (s) d) (NH4)3PO4 (s) e) Cu2SO4 (s) f) Al(CH3COO)3 (s) g) Ca3(PO4)2 (s) Worksheet # 4 Solubility to Ksp The Ksp is a measure of the solubility of an ionic salt. The larger the value of the Ksp, the greater is the solubility of the salt. You can only calculate a Ksp if the solution is saturated. Only saturated salt solutions are in equilibrium. You can calculate the Ksp from the solubility of a salt, since the solubility represents the concentration required to saturate a solution. 1. Calculate the Ksp for CaCl2 if 200.0g of CaCl2 is required to saturate 100.0 mL of solution. 2. Calculate the Ksp for AlCl3 if 100.0g is required to saturate 150.0 mL of a solution. 3. The solubility of SrF2 is 2.83 x 10-5 M. Calculate the Ksp. 4. The solubility of GaBr3 is 15.8 g per 100.0 mL. Calculate the Ksp. 5. The solubility of Ag2SO4 is 1.33 x 10-7g per 100.0 mL. Calculate the Ksp. 6. If 2.9 x 10-3 g of Ca(OH)2 is needed to saturate 250.0 mL of solution, what is the Ksp? 7. At a certain temperature, a 40.00 mL sample of a saturated solution of barium hydroxide, is neutralized by 29.10 mL of 0.300 M HCl. Calculate the Ksp of Ba(OH)2. Calculate the concentrations of all ions in each solution. 8. 0.50 M Al2(SO4)3(aq) 9. 25.7 g (NH4)3PO4(aq) in 250.0mL H2O. 10. 210. g CoCl2 • 6H2O in 800.0 mL H2O. Worksheet # 5 Ksp to Solubility Calculate the solubility in M and g/L for each. Use the Ksp values found in your chart. 1. BaCO3 2. Fe(OH)2 3. PbCl2 4. How many grams of Mg(OH)2 are required to completely saturate 1.5 L of solution? Review 1. If 200.0 g of MgCl2 is required to saturate 1.5 L of solution at 20 oC, calculate the Ksp. 2. If the Ksp for Al2O3 is 2.8 x 10-8, calculate [Al3+] and [O-2] in Worksheet # 6 mol /L. Trial Ksp 1. Will a precipitate form if 200.0 mL 0.00020M Ca(NO3)2 is mixed 300.0 mL of 0.00030M Na2C03? 2. Will a precipitate form if 25.0 mL of .0020M Pb(NO3)2 is mixed with 25.0 mL of 0.040M NaBr. 3. Will a precipitate form if equal volumes of 0.00020M Ca(NO3)2 is mixed with 0.00030M Na2C03? 4. Co(OH)2 5. Ag2C2O4 Solubility = 8.3 x 10-4 M Solubility = 3.0 x 10-3 g/L Calculate the Ksp at 250 C. Ksp=? 6. SrF2 Calculate the solubility in (M). 7. Cu(IO3)2 Worksheet # 7 chart!! 1. 2. 3. 4. 5. Solubility Calculate the solubility in (g/L). Separation Positive Ions: Work from top to bottom of solubility Ag+ Mg2+ Ba2+ i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: Pb2+ Ba2+ i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: Cu+ Ca2+ i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: Be2+ Sr2+ i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: Be2+ Ca2+ i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: Sr2+ Sr2+ Ag+ Pb2+ 6. Calculate the Ksp for CaCl2, if 50.0 g is required to saturate 25.0 mL of water. 7. Calculate the molar solubility of Mg(OH)2. 8. Will a precipitate form if equal volumes of 0.00020 M Na2CO3 is mixed with 0.00020 M MgCl2. 9. Write the formula, complete, and net ionic equation. Formula Equation: Complete Ionic: CaCl2(aq) + AgNO3(aq) → Net Ionic: Separation of Negative Ions: Work from bottom to top of solubility chart!! 1. 2. 3. 4. 5. 6. SO32- OH- I- i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: CO32- OHi) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: Br- S2- i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: PO43- OH- PO43- S2- i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: OH- S2- i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: S2- SO42- Cl- i) Add: Filter Out: Net Ionic equation: ii) Add: Filter Out: Net Ionic equation: iii) Add: Filter Out: Net Ionic equation: SO42- Common Ion Effect Worksheet # 8 Consider the following equilibrium system. PbCl2(s) ⇄ Pb2+(aq) + 2 Cl-(aq) Describe what happens to the solubility of PbCl2 after each of the changes. 1. 2. 3. 4. 5. PbCl2(s) is added Pb(NO3)2 is added NaCl is added H2O is added AgNO3 is added 6. NaBr is added Consider the following equilibrium system. AgBr(s) ⇄ Ag+(aq) + Br-(aq) Describe what happens to the solubility of AgBr after each of the changes are made. 7. AgBr(s) is added 8. Pb(NO3)2 is added 9. NaCl is added 10. H2O is added 11. AgNO3 is added 12. NaBr is added 13. Explain why more Zn(OH)2 dissolves when 3 M HCl is added to a saturated solution of Zn(OH)2. Start by writing the correct equilibrium equation. 14. In an experiment, 0.1 M AgNO3 is added to 0.1 M NaCl, resulting in the formation of a white precipitate. When 0.1 M NaI is added to this mixture, the white precipitate dissolves and a yellow precipitate forms. The formula for the white precipitate is The formula for the yellow precipitate is The net ionic equation for the first equilibrium is The net ionic equation for the formation of the yellow precipitate is Explain why the white precipitate dissolves. Start by writing the equilibrium equation for the white precipitate, then, explain how adding NaI affects this equilibrium. Titrations and Maximum Ion Concentration 1. Worksheet # 9 In a titration 25.0 ml of a 0.250 M AgNO3 solution was used to precipitate out all of the Br- in a 200.0 ml sample. Calculate [Br-]. In a titration 26.5ml of 0.100M Pb(NO3)2 was used to precipitate out all of the Clin a 30.0 ml sample of water. Calculate [Cl-]. Maximum Ion Concentration 2. 3. Calculate the maximum concentration of OH- that can exist in a 0.200M Mg(N03)2 solution. 4. Calculate the maximum concentration of CO3-2 that can exist in a 0.500M AgNO3 solution. 5. Calculate the maximum concentration of IO3- that can exist in a 0.200M Cu(N03)2 solution. 6. Calculate the maximum concentration of Ca2+ that can exist in a 0.200 M Na2C03 solution. 7. Calculate the minimum number of moles of Pb(NO3)2 required to start precipitation in 50.0 mL of 0.15 M ZnCl2. 8. In a titration 12.5 mL of 2.00 x 10-5 M HCl is required to neutralize 250.0 mL of saturated AgOH solution. Calculate the [OH-] and then determine the Ksp for AgOH. 9. When excess Ag2CO3(s) is shaken with 1.00 L of 0.200 M K2CO3 it is determined that 6.00 x 10-6 moles of Ag2CO3 dissolves. Calculate the solubility product of Ag2CO3. Quiz #1 1. To determine the solubility of solute in water, a solution must be prepared that is: A. B. C. D. 2. 4. zero one two three Which one of the following equilibrium systems is described by Ksp? A. CaCO3(s) ⇄ CaO(s) + CO2(g) B. CaCO3(s) ⇄ Ca2+(aq) + CO32- (aq) C. Ca 2+(aq) + CO2-3(aq) ⇄ CaCO3(s) D. Ca(OH)2(aq) + H2CO3(aq) ⇄ CaCO3(s) + 2H2O(l) In a saturated solution, the rate of dissolving is A. B. C. D. 5. saturated unsaturated concentrated supersaturated From the list of salts below, how many are considered soluble at 25oC? CuCl2 CaSO4 PbS Ag3PO4 A. B. C. D. 3. Solubility and Saturated Solutions equal to zero equal to the rate of crystallization less than the rate of crystallization greater than the rate of crystallization A soluble magnesium salt is A. B. C. D. 6. 7. The equation that represents the equilibrium in a saturated solution of Fe2(SO4)3 is A. Fe2(SO4)3(s) ⇄ 3Fe2+(aq) + 2SO43-(aq) B. Fe2(SO4)3(s) ⇄ 2Fe2+(aq) + 3SO43-(aq) C. Fe2(SO4)3(s) ⇄ 3Fe3+(aq) + 2SO42-(aq) D. Fe2(SO4)3(s) ⇄ 2Fe3+(aq) + 3SO42-(aq) Which one of the following salts is soluble? A. B. C. D. 8. 9. BaSO4 CaCO3 K3PO4 Fe(OH)2 The equation representing the equilibrium in a saturated solution of CaSO4 is A. CaSO4(s) ⇄ Ca2+(aq) + SO42-(aq) B. CaSO4(s) ⇄ Ca2+(aq) + S2-(aq) + 4O2-(aq) C. CaSO4(s) + H2O(l) ⇄ CaO(aq) + H2SO4(aq) D. CaSO4(s) + 2H2O(l) ⇄ Ca(OH)2(aq) + H2SO4(aq) Which of the following units is commonly used to describe solubility? A. B. C. D. 10. MgSO3 MgCO3 Mg(NO3)2 Mg3(PO4)2 mL/s g/oC mol/L o C/mol Which of the following represents the equilibrium in a saturated solution of Cr2(SO4)3 A. Cr2(SO4)3(s) ⇄ Cr2+(aq) + SO43-(aq) B. Cr2(SO4)3(s) ⇄ Cr3+(aq) + SO42-(aq) C. Cr2(SO4)3(s) ⇄ 2Cr2+(aq) + 3SO43-(aq) D. Cr2(SO4)3(s) ⇄ 2Cr3+(aq) + 3SO42-(aq) Quiz #2 1. A 200.0 mL solution contains 0.050 mol of Ba(NO3)2. The [NO3-] is A. B. C. D. 2. 5. Ksp = [Ca2+][PO43-] Ksp = [Ca2+]3[PO43-]2 Ksp = [3Ca2+][2PO43-] Ksp = [3Ca2+]3[2PO43-]2 In 1.5 M (NH4)2SO4 , the ion concentrations are A. B. C. D. 4. 