Quimica analitica

July 19, 2009 [PROBLEM SET FROM R. CHANG TEST BANK]

Chapter Four.

Solution

Student: ____________________________________________________________

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60. What mass of K2CO3 is needed to prepare 200. mL of a solution having a potassium ion concentration of 0.150 M? A. B. C. D. E. 4.15 g 10.4 g 13.8 g 2.07 g 1.49 g

61. What mass of Na2SO4 is needed to prepare 350. mL of asolution having a sodium ion concentration of 0.125 M? A. B. C. D. E. 3.11 g 24.9 g 12.4 g 6.21 g 8.88 g

62. What mass of Li3PO4 is needed to prepare 500. mL of a solution having a lithium ion concentration of 0.175 M? A. B. C. D. E. 6.75 g 10.1 g 19.3 g 30.4 g 3.38 g

63. A 50.0 mL sample of 0.436 M NH4NO3 is diluted with water to a total volume of 250.0 mL. What is the ammonium nitrateconcentration in the resulting solution? A. B. C. D. E. 21.8 M 0.459 M 2.18 10-2 M 8.72 10-2 M 0.109 M

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July 19, 2009 [PROBLEM SET FROM R. CHANG TEST BANK] 64. A 20.00 mL sample of 0.1015 M nitric acid is introduced into a flask, and water is added until the volume of the solution reaches 250. mL. What is the concentration of nitric acid in the final solution? A. B.C. D. E. 1.27 M 8.12 10-3 M 0.406 M 3.25 10-2 M 5.08 10-4 M

65. A 3.682 g sample of KClO3 is dissolved in enough water to give 375. mL of solution. What is the chlorate ion concentration in this solution? A. B. C. D. E. 3.00 10-2 M 4.41 10-2 M 0.118 M 1.65 10-2 M 8.01 10-2 M

66. A 4.691 g sample of MgCl2 is dissolved in enough water to give 750. mL of solution. What is the magnesium ionconcentration in this solution? A. B. C. D. E. 3.70 10-2 M 1.05 10-2 M 6.57 10-2 M 4.93 10-2 M 0.131 M

67. A 0.9182 g sample of CaBr2 is dissolved in enough water to give 500. mL of solution. What is the calcium ion concentration in this solution? A. B. C. D. E. 9.19 2.30 2.72 4.59 1.25 10-3 M 10-3 M 10-3 M 10-3 M 10-3 M

68. 35.0 mL of 0.255 M nitric acid is added to 45.0 mL of 0.328 MMg(NO3)2. What is the concentration of nitrate ion in the final solution? A. B. C. D. E. 0.481 M 0.296 M 0.854 M 1.10 M 0.0295 M

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July 19, 2009 [PROBLEM SET FROM R. CHANG TEST BANK] 69. 17.5 mL of a 0.1050 M Na2CO3 solution is added to 46.0 mL of 0.1250 M NaCl. What is the concentration of sodium ion in the final solution? A. B. C. D. E. 0.205 M 0.119 M 0.539 M 0.148M 0.165 M

70. 25.0 mL of a 0.2450 M NH4Cl solution is added to 55.5 mL of 0.1655 M FeCl3. What is the concentration of chloride ion in the final solution? A. B. C. D. E. 0.607 M 0.418 M 1.35 M 0.190 M 0.276 M

71. When 38.0 mL of 0.1250 M H2SO4 is added to 100. mL of a solution of PbI2, a precipitate of PbSO4 forms. The PbSO4 is then filtered from the solution, dried, and weighed. If therecovered PbSO4 is found to have a mass of 0.0471 g, what was the concentration of iodide ions in the original solution? A. B. C. D. E. 3.10 1.55 6.20 3.11 1.55 10-4 M 10-4 M 10-3 M 10-3 M 10-3 M

72. When 50.0 mL of a 0.3000 M AgNO3 solution is added to 50.0 mL of a solution of MgCl2, an AgCl precipitate forms immediately. The precipitate is then filtered from the solution, dried, and weighed. Ifthe recovered AgCl is found to have a mass of 0.1183 g, what was the concentration of magnesium ions in the original MgCl2 solution? A. B. C. D. E. 0.300 M 8.25 10-3 M 1.65 10-2 M 2.06 10-5 M 4.13 10-3 M

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July 19, 2009 [PROBLEM SET FROM R. CHANG TEST BANK] 73. When 20.0 mL of a 0.250 M (NH4)2S solution is added to 150.0 mL of a solution of Cu(NO3)2, a CuSprecipitate forms. The precipitate is then filtered from the solution, dried, and weighed. If the recovered CuS is found to have a mass of 0.3491 g, what was the concentration of copper ions in the original Cu(NO3)2 solution? A. B. C. D. E. 3.65 1.22 3.33 4.87 2.43 10-3 M 10-2 M 10-2 M 10-2 M 10-2 M

74. 34.62 mL of 0.1510 M NaOH was needed to neutralize 50.0 mL of an H2SO4 solution. What is the...