Question 1

Which of the following best explains why the mixing of two gases is a spontaneous process?

Accepted Answer

Mixing increases the entropy of the system.

Question 2

A solution is prepared by dissolving 10.0 g of NaCl in 100.0 g of water. Which component is the solute and which is the solvent?

Accepted Answer

NaCl is the solute; water is the solvent.

Question 3

Which of the following substances is most likely to dissolve in water?

Accepted Answer

Glucose (C6H12O6)

Question 4

A supersaturated solution is best described as:

Accepted Answer

A solution that contains more solute than is normally possible at that temperature.

Question 5

Which of the following statements about Henry’s Law is correct?

Accepted Answer

The solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the solution.

Question 6

Calculate the molarity of a solution prepared by dissolving 5.00 g of NaCl (molar mass = 58.44 g/mol) in enough water to make 250.0 mL of solution.

Accepted Answer

$$0.342\ 	ext{M}$$

Question 7

Which of the following will increase the solubility of a gas in water?

Accepted Answer

Increasing the pressure of the gas above the solution.

Question 8

A solution is made by mixing 20.0 g of ethanol (C2H5OH, molar mass = 46.07 g/mol) with 80.0 g of water (molar mass = 18.02 g/mol). What is the mole fraction of ethanol in the solution?

Accepted Answer

$$0.106$$

Question 9

Which of the following best describes the effect of a nonvolatile solute on the vapor pressure of a solvent?

Accepted Answer

The vapor pressure of the solvent decreases.

Question 10

A 1.0 m solution of NaCl in water will have a greater boiling point elevation than a 1.0 m solution of glucose because:

Accepted Answer

NaCl dissociates into more particles in solution.

Question 11

Which equation correctly expresses Raoult’s Law for the vapor pressure of a solvent in a solution?

Accepted Answer

$$P_A = X_A P_A^\circ$$

Question 12

A solution is prepared by diluting 50.0 mL of 6.0 M HCl to a final volume of 300.0 mL. What is the final concentration?

Accepted Answer

$$1.0\ 	ext{M}$$

Question 13

Which of the following is a colligative property?

Accepted Answer

Freezing-point depression

Question 14

A 0.010 m aqueous solution of Al$$_2(SO$_4$$)$$_3 is $$prepared. Assuming complete dissociation, what is the van 't Hoff factor $$i$$ for this solution?

Accepted Answer

$$7$$

Question 15

Which of the following scenarios describes osmosis?

Accepted Answer

Water moves from an area of lower solute concentration to higher solute concentration through a semipermeable membrane.

Question 16

A solution is prepared by dissolving 2.05 g of polystyrene in enough toluene to make 0.100 L of solution. The osmotic pressure is found to be 1.21 kPa at 25 $$^\circC. $$What is the molar mass of the polystyrene? (Use $$\pi = MRT$$, $$R = 0.0821 L$$·atm·mol$$^{-1}$$·K$$^{-1}$$, $$T = 298 K$$, and $$1$$ atm $$= 101.3$$ kPa)

Accepted Answer

$$415,000\ 	ext{g/mol}$$

Question 17

Which of the following best explains why adding salt to ice causes the ice to melt at a lower temperature?

Accepted Answer

The salt lowers the freezing point of water by disrupting the equilibrium between solid and liquid phases.

Question 18

A patient receives an intravenous solution that is hypotonic relative to their blood plasma. What is the most likely effect on their red blood cells?

Accepted Answer

Water will enter the cells, causing them to swell and possibly burst (hemolysis).

Question 19

Which of the following is the correct formula for calculating the freezing-point depression of a solution?

Accepted Answer

$$\Delta T_f = i K_f m$$

Properties of Solutions – GOB Chemistry Study Notes

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Study guide - Flashcard