0.050 M 0.10 M 0.25 M 0.50 M The Ksp expression for a saturated solution of Ca3(PO4)2 is A. B. C. D. 3. Ionic Concentrations Calculations & Ionic Equations [NH4+] = 1.5 M and [SO42-] = 1.5 M [NH4+] = 1.5 M and [SO42-] = 3.0 M [NH4+] = 3.0 M and [SO42-] = 1.5 M [NH4+] = 3.0 M and [SO42-] = 3.0 M The Ksp expression for Ca3(PO4)2 is A. Ksp = [Ca2+]3[PO43-]2 [Ca3(PO4)2] B. Ksp = [2Ca2+][3PO43-] [Ca3(PO4)2] C. Ksp = [Ca2+]3[PO43-]2 D. Ksp = [2Ca2+][3PO43-] The solubility product expression for a saturated solution of Fe2(SO4)3 is A. Ksp = [Fe3+]2[SO42-]3 B. Ksp = [2Fe3+][3SO42-] 6. C. Ksp = [Fe3+]2[SO42-]3 [Fe2(SO4)3] D. Ksp = [2Fe3+][3SO42-] [Fe2(SO4)3] Molecular solutions do not conduct electricity because they contain A. B. C. D. 7. If equal volumes of 0.2 M KBr and 0.2M FeSO4 are mixed, then A. B. C. D. 8. A precipitate does not form A precipitate of ZnS forms A precipitate of MgSO4 forms Precipitates of MgSO4 and ZnS form In an experiment, 0.500 mol of Fe(NO3)3 is dissolved in water to produce a 2.00 L solution. The [NO3-] in this solution is A. B. C. D. 10. No precipitate will be observed A precipitate of FeBr2 will be observed A precipitate of K2SO4 will be observed A precipitate of both K2SO4 and FeBr2 will be observed Which of the following occurs when equal volumes of 0.20 M MgS and 0.20 M ZnSO4 are mixed? A. B. C. D. 9. Molecules only Cations and anions Molecules and anions Molecules and cations 0.250 M 0.500 M 0.750 M 1.50 M The complete ionic equation for the reaction between MgCl2(aq) and AgNO3(Aq) is A. B. C. D. Ag+(aq) + Cl-(aq) → AgCl(s) 2AgNO3(aq) + MgCl2(aq) → 2AgCl(s) + Mg(NO3)2(aq) 2Ag+(aq) + Mg2+(aq) + 2NO3- (aq) + 2Cl-(aq) → MgCl2(s) + 2Ag+(aq) + 2NO3- (aq) 2Ag+(aq) + 2NO3- (aq) + Mg2+(aq) + 2Cl-(aq) → 2AgCl(s) + Mg2+(aq)+ 2NO3- (aq) 11. Which one of the following would form an ionic solution when dissolved in water? A. B. C. D. 12. If the solubility of Pb (OH) 2 is 0.155g/L, then the concentration of each ion in a saturated solution of a Pb (OH) 2 is A. B. C. D. 13. 14. [Pb2+] = 0.155 g/L and [OH-] = 0.155g/L [Pb2+] = 0.052 g/L and [OH-] = 0.103g/L [Pb2+] = 6.43 x 10-4 M and [OH-] = 1.29 x 10-3 M [Pb2+] = 6.43 x 10-4 M and [OH-] = 6.43 x 10-4 M The Ksp expression for calcium hydroxide is A. Ksp = [Ca2+][OH-]2 B. Ksp = C. Ksp = [Ca2+][2OH-]2 D. Ksp = 1 [Ca2+][OH-]2 1 [Ca2+][2OH-]2 A precipitation reaction occurs when equal volumes of 0.2 M Pb(NO3)2 and 0.2 M KI are mixed. The net ionic equation for this reaction is A. B. C. D. 15. I2 CH3OH Ca(NO3)2 Cl2H22O11 Pb2+(aq) + 2I-(aq) → PbI2(s) PbI2(s) → Pb2+(aq) + 2I-(aq) K+(aq) + NO3-(aq) → KNO3(s) KNO3(s) → K+(aq) + NO3-(aq) When dissolved in water, which of the following is an ionic solution? A. B. C. O2 CH4 CaCl2 D. 16. In a 200.0 mL sample of 0.030 M Na3PO4, the [Na+] is A. B. C. D. Quiz #3 1. Solubility to Ksp 9.1 x 10-14 3.6 x 10-13 2.0 x 10-9 4.1 x 10-9 The solubility of manganese (II) sulphide is 1.7 x 10-7 M at 25oC. The solubility product constant is A. B. C. D. 3. 0.006 M 0.010 M 0.018 M 0.090 M In a saturated solution of manganese (II) hydroxide, Mn(OH)2, and [Mn2+] equals 4.5 x 10-5 M. therefore, the Ksp of Mn(OH)2 is A. B. C. D. 2. C12H22O11 2.9 x 10-14 1.7 x 10-7 3.4 x 10-7 4.1 x 10-4 The compound Ag2S has a solubility of 1.3 x 10-4 moles per litre at 25oC. The Ksp for this compound is A. B. C. D. 2.2 x 10-12 8.8 x 10-12 1.7 x 10-8 3.4 x 10-8 4. The solubility of barium oxalate, BaC2O4, is 4.8 x 10-4 M. The value of Ksp is 5. A. 2.3 x 10-7 B. 4.8 x 10-4 C. 2.4 x 10-4 D. 2.2 x 10-2 The solubility of MnS is 4.8 x 10-7 M, at 25oC. The Ksp value is A. B. C. 2.3 x 10-13 4.8 x 10-7 9.6 x 10-7 D. 6. At 25oC, the solubility of an unknown compound is 7.1 x 10-5 M. the compound is A. B. C. D. 7. CuI AgI CaCO3 CaSO4 The solubility of barium fluoride is 3.6 x 10-3 M. the solubility product constant is A. B. C. D. 8. 6.9 x 10-4 4.7 x 10-8 1.9 x 10-7 1.3 x 10-5 2.6 x 10-5 At a certain temperature, the solubility of BaF2 is 7.4 x 10-3 moles per litre. The Ksp of BaF2 is A. B. C. D. 1.6 x 10-6 5.5 x 10-5 1.1 x 10-4 7.4 x 10-3 Quiz #4 1. Identify the most soluble sulphide A. B. C. D. 2. HgS, PbS, FeS, MnS, Ksp = 1.6 x 10-54 Ksp = 7.0 x 10-29 Ksp = 3.7 x 10-19 Ksp = 2.3 x 10-13 Saturated solutions of Na2S, CuS, SnS2, and Al2S3 are prepared at 25oC. The [S2-] will be greatest in the solution of A. B. C. D. 3. Ksp to Solubility and Size of Ksp Na2S CuS SnS2 Al2S3 A solution of AgNO3 is slowly added to a mixture containing 0.10 M I-, Cl-, Br-, and IO3-. The precipitate, which forms first, is A. AgI B. C. D. 4. The [OH-] is measured to be 3.3 x 10-3 mol/L in a 100.0 mL sample of saturated solution of Al(OH)3. The solubility of Al(OH)3 is A. B. C. D. 5. 2.8 x 10-9 M 5.3 x 10-5 M 1.1 x 10-4 M 7.3 x 10-3 M At 25oC, the solubility of Mg (OH)2 is A. B. C. D. 9. BaS AlCl3 CaSO3 ZnSO4 The solubility of AgBrO3 is A. B. C. D. 8. 1.2 x 10-16 M 5.5 x 10-9 M 1.1 x 10-8 M 1.0 x 10-4 M The least soluble in salt water is A. B. C. D. 7. 1.1 x 10-4 mol/L 3.3 x 10-4 mol/L 1.1 x 10-3 mol/L 3.3 x 10-3 mol/L The [SO24-] in a saturated solution of PbSO4 is (Ksp = 1.1 x 10-8) A. B. C. D. 6. AgCl AgBr AgIO3 1.1 x 10-32 M 5.6 x 10-12 M 2.4 x 10-6 M 1.1 x 10-4 M A student evaporated 200.0 mL of a saturated solution of SrCrO4 to dryness. The residue contained 1.2 x 10-3 mol SrCrO4. The solubility of SrCrO4 is A. B. 1.4 x 10-6 M 3.6 x 10-5 M C. D. 10. The solubility of magnesium carbonate is A. B. C. D. 11. CaCO3 BaSO4 CuSO4 MgSO4 Which of the following salts has the lowest solubility? A. B. C. D. Quiz #5 1. 9.3 x 10-5 M 3.7 x 10-4 M 4.4 x 10-2 M 1.4 x 10-7 M Which of the following is the least soluble in water at 25oC ? A. B. C. D. 13. 9.3 x 10-5 M 3.4 x 10-6 M 6.8 x 10-6 M 2.6 x 10-3 M A saturated container of NiCO3 was evaporated to dryness. A 250.0 mL sample was found to contain 1.1 x 10-2 g NiCO3. The molecular mass of NiCO3 is 118.7 g/mol. The molar solubility of NiCO3 is A. B. C. D. 12. 2.4 x 10-4 M 6.0 x 10-3 M Copper (I) chloride Ammonium sulphide Potassium hydroxide Mercury (II) sulphate Trial Ksp In an experiment, a student mixes equal volumes of 0.0020 M Pb2+ ions with 0.0040 M I- ions. The trial ion product is A. B. C. D. 2. In an experiment, 20.0 ml of 0.0060 M CaCl2 and 20.0 mL of 0.0050 M NaSO4 are mixed together. The trial ion product (trial Ksp) is A. B. C. D. 3. No precipitate forms A precipitate of only SrS forms A precipitate of only NaOH forms Precipitates of both NaOH and SrS form When solutions of Pb(NO3)2 and NaCl are mixed, the trial ion product (Trial Ksp) is 9.8 x 10-6. Which of the following statements is true? A. B. C. D. 7. AlCl3 precipitates CaSO4 precipitates AlCl3 and CaSO4 precipitate no precipitate forms When a student mixes equal volumes of 0.20 M Na2S and 0.20 M Sr(OH)2. A. B. C. D. 6. Less than 0.10 M More than 10.0 M More than 0.10 M but less than 1.0 M More than 1.0M but less than 10.0 M When 0.20 M Al2(SO4)3 is added to an equal volume of 0.20 M CaCl2, A. B. C. D. 5. 7.5 x 10-6 and a precipitate will form 7.5 x 10-6 and a precipitate will not form 3.0 x 10-5 and a precipitate will form 3.0 x 10-5 and a precipitate will not form In a saturated solution of Zn(OH)2, the [Zn2+] is A. B. C. D. 4. 4.0 x 10-9 3.2 x 10-8 1.3 x 10-7 8.0 x 10-6 A precipitate forms because Ksp > 9.8 x 10-6 A precipitate forms because Ksp < 9.8 x 10-6 A precipitate does not form because Ksp < 9.8 x 10-6 A precipitate does not form because Ksp > 9.8 x 10-6 When equal volumes of 0.060 M AgNO3 and 0.00090 M NaBrO3 are mixed, the trial ion product (TIP) is A. Less than Ksp and a precipitate forms B. C. D. 8. The mixture that could produce a precipitate of two compounds is A. B. C. D. 9. SrS SrCl2 SrSO4 Sr(OH)2 When equal volumes of 2.0 M Pb(NO3)2 and 2.0 M KCl are mixed A. B. C. D. Quiz #6 1. 