Concept explainers
The following plot shows the vapor pressure of various solutions of components A and B at some temperature.
Which of the following statements is false concerning solutions of A and B?
a. The solutions exhibit negative deviations from Raoult’s law.
b. ∆Hso1n for the solutions should be exothermic.
c. The intermolecular forces are stronger in solution than in either pure A or pure B.
d. Pure liquid B is more volatile than pure liquid A.
e. The solution with XB = 0.6 will have a lower boiling point than either pure A or pure B.
Trending nowThis is a popular solution!
Chapter 11 Solutions
Student Solutions Manual for Zumdahl/Zumdahl/DeCoste?s Chemistry, 10th Edition
Additional Science Textbook Solutions
MARINE BIOLOGY
Organic Chemistry (8th Edition)
Principles of Anatomy and Physiology
Chemistry: Structure and Properties (2nd Edition)
General, Organic, and Biological Chemistry - 4th edition
- Freezing point depression is one means of determining the molar mass of a compound. The freezing point depression constant of benzene is 5.12 C/m. a. When a 0.503 g sample of the white crystalline dimer is dissolved in 10.0 g benzene, the freezing point of benzene is decreased by 0542 C. Verify that the molar mass of the dimer is 475 g/mol when determined by freezing point depression. Assume no dissociation of the dimer occurs. b. The correct molar mass of the dimer is 487 g/mol. Explain why the dissociation equilibrium causes the freezing point depression calculation to yield a lower molar mass for the dimer.arrow_forwardA 1.00 mol/kg aqueous sulfuric acid solution, H2SO4,freezes at 4.04 C. Calculate i, the vant Hoff factor,for sulfuric acid in this solution.arrow_forwardWhat would be the freezing point of a solution formed by adding 1.0 mole of glucose (a molecular compound) to the following amounts of water? a. 250 g (0.25 kg) b. 500 g (0.500 kg) c. 1000 g (1.000 kg) d. 2000 g (2.000 kg)arrow_forward
- The vapor pressures of several solutions of water-propanol (CH3CH2CH2OH) were determined at various compositions, with the following data collected at 45C: H2O Vapor pressure(torr) 0 74.0 0.15 77.3 0.37 80.2 0.54 81.6 0.69 80.6 0.83 78.2 1.00 71.9 a. Are solutions of water and propanol ideal? Explain. b. Predict the sign of Hsoln for water-propanol solutions. c. Are the interactive forces between propanol and water molecules weaker than, stronger than, or equal to the interactive forces between the pure substances? Explain. d. Which of the solutions in the data would have the lowest normal boiling point?arrow_forwardThe vapor pressure of methanol, CH3OH, is 94 torr at 20 C. The vapor pressure of ethanol, C2H5OH, is 44 torr at the same temperature. (a) Calculate the mole fraction of methanol and of ethanol in a solution of 50.0 g of methanol and 50.0 g of ethanol. (b) Ethanol and methanol form a solution that behaves like an ideal solution. Calculate the vapor pressure of methanol and of ethanol above the solution at 20 C.arrow_forwardWater at 25 C has a density of 0.997 g/cm3. Calculate the molality and molarity of pure water at this temperature.arrow_forward
- (a) Which aqueous solution is expected to have the higher boiling point: 0.10 m Na2SO4 or 0.15 m sugar? (b) For which aqueous solution is the vapor pressure of water higher: 0.30 m NH4NO3 or 0.15 m Na2SO4?arrow_forwardSodium chloride (NaCl) is commonly used to melt ice on roads during the winter. Calcium chloride (CaCl2) is sometimes used for this purpose too. Let us compare the effectiveness of equal masses of these two compounds in lowering the freezing point of water, by calculating the freezing point depression of solutions containing 200. g of each salt in 1.00 kg of water. (An advantage of CaCl2 is that it acts more quickly because it is hygroscopic, that is. it absorbs moisture from the air to give a solution and begin the process. A disadvantage is that this compound is more costly.)arrow_forwardThe organic salt [(C4H9)4N][ClO4] consists of the ions (C4H9)4N+ and ClO4. The salt dissolves in chloroform. What mass (in grams) of the salt must have been dissolved if the boiling point of a solution of the salt in 25.0 g chloroform is 63.20 C? The normal boiling point of chloroform is 61.70 C and Kb = 3.63 C kg mol1. Assume that the salt dissociates completely into its ions in solution.arrow_forward
- a. Use the following data to calculate the enthalpy of hydration for calcium chloride and calcium iodide. Lattice Energy Hsoln CaCl2(s) 2247kj/mol 46kj/mol Cal2(s) 2059kj/mol 104kj/mol b. Based on your answers to part a, which ion, Cl or I, is more strongly attracted to water?arrow_forwardCalculate the molality of a solution made by dissolving 115.0 g ethylene glycol, HOCH2CH2OH, in 500. mL water. The density of water at this temperature is 0.978 g/mL. Calculate the molarity of the solution.arrow_forwardThe freezing point of 0.109 m aqueous formic acid is 0.210C. Formic acid, HCHO2, is partially dissociated according to the equation HCHO2(aq)H+(aq)+CHO2(aq) Calculate the percentage of HCHO2 molecules that are dissociated, assuming the equation for the freezing-point depression holds for the total concentration of molecules and ions in the solution.arrow_forward
- Chemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningGeneral Chemistry - Standalone book (MindTap Cour...ChemistryISBN:9781305580343Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; DarrellPublisher:Cengage LearningChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage Learning
- Chemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage LearningChemistry by OpenStax (2015-05-04)ChemistryISBN:9781938168390Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark BlaserPublisher:OpenStax