ANITA S WORK H I4 6 I6 5

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1 ANITA S WORK Multiple Choice Section: Please DO NOT WRITE or MAKE ANY MARKS on this test paper. Put all answers on your SCANTRON CARD. Please make sure that you fill in your Scantron Card correctly: use pencil, fill in the little boxes completely, but don t go beyond the border. Don t put any extraneous marks anywhere on the card. Don t press too hard, and make sure that you erase all mistakes completely. Think hard and Good Luck! I H a) Write the balanced formula equation for the reaction between Na 3 PO (aq) and CuCl 2(aq). (1mark) b) Write the net ionic equation for the reaction between Na 3 PO (aq) and CuCl 2(aq). (1mark) A saturated solution of nickel carbonate, NiCO 3, contains 0.090g in 2.0L of solution. Calculate K sp for NiCO 3. (3marks) Calculate the maximum concentration of Pb 2+ that can exist in M Na 2 SO without forming a precipitate. (2marks) Consider the following: a) Which two solid samples could be added to the CaS solution in order to remove first one ion and then the other from the solution. Indicate the order in which to add them. (2marks) First add: Then add: H2 I I G I b) Write the net ionic equation for one of the precipitation reactions in part a). A 100 ml solution containing 0.2 M Al +2, 0.2 M NH +, and 0.2 M Mg 2+ is added to a 100 ml solution containing 0.2 M S -2, 0.2 M Cl -, and 0.2 M OH -.Identify the ions that do not form a precipitate. (2 marks) A science teacher needs.0 L of limewater for an experiment. Limewater is a saturated solution of Ca(OH) 2. Calculate the minimum mass of Ca(OH) 2 required to make this solution. K sp ( marks) A suspension of barium sulphate is used to improve the quality of X-rays in the digestive system. If a patient is required to drink 0.00 L of this suspension, calculate the actual mass in grams of dissolved BaSO. (K sp of BaSO = ). ( marks) Write an equation that describes the equilibrium present in a saturated solution of Cu 3 (PO ) 2. (2 marks) A 1.0 M solution of sodium sulphite is added to a 1.0 M solution of copper(ii) chloride resulting in the formation of a precipitate. a) Identify the precipitate. b) Write the complete ionic equation for the reaction. c) Identify all spectator ions. In an experiment, ml samples containing silver ions are titrated with M KSCN. The equation for the reaction is Ag + (aq) + SCN - (aq) AgSCN (s) The following data are recorded. Calculate the concentration of the silver ion in the solution. ( marks) RAYCROFT 2 - Solubility Study Guide - Written - Page 1 of 11

2 I I G Calculate the maximum moles of Br - that can exist in 0.00 L of 0.10 M Pb(NO 3 ) 2. ( marks) Will a precipitate form if 30.0mL of 0. M Ca(NO 3 ) 2 is mixed with 0.0mL of M Na 2 SO? ( marks) In an experiment, a student pipettes a sample of saturated MgBr 2 solution into a beaker and evaporates the sample to dryness. He recorded the following data: G I Calculate the solubility of MgBr 2 in moles per litre. (3marks) What is the solubility of CaCO 3 in g/l? (3 marks) A saturated solution of BaSO is given to patients needing digestive tract x-rays. a) Write an equation that represents the solubility equilibrium. (1mark) b) Calculate the [Ba 2+ ] present in the saturated solution. (2marks) Will a precipitate form when 90.0 ml of M Cu (NO 3 ) 2 and 10.0 ml of M NaIO 3 are mixed? Explain using appropriate calculations. (3marks) Write a balanced chemical equation for the equilibrium in a saturated solution of an ionic compound with low solubility. (2marks) A saturated solution of AgCH 3 COO was evaporated to dryness. The 20.0 ml sample was found to contain 1.8 g AgCH 3 COO. Calculate the solubility product constant for AgCH 3 COO. (marks) A 2.00 ml sample of a saturated ZnF 2 solution was evaporated to dryness. The mass of the residue was 0. g. Calculate the solubility product constant of ZnF 2. (marks) The following data were collected when a 2.00 ml sample of water containing chloride ion was titrated using M AgNO 3 to completely precipitate the chloride ion. H a) Write the net ionic equation for the precipitation reaction. (1mark) b) Calculate the [Cl - ]. (3marks) a) Identify a compound that could be used to precipitate both the Mg 2+ (aq) and Ca 2+ (aq) from hard water. (1mark) b) Write the net ionic equations for the reactions. (2 marks) How many grams of CaSO (Plaster of Paris) are dissolved in ml of a saturated CaSO solution at 2 C? (3marks) A saturated solution of BaF 2 has a [Ba 2+ ] of M. Calculate the K sp value. (2 marks) Calculate the maximum mass of Na 2 SO which can be dissolved in 2.0 L of 1. M Ca(NO 3 ) 2 without a precipitate forming. (3 marks) RAYCROFT 2 - Solubility Study Guide - Written - Page 2 of 11