0.2 M HgSO4 and 0.2 M FeCl2 0.2 M AgNO3 and 0.2 MgCl2 0.2 M K2CO3 and 0.2 CuSO4 0.2 M ZnSO4 and 0.2 Ba(OH)2 Which of the following has a solubility of less than 0.10 M? A. B. C. D. 10. Greater than Ksp and a precipitate forms Less than Ksp and no precipitate forms Greater than Ksp and no precipitate forms A precipitate forms because trial ion product < Ksp A precipitate forms because trial ion product > Ksp A precipitate does not form because trial ion product < Ksp A precipitate does not form because trial ion product > Ksp Separating Ions During a lab on qualitative analysis, an unknown solution containing one cation was analyzed and the following data were collected: 0.2 M Anions Added to the Unknown Solution S2SO42OHCO32- Observation no precipitate precipitate precipitate precipitate Which one of the following cations is found in the unknown solution? A. B. C. D. 2. Which of the following could be used to precipitate both Mg2+ and Ca2+ from hard water? A. B. C. D. 3. KNO3 AgNO3 Pb(NO3)2 Al(NO3)3 The precipitate formed when equal volumes of 0.2 M Sr(OH)2 and 0.2 M MgS are mixed is A. B. C. D. 5. Lithium sulphate Sodium phosphate Potassium sulphide Ammonium chloride A reagent that may be used to separate Cl- from S2- by precipitation is A. B. C. D. 4. Mg2+ Be2+ Sr2+ Ba2+ SrS Mg(OH)2 a mixture of Mg(OH)2 and SrS a mixture of Sr(OH)2 and MgS Which of the following ions could be used to separate Cl-(aq) from SO42-(aq) by precipitation? A. B. Ag+ Ca2+ C. D. 6. Which of the following ions could be added to an aqueous mixture containing Pb2+ and Ba2+ to separate the ions by precipitating one of them? A. B. C. D. 7. INO3PO43SO42- Which of the following would precipitate the Ca2+ and Mg2+ found in hard water? A. B. C. D. 8. NH4+ Pb2+ S2PO43SO42CH3COO- A solution containing an unknown cation was added to three solutions and the f following observations were recorded: SOLUTION NaI Na2SO4 NaOH OBSERVATION no precipitate precipitate no precipitate The unknown cation is A. B. C. D. 9. To remove Mg2+ from a solution by precipitation, a student should add A. B. C. D. 10. Pb2+ Sr2+ Ca2+ Ag+ NaI KOH Li2SO4 (NH4)2S Which of the following could be used to separate Pb2+ from Ba2+ by precipitation? A. B. C. Na2S NaOH Na2CO3 D. 11. A student wishes to identify an unknown cation in a solution. A precipitate does not form with the addition of SO42-, but does form with the addition of S2-. Which of the following is the unknown cation? A. B. C. D. 12. Ag+ Mg2+ Ca2+ Cu2+ A solution contains CO32- and OH-. Separation of these two anions by selective precipitation is accomplished by first adding Sr(NO3)2 solution, then filtering and finally adding to the filtrate a solution of A. B. C. D. 13. Na3PO4 HNO3 RbNO3 NH4NO3 Zn(NO3)2 A nitrate solution containing an unknown cation is added to each of the following three test tubes. 1.0 M NaOH 1.0 M Na2S 1.0 M Na2SO4 A precipitate forms in one test tube only. The unknown cation is A. B. C. D. Ag+ Ca2+ Sr2+ NH4+ 14. A solution containing a single unknown cation is added to three test tubes. the following anions were added and observations were recorded. TEST TUBE 1 2 3 ANION ADDED SO42S2OH- OBSERVATION precipitate precipitate precipitate The solution contains A. B. C. D. Sr2+ Ag+ or Pb2+ Ca2+ or Ba2+ K+, NH4+ or H+ Quiz #7 1. Common Ion Effect Consider the following equilibrium: CaCO3(s) ⇄ Ca2+(aq) + CO32-(aq) Which of the following reagents, when added to the equilibrium system, would cause more CaCO3 to dissolve? A. B. C. D. 2. A solution contains a mixture of SO42- and S2-. Which of the following cations could be used to remove only the SO42- from the solution by precipitation? A. B. C. D. 3. KNO3(s) CaCO3(s) H2C2O4(s) Na2CO3(s) K+ Sr2+ Pb2+ Cu2+ Consider the following solubility equilibrium: MgCO3(s)⇄ Mg2+(aq) + CO32-(aq) The addition of which of the following substances would decrease the solubility of MgCO3? A. B. C. H2O NaCl NaOH 4. D. Na2CO3 A student could precipitate silver chloride from a saturated solution of silver chloride by adding A. B. C. D. 5. The greatest mass of solid SnS will dissolve in 1.0 L of A. B. C. D. 6. [I-] increases and [Pb2+] increases [I-] decreases and [Pb2+] decreases [I-] increases and [Pb2+] decreases [I-] decreases and [Pb2+] increases Consider the following equilibrium: Pbl2(s) + heat ⇄ Pb2+(aq) + 2I-(aq) Which of the following changes would result in more Pbl2 dissolving? A. B. C. D. 9. MgCl2 NaNO3 Na2CO3 Mg(NO3)2 Sodium iodide is added to a saturated solution of lead (II) iodide. The net change is A. B. C. D. 8. H2O 0.10 M MgS 0.10 M (NH4)2S 0.10 M Sn(NO3)2 Magnesium carbonate would be the most soluble in a solution of A. B. C. D. 7. Water Sodium iodide Sodium nitrate Sodium chloride Adding more Pbl2 Increasing the pressure Adding some Pb(NO3)2 Increasing the temperature Consider the following equilibrium: AgCl(s) ⇄ Ag+(aq) + Cl-(aq) Sodium chloride is added to a saturated solution of AgCl. The amount of solid AgCl will A. B. Increase as the equilibrium shifts to the left Decrease as the equilibrium shifts to the left C. D. 10. Consider the following equilibrium: NH4Cl(s) + energy ⇄ NH+4(aq) + Cl-(aq) Which of the following will increase the solubility of ammonium chloride? A. B. C. D. Quiz #8 1. 1.1 x 10-5 M 5.3 x 10-5 M 2.6 x 10-4 M 7.3 x 10-3 M 3.4 x 10-7M 3.4 x 10-6 M 1.7 x 10-6 M 5.8 x 10-4 M A student titrates a 25.00 mL sample of well water with 18.2 mL 0.100 M AgNO3 to completely precipitate the chloride ion. The [Cl-] is A. B. C. D. 4. Titrations and Max Ion Concentration What is the maximum [Sr2+] that can exist in a solution of 0.10 M Na2SO4? A. B. C. D. 3. Stirring the solution Adding more water Adding more NH4Cl(s) Increasing the temperature What is the maximum [Ag+] that can exist in 0.20 M NaBrO3? A. B. C. D. 2. Increase as the equilibrium shifts to the right Decrease as the equilibrium shifts to the right 1.82 x 10-3 M 7.28 x 10-2 M 1.37 x 10-1 M 1.50 x 10-1 M What is the maximum concentration of sodium sulphate, Na2SO4, that will dissolve in 1.0 L of 0.10 M Pb(NO3)2 without forming a precipitate? A. B. C. D. 1.8 x 10-8 M 1.8 x 10-7 M 1.3 x 10-4 M 1.0 x 10-1 M 5. Consider the following equilibrium: AgCl(s) ⇄ Ag+(aq) + Cl-(aq) When Br-(aq) is added to a saturated solution of AgCl, A. B. C. D. 6. In a saturated solution of zinc hydroxide, at 40oC, the [Zn2+] = 1.8 x 10-5 M. The Ksp of Zn(OH)2 is A. B. C. D. 7. 1 M HCl 1 M MgCl2 1 M AgNO3 1 M NH4NO3 At 25oC, the maximum [Zn2+] that can exist in a 0.250 M Na2S is A. B. C. D. 10. [Co2+] = 3.5 M and [Cl-] = 3.5 M [Co2+] = 3.5 M and [Cl-] = 7.0 M [Co2+] = 0.35 M and [Cl-] = 0.35 M [Co2+] = 0.35 M and [Cl-] = 0.70 M In which of the following would solid AgCl be most soluble? A. B. C. D. 9. 5.8 x 10-15 2.3 x 10-14 1.8 x 10-14 6.5 x 10-10 What is the [Co2+] and [Cl-] when 0.35 mol of CoCl2 is dissolved in enough water to make 100.0 mL of solution? A. B. C. D. 8. More AgCl dissolves and its solubility product increases More AgCl precipitates and its solubility product decreases More AgCl dissolves and its solubility product remains constant More AgCl precipitates and its solubility product remains constant 5.0 x 10-26 2.0 x 10-25 8.0 x 10-25 4.5 x 10-13 The molar solubility of iron (II) sulphide is A. B. C. D. 3.6 x 10-37 3.0 x 10-19 6.0 x 10-19 7.7 x 10-10 Solubility Web Review 1. Describe the relationship between the rate of dissolving solid and rate of crystallization: a) A saturated solution and some solid b) An unsaturated solution and some solid c) A supersaturated solution and some solid is added 2. Write the equilibrium expression and Ksp equation for Fe2O3. 3. Write the net ionic equation for the reaction between Al(NO3)3 and Na2CO3. Note the difference between this equation and the last one. 4. Mg+2, Sr+2, Ca+2 and Be+2 are possibly in a solution. The solution reacts with Na2SO4 but not NaOH or Na2S. What cations are in the solution? 5. A solution contains SO42- or OH- or both. It reacts with Zn(NO3)2and Sr(NO3)2, What anions are in the solution? 6. Ag2CO3(s) ⇄ 2Ag+ + CO32- Describe the effect on the solubility of Ag2CO3 for each change below: a) Add Ag2CO3 b) Add water c) Add NaCl d) Add Pb(NO3)2 e) Add Na2CO3 f) Add AgNO3. 7. If the trial Ksp = 1.7x10-7 and the Ksp = 3.8x10-7 will a precipitate occur? 