1. | Colligative properties depend on .. |
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2. | At a given temperature, you have a mixture of benzene (vapor pressure of pure benzene = 745 torr) and toluene(vapor pressure of pure toluene = 290 torr). The mole fraction of benzene in solution is 0.59. Assuming ideal behavior, calculate the mole fraction of toluene in the vapor above the solution. |
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3. | When a 20 g sample of an unknown compound is dissolved in 500g of benzene, the freeezing point of the resulting solution is 3.77^{o}C. The freezing point of pure benzene is 5.48^{o}C and the K value for benzene is 5.12. Calcualte the molar mass of the unknown |
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4. | Raoult's law relates the vapor pressure of the solvent above the soltion to its mole fraction in the solutio. Which of the following is an accurate statement? |
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5. | What is the molality of a solution of 50 g of CH3CH2CH2OH in 152 mL water, if the density of water is 1 g/mL? |
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6. | 150g of NaCl dissolves in 1 kg of water at 25^{o}C. the vapor pressure of pure water at this temperature is 23.8 torr. Determine the vapore pressure of the solution. |
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7. | A 2.300 molal solution of KCl is prepared. How many grams of KCl are present in a sample containing 5.0 kg of water? |
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8. | A solution if prepared from 31.4g of a nonvolatile, nondissociating solute and 85g of water. The vapor pressure of the solution at 60^{o}C is 142 torr. The vapor pressure of water at 60^{o}C is 150 torr. What is the molar mass of the solute? |
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9. | The solubility of oxygen gas in water is 0.590 g/L at a pressure of 15 atm. What is the Henry's law constant for oxygen gas in units of L-atm/mol? |
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10. | Calculate the molarity of a solution contians KCl and water whose osmotic pressure at 21^{o}C is 100 torr. |
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11. | The Tyndall effect.. |
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12. | What increases when 2 pure substances are mixed to form a solution? |
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