3 H I I A solution contains 0.20 M Cl and 0.20 M SO. a) Identify a cation that could be added to the solution to give a precipitate with only one of these anions. b) Write the net ionic equation for the precipitation reaction in part a). Will a precipitate form when 2.0 ml of 0.1 M AgNO 3 is added to 1.0 ml of 0.20 M NaCl? Support your answer with appropriate calculations. (3 marks) a) Write the net ionic equation for the precipitation reaction that occurs when solutions of NaIO 3 and AgNO 3 are mixed. b) Using appropriate calculations, explain why a precipitate forms when 1.0 ml of 0.0 M NaIO 3 are added to 3.0 ml of 0.0 M AgNO 3. (3 marks) What is the maximum [CO 3 ] that can exist in a M AgNO 3 solution? (2 marks) A container is filled with 10.0 L of 0.00 M NaI. Calculate the maximum mass of solid Pb(NO 3 ) 2 that can be dissolved without forming a precipitate. (3 marks) Write net ionic equations for all precipitation reactions that occur when equal volumes of 0.20 M Sr(OH) 2 and 0.20 M MgSO are mixed together. (2 marks) A ml sample of a saturated solution of Ca(OH) 2 is evaporated to dryness. The mass of the solid residue is 0.12 g. Calculate the solubility product of Ca (OH) 2. ( marks) Write the net ionic equation representing the reaction that occurs when equal volumes of 0.20 M H 2 SO and 0.20 M Ba(NO 3 ) 2 are mixed together. (2 marks) Consider the following reaction: Cu (s) + 2AgCH 3 COO (aq) Cu(CH 3 COO) 2(aq) + 2Ag (s) A piece of Cu wire is placed into 1.00 L of a saturated solution of silver acetate, AgCH 3 COO. When all the Ag + has reacted, 2.00 g of Cu has been used. a) Write the net ionic equation for the reaction between Cu and Ag +. (1mark) b) Calculate the K sp of AgCH 3 COO. (marks) Consider the following net ionic equation: Ag (aq) SCN (aq) AgSCN (s) A ml sample of M NH SCN is used to titrate a ml sample containing Ag +. Calculate the [Ag + ] in the original sample. (3marks) A solution contains M Ba 2+ and an unknown concentration of Sr 2+. When dilute Na 2 CO 3 is slowly added to the mixture, both Ba 2+ and Sr 2+ start to precipitate at the same time. (3 marks) a) Calculate the [CO 3 ] when BaCO 3 starts to precipitate. b) Calculate the initial [Sr 2+ ]. What is the maximum [Mg 2+ ] that can exist in a solution with a poh of 2.00? (3marks) When 1.00 L of a saturated solution of CaF 2 was evaporated to dryness, g of residue was formed. Calculate the value of K sp. (3marks) RAYCROFT 2 - Solubility Study Guide - Written - Page 3 of 11