8. For a saturated solution of Fe(OH)3 the [OH-] is found to be 1.3x10-4 M. Calculate the [Fe+3] and the solubility of the salt in moles/L. 9. Consider the equilibrium that exists in a saturated solution of PbCl2. Write the equilibrium expression. If the equilibrium shifts to the right, what affect does this have on the solubility? Describe how the addition of each of the following will affect the solubility of PbCl2. a) AgNO3 b) NaCl c) Na2S d) H2O 10. e) NaNO3 f) Pb(NO3)2 If the reaction is endothermic, how do the Ksp and the solubility change if the temperature is increased? What is the only way to change the Ksp? Calculations 1. In a titration 250 mL of a .200 M AgNO3 solution was used to precipitate out all of the Cl- in a 500 mL sample. Calculate [Cl-]. 2. In a titration 26.5 mL of .100M Pb(NO3)2 was used to precipitate out all of the Iin a 3.00 mL sample of water. Calculate [I-]. 3. Co(OH)2 Solubility = 3.0x10-3 g/L Ksp=? 4. Ag2C2O4 Solubility = 8.3x10-4 M Ksp=? 5. SrF2 Ksp = 2.8 x 10-9 Solubility in (M) = ? Ksp = 1.4 x 10-7 6. Cu(IO3)2 Solubility (g/L) = ? 7. Calculate the maximum concentration of OH- that can exist in a 0.200M Ca(N03)2 solution. Ksp (Ca(OH)2) = 2.8 x 10-8 8. Calculate the maximum concentration of CO3-2 that can exist in a 0.500 M Fe(NO3)3 solution. Ksp (Fe2(CO3)3) = 2.8 x 10-14 9. Will a precipitate form if 200.0 mL .0020M Mg(NO3)2 is mixed 300.0 mL of 0.0030M NaOH? 10. Will a precipitate form if 25.0mL of .0020M Pb(NO3)2 is mixed with 25.0mL of 0.040M NaBr. 11. 20.0 g of PbCl2 is placed in 2.0 L of water. Some but not all dissolves to form a saturated solution. How many grams do not dissolve? Solubility Practice Test # 1 1. Which combination of factors will affect the rate of the following reaction? Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g) A. B. C. D. 2. Temperature and surface area only Temperature and concentration only Concentration and surface area only Temperature, concentration, and surface area Consider the following reaction: 2MnO4-(aq) + 5C2O42- + 16H+(aq) → 2Mn2+(aq) + 10CO2(g) + 8H2O(l) The rate of decomposition of the oxalate ion is increased by A. B. C. D. Adding NaOH Removing CO2 Adding a catalyst Decreasing the pressure 3. An equilibrium system shifts left when the temperature is increased. The forward rate is A. Exothermic and ∆H is positive. B. Exothermic and ∆H is negative. C. Endothermic and ∆H is positive. D. Endothermic and ∆H is negative. 4. The value of the Keq can be changed by A. B. C. D. 5. adding a catalyst. changing the temperature. changing the reactant concentration. changing the volume of the container Consider the following equilibrium: 2NOCl(g) ⇄ 2NO(g) + Cl2(g) In a 1.0 L container at equilibrium there are 1.0 mol NOCl, 0.70 mol NO and 0.40 mol Cl2. At constant temperature and volume, 0.10 mol NOCl is added. The concentrations in the “new” equilibrium in comparison to the concentrations in the “old” equilibrium are [NOCl] [NO] [Cl2] A B C D 6. 7. A. Fe2(SO4)3(s) ⇄ 3Fe2+(aq) + 2SO43-(aq) B. Fe2(SO4)3(s) ⇄ 2Fe2+(aq) + 3SO43-(aq) C. Fe2(SO4)3(s) ⇄ 3Fe3+(aq) + 2SO42-(aq) D. Fe2(SO4)3(s) ⇄ 2Fe3+(aq) + 3SO42-(aq) KOH Fe(OH)3 Mg(OH)2 Zn(OH)2 When 250 mL of 0.36 M Sr(OH)2 are added to 750 mL of water, the resulting ion concentrations are [Sr2+] [Sr2+] [Sr2+] [Sr2+] = 0.12 M and [OH-] = 0.12 M and [OH-] = 0.090 M and [OH-] = 0.090 M and [OH-] = = = = 0.12 M 0.24 M 0.090 M 0.180 M When equal volumes of 2.0 M Pb(NO3)2 and 2.0 M KCl are mixed, A. B. C. D. 11. K+(aq) + NO3-(aq) → KNO3(s) 2Ag+(aq) + CrO42-(aq) → Ag2CrO4(s) K2CrO4(aq) + 2AgNO3(aq) → Ag2CrO4(s) + 2KNO3(aq) 2Ag+(aq) + CrO4-(aq) + 2K+(aq) + 2NO3-(aq) → Ag2CrO4(s) + 2KNO3(s) Which of the following compounds could be used to prepare a 0.20 M solution of hydroxide ion? A. B. C. D. 10. new = old new > old new > old new > old When equal volumes of 0.20 M K2CrO4 and 0.20 M AgNO3 are mixed, a red precipitate is formed. The net ionic equation for this reaction is A. B. C. D. 9. new = old new > old new < old new > old The equation that represents the equilibrium in a saturated solution of Fe2(SO4)3 is A. B. C. D. 8. new = old new > old new < old new < old a precipitate forms because the trial ion product < Ksp a precipitate forms because the trial ion product > Ksp a precipitate does not form because the trial ion product < Ksp a precipitate does not form because the trial ion product > Ksp Consider the following equilibrium: AgCl(s) ⇄ Ag+(aq) + Cl-(aq) When Br-(aq) is added to a saturated solution of AgCl, A. B. C. D. more AgCl dissolves and its solubility product increases. more AgCl precipitates and its solubility product decreases. more AgCl dissolves and its solubility product remains constant. more AgCl precipitates and its solubility product remains constant. 12. The molar solubility of iron II sulphide is A. B. C. D. 13. 3.6 3.0 6.0 7.7 x x x x 10-37 M 10-19 M 10-19 M 10-10 M A solution containing an unknown cation was added to three solutions and the following observations were recorded: Solution NaI Observation no precipitate The unknown cation is A. B. C. D. 14. [Pb2+] [Pb2+] [Pb2+] [Pb2+] = = = = 0.155 g/L and [OH-] = 0.155 g/L 0.155 g/L and [OH-] = 0.103 g/L 6.43 x 10-4 M and [OH-] = 1.29 x 10-3 M 6.43 x 10-4 M and [OH-] = 6.43 x 10-3 M Na2S NaOH Na2CO3 Na2SO4 When dissolved in water, which of the following form a molecular solution? A. B. C. D. 17. Pb2+ Sr2+ Ca2+ Ag+ Which of the following could be used to separate Pb2+ from Ba2+ by precipitation? A. B. C. D. 16. NaOH no precipitate If the solubility of Pb(OH)2 is 0.155 g/L, then the concentration of each ion in a saturated solution is A. B. C. D. 15. Na2SO4 precipitate HCl(g) NaNO3(s) CH3OH(l) K2SO4(s) Which of the following will be most soluble in water at 25 oC. A. AgI B. PbS C. MgSO4 D. Ba(OH)2 18. At 25 oC, the solubility of Mg(OH)2 is A. B. C. D. 19. increasing decreasing increasing no change 8.4 x 10-28 2.9 x 10-14 5.8 x 10-14 1.7 x 10-7 Which of the following causes a precipitate to form when Sr2+(aq) is added but not when Zn2+(aq) is added? A. B. C. D. 23. increasing increasing decreasing increasing The solubility of PbS is 2.9 x 10-14 M. What is the value of the Ksp. A. B. C. D. 22. CuI AgI CaCO3 CaSO4 When solid AgBr is added to a saturated solution of AgBr, the reaction rates can be described as: Rate of Dissolving Rate of Crystalizing A. B. C. D. 21. x 10-32 M x 10-12 M x 10-6 M x 10-4 M At 25 oC, the solubility of an unknown compound is 7.1 x 10-5 M. The compound is A. B. C. D. 20. 1.1 1.1 1.1 1.1 S2ClSO42CO32- A 3.0 L solution of NiCl2 is found to have a chloride concentration of 0.60 M. The concentration of nickel II ions is A. B. C. D. 0.30 M 0.60 M 0.90 M 1.2 M 24. When equal volumes of 0.20 M K2CO3 and 0.2 M Na3PO4 are mixed, A. B. C. D. 25. A solution of AgNO3 is slowly added to a mixture containing 0.10 M I-, Cl-, Br-, and IO3-. The precipitate which forms first is A. B. C. D. 26. no precipitate will form a precipitate of K3PO4 will form a precipitate of Na2CO3 will form a precipitate of K3PO4 and Na2CO3 will form AgI AgCl AgBr AgIO3 Which of the following units can be used to represent solubility? A. B. C. D. g mol mol/L mL/s 27. Consider the following equilibrium: CaCO3(s) ⇄ Ca2+(aq) + CO32-(aq) Which of the following reagents when added to the equilibrium system, would cause more CaCO3 to dissolve? A. KNO3(s) B. CaCO3(s) C. H2C2O4(s) D. Na2CO3(s) 28. Which of the following could be used to precipitate both Mg2+ and Ca2+ from hard water? A. B. C. D. 29. lithium sulphate sodium phosphate potassium sulphide ammonium chloride What is the maximum [Ag+] that can exist in 0.20 M NaBrO3? A. B. C. D. 1.1 x 10-5 M 5.3 x 10-5 M 2.6 x 10-4 M 7.3 x 10-3 M 30. Which of the following ions could be used to separate Cl-(aq) from SO42-(aq) by precipitation? A. B. C. D. 31. The Ksp expression for a saturated solution Ca3(PO4)2 is A. B. C. D. 32. 