CHEM1B CHAPTER 11 QUIZ

The normal temperature range of the liquid phase of pure water is 0℃ to 100℃. Which of the following
solutions will have the largest temperature range for the liquid state?

• 1 M aqueous ethanol solution

• 1 M aqueous potassium bromide solution

• 1 M aqueous acetic acid solution

• 1 M aqueous magnesium bromide solution

• 1 M aqueous magnesium sulfate

Tags

NGSS.HS-PS3-4

What physical property is used to separate the hydrocarbon components in petroleum (crude oil)?

• melting point

• density

• boiling point

• molar mass

• viscosity

Which of the following statements regarding the phase diagram of water and an aqueous solution is NOT
correct? Temperature is on the x-axis; pressure is on the y-axis.

• The boiling point of the solution is higher than that of the solvent by an amount indicated
  by the difference in temperature between points E and F.

• Point D corresponds to the triple point of the solvent.

• The solution boils at the temperature corresponding to point F

• The normal freezing point of the solution corresponds to point A.

• The freezing point of the solvent is higher than that of the solution.

Which statement below regarding vapor pressure is NOT correct?

• Vapor pressure is an intensive property

• The substance with the stronger intermolecular forces has the lower vapor pressure.

• Vapor pressure increases with increasing temperature.

• Pure water has a higher vapor pressure at a given temperature than seawater

• A nonvolatile solute increases the vapor pressure of the solvent.

Which of the following statements regarding solutions and the van ’t Hoff factor is NOT correct?

• Nonideal behavior can occur in solutions containing ions when the ions do not behave as
  independent particles in solution.

• Theoretical van ’t Hoff factors often predict colligative properties of solutions with
  concentrations of about 0.01 m or less.

• In dilute solutions, the experimental van ’t Hoff factor for a molecule is always greater
  than 1.

• As concentrations increase, the probability of ion pairing increases.

• The deviation from ideal behavior generally increases as the charge on dissolved ions
  increases.

A solution is prepared by mixing 50.00 g of methanol (CH3OH, 32.04 g/mol) with 50.00 g of ethanol
(CH3CH2OH, 46.07 g/mol). Use the following data to determine the vapor pressure of this solution at 20℃.

• 69 torr

• 57 torr

• 79 torr

• 72 torr

• 83 torr

Tags

NGSS.HS-PS3-4

The Henry’s law constant for oxygen dissolving in blood is 3.74x10^2 mol/L·atm at body temperature,
37℃. Calculate the molar concentration of oxygen in blood for an alpine climber where the atmospheric
pressure is 0.45 atm. The mole fraction of oxygen in air is 0.209.

• 7.8 x 10^3 M

• 3.5 x 10^3 M

• 2.3 x 10^2 M

• 1.3 x 10^2 M

• 0.11 M

The normal boiling point of bromine is 58.8℃, and its enthalpy of vaporization is 30.91 kJ/mol. What is the
approximate vapor pressure of bromine at 10.0℃?

• 0.998 atm

• 0.735 atm

• 0.853 atm

• 0.145 atm

• 6.89 atm

What is the boiling point elevation constant of ethanol if a solution prepared by dissolving 56.00 g of
glycerin (C3H8O3 , 92.11 g/mol) in 240.0 g of ethanol (C2H6O, 46.08 g/mol) has a boiling point change of
3.014℃? （Answer unit: ℃/m)

• 1.029

• 0.6080

• 1.190

• 0.8405

• 0.4398

What is the boiling point of a solution prepared by dissolving 157.0 g of urea (CH4N2O, 60.06 g/mol) in
750.0 g of water? (Kb= 0.512℃/m for water) （Answer unit: ℃)

• 98.22

• 101.00

• 99.00

• 101.78

• 100.26