4 3 38. In an experiment to determine the solubility of barium fluoride, ml of the saturated solution was heated in an evaporating dish to remove the water. The evaporating dish and residue were heated two more times, to ensure all the water had been driven off Using the data above, calculate the K sp for BaF 2. ( marks) Consider the graph below representing the following equilibrium: CH 3 CH 2 CH 2 CH 3 (g) CH 3 CH(CH 3 ) 2 (g) n-butane isobutene Data for the graph was obtained from various equilibrium mixtures. G8 G Calculate the value of K eq for the equilibrium. (2 marks) A ml sample of M Ca (NO 3 ) 2 is diluted by adding 00. 0mL of water. Calculate the concentration of ions in the resulting solution. (2 marks) A maximum of 0.0g Pb (NO 3 ) 2 can be added to 1. L of NaBr (aq) without forming a precipitate. Calculate the[nabr]. ( marks) The solubility of Mn (IO 3 ) 2 is mol/l. a) Write the net ionic equation that describes a saturated solution of Mn (IO 3 ) 2. b) Calculate the concentrations of the ions in a saturated solution of Mn (IO 3 ) 2. Consider the following saturated solutions at 2 C: Using calculations, identify the solution with the greater [Ag + ]. ( marks) RAYCROFT 2 - Solubility Study Guide - Written - Page of 11

5 7. 2Na 3 PO (aq) + 3CuCl 2 (aq) NaCl (aq) + Cu 3 (PO ) 2 (s) 8. 3Cu 2+ (aq) + 2PO 3-(aq) Cu 3 (PO ) 2 (s) [ NiCO 3 ]= 0.090g /2.0 L 1 mol / 118.7g = mol/l NiCO 3 (s) Ni 2+ (aq) + CO M M Ksp = [Ni 2+ ] [CO 3 ] = ( ) ( ) = (Deduct 1/2 mark for incorrect significant figures.) 9. PbSO (s) Pb 2+ + SO (1/2 mark) K sp = [Pb 2+ ][SO ] = (x) ( ) (1. marks) [Pb 2+ ] = x = M 0. First add: NaOH Then add: ZnSO (2 marks) Ca 2+ (aq) + 2OH - (aq) Ca(OH) 2(s) Or Zn 2+ (aq) + S (aq) ZnS (s) 1. NH and Cl (2 marks) 2. K sp for Ca(OH) 2 = Let s = solubility of Ca(OH) 2 = [Ca 2+ ] 2s = [OH - ] Ksp = [Ca 2+ ] [OH - ] = (s)(2s) 2 = s 3 s 3 = s = M (3 marks) MW Ca(OH) 2 = 7.1g/mol (1/2 mark) # g = ( mol/l) (7.1 g/mol) (.0L) = 2.g (1/2 mark) 3... Copper(II) sulphite or CuSO 3 b) 2Na + (aq) + SO 3 (aq) Cu Cl - (aq) CuSO 3(aq) + 2Na + + 2Cl - or Na + (aq) + SO 3 (aq) + Cu 2+ (aq) + Cl - (aq) CuSO 3(s) + Na + (aq) + Cl - (aq) c) Na +, Cl - RAYCROFT 2 - Solubility Study Guide - Written - Page of 11

6 . Average volume = / 2 = 22.0 mol SCN - = L mol/l = mol mol Ag + = mol [Ag + ] = mol / L = 0. 2 M NOTE: Deduct 1 / 2 point for incorrect significant figures. 7. Since Pb(NO 3 ) 2 Pb 2+ - (aq) + 2NO 3 [Pb 2+ ] = 0.10 M (1/2 mark) PbBr 2(s) Pb 2+ (aq) + 2Br - (aq) (1/2 mark) K sp = [Pb 2+ ][Br - ] 2 (1/2 mark) = (0.10 M) [Br - ] 2 (1/2 mark) [Br - ] = M (1mark) mol Br - = M 0.00L = mol (1mark) (- 1/2 mark for incorrect sig. figs. ) 8. [Ca 2+ ] = ml / 90.0 ml = 0.8 M [SO ] = 8.1 M 0.0 ml /90.0 ml =. 10 M TIP = [Ca 2+ ][SO ] = (0.8)( ) = Since trial ion product < K sp,( ), no precipitate will form. 9. Mass of MgBr 2 = 93.7g -89.0g.2g Molar mass of MgBr 2 = 18.1 g/mol Mol MgBr 2 =.2g 1 mol/18.1g = mol Solubility= mol/ L = 0.90 mol/l 70. CaCO 3 Ca 2+ + CO 3 (1mark) Solubility = K sp = mol/l (1mark) = (100.1g / 1 mol) (1mark) = g/l ( 1 / 2 mark) = g/l 71. BaSO (s) Ba 2+ (aq) + SO (aq) b) BaSO (s) Ba 2+ (aq) + SO (aq) [ ] x x K sp = [Ba 2+ ] [SO ] (1/2 mark) = (x) (x) = x 2 [Ba 2+ ] = x = M (1/2 mark) 72. [Cu(NO 3 ) 2 ] = M 90.0mL = M ml [ NaIO 3 ] = M 10.0 ml = M ml Cu(IO 3 ) 2 Cu IO M M TIP = [Cu 2+ ][IO - 3 ] 2 = ( )( ) 2 = TIP ( ) <K sp ( ) -Therefore, a precipitate does not form. 73. AgCl (s) Ag + (aq) + Cl - (aq) RAYCROFT 2 - Solubility Study Guide - Written - Page of 11

