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

$$M = \frac{1.00\ \text{mol}}{1.00\ \text{L}} = 1.00\ \text{M}$$

$$m = \frac{0.25}{0.50} = 0.50\ \text{m}$$

$$\text{PPM} = \frac{\text{Amount of Solute}}{\text{Amount of Solution}} \times 10^6$

Question 1

Which of the following best describes a solution?

Accepted Answer

A homogeneous mixture of two or more substances with uniform composition.

Question 2

What is the correct formula for calculating molarity (M)?

Accepted Answer

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

Question 3

A solution is prepared by dissolving 58.44 g of NaCl in enough water to make 1.00 L of solution. What is the molarity of the solution?

Accepted Answer

$$M = \frac{1.00\ 	ext{mol}}{1.00\ 	ext{L}} = 1.00\ 	ext{M}$$

Question 4

Which intermolecular force is primarily responsible for the solubility of NaCl in water?

Accepted Answer

Ion-dipole interactions

Question 5

What happens to the water in your cells when you drink seawater?

Accepted Answer

Water flows out of your cells to equalize salt concentration, causing dehydration.

Question 6

Which of the following is NOT a common type of solution?

Accepted Answer

Liquid solute in gas solvent

Question 7

Which concentration unit is defined as moles of solute per kilogram of solvent?

Accepted Answer

Molality (m)

Question 8

A solution contains 0.25 mol of solute in 0.50 kg of solvent. What is the molality?

Accepted Answer

$$m = \frac{0.25}{0.50} = 0.50\ 	ext{m}$$

Question 9

Which equation correctly expresses parts per million (ppm) for a solution?

Accepted Answer

$$	ext{PPM} = \frac{	ext{Amount of Solute}}{	ext{Amount of Solution}} 	imes 10^6$

Question 10

Which of the following statements about entropy and mixing is correct?

Accepted Answer

Mixing increases entropy, which is the dispersal of energy throughout the system.

Question 11

Which scenario will most likely result in an exothermic solution formation?

Accepted Answer

Solute-solvent interactions are stronger than solute-solute and solvent-solvent interactions.

Question 12

Which of the following best explains why oil does not dissolve in water?

Accepted Answer

Oil is nonpolar and water is polar, so their intermolecular forces are not compatible.

Question 13

A solution is saturated when:

Accepted Answer

No more solute can be dissolved at a given temperature.

Question 14

Which of the following is the correct expression for mole fraction ($$\chi) of a $$solute?

Accepted Answer

$$\chi_{	ext{solute}} = \frac{n_{	ext{solute}}}{n_{	ext{solute}} + n_{	ext{solvent}}}$$

Question 15

Which intermolecular force is strongest in the hydration of Mg$$^{2+}$$ ions in water?

Accepted Answer

Ion-dipole interactions

Question 16

If the enthalpy of hydration for Li$$^+ is$$ $$-515 kJ/$$mol and for Cs$$^+ is$$ $$-263 kJ/$$mol, which ion is more strongly hydrated?

Accepted Answer

Li$$^+$$, because it has a smaller radius and a more negative enthalpy of hydration.

Question 17

Which of the following is a real-world example of a supersaturated solution?

Accepted Answer

A carbonated beverage that releases gas when shaken.

Question 18

Which equation represents the heat of solution for an ionic compound in water?

Accepted Answer

$$\Delta H_{	ext{solution}} = -\Delta H_{	ext{lattice energy}} + \Delta H_{	ext{hydration}}$$

Question 19

Which of the following best describes the process of osmosis?

Accepted Answer

The flow of solvent from low concentration to high concentration through a semipermeable membrane.

Solutions and Their Properties: Structure, Formation, and Concentration

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