Exam 11: Solutions: Properties and Behavior

Which of the following solutions, assuming equal volumes and a nonvolatile solute, would have the lowest freezing point?

Which of the following ionic compounds would you predict to have the highest solubility in water?

Indicate which aqueous solution has the lowest vapor pressure.

A physiological saline solution is 0.92% NaCl by mass. What is the osmotic pressure of such a solution at a body temperature of 37C?

Predict the relationship between the lattice energies (U) of KNO₃ and NaBr.

Define the terms enthalpy of solution, enthalpy of hydration, and lattice energy.

Which solution will have the lowest osmotic pressure when measured against pure water?

Which of the following will have the largest lattice energy?

You like boiled eggs for breakfast, but they take too long to cook, and you are always late to your early morning class. Lucky you! You have learned that adding table salt, NaCl (58.4 g/mol, 2.16 g/cm³), to water (K_b  0.52C/m) increases the temperature at which it boils. You figure that you can cook eggs faster at a higher temperature in boiling salty water! What increase in the boiling point do you expect if you add 1 tablespoon (1 tbsp  14.8 cm³) of salt to one 8-oz cup of water (237 mL)?

A 75 mg sample of a natural product isolated from alfalfa hay was dissolved in water to make 100.0 mL of solution. The solution did not conduct electricity and had an osmotic pressure of 0.246 atm at 27C. What is the molar mass of this compound?

A bottle is half-filled with a mixture of 25% liquid heptane and 75% liquid octane (mole fractions) at 25C. What is the mole ratio of heptane to octane in the space above the liquid compared to in the liquid? The vapor pressures are 31 torr for pure heptane and 11 torr for pure octane.

Which statement about the vapor pressure of a liquid is not correct?

Which arrangement below orders the cations from smallest to largest hydration energy? Smallest to largest means least negative hydration energy to most negative hydration energy.

A saline solution is administered intravenously to patients who cannot take fluid orally and are in danger of dehydration. The osmotic pressure of this solution must match that of blood to prevent hemolysis or crenation of blood cells. What mass of sodium chloride (58.44 g/mol) is needed to produce 100.0 mL of saline solution with an osmotic pressure of 7.83 atm at a body temperature of 37C?

What is the molarity of a 0.923 m NaF (41.99 g/mol) solution prepared using 234 g of water? The density of the solution is 1.13 g/mL.

Eugenol is a nonelectrolyte that contributes to the flavor of spices such as clove, nutmeg, cinnamon, and basil. A 328 mg sample of eugenol was dissolved in 10.0 g of chloroform (K_b  3.63C/m), increasing the boiling point of the chloroform by 0.726C. What is the molar mass of eugenol?

A 376 mg sample of a nonelectrolyte compound isolated from throat lozenges was dissolved in water to produce 10.0 mL of a solution at 25C. The osmotic pressure of this solution was measured and found to be 4.89 atm. What is the molar mass of this compound?

Which of the following ranks the compounds from lowest to highest lattice energy?

Which of the following is needed to calculate the lattice energy of an ionic compound?

Calculate the minimum pressure that must be applied to achieve reverse osmosis of 0.313 M Ca(NO₃)₂ at 35C.