Question 1

Which of the following best describes a colloid?

Accepted Answer

A homogeneous mixture with particles large enough to scatter light but not settle out.

Question 2

A solution is prepared by dissolving 5.00 g of NaCl in enough water to make 250.0 mL of solution. What is the molarity of the solution? (Molar mass of NaCl = 58.44 g/mol)

Accepted Answer

$$0.342\ \mathrm{M}$$

Question 3

Which of the following statements about the effect of temperature on solubility is correct?

Accepted Answer

The solubility of most solids in water increases as temperature increases.

Question 4

A 10.0 mL sample of 6.0 M HCl is diluted to a final volume of 60.0 mL. What is the final concentration?

Accepted Answer

$$1.0\ \mathrm{M}$$

Question 5

Which of the following best describes the direction of osmosis when a red blood cell is placed in a hypertonic solution?

Accepted Answer

Water moves out of the cell, causing it to shrink.

Question 6

Which of the following is a property of a strong acid?

Accepted Answer

It completely dissociates in water.

Question 7

Which of the following is the correct balanced equation for the neutralization of sulfuric acid ($$\mathrm{H_2SO_4}) $$with sodium hydroxide ($$\mathrm{NaOH}$$)?

Accepted Answer

$$\mathrm{H_2SO_4} + 2\ \mathrm{NaOH} \rightarrow \mathrm{Na_2SO_4} + 2\ \mathrm{H_2O}$$

Question 8

Which of the following is the correct equilibrium expression for the reaction: $$\mathrm{CH_3COOH} (aq) + \mathrm{H_2O} (l) \rightleftharpoons \mathrm{CH_3COO^-} (aq) + \mathrm{H_3O^+} (aq)$$?

Accepted Answer

$$K = \dfrac{[\mathrm{CH_3COO^-}][\mathrm{H_3O^+}]}{[\mathrm{CH_3COOH}]}$$

Question 9

A solution has $$[\mathrm{H_3O^+}] = 1.0 	imes 10$$^{-5}$$\ \mathrm{M}. $$What is its pH?

Accepted Answer

$$5.0$$

Question 10

Which of the following statements about Le Chatelier’s principle is correct?

Accepted Answer

If the concentration of a reactant is increased, the equilibrium will shift to produce more products.

Question 11

Which of the following is a correct application of the Henderson-Hasselbalch equation for a weak acid?

Accepted Answer

$$\mathrm{pH} = \mathrm{p}K_a + \log \left( \dfrac{[\mathrm{A^-}]}{[\mathrm{HA}]} \right)$$

Question 12

A pharmaceutical weak acid has a $$\mathrm{p}K_a of 4.5. If $$the pH of the surrounding solution is 7.5, which form (charged or uncharged) will predominate?

Accepted Answer

The charged (A$$^-) $$form will predominate.

Question 13

Which of the following is NOT a strong acid?

Accepted Answer

Acetic acid ($$\mathrm{CH_3COOH})$$

Question 14

Which of the following best describes active transport across a cell membrane?

Accepted Answer

Movement of molecules against their concentration gradient using energy.

Question 15

If a buffer solution contains $$[\mathrm{A^-}] = 0.10\ \mathrm{M}$$ and $$[\mathrm{HA}] = 1.0\ \mathrm{M}$$, and the $$\mathrm{p}K_a of $$the acid is 5.0, what is the pH of the solution?

Accepted Answer

$$4.0$$

Question 16

Which of the following best explains why the bicarbonate buffer system is important in human blood?

Accepted Answer

It helps maintain a stable pH despite metabolic and respiratory changes.

Question 17

Which of the following is the correct chemical equation for the dissociation of the weak electrolyte acetic acid ($$\mathrm{CH_3COOH}) in $$water?

Accepted Answer

$$\mathrm{CH_3COOH} (aq) + \mathrm{H_2O} (l) \rightleftharpoons \mathrm{CH_3COO^-} (aq) + \mathrm{H_3O^+} (aq)$$

Question 18

A solution is made by dissolving 0.50 g of KCl in enough water to make 1000 mL of solution. What is the concentration in parts per million (ppm)? (Assume density of water is $$1.00\ \mathrm{g/mL})$$

Accepted Answer

$$500\ \mathrm{ppm}$$

CHEM 102 Exam 4 Study Guide: Solution Chemistry and Acids/Bases (Ch. 8-9)

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