7 7. Mol mass AgCH 3 COO = (12.0) + 3(1.0) + 2(1.0) = 1.9g/mol Mol AgCH 3 COO = 1.8g AgCH 3 COO (1mol AgCH 3 COO / 1.9g) = 0.10mol AgCH 3 COO [AgCH 3 COO] = 0.10mol/ 0.20L = 0.1mol/L AgCH 3 COO (2marks) AgCH 3 COO Ag + (aq) + CH 3 COO - (aq) K sp = [Ag + ] [CH 3 COO - ] = (0.1)(0.1) = (2marks) (subtract 1 / 2 mark for incorrect sig. fig) Ag + (aq) + Cl - AgCl (s) Deduct 1 / 2 mark for incorrect significant figures. 77. Add NaOH to precipitate Mg 2+ and Ca 2+. b) Mg 2+ (aq) + 2OH - (aq) Mg(OH) 2(s) Ca 2+ (aq) + 2OH - (aq) Ca(OH) 2(s) 78. CuSO (s) Ca 2+ (aq) + SO (aq) x x K sp = [Ca 2+ ][SO ] = (x)(x) (2 marks) = x 2 x = g CaSO = M 13.2 g/mol L = g RAYCROFT 2 - Solubility Study Guide - Written - Page 7 of 11

8 79. BaF 2(s) Ba 2+ (aq) + 2F - (aq) M M K sp = [Ba 2+ ] [F - ] 2 = ( )( ) 2 = }2 marks 80. CaSO Ca 2+ + SO 1.M x K sp for CaSO = [Ca 2+ ][SO ] = (1.)(x) x = [SO -2 ] = [Ns 2 SO ] = }2 marks mass of Na 2 SO required = mol/l 12.1 g/mol 2.0L = g }2 marks 81. For example: Ca +2 or Sr +2 or Ba +2 b) Ca +2 (aq) + SO (aq) CaSO (s) Sr +2 (aq) + SO (aq) SrSO (s) Ba 2+ (aq) + SO (aq) BaSO (s) 82. [Ag + ] = (2.0mL / 0.0mL) 0.1M = 0.09M ( 1 / 2 mark) [Cl - ] = (1.0mL / 0.0mL) 0.20M = 0.07M ( 1 / 2 mark) TIP (Trial K sp ) = [Ag + ][Cl - ] = (0.09)(0.07) = Since TIP (Trial K sp ) >K sp ( ), a precipitate does form. 83. Ag IO 3 (aq) AgIO 3(s) b)[io - 3 ] = 0.0M (1.0mL / 0.0mL) = 0.1M [Ag + ] = 0.0M (3.0mL / 0.0mL) = 0.3M ( 1 / 2 mark) ( 1 / 2 mark) Trail K sp = [Ag + ][IO 3 - ] = 0.3M 0.1M = 0.02 }1 mark Since Trial K sp 0.02 ( ) > K sp Since Trial K sp (0.02) > K sp ( ), a precipitate forms. 8. 2Ag + + CO 3 (aq) AgCO 3(s) K sp = [Ag + ] 2 [CO 3 ] } 1 / 2 mark = ( ) 2 [CO 3 ] [CO 3 ] = M ( 1 / 2 mark) 1 / 2 mark was deducted for incorrect significant figures 8. PbI 2(s) Pb 2+ (aq) + 2I - (aq) [E] x 0.00 K sp = [Pb 2+ ][I - ] = (x) (0.00) 2 = x = [Pb 2+ ] = M M 331.2g/mol = g/l ( 1 / 2 mark) g/l 10.0L = g ( 1 / 2 mark) 8. Sr 2+ (aq) + SO (aq) SrSO (s) Mg 2+ (aq) + 2OH - (aq) Mg(OH) 2(s) 87. Moles of Ca(OH) 2 = 0.12g (1 mol / 7.1g) = mol Solubility = mol / L = mol/l Ca(OH) 2 Ca OH - K sp = [Ca 2+ ][PH - ] 2 = ( )( ) 2 = (Deduct 1 / 2 mark for incorrect significant figures.) RAYCROFT 2 - Solubility Study Guide - Written - Page 8 of 11

