Exam 11: Solutions: Properties and Behavior

The molal concentration of ions in seawater is 1.17 m, and the molar concentration is 1.15 M. What is the minimum pressure that must be applied to produce pure water from seawater through reverse osmosis at 25C?

At 25C, the vapor pressure of pure water is 25.756 mm Hg. What is the vapor pressure of water in a 0.500 m solution of sodium chloride?

Which of the following will have the largest cation-anion attraction?

Coulomb's law states that the energy of attraction between ions depends ________

Indicate which aqueous solution has the slowest evaporation rate.

Write out the five steps of the Born-Haber cycle for formation of solid sodium chloride from its elements. Label what energy each step corresponds to. Also, note which steps are exo- or endothermic.

In the following Born-Haber cycle for the formation of sodium chloride from its elements, which step (A-E) corresponds to a molar heat of sublimation for one of the reactants?

Which of the following compounds has the lowest melting point?

In the following Born-Haber cycle for the formation of sodium chloride from its elements, which step (A-E) corresponds to the ionization energy of one of the reactants?

The term colligative refers to properties that ________

Which statement A-D about ionic solids is not correct?

Suppose 100.0 mL of a 2.50 mM NaCl solution were mixed with 100.0 mL of a 3.40 mM MgCl₂ solution at 25C. Assuming the volumes are additive and using the ideal van 't Hoff factors, what would be the osmotic pressure of the resulting solution?

Identify the following statement as true or false and choose the correct explanation. "For solutions with the same molarity at the same temperature, the pressure needed for reverse osmosis of a sodium chloride solution will always be less than the pressure needed for a calcium chloride solution."

In the process of dialysis, a special semipermeable membrane allows both small molecules and water to pass through, but not large protein molecules. These membranes are used to separate these small molecules and ions from much larger proteins. If a mixture of proteins and small molecules were separated from pure water by a dialysis membrane as shown in the figure, which way would the molecules flow?

What mass of a 1.23 m sodium carbonate (105.99 g/mol) solution will contain 0.23 mol of solute?

The freezing point of a 0.060 m solution of magnesium sulfate (MgSO₄) is 0.18C. What is the value of the van 't Hoff factor for this nonideal solution? K_f for water is 1.86C/m.

A petroleum company separates benzene (78 g/mol) and n-octane (114 g/mol) by distillation. In one run, the starting solution was 15% benzene and 85% n-octane by mass at 25C. In the liquid, the mole ratio of benzene to n-octane was ________, and in the vapor it was ________. The vapor pressures for benzene and n-octane at this temperature are 11 torr and 95 torr, respectively.

Ion interaction energies are determined by Coulomb's law: Determine the energy of potassium chloride if the radius of the potassium ion is 133 pm and that of the chloride ion is 181 pm.

Which of the following solutions, assuming equal volumes and a nonvolatile solute, would have the highest boiling point? Provide rationale for your choice.

Indicate which aqueous solution has the lowest vapor pressure.