35. = = = = [Ca2+][PO43-] [Ca2+]3[PO43-]2 [3Ca2+][2PO43-] [3Ca2+][2PO43-] solution will be saturated pH will be less than 7 trial Ksp is less than the Ksp concentrations of the ions are equal Which of the following describes the changes in ion concentrations when 1.0 g of solid ZnS is added to a saturated solution of ZnS? A. B. C. D. 34. Ksp Ksp Ksp Ksp When Ca(OH)2 attains solubility equilibrium, the A. B. C. D. 33. Ag+ Ca2+ NH4+ Pb2+ [Zn2+] [S2-] increases decreases increases remains constant decreases decreases increases remains constant The net ionic equation for the reaction between Sr(OH)2 and H2SO4 is A. B. C. H+ + OH- → H2O Sr2+ + SO42- → SrSO4 Sr(OH)2 + H2SO4 → SrSO4 + 2H2O D. Sr2+ + 2OH- + 2H+ + SO42- → SrSO4 + 2H2O The relationship between the solubility and the size of the Ksp is A. B. C. there is no relationship the smaller the Ksp the greater the solubility the greater the Ksp the greater the solubility 36. D. the solubility is always the square root of the Ksp Which of the following compounds will form a saturated solution with the greatest concentration of Ag+? A. B. C. D. 37. When equal volumes of 0.20 M CuSO4 and 0.20 M Li2S are combined, the complete ionic equation is A. B. C. D. 38. S2-(aq) → CuS(s) + Li2S(aq) → CuS(s) + Li2SO4(aq) SO42-(aq) + 2Li+(aq) + S2-(aq) → CuS(s) + Li2SO4(aq) SO42-(aq) + 2Li+(aq) + S2-(aq) → CuS(s) + 2Li+(aq) + SO42-(aq) 0.40 L of 0.050 M Fe(NO3)3 0.80 L of 0.020 M Fe2(SO4)3 0.50 L of 0.040 M FeC6H5O7 0.50 L of 0.010 M Fe2(C2O4)3 A solution contains both Ag+ and Mg2+ ions. During selective precipitation, these ions are removed one at a time by adding A. B. C. D. 40. Cu2+(aq) + CuSO4(aq) Cu2+(aq) + Cu2+(aq) + Which of the following would have the [Fe3+] = 0.020 M? A. B. C. D. 39. AgI AgBr AgIO3 AgBrO3 I- followed by OHOH- followed by S2SO42- followed by ClNO3- followed by PO43- The solubility of an AB2 type salt is 2.3 x 10-6 M. The salt is A. B. C. D. PbBr2 Fe(OH)2 Cu(IO3)2 Mg(OH)2 1. A saturated solution of BaSO4 is given to patients needing digestive tract x-rays. a) Write an equation that represents the solubility equilibrium b) Calculate the [Ba2+] present in the saturated solution. 2. Will a precipitate form when 90.0 mL of 1.00 x 10-2 M Cu(NO3)2 and 10.0 mL of 1.00 x 10-2 M NaIO3 are mixed? Explain using appropriate calculations. 3. What is the maximum [CO32-] that can exist in a 1.3 x 10-4 M AgNO3 solution? 4. The following data was collected when a 25.00 mL sample of water containing chloride ion was titrated using 0.100 M AgNO3 to completely precipitate the chloride ion. Initial volume of AgNO3 Final volume of AgNO3 18.30 mL 27.22 mL a) Write the net ionic reaction for the precipitation reaction. c) Calculate the [Cl-]. 5. In an experiment to determine the solubility of BaF2, 500.0 mL of the saturated solution was heated in an evaporating dish to remove the water. The evaporating dish and the residue were then heated two more times to ensure all the water was removed. Volume of the saturated solution of BaF2 Mass of the evaporating dish Mass of the evaporating dish and BaF2 after the first heating Mass of the evaporating dish and BaF2 after the second heating Mass of the evaporating dish and BaF2 after the third heating Using the above data, calculate the Ksp for BaF2 500.0 mL 72.540 g 73.500 g 72.855 g 72.855 g Chemistry 12 Solubility Test # 2 1. Consider the following experiment: 1.0 mL 0.20 M Ag+ + an unknown solution → 1.0 mL 020 M Sr2+ + an unknown solution → The unknown solution could contain A B C D 2. 0.062 M 1.60 M 3.65 M 6.24 M Calculate the [Li+] in 200.0 mL of 1.5 M Li2SO4. A B C D 5. CuS AgBr CaCO3 CaSO4 A saturated solution of NaCl contains 36.5 g of solute in 0.100 L of solution. The solubility of the compound is A B C D 4. 0.20 M OH0.20 M NO30.20 M PO430.20 M SO42- A compound has a solubility of 7.1 x 10-5 M at 25 oC. The compound is A B C D 3. precipitate no precipitate 0.30 M 0.60 M 1.5 M 3.0 M The Ksp expression for a saturated solution of Mg(OH)2 is A Ksp = [Mg2+][OH-]2 [Mg(OH)2] B Ksp = [Mg2+][OH-]2 C Ksp = [Mg2+][OH-] D 6. Ksp = [Mg2+][2OH-]2 Consider the following saturated solution solutions CuSO4 BaSO4 CaSO4 The order of cation concentration, from highest to lowest, is A B C D 7. > > > > [Cu2+] [Ba2+] [Ba2+] [Ca2+] 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 7.8 2.8 5.6 1.7 x x x x 10-28 10-14 10-14 10-7 The ion concentrations in 0.25 M Al2(SO4)3 are A B C D 10. [Ca2+] [Cu2+] [Ca2+] [Ba2+] The solubility of CdS = 2.8 x 10-14. The value of the Ksp is A B C D 9. > > > > When 1.0 x 10-3 moles of CuCl2(s) are added to 1.0 L of 1.0 x 10-3 M IO3-, the A B C D 8. [Ba2+] [Ca2+] [Cu2+] [Cu2+] [Al3+] [SO42-] 0.25 M 0.50 M 0.75 M 0.10 M 0.25 M 0.75 M 0.50 M 0.15 M Which of the following will not produce a precipitate when equal volumes of 0.20 M solutions are combined? A B C D KOH and CaCl2 Zn(NO3)2 and K3PO4 Sr(OH)2 and (NH4)2S Na2SO4 and Pb(NO3)2 11. Consider the following equilibrium: Mg(OH)2(s) ⇄ Mg2+(aq) + 2OH-(aq) A compound that can be added to cause a shift to the right is A B C D 12. If the trial ion product for AgBrO3 is calculated to be 1.0 x 10-7, then A B C D 13. 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 Which of the following will dissolve in water to produce a molecular solution? A B C D 14. NaOH HCl Sr(OH)2 Mg(OH)2 CaCl2 NaOH CH3OH Sr(OH)2 In a solubility equilibrium, the A B C D 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 [SO42-] that can exist in 1.0 x 10-3 M Ca(NO3)2 without a precipitate forming is A B C D 16. 7.1 1.0 8.4 7.1 x 10-5 M x 10-3 M x 10-3 M x 10-2 M When equal volumes of 0.20 M CuSO4(aq) and 020 M Li2S(aq) are combined, the complete ionic equation is A Cu2+(aq) + S2-(aq) → CuS(s) B CuSO4(aq) + Li2S(aq) → CuS(s) + Li2SO4(s) C Cu2+(aq) + SO42-(aq) + 2Li+(aq) + S2-(aq) → Li2SO4(aq) CuS(s) D Cu2+(aq) + SO42-(aq) + 2Li(aq) + S2-(aq) → CuS(s) + 2Li+(aq) + + SO42- (aq) 17. Consider the solubility equilibrium: CaCO3(aq) ⇄ Ca2+(aq) + CO32-(aq) An additional piece of solid CaCO3 is added to the equilibrium above. The rate of dissolving and the rate of crystallization have A B C D 18. Rate of crystallization increases increases not changed not changed increases not changed increased not changed At 25 oC, which of the following compounds would dissolve to form a saturated solution with the greatest [Pb2+]? A B C D 19. Rate of Dissolving PbI2 PbCl2 PbBr2 Pb(IO3)2 Consider the following anions: I II III 10.0 mL of 0.20 M Cl10.0 mL of 0.20 M OH10.0 mL of 0.20 M SO32- When 10.0 mL of 0.20 M Pb(NO3)2 are added to each of the above, precipitates form in A B C D 20. I and II only I and III only II and III only I, II, and III Which of the following units could be used to describe solubility? A B C D 21. The solubility of SnS is 3.2 x 10-3 M. The value of the Ksp is A B C D 22. 1.0 M HCl 1.0 M NaNO3 1.0 M ZnCl2 1.0 M AgNO3 4.3 6.6 1.0 1.6 x x x x 10-9 10-5 10-3 10- Ksp Ksp Ksp Ksp = = = = [Ag2+][CO32-] [Ag+]2[CO32-] [2Ag+][CO32-] [2Ag+]2[CO32-] How many moles of solute are dissolved in 200.0 mL of a saturated solution of A B C D 26. 10-5 10-3 10-3 10-2 The Ksp expression for a saturated solution of Ag2CO3 is A B C D 25. FeS? x x x x The solubility of SrF2 is A B C D 24. 1.0 3.2 6.4 5.7 Silver chloride, AgCl, would be least soluble in A B C D 23. g/s g/L M/L mol/s 1.2 6.0 1.5 7.7 x x x x 10-19 10-19 10-10 10-10 A solution contains both Ag+ and Mg2+ ions. During selective precipitation, these ions are removed one at a time by adding A B C D 27. Which of the following does not define solubility? A B C solution D solution 28. [Al3+] [SO42-] 0.25 M 0.50 M 0.75 M 0.10 M 0.25 M 0.75 M 0.50 M 0.15 M KOH and SrCl2 Zn(OH)2 and K3PO4 Zn(OH)2 and (NH4)2S Na2SO4 and Pb(NO3)2 What is observed when H2SO4 is added to a saturated solution of CaSO4? A B C D 31. the minimum amount of solute required to produce one litre of saturated Which of the following will not produce a precipitate when equal volumes of 0.20 M solutions are combined? A B C D 30. 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 The ion concentrations in 0.25 M Al2(SO4)3 are A B C D 29. I- followed by OHOH- followed by S2SO42- followed by ClNO3- followed by PO43- CaSO4(s) dissolves the [Ca2+] increases bubbles of H2 are given off additional CaSO4 precipitates The solubility of CdS is 2.8 x 10-14 M. The value of the Ksp is A B C 7.8 x 10-28 2.8 x 10-14 5.6 x 10-14 D 32. 