Q: A solution is prepared by dissolving 25 g of sugar in enough water to make 100 mL of solution. What is the mass/volume percent concentration of sugar in this solution?

$$\displaystyle \frac{25\ \text{g}}{100\ \text{mL}} \times 100\% = 25\%$$

Q: A nurse needs to prepare 250 mL of a 0.5 M NaCl solution from a stock solution of 2.0 M NaCl. What volume of the stock solution should be used?

$$\displaystyle V_1$ = \frac{C_2$ V_2$}{C_1$} = \frac{0.5\ \text{M} \times 250\ \text{mL}}{2.0\ \text{M}} = 62.5\ \text{mL}$$

Q: Which equation correctly expresses molarity?

$$\displaystyle M = \frac{\text{moles of solute}}{\text{liters of solution}}$$

Question 1

Which of the following best describes a solution?

Accepted Answer

A homogeneous mixture composed of a solute and a solvent.

Question 2

Which statement correctly explains the effect of temperature on the solubility of solids and gases in water?

Accepted Answer

Solids become more soluble at higher temperatures, while gases become less soluble.

Question 3

A solution is prepared by dissolving 25 g of sugar in enough water to make 100 mL of solution. What is the mass/volume percent concentration of sugar in this solution?

Accepted Answer

$$\displaystyle \frac{25\ 	ext{g}}{100\ 	ext{mL}} 	imes 100\% = 25\%$$

Question 4

Which of the following statements about colligative properties is TRUE?

Accepted Answer

They depend only on the number of solute particles, not their identity.

Question 5

A nurse needs to prepare 250 mL of a 0.5 M NaCl solution from a stock solution of 2.0 M NaCl. What volume of the stock solution should be used?

Accepted Answer

$$\displaystyle V_1$ = \frac{C_2$ V_2$}{C_1$} = \frac{0.5\ 	ext{M} 	imes 250\ 	ext{mL}}{2.0\ 	ext{M}} = 62.5\ 	ext{mL}$$

Question 6

Which of the following best describes a saturated solution?

Accepted Answer

A solution that contains the maximum amount of solute that can dissolve at a given temperature, with some undissolved solute present.

Question 7

Which equation correctly expresses molarity?

Accepted Answer

$$\displaystyle M = \frac{	ext{moles of solute}}{	ext{liters of solution}}$$

Question 8

Which of the following will increase the rate at which a solute dissolves in a solvent?

Accepted Answer

Increasing the temperature of the solution.

Question 9

A red blood cell is placed in a hypotonic solution. What is the most likely outcome?

Accepted Answer

The cell will swell and may burst (hemolysis).

Question 10

Which of the following best explains why sodium chloride ($$\displaystyle 	ext{NaCl}) $$increases the boiling point of water when dissolved in it?

Accepted Answer

The addition of solute particles causes boiling point elevation, a colligative property.

Question 11

Which of the following is the correct equation for calculating percent by mass?

Accepted Answer

$$\displaystyle \%\ (m/m) = \frac{	ext{mass of solute}}{	ext{mass of solution}} 	imes 100\%$$

Question 12

A solution is made by mixing 10 mL of ethanol with enough water to make 100 mL of solution. What is the percent by volume of ethanol?

Accepted Answer

$$\displaystyle \frac{10\ 	ext{mL}}{100\ 	ext{mL}} 	imes 100\% = 10\%$$

Question 13

Which of the following statements about osmosis is correct?

Accepted Answer

Solvent molecules move through a semipermeable membrane from a region of low solute concentration to high solute concentration.

Question 14

Which of the following best describes the phrase 'like dissolves like'?

Accepted Answer

Polar solutes dissolve in polar solvents, and nonpolar solutes dissolve in nonpolar solvents.

Question 15

How many particles are produced when one formula unit of calcium chloride ($$\displaystyle 	ext{CaCl}_2) $$dissolves in water?

Accepted Answer

Three particles: one $$\displaystyle 	ext{Ca}^{2+}$$ ion and two $$\displaystyle 	ext{Cl}^-$$ ions.

Question 16

A solution is labeled as 1.5 M NaOH. Which of the following is a correct conversion factor based on this information?

Accepted Answer

$$\displaystyle 1.5\ 	ext{mol NaOH} = 1\ 	ext{L solution}$$

Question 17

Which of the following statements about osmotic pressure is TRUE?

Accepted Answer

Osmotic pressure increases as the concentration difference across the membrane increases.

Question 18

Which equation is used to compare osmotic pressure using osmolality?

Accepted Answer

$$\displaystyle 	ext{Osm} = M 	imes i$$

Solutions, Concentration, and Colligative Properties – Guided Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard