Q: A solution is prepared by dissolving 15.5 g NaCl in water to make 1.50 L of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.44 g/mol)

$$\frac{15.5 \ \text{g}}{58.44 \ \text{g/mol}} = 0.2652 \ \text{mol}$$; \ M = \frac{0.2652 \ \text{mol}}{1.50 \ \text{L}} = 0.177 \ \text{M}$

Q: A saline solution contains 0.90 g NaCl in 100.0 mL of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.44 g/mol)

$$\frac{0.90 \ \text{g}}{58.44 \ \text{g/mol}} = 0.0154 \ \text{mol}$$; \ M = \frac{0.0154 \ \text{mol}}{0.100 \ \text{L}} = 0.154 \ \text{M}$

Q: Which equation is used to calculate mass percent of a solute in a solution?

$$\text{mass percent} = \frac{\text{mass solute}}{\text{mass solute} + \text{mass solvent}} \times 100\%$$

Question 1

Which of the following best explains why carbon dioxide was able to build up in solution at the bottom of Lake Nyos, leading to the 1986 tragedy?

Accepted Answer

The high pressure at the lake bottom increased CO2 solubility.

Question 2

Which of the following is NOT a colligative property of solutions?

Accepted Answer

Solubility of the solute

Question 3

A solution is prepared by dissolving 15.5 g NaCl in water to make 1.50 L of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.44 g/mol)

Accepted Answer

$$\frac{15.5 \ 	ext{g}}{58.44 \ 	ext{g/mol}} = 0.2652 \ 	ext{mol}$$; \ M = \frac{0.2652 \ 	ext{mol}}{1.50 \ 	ext{L}} = 0.177 \ 	ext{M}$

Question 4

Which statement correctly describes the effect of temperature on the solubility of gases in water?

Accepted Answer

Solubility of gases decreases as temperature increases.

Question 5

Which of the following solutions will conduct electricity?

Accepted Answer

A solution of sodium chloride (NaCl) in water

Question 6

Which equation is used to calculate the dilution of a solution?

Accepted Answer

$$M_1V_1 = M_2V_2$$

Question 7

A 1.50 M Na3PO4 solution is prepared. What are the molar concentrations of Na+ and PO43– ions in the solution?

Accepted Answer

Na+: 4.50 M, PO43–: 1.50 M

Question 8

Which of the following best describes a colloid?

Accepted Answer

A mixture with particles between 1 nm and 1000 nm that scatter light (Tyndall effect)

Question 9

Which of the following statements about 'like dissolves like' is correct?

Accepted Answer

Polar solvents dissolve polar solutes and ionic compounds.

Question 10

Which of the following is an example of a supersaturated solution?

Accepted Answer

A solution that contains more solute than it can theoretically hold at a given temperature.

Question 11

Which factor has the greatest effect on the solubility of gases in liquids?

Accepted Answer

Pressure

Question 12

A saline solution contains 0.90 g NaCl in 100.0 mL of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.44 g/mol)

Accepted Answer

$$\frac{0.90 \ 	ext{g}}{58.44 \ 	ext{g/mol}} = 0.0154 \ 	ext{mol}$$; \ M = \frac{0.0154 \ 	ext{mol}}{0.100 \ 	ext{L}} = 0.154 \ 	ext{M}$

Question 13

Which of the following best describes the process of osmosis?

Accepted Answer

The flow of solvent from a less concentrated solution to a more concentrated solution through a semipermeable membrane.

Question 14

Which equation is used to calculate mass percent of a solute in a solution?

Accepted Answer

$$	ext{mass percent} = \frac{	ext{mass solute}}{	ext{mass solute} + 	ext{mass solvent}} 	imes 100\%$$

Question 15

Which of the following would increase the rate at which a solid solute dissolves in water?

Accepted Answer

Stirring the solution

Question 16

A 0.75 M CaCl2 solution is prepared. What are the molar concentrations of Ca2+ and Cl– ions in the solution?

Accepted Answer

Ca2+: 0.75 M, Cl–: 1.50 M

Question 17

Which of the following is a real-world example of freezing point depression?

Accepted Answer

Adding salt to roads in winter to prevent ice formation

Question 18

Which of the following statements about persistent organic pollutants (POPs) is correct?

Accepted Answer

POPs are nonpolar and accumulate in fatty tissues, increasing concentration up the food chain.

Chapter 13: Solutions – Structure, Properties, and Calculations

Guida di studio - Domande di pratica

Study guide - Flashcard