1.7 x 10-7 Consider the following solutions: 0.10 M Cl0.10 M IO3- 0.10 M Br0.10 M BrO3- Equal moles of AgNO3 are added to each solution. It is observed that a precipitate forms in all but one solution. Which solution does not form a precipitate? A B C D 33. ClBrIO3BrO3- Consider the following equilibrium: 2O3(g) ⇄ 3O2(g) Keq = 65 Initially, 0.10 mole O3 and 0.10 mole of O2 are placed in a 1.0 L container. Which of the following describes the changes in concentrations as the reaction proceeds to equilibrium? A B C D 34. [O3] [O2] decreases decreases increases increases decreases increases decreases increases Consider the following potential energy diagram for the reversible reaction. PE (KJ) 140 130 110 Progress of the reaction A B C D 35. ΔH (kJ) 10 10 30 20 -20 -30 +10 +30 Increasing the temperature of a reaction increases the rate by I increasing frequency of collision II increasing the kinetic energy of collision III decreasing the potential energy of collision A B C D 36. Ea reverse (kJ) I only I and II only II and III only I, II, and III What is the Keq expression for the following equilibrium? Fe (s) + 4H2O(g) ⇄ Fe3O4(s) + 4H2(g) A Keq = [H2]4 B Keq = [H2] [H2O] C Keq = [H2]4 [H2O]4 D Keq = [Fe3O4][H2]4 [Fe]3[H2O]4 Subjective 1. Write the net ionic equation representing the reaction that occurs when 50.0 mL of 0.20 M ZnSO4 and 50.0 mL 0.20 M BaS are combined. 2. A 100.0 mL sample of 0.600M Ca(NO3)2 is diluted by adding 400.0 mL of water. Calculate the concentrations of all of the ions. 3. When 1.00 L of CaF2 was evaporated to dryness, 2.66 x 10-2 g of residue was formed. Calculate the Ksp. 4. A maximum of 0.60 g Pb(NO3)2 can be added to 1.5 L of 0.100 M NaBr(aq) without forming a precipitate. Calculate the ksp of PbBr2. 5. Consider the following solutions at 25 oC Saturated AgCl(aq) Saturated Ag2CO3(aq) Using calculations, identify the solution with the greater [Ag+]. Solubility Unit Plan Notes- double click on the lesson number and download Power Point Viewer if you do not have it. Worksheets Quiz 1. Solubility and Saturated Solutions. WS 1 1 2. Ion Concentration Calculations and Ionic Equations. WS 2-3 2 3. Solubility to Ksp. WS 4 3 4. Ksp to Solubilty and Size of Ksp. WS 5 4 5. Trial Ksp. WS 6 5 6. Separating Ions WS 7 6 7. Common Ion Effect and WS 8 7 8. Titrations and Max Ion Concentration 8 Quizmebc WS 9 Web Review 9. Review Practice Test1 10. Review Practice Test 2 11. Test Text book Hebden Read Unit III The following workbook is designed to ensure that you can demonstrate your understanding of all aspects of the solubility unit. Ask yourself, “do I want to do well in this class?” If you are determined to be successful the minimum expectation that you should have for yourself is that you do all of these questions by the due dates given by your teacher. There are other things that you should do to prepare for the test at the end of the unit. Remember, what you put into this course is what you will get out. There is no substitute for consistent effort and hard work. If you can’t do a question, get some help before the end of the unit, you need to know, understand, and remember everything. Good luck! I know you can do well in this unit. Keep up the great work! Web Site Address: http://www.wjmouat.com/ Chemistry 12 Solubility and Saturated Solutions 1. Define and give units for solubility. M, g/100mL, WS #1 g/L 2. Describe the relationship between the rate of dissolving and the rate of crystallization when a small amount of solute is added to an unsaturated solution. Rate of dissolving is greater than the rate of crystallization 3. Describe the relationship between the rate of dissolving and the rate of crystallization when a small amount of solute is added to a saturated solution. Rate of dissolving equals the rate of crystallization 4. Describe the relationship between the rate of dissolving and the rate of crystallization when a small amount of solute is added to a supersaturated solution. Rate of dissolving is less than the rate of crystallization 5. Which of the above solutions would need to be prepared in order to determine the solubility of an ionic solution. Saturated 6. 2.65 g of Ba(OH)2 is dissolved in 70.0 mL of water to produce a saturated solution at 20 oC. Calculate the solubility in units of g/100 mL, g/L, and M. 0.221M 37.9g/L 3.79g/100mL 7. A beaker containing 100. mL of saturated BaCO3 solution weighs 159.60 g. The beaker is evaporated to dryness and weighs 56.36 g. The empty beaker weighs 24.33 g. Calculate the solubility in units of g/100 mL, g/ L, and M. 56.36 g 32.03g = 320g x 1 mole Do not use the mass with water included! - 24.33g 100 mL L 197.3g 32.03 g = 1.62 M 8. Write dissociation equations to represent the equilibrium present for a saturated solution of each ionic compound. Write the solubility product (Ksp expression) for each of the equilibrium systems. The first one is done. a) Al2(SO4)3 ⇄ 2Al3+ + 3SO42- Ksp = [Al3+]2 + CO32- Ksp = [Fe2+] [SO42-]3 b) FeCO3 [CO32-] ⇄ Fe2+ c) Co2(SO4)3 ⇄ 2Co3+ + 3SO42- Ksp = [Co3+]2 ⇄ + PO43- Ksp = [Na+]3 [SO42-]3 d) Na3PO4 3Na+ [PO43-] 10. Write formula, complete ionic, and net ionic equations for each. a) H2SO4(aq) NaOH(aq) → + H2SO4 (aq) + 2NaOH (aq) → 2H2O (l) 2H+(aq) + SO42-(aq) + 2Na+(aq) + 2OH-(aq) → + Na2SO4 (aq) 2H2O (l) + 2Na+(aq) + SO42-(aq) 2H+(aq) + 2OH-(aq) b) Mg(NO3)2(aq) + → 2H2O (l) Na2CO3(aq) → Mg(NO3)2 (aq) + Na2CO3 (aq) → MgCO3 (s) + 2NaNO3 (aq) Mg2+(aq) + 2NO3-(aq) + 2Na+(aq) + CO32-(aq) → MgCO3 (s) + 2Na+(aq) + 2NO3 - (aq) Mg2+(aq) c) Al(NO3)3(aq) + + CO32-(aq) → MgCO3 (s) (NH4)3PO4(aq) → Al(NO3)3 (aq) + (NH4)3PO4 (aq) → AlPO4 (s) + 3NH4NO3 (aq) Al3+(aq) + 3NO3-(aq) + 3NH4+(aq) + PO43-(aq) → AlPO4 (s)+ 3NH4+(aq) + 3NO3 - (aq) Al3+(aq) + PO43-(aq) → AlPO4 (s) d) H3PO4(aq) + Ca(OH)2(aq) → 2H3PO4(aq) + 3Ca(OH)2(aq) → Ca3(PO4)2(s) + 6HOH(l) 6H+ (aq) + 2PO43-(aq) + 3Ca2+(aq) + 6OH-(aq) → Ca3(PO4)2(s) 6H+ (aq) + 2PO43-(aq) + 3Ca2+(aq) + 6OH-(aq) → Ca3(PO4)2(s) Chemistry 12 1. Solubility WS #2 + 6HOH(l) + 6HOH(l) Ion Concentration Calculations What is the concentration of each ion in a 10.5 M sodium silicate solution? Na2SiO3 ⇄ 2Na+ + SiO32- 10.5 M 21.0 M 10.5 M [Na+] = 21.0 M, [SiO32-] = 10.5 M 2. What is the concentration of each ion in the solution formed when 94.5 g of nickel (III) sulphate is dissolved into 850.0 mL of water? Molarity = Ni2(SO4)3 94.5 g x ⇄ 1 mole 405.7g 0.850L 2Ni3+ = + 0.2740 0.548 M [Ni3+] = 0.548 M, [SO42-] = 0.822 M 0.2740 3SO420.822 M 3. If 3.78 L of 0.960 M sodium fluoride solution is added to 6.36 L of 0.550 M calcium nitrate solution, what is the resulting concentration of [Ca+2] and [F-]? NaF Ca(NO3)2 ⇄ 3.78 x 0.960 M = 6.36 x 0.550 M = 10.14 10.14 [Ca2+] = 0.345 M, ⇄ Na+ + F- Ca2+ + 2NO3- 0.358 M 0.345 M 0.358M 0.690M [F-] = 0.358 M 4. What is the concentration of each ion in the solution formed when 94.78 g of iron (III) sulphate is dissolved into 550.0 mL of water? [Fe3+] = 0.8619 M, [SO42-] = 1.293 M 5. If the [F-] = 0.200 M, calculate the number of grams AlF3 that would be dissolved in 2.00 L of water. AlF3 ⇄ 0.06667M Al3+ 3F- + 0.06667M 2.00L x 0.06667 mole x L 84.0 g mole = 0.200M 11.2g 6. If the [SO42-] = 0.200 M in 2.0 L of Al2(SO4)3, determine the [Al3+] and the molarity of the solution. Al2(SO4)3 ⇄ 0.067 M 2Al3+ + 3SO42- 0.13 M 0.20 M Dissociation Equations Write a dissociation equation for any chemical which dissociate when dissolved in water: 1. HCl (aq) ⇄ H+ + Cl- 2. Na2S (s) ⇄ 2 Na+ (aq) + S2- (aq) 3. Al(CH3COO)3 (s) ⇄ Al3+ (aq) + 3CH3COO- (aq) 4. MgBr2 (s) ⇄ Mg2+ (aq) + 2 Br- (aq) 5. Na2CO3 (s) ⇄ 2 Na+ (aq) + CO32- (aq) 6. C12H22O11 (s) compounds do not dissociate) 7. K3PO4 (s) 8. CH3OH (l) compounds do not dissociate) Net Ionic Equations ⇄ C12H22O11 (aq) ⇄ 3 K+ (aq) ⇄ CH3OH (aq) (molecular + PO43- (aq) (molecular Write chemical equations, total ionic equations and net ionic equations for each reaction. The first one is done for you. (assume that all reactions occur): 1. Magnesium metal is placed in hydrochloric acid Mg (s) + 2 HCl (aq) → Mg (s) + 2 H+ (aq) + 2 Cl- (aq) → Mg (s) + 2 H+ (aq) → MgCl2 (aq) + H2 (g) Mg2+ (aq) + 2Cl- (aq) + H2 (g) Mg2+ (aq) + H2 (g) 2. Zinc metal is placed in silver nitrate solution Zn (s) + 2Ag NO3 (aq) → Ag (s) + + Zn(s) + 2Ag (aq) + 2 NO3-(aq) → 2NO3-(aq) Zn(s) 3. Zn+2 (aq) + 2Ag(s) Barium chloride solution is added to lead (II) nitrate solution. + Pb(NO3)2 (aq) → PbCl2 (s) BaCl2 (aq) Ba2+(aq) 2NO3 → 2Ag+ (aq) + 2 Zn(NO3)2 (aq) 2Ag(s) + Zn+2 (aq) + + - Ba2+ (aq) (aq) 2Cl- (aq) + → PbCl2 (s) Sulphuric acid is added to Strontium hydroxide solution. H2SO4 (aq) + Sr(OH)2 (aq) → 2H+(aq) + SO42-(aq) + Sr2+(aq) + 2OH-(aq) 2H2O (l) → 2H+(aq) + SO42-(aq) + Sr2+(aq) + 2OH-(aq) 5. Ba(NO3)2 (aq) + 2Cl-(aq) + Pb2+(aq) + 2NO3-(aq) → PbCl2 (s) + Pb2+ (aq) 4. + + SrSO4 (s) 2H2O (l) + SrSO4 (s) → 2H2O (l) + SrSO4 (s) Sodium carbonate solution is added to nickel (III) nitrate solution. 