9 88. Ba 2+ (aq) + SO (aq) BaSO (s) (2 marks) 89. Cu (s) + Ag + (aq) Cu 2+ (aq) + 2Ag (s) b) Ag CH 3 COO (s) Ag + (aq) + CH 3 COO - (aq) mol of Cu reacted = 2.00g (1 mol / 3.g) = mol mol Ag + reacted = mol Cu (2 mol Ag + / 1 mol Cu) = mol Ag + } 1 1 / 2 marks) [Ag + ] = [CH 3 COO - ] = M K sp = [Ag + ][CH 3 COO - ] = ( ) 2 = }1 1 / 2 marks 90. mol SCN - = 0.200L (0.200mol / 1L) = mol mol Ag + = mol SCN - = mol } 1 mark [Ag + ] = ( mol / L ) = 0.133M NOTE: ( 1 / 2 mark) is deducted for incorrect significant figures. 91. BaCO 3 Ba 2+ + CO x K sp = [Ba 2+ ][CO 3 ] [CO 2 ] = ( / 0.020) = }1 1 / 2 marks b) SrCO 3 Sr 2+ + CO 3 y K sp = [Sr 2+ ][CO 3 ] [Sr 2+ ] = ( / ) = } 1 mark 92. [OH - ] = antilog(-2.00) = 0.0M Mg(OH) 2 Mg 2+ + OH - x 0.0 K sp = [Mg 2+ ][OH - ] 2 = (x) (0.0) 2 = M }1 1 / 2 mark [Mg 2+ ] = x = M ( 1 / 2 mark) 93. Mol CaF 2 = g (1 mol / 78.1 g) = Solubility = ( mol / 1.00L) = M }1 mark CaF 2(s) Ca 2+ (aq) + F - (aq) ( ) = K sp = [Ca 2+ ][F - ] 2 = ( )( ) 2 = }2 marks RAYCROFT 2 - Solubility Study Guide - Written - Page 9 of 11

10 9. Use the final unchanged mass (dish + BaF 2 ): Mass of BaF 2 = 72.8g 72.0g = 0.31g Solubility is [ 0.31g (1 mol / 17.3g) / 0.000L] = mol/L (1 1 / 2 marks) K sp = [Ba 2+ ][F - ] 2 = (0.0039)( ) 2 = }1 1 / 2 marks 9. K eq = [isobutene] / [n butane] ( 1 / 2 mark) = 3.0 / 2.0 = 1. ( 1 / 2 mark) 9. [Ca(NO 3 ) 2 ] = 0.00M (100.0mL / 00.0mL) = 0.120M [Ca 2+ ] = 0.120M [NO - 3 ] = 0.20M.. Mn(IO 3 ) 2(s) Mn 2+ (aq) + 2IO 3 - (aq) (1mark) c) [Mn 2+ ] = M [IO - 3 ] = M = M. Ag Ag + + Cl - s s [Ag + ][Cl - ] = s 2 = s = M [Ag + ] = M Ag 2 CO 3 2Ag + + CO 3 2s s [Ag + ] 2 [CO 3 ] = s = s = M [Ag + ] = M }1 mark }2 marks }2 marks Therefore [Ag + ] in Ag 2 CO 3 is higher than [Ag + ] in AgCl. RAYCROFT 2 - Solubility Study Guide - Written - Page 10 of 11

11 RAYCROFT 2 - Solubility Study Guide - Written - Page 11 of 11