A chemist wants to determine the molar mass of a naturally occurring substance isolated from spearmint. She adds 4.531 g of this substance to 25.00 g of acetone (C3H6O; molar mass 58.08 g/mol). The vapor pressure of the solution is determined to be 0.2464 atm at 25°C. If the vapor pressure of pure acetone at this temperature is 0.2630 atm, what is the mole fraction of the solvent in this solution? Give your answer to four significant digits. Xsolvent 0.936882129

A chemist wants to determine the molar mass of a naturally occurring substance isolated from spearmint. She adds 4.531 g of this substance to 25.00 g of acetone (C3H6O; molar mass 58.08 g/mol). The vapor pressure of the solution is determined to be 0.2464 atm at 25°C. If the vapor pressure of pure acetone at this temperature is 0.2630 atm, what is the mole fraction of the solvent in this solution? Give your answer to four significant digits. Xsolvent 0.936882129

Chemistry & Chemical Reactivity

10th Edition

ISBN:9781337399074

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter15: Principles Of Chemical Reactivity: Equilibria

Section15.6: Disturbing A Chemical Equilibrium

Problem 2.1ACP: Freezing point depression is one means of determining the molar mass of a compound. The freezing...

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A 12.0-g sample of a nonelectrolyte is dissolved in 80.0 g of water. The solution freezes at -1.94 C. Calculate the molar mass of the substance.
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Consider two hypothetical pure substances, AB(s) and XY(s). When equal molar amounts of these substances are placed in separate 500-mL samples of water, they undergo the following reactions: AB(s)A+(aq)+B(aq)XY(s)XY(aq) a Which solution would you expect to have the lower boiling point? Why? b Would you expect the vapor pressures of the two solutions to be equal? If not, which one would you expect to have the higher vapor pressure? c Describe a procedure that would make the two solutions have the same boiling point. d If you took 250 mL of the AB(aq) solution prepared above, would it have the same boiling point as the original solution? Be sure to explain your answer. e The container of XY(aq) is left out on the bench top for several days, which allows some of the water to evaporate from the solution. How would the melting point of this solution compare to the melting point of the original solution?
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