/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 59 Consider two solutions, one form... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Consider two solutions, one formed by adding \(10 \mathrm{~g}\) of glucose \(\left(\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}\right)\) to \(1 \mathrm{~L}\) of water and the other formed by adding \(10 \mathrm{~g}\) of sucrose \(\left(\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}\right)\) to \(1 \mathrm{~L}\) of water. Are the vapor pressures over the two solutions the same? Why or why not?

Short Answer

Expert verified
The vapor pressures over the two solutions are not the same. The glucose solution has a higher molality (0.0556 mol/kg) than the sucrose solution (0.0292 mol/kg), which leads to a lower mole fraction of the solvent (water) in the glucose solution. According to Raoult's law, this results in a lower vapor pressure over the glucose solution compared to the sucrose solution.

Step by step solution

01

Compute the molality of solutions

First, compute the molality of each solution by dividing the ratio of the mass of the solute to the mass of the solvent. Remember that we will need the molecular weights of glucose (C6H12O6) and sucrose (C12H22O11) to compute the number of moles. The molecular weights are approximately 180g/mol for glucose and 342g/mol for sucrose, and we are using 1000g of water (solvent) for each case. For glucose solution: Molality = (10g) / (180g/mol) / (1000g) = 0.0556 mol/kg For sucrose solution: Molality = (10g) / (342g/mol) / (1000g) = 0.0292 mol/kg
02

Compare the molalities and vapor pressure

We can see that the molality of the glucose solution (0.0556 mol/kg) is greater than the molality of the sucrose solution (0.0292 mol/kg). According to the Raoult's law, the vapor pressure of a solution is directly proportional to the mole fraction of the solvent, and as the molality of the glucose solution is higher, the mole fraction of the solvent (water) would be lower, resulting in a lower vapor pressure over the glucose solution compared to the sucrose solution. Therefore, the vapor pressures over the two solutions are not the same. The vapor pressure over glucose solution will be lower than the vapor pressure over sucrose solution due to the higher molality of glucose solution, which causes a lower mole fraction of the solvent and thus, a lower vapor pressure.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Calculate the molarity of the following aqueous solutions: (a) \(0.540 \mathrm{~g} \mathrm{Mg}\left(\mathrm{NO}_{3}\right)_{2}\) in \(250.0 \mathrm{~mL}\) of solution, (b) \(22.4 \mathrm{~g} \mathrm{LiClO}_{4} \cdot 3 \mathrm{H}_{2} \mathrm{O}\) in \(125 \mathrm{~mL}\) of solution, (c) \(25.0 \mathrm{~mL}\) of \(3.50 \mathrm{M} \mathrm{HNO}_{3}\) diluted to \(0.250 \mathrm{~L}\).

(a) Would you expect stearic acid, \(\mathrm{CH}_{3}\left(\mathrm{CH}_{2}\right)_{16} \mathrm{COOH}\), to be more soluble in water or in carbon tetrachloride? Explain. (b) Which would you expect to be more soluble in water, cyclohexane or dioxane? Explain.

The maximum allowable concentration of lead in drinking water is \(9.0\) ppb. (a) Calculate the molarity of lead in a \(9.0\) -ppb solution. What assumption did you have to make in your calculation? (b) How many grams of lead are in a swimming pool containing \(9.0\) ppb lead in \(60 \mathrm{~m}^{3}\) of water?

A solution is made containing \(25.5 \mathrm{~g}\) phenol \(\left(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{OH}\right)\) in \(425 \mathrm{~g}\) ethanol \(\left(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}\right)\). Calculate (a) the mole fraction of phenol, (b) the mass percent of phenol, (c) the molality of phenol.

(a) Why is there no colloid in which both the dispersed substance and the dispersing substance are gases? (b) Michael Faraday first prepared ruby-red colloids of gold particles in water that were stable for indefinite times. \(\infty 00\) (Section 12.6) To the unaided eye these brightly colored colloids are not distinguishable from solutions. How could you determine whether a given colored preparation is a solution or colloid?

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.