3Na2CO3(aq) + 2Ni(NO3)3 (aq) → Ni2(CO3)3 (s) + 6NaNO3 (aq) 6Na+(aq) +3CO32-(aq) +2Ni3+(aq) +6NO3-(aq) → Ni2(CO3)3 (s) + 6Na+(aq) +6NO3-(aq) 3CO32-(aq) 6. Cl2 (aq) + 2Ni3+(aq) → Ni2(CO3)3 (s) Aqueous chlorine is added to sodium bromide solution. + 2NaBr (aq) → 2NaCl (aq) + Br2 (aq) Cl2 (aq) + 2Na+ (aq) + 2Br- (aq) → 2Na+ (aq) + 2Cl- (aq) + Br2 (aq) + Cl2 (aq) 7. + 2Br- (aq) → 2Cl- (aq) + Br2 (aq) Nitric acid is added to aluminum hydroxide solution. 2HNO3 (aq) + Sr(OH)2 (aq) → 2H2O (l) 2H+(aq) + 2NO3-(aq) + Sr2+(aq) + + 2OH-(aq) Sr(NO3)2 (aq) → 3H2O (l) + Sr2+(aq) + 2NO3- (aq) H+(aq) + OH-(aq) → H2O (l) WS # 3 1. Classify each as an ionic or molecular (covalent) solution. NaCl (aq) __________Ionic NH3 (aq) __________ molecular CoCl2 (aq) _________ Ionic AgCl (aq) _________ Ionic CH3OH (aq) ________ molecular HCl (aq) __________ Ionic (although this is a covalent compound when gaseous, it ionizes in solution) NH4OH (aq) ________ Ionic I2 (aq) ___________ molecular 2. Define each: a) unsaturated solution: contains less than the maximum amount of dissolved solute b) saturated solution: contains the maximum amount of dissolved solute c) solubility: the maximum amount of solute the can dissolve in a given amount of solution (M, g/L, or g/100mL). 3. Describe how you would prepare a saturated solution. Add measured increments of solute to a given volume of water until it no longer dissolves. Add the mass of the solute added and divide by the volume of solution. 4. Describe how you would determine the solubility of NaCl in water at 20oC. Add measured increments of NaCl to 100 mL of water until it no longer dissolves. Add the mass of the solute and divide by 0.100 L of solution. 5. In terms of equilibrium describe the difference between a saturated and unsaturated solution. A saturated solution is at equilibrium and an unsaturated solution is not. 6. What is the effect of temperature on solubility? Increasing the temperature usually increases the solubility. 7. 200g of CoCl2 is dissolved in 500.0 mL of water at 0oC to form a saturated solution. What is the solubility of CoCl2 at 0oC in three different units? Molarity 129.9 g = = 200g x 1 mole 129.9g = 3.08 M 400 g/L = 40.0 g/100mL 0.500 L 3.0793 mole x L 1 mole 8. In a saturated solution of CaCl2, a small amount of solid is present. Write a net ionic equation showing the equilibrium reaction. Write the solubility product (Ksp expression) CaCl2 <------> Ca2+ 2Cl- + Ksp = [Ca2+][Cl-]2 9. If you were given a saturated, unsaturated and supersaturated solution, how would you distinguish one from another? a) Unsaturated solution: add some solute and it will dissolve b) Saturated solution: add some solute and it will not dissolve c) Supersaturated solution: add some solute and it will cause more crystallization 10. Write the equilibrium equation and solubility product Ksp for each salt. The first one is done. a) Ca(OH)2 (s) ⇄ b) AgCl (s) ⇄ Ag+ + c) Na3PO4 (s) ⇄ d) (NH4)3PO4 (s) ⇄ e) Cu2SO4 (s) ⇄ f) Al(CH3COO)3 (s) ⇄ Al+3 + 3CH3COO- Ksp = [Al+3] [CH3COO-]3 g) Ca3(PO4)2 (s) ⇄ + 2PO4-3 Ksp = [Ca+2]3 [PO4-3]2 Chem 12 WS #4 Ca2+ + 2OH- Cl- 3Na+ Ksp = [Ag+] [Cl-] + 3NH4+ 2Cu+1 3Ca+2 Ksp = [Ca2+] [OH-]2 PO4-3 + PO4-3 SO4-2 + Solubility to Ksp Ksp = [Na+]3 [PO4-3] Ksp = [NH4+]3 [PO4-3] Ksp = [Cu+1]2 [SO4-2] The Ksp is a measure of the solubility of an ionic salt. The larger the value of the Ksp, the greater is the solubility of the salt. You can only calculate a Ksp if the solution is saturated. Only saturated salt solutions are in equilibrium. You can calculate the Ksp from the solubility of a salt, since the solubility represents the concentration required to saturate a solution. 1. Calculate the Ksp for CaCl2 if 200.0 g of CaCl2 are required to saturate 100.0 mL of solution. Molarity = 200 g x 1 mole 111.1 g 0.100L CaCl2 ⇄ 18.0 M 18.0 M 36.0M Ca2+ + = 18.001 M 2Cl- Ksp = [Ca2+][Cl-]2 Ksp = [18.0][36.0]2 Ksp = 2.33 x 104 2. Calculate the Ksp for AlCl3 if 100.0 g is required to saturate 150.0 mL of a solution. Ksp = 1.679 x 104 3. The solubility of SrF2 is 2.83 x 10-5 M. Calculate the Ksp. Ksp = 9.07 x 10-14 4. The solubility of GaBr3 is 15.8 g per 100 mL. Calculate the Ksp. Molarity = 15.8 g x 1 mole 309.4 g 0.100 L = 0.51066 M ⇄ GaBr3 0.51066 M Ga3+ 0.51066 M + 3Br- 1.532 M Ksp = [Ga3+][Br-]3 Ksp = [0.51066][1.532]3 Ksp = 1.83 5. The solubility of Ag2SO4 is 1.33 x 10-7g per 100 mL. Calculate the Ksp. Ksp = 3.10 x 10-25 6. If 2.9 x 10-3 Ca(OH)2 g is needed to saturate 250 mL of solution, what is the Ksp. Ksp =1.5 x 10-11 7. At a certain temperature, a 40.00 mL sample of a saturated solution of barium hydroxide, is neutralized by 29.10 mL of 0.300 M HCl. Calculate the Ksp of Ba(OH)2. 2HCl 0.02910 L 0.300 M + Molarity Ba(OH)2 1 mole Ba(OH)2 Ba(OH)2 0.0400 L ?M = → BaCl2 + 0.02910 L HCl x 2HOH 0.300 moles 1L 2 moles HCl 0.0400 L = Ba(OH)2 0.1091 M ⇄ 0.109 M Ba2+ 0.1091 M + 2OH0.2183 m x Ksp = [Ba2+][OH-]2 Ksp = [0.1091][0.2183]2 = 5.20 x 10-3 Calculate the concentrations of all ions in each solution. 8. 0.50 M Al2(SO4)3(aq) Al2(SO4)3 ⇄ 2Al3+ 0.50 M 1.0 M [Al3+] = 1.0M + 3SO421.5 M [SO42-] = 1.5M 9. 25.7g (NH4)3PO4 (aq) in 250mL H2O. [NH4+] = 2.07M [PO43-] = 0.690M 10. 210g CoCl2 • 6H2O in 800mL H2O. [Co2+] = 1.10M [Cl-] = 2.20M Chemistry 12 Ksp to Solubility WS # 5 Calculate the solubility in M and g/L for each. Use the Ksp values found in your chart. 1) BaCO3 BaCO3(s) ⇄ x x ksp = [Ba2+][ CO32-] ksp = x2 Ba2+ + x CO32- 2.6 x 10-9 = x2 5.099 x 10-5 M 5.099 x 10-5 mole x 197.3 g L 1 mole = 1.0 x 10-2 g/L 2) Fe(OH)2 2.1 x 10-4 g/L 3) PbCl2 4.0 g/L 4) How many grams of Mg(OH)2 are required to completely saturate 1.5 L of solution? Mg(OH)2 ⇄ x Mg2+ + 2OH- x 2x Ksp = [Mg2+][OH-]2 Ksp = [x][2x]2 Ksp = 4x3 5.6 x 10-12 = 4x3 1.119 x 10-4 M = x 1.5 L x 1.119 x 10-4 mole x 58.3 g = 9.8 x 10-3 g 1L 1 mole Review 1. If 200 g of MgCl2 is required to saturate 1.5 L of solution at 20 oC, calculate the Ksp. Ksp = 11 2. 2. If the Ksp for Al2O3 is 2.8 x 10-8, calculate [Al3+] and [O-2] in [Al+3] = 2.4 x 10-2 M Trial Ksp mol /L. [O-2] = 3.6 x 10-2 M Worksheet 6 1. Will a precipitate form if 200ml 0.00020M Ca(NO3)2 is mixed 300ml of 0.00030M Na2C03? CaCO3 ⇄ Ca2+ + CO32- 200 x 0.00020 M 500 300 x 0.00030 M 500 0.000080 M 0.00018 M Trial Ksp = [0.000080][0.00018] Trial Ksp = 1.4 x 10-8 > Ksp(5.0 x 10-9) Therefore a precipitate forms! 2. Will a precipitate form if 25.0ml of .0020M Pb(NO3)2 is mixed with 25.0ml of .040M NaBr. Trial ksp = 4.0 x 10-7 no ppt 3. Will a precipitate form if equal volumes of 0.00020M Ca(NO3)2 is mixed with 0.00030M Na2C03? Note: When equal volumes are mixed the dilution factor is ½ for each ion. Trial ksp = 1.5 x 10-8 ppt > Ksp and there is a precipitate Ksp 4. Co(OH)2 Solubility = 3.0x10-3 g/L Ksp=? ksp = 1.3 x 10-13 5. Ag2C2O4 Solubility = 8.3x10-4 M Ksp=? ksp = 2.3 x 10-9 Solubility 6. SrF2 Solubility in (M) = ? 1.0 x 10-3 M 7. Cu(IO3)2 Solubility (g/L) = ? 1.1 g/L Separation Positive Ions: Work from top to bottom of solubility chart!! 