These sets of problems are about the concentrations and dilution of solutions from one concentration to another concentration.
Concentration Problems
| 1. | What is the molarity of a 18.0 mL solution if it contains: (a) 5.34 g of Zn(NO3)2, (b) 7.58 g of CaC2O4.H2O, (c) 4.39 g of H3BO3? (mol. wt.: Zn(NO3)2=189.3898, CaC2O4.H2O=146.1148, H3BO3=61.8319) |
| Answer: (a) 1.6 M, (b) 2.9 M, (c) 3.9 M |
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| 2. | Determine the weight in grams of the solute contained in a given volume and a given concentration of the following solutions: (a) 5.0 L of 5.76 M CuSO4 solution, (b) 12.0 mL of 0.83 M Mg(OH)2 solution, (c) 24.0 mL of 2.3 M CuSCN solution. (mol. wt.: CuSO4=159.6036, Mg(OH)2=58.3196, CuSCN=121.6237) |
| Answer: (a) 4596.6 g, (b) 0.6 g, (c) 6.7 g |
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| 3. | Calculate the weight of the solute required in order to prepare the following solutions: (a) 12.0 mL of 3.36 M Zn(NO3)2.6H2O solution, (b) 1.0 L of 1.35 M NaIO3 solution, (c) 6.0 L of 2.78 M NaCl solution. (mol. wt.: Zn(NO3)2.6H2O=297.481, NaIO3=197.89247, NaCl=58.44277) |
| Answer: (a) 12 g, (b) 267.2 g, (c) 974.8 g |
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| 4. | What is the molarity (M) of the following solutions: (a) 33% (w/w) sodium hydroxide solution with a density of 1.36 g/mL, (b) 40% (w/w) hydrobromic acid solution with a density of 1.38 g/mL. (mol. wt.: NaOH=39.99707, HBr=80.9119) |
| Answer: (a) 11.22 M, (b) 6.82 M |
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| 5. | Determine the weight in grams of the solute contained in the following solutions: (a) 10.0 mL of 0.58 M K2S2O5 solution, (b) 2.0 L of 1.78 M CaF2 solution, (c) 5.0 L of 0.48 M NaOH solution. (mol. wt.: K2S2O5=222.3136, CaF2=78.0768, NaOH=39.99707) |
| Answer: (a) 1.3 g, (b) 278 g, (c) 96 g |
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| 6. | Calculate the resulting molarity (M) of CH3COO-1 from the mixture of 18.00 mL of 4.79 M NaCH3COO solution and 21.00 mL of 3.11 M Ba(CH3COO)2 solution, assuming their volumes are additive. |
| Answer: 5.56 M |
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| 7. | Determine the weight in grams of the solute contained in the following solutions: (a) 10.0 mL of 0.92 M KClO3 solution, (b) 2.0 L of 1.38 M KSCN solution, (c) 4.0 L of 0.32 M ZnBr2 solution. (mol. wt.: KClO3=122.5495, KSCN=97.176, ZnBr2=225.188) |
| Answer: (a) 1.1 g, (b) 268.2 g, (c) 288.2 g |
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| 8. | Calculate the final molarity (M) of a mixed solution of 23.0 mL of 4.29 M CdC2O4.3H2O solution and 16.0 mL of 1.8 M CdC2O4.3H2O solution, assuming their volumes are additive. |
| Answer: 3.3 M |
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| 9. | Determine the weight in grams of the solute contained in a given volume and a given concentration of the following solutions: (a) 5.0 L of 0.13 M Ca(NO3)2.4H2O solution, (b) 14.0 mL of 5.73 M Na2CO3.H2O solution, (c) 22.0 mL of 5.89 M Na4P2O7 solution. (mol. wt.: Ca(NO3)2.4H2O=236.1506, Na2CO3.H2O=124.00394, Na4P2O7=265.9024) |
| Answer: (a) 153.5 g, (b) 9.9 g, (c) 34.5 g |
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| 10. | Calculate the resulting molarity (M) of C2O4-2 from the mixture of 6.00 mL of 1.9 M K2C2O4 solution and 9.00 mL of 4.78 M BaC2O4 solution, assuming their volumes are additive. |
| Answer: 3.6 M |
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Dilution Problems
| 1. | What is the volume of the diluted solution of 25.0 mL of 4.77 M Mg(NO3)2.6H2O if its final concentration is 0.41 M Mg(NO3)2.6H2O? |
| Answer: 290.9 mL |
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| 2. | What is the volume of the diluted solution of 17.0 mL of 3.91 M AgNO3 if its final concentration is 1.4 M AgNO3? |
| Answer: 47.5 mL |
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| 3. | 14 mL of an unknown concentration of Co(NO3)2.6H2O solution was diluted to 21.9 mL to make a concentration of 1.46 M Co(NO3)2.6H2O. Determine the initial concentration of the diluted solution. |
| Answer: 2.28 M |
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| 4. | 36.3 mL of 2.62 M K2CrO4 solution was prepared from an unknown volume of 4.32 M K2CrO4 solution. What was the initial volume of the solution? |
| Answer: 22.0 mL |
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| 5. | What is the volume of the diluted solution of 18.0 mL of 1.56 M NaClO3 if its final concentration is 1.44 M NaClO3? |
| Answer: 19.5 mL |
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| 6. | What is the volume of the diluted solution of 10.0 mL of 2.27 M KIO3 if its final concentration is 2.07 M KIO3? |
| Answer: 11 mL |
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| 7. | If 7.0 mL of 3.5 M NaHCO3 solution is diluted to 35.0 mL, calculate the new molarity of the solution. |
| Answer: 0.7 M |
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| 8. | 18.9 mL of 2.34 M KI solution was prepared from an unknown volume of 4.03 M KI solution. What was the initial volume of the solution? |
| Answer: 11.0 mL |
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| 9. | 5 mL of an unknown concentration of K2SO4 solution was diluted to 19.4 mL to make a concentration of 0.7 M K2SO4. Determine the initial concentration of the diluted solution. |
| Answer: 2.72 M |
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| 10. | 327 mL of 0.1 M NaNO2 solution was prepared from an unknown volume of 5.45 M NaNO2 solution. What was the initial volume of the solution? |
| Answer: 6.0 mL |
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