7 1. Ag+ Mg2+ Ba2+ i) Add: Ag+ NaCl(aq) Filter Out: AgCl(s) Net Ionic equation: Filter Out: BaSO4(s) Net Ionic equation: Mg(OH)2(s) Net Ionic equation: + Cl- ------> AgCl(s) ii) Add: Ba2+ Na2SO4(aq) + SO4-2 ------> BaSO4(s) iii) Add: NaOH(aq) Filter Out: Mg2++2OH-------> Mg(OH)2(s 2. WS # Pb2+ Ba2+ Sr2+ i) Add: Pb+2 NaCl(aq) Filter Out: PbCl2(s) Net Ionic equation: Filter Out: Ba(OH)2(s) Net Ionic equation: Filter Out: Sr3(PO4)2(s) Net Ionic equation: Filter Out: CuCl(s) Net Ionic equation: Filter Out: Ca(OH)2(s) Net Ionic equation: Sr3(PO4)2(s) Net Ionic equation: Filter Out: AgCl(s) Net Ionic equation: Filter Out: SrSO4(s) Net Ionic equation: Filter Out: Be(OH)2(s) Net Ionic equation: Filter Out: PbCl2(s) Net Ionic equation: CaSO4(s) Net Ionic equation: + 2Cl- ------> PbCl2(s) ii) Add: NaOH(aq) Ba2++2OH-------> BaOH)2(s) iii) Add: Na3PO4(aq) 3Sr2++2PO4-3------> Sr3(PO4)2(s) Cu+ 3. i) Add: Cu+ Ca2+ Sr2+ NaCl(aq) + Cl- ------> CuCl(s) ii) Add: NaOH(aq) Ca2++2OH-------> Ca(OH)2(s) iii) Add: Na3PO4(aq) Filter Out: 3Sr2++2PO4-3------> Sr3(PO4)2(s) Be2+ 4. i) Add: Ag+ Sr2+ Ag+ NaCl(aq) + Cl- ------> AgCl(s) ii) Add: Sr2+ Na2SO4(aq) + SO4-2 ------> SrSO4(s) iii) Add: NaOH(aq) Be2++2OH-------> Be(OH)2(s) 5. Be2+ i) Add: Pb+2 Pb2+ NaCl(aq) + 2Cl- ------> PbCl2(s) ii) Add: Ca2+ Ca2+ Na2SO4(aq) Filter Out: + SO4-2 ------> CaSO4(s) iii) Add: NaOH(aq) Filter Out: 2+ Be +2OH ------> Be(OH)2(s) Be(OH)2(s) Net Ionic equation: ] 6. Calculate the Ksp for CaCl2, if 50.0 g is required to saturate 25.0 mL of water. 50.0 g x 1 mole 111.1 g 2.33 x 104 0.0250 L = Ksp = 4x3 18.0 M = 4(18.0)3 = 7. Calculate the molar solubility of Mg(OH)2. Mg(OH)2 x ⇄ Mg2+ + x 2OH2x 4x3 = 5.6 x 10-12 x = 1.1 x 10-4 M 8. Will a precipitate form if equal volumes of 0.00020 M Na2CO3 is mixed with 0.00020 M MgCl2. MgCO3(s) ⇄ Mg2+ + ½ (0.00020 M) 0.00010 M Trial Ksp = [Mg2+][CO32-] (0.00010)(.00010) 1 x 10-8 Trial Ksp < Ksp = 6.8 x 10-6 9. CO32½ (0.00020 M) 0.00010 M no ppt Write the formula, complete, and net ionic equation. Formula Equation: CaCl2(aq) + 2AgNO3(aq) → Ca(NO3)2(aq) + Complete Ionic: + 2AgCl(s) Ca2+ + 2Cl- + 2Ag+ + 2NO3- → 2AgCl(s) Ca2+ + 2NO3- Net Ionic: 1. SO32- OH- i) Add: Ag+ + Cl- → Filter Out: SrSO3(s) Net Ionic equation: Zn(OH)2(s) Net Ionic equation: Filter Out: AgI(s) Net Ionic equation: Filter Out: SrCO3(s) Net Ionic equation: Zn(OH)2(s) Net Ionic equation: Sr3(PO4)2(s) Net Ionic equation: ZnS(s) Net Ionic equation: AgCl(s) I- Sr(NO3)2(aq) Sr2+ + SO32- ---->SrSO3(s) ii) Add: Zn(NO3)2(aq) Filter Out: Zn2+ + 2OH- ----> Zn(OH)2(s) iii) Add: AgNO3(aq) Ag+ + I- ---->AgI(s) 2. CO32- OH- i) Add: Sr(NO3)2(aq) Sr2+ + CO32- ---->SrCO3(s) ii) Add: Zn(NO3)2(aq) Filter Out: Zn2+ + 2OH- ----> Zn(OH)2(s) 3. Br- i) Add: S2- PO43- Sr(NO3)2(aq) Filter Out: 3Sr2+ + 2PO43- ----> Sr3(PO4)2(s) ii) Add: Zn(NO3)2(aq) Filter Out: Zn2+ + 2S-2 ----> ZnS(s) iii) Add: equation: 4. AgNO3(aq) Filter Out: Ag+ + Br- ---->AgBr(s) PO43- OH- S2- AgBr(s) Net Ionic i) Add: Sr(NO3)2(aq) Filter Out: Sr3(PO4)2(s) Net Ionic equation: Mg(OH)2(s) Net Ionic equation: ZnS(s) Net Ionic equation: Mg(OH)2(s) Net Ionic equation: BaSO4(s) Net Ionic equation: ZnS(s) Net Ionic equation: BaSO4(s) Net Ionic equation: ZnS(s) Net Ionic equation: AgCl(s) Net Ionic equation: 3Sr2+ + 2PO43- ----> Sr3(PO4)2(s) ii) Add: Mg(NO3)2(aq) Filter Out: Mg2+ + 2OH- ----> Mg(OH)2(s) iii) Add: Zn(NO3)2(aq) Filter Out: Zn2+ + 2S-2 ----> ZnS(s) 5. OH- i) Add: S2- SO42- Mg(NO3)2(aq) Filter Out: Mg2+ + 2OH- ----> Mg(OH)2(s) ii) Add: Ba(NO3)2(aq) Filter Out: Ba2+ + SO42- ---->BaSO4(s) iii) Add: Zn(NO3)2(aq) Filter Out: Zn2+ + 2S-2 ----> ZnS(s) 6. S2- i) Add: SO42- ClBa(NO3)2(aq) Filter Out: Ba2+ + SO42- ---->BaSO4(s) ii) Add: Zn(NO3)2(aq) Filter Out: Zn2+ + 2S-2 ----> ZnS(s) iii) Add: AgNO3(aq) Filter Out: Ag+ + Cl- ---->AgCl(s) Common Ion Effect Worksheet # 8 Consider the following equilibrium system. PbCl2(s) ⇌ Pb2+(aq) + 2 Cl-(aq) Describe what happens to the solubility of PbCl2 after each of the changes are made. Solu 1. PbCl2(s) is added no c 2. Pb(NO3)2 is added decr 3. NaCl is added decr 4. H2O is added (remember that solubility is moles per litre) no c 5. AgNO3 is added (Ag+ reacts with Cl- to form AgCl(s) which has low solubility) increases 6. NaBr is added (Br- reacts with Pb2+ to form PbBr2(s) which has low solubility) increases AgBr(s) ------> Ag+(aq) Consider the following equilibrium system. + Br-(aq) Describe what happens to the solubility of PbCl2 after each of the changes are made. 7. AgBr(s) is added 8. Pb(NO3)2 is added Pb2+ reacts with Br- to form PbBr2(s) which has low solubility 9. NaCl is added (Ag+ reacts with Cl- to form AgCl(s) which has low solubility) 10. H2O is added (remember that solubility is moles per litre) 11. AgNO3 is added decreases 12. NaBr is added decreases 13. Explain why more Zn(OH)2(s) dissolves when 3 M HCl is added to a saturated solution of Zn(OH)2. Start by writing the correct equilibrium equation. Zn(OH)2(S) ⇌ Zn2+ + 2OH- The HCl increases the concentration of H+ which reacts with OH- lowering the [OH-]. This causes the above equilibrium to shift to the right and more Zn(OH)2(S) dissolves. 14. In an experiment, 0.1 M AgNO3 is added to 0.1 M NaCl, resulting in the formation of a white precipitate. When 0.1 M NaI is added to this mixture, the precipitate dissolves and a yellow precipitate forms. white The formula for the white precipitate is AgCl The formula for the yellow precipitate is AgI The net ionic equation for the first equilibrium is ⇌ AgCl(s) Ag+ + Cl- The net ionic equation for the formation of the yellow precipitate is + I→ AgI(s) Ag+ Explain why the white precipitate dissolves. Start by writing the equilibrium equation for the white precipitate, then, explain how adding NaI affects this equilibrium. ⇌ AgCl(s) Ag+ + Cl- The NaI increases the concentration of I- which reacts with Ag+ lowering the This causes the above equilibrium to shift to the right and AgCl(s) dissolves. [Ag+]. Titrations and Maximum Ion Concentration Worksheet # 9 1. In a titration 25.0ml of a 0.250M AgNO3 solution was used to precipitate out all of the Br- in a 200 ml sample. Calculate [Br-]. Ag+ + 0.0250 L 0.250 M Br- → AgBr(s) 0.200 L ?M 0.0250 L 1 mole Br[Br-] = 1 mole Ag+ x 0.250 mole 1L 0.200 L [Br-] = 0.0313M x 2. In a titration 26.5ml of .100M Pb(NO3)2 was used to precipitate out all of the Clin a 30.0 ml sample of water. Calculate [Cl-]. [Cl-] = 0.177 M Maximum Ion Concentration 3. Calculate the maximum concentration of OH- that can exist in a 0.200 M Mg(N03)2 solution. Mg(OH)2(s) ⇄ Mg2+ + 2OH- 0.200 M [OH-] Ksp = [Mg2+][OH-]2 5.6 x 10-12 = [0.200][OH-]2 [OH-] = 5.3 x 10-6 M 4. Calculate the maximum concentration of CO3-2 that can exist in a .500M AgNO3 solution. [CO3-2] = 3.4 x 10-11 M 5. Calculate the maximum concentration of IO3- that can exist in a .200M Cu(N03)2 solution. [IO3-] = 5.9 x 10-4 M 6. Calculate the maximum concentration of Ca+2 that can exist in a .200M Na2C03 solution. [Ca2+] = 2.5 x 10-8 M 7. Calculate the minimum number of moles of Pb(NO3)2 required to start precipitation in 50.0 mL of 0.15 M ZnCl2. PbCl2 ⇄ Pb2+ + [Pb2+] 2Cl0.30 M Ksp = [Pb2+][ Cl-]2 Don’t forget to multiple 0.15 M by 2 due to ZnCl2 1.2 x 10-5 = [Pb2+][ 0.30]2 [Pb2+] = 1.33 x 10-4 M 0.0500 L x .000133 moles = 6.7 x 10-6 moles L 8. In a titration 12.5 mL of 2.00 x 10-5 M HCl is required to neutralize 250 mL of saturated AgOH solution. Calculate the [OH-] and then determine the Ksp for AgOH. Ag+ + .250 L ?M Cl→ .0125 L .00002 M [Ag+] = 0.0125 L Cl- x AgCl(s) Cl0.250 L 0.00002 moles x L 1 mole Ag+ 1 mole = 1.0 x 10-6 M AgOH(s) 1.0 x 10-6 M ⇄ Ag+ + 1.0 x 10-6 M Ksp = [Ag+][OH-] Ksp = (1.0 x 10-6 )2 Ksp = 1.0 x 10-12 OH1.0 x 10-6 M 9. When excess Ag2CO3(s) is shaken with 1.00 L of 0.200 M K2CO3 it is determined that 6.00 x 10-6 moles of Ag2CO3 dissolves. Calculate the solubility product of Ag2CO3. Ag2CO3(s) ⇄ 2Ag+ 6.00 x 10-6 M x2 1.20 x 10-5M This molarity is determined by the soluble K2CO3 There is a 2 in the formula Ag2CO3 Ksp = [Ag+]2[CO32-] = [1.20 x 10-5]2[0.200] = 2.88 x 10-11 + CO320.200 M