Chapter 16 Practice Test

Question 1

All of the following are considered binary strong acids except:

Answer 1

Chloric acid

Question 2

Which of the following conjugate acid / base pairs is incorrect?

Answer 2

H + / OH −

Question 3

Which of the following can be considered a concentrated solution of a weak acid?

Answer 3

1 M HF

Question 4

What is the pH of a solution with a [H3O+ ] of 1.9 × 10^−5 M?

Answer 4

4.72

Question 5

Which of the following is the most acidic?

Answer 5

pH = 4

Question 6

What is the Kw for pure water at 25°C?

Answer 6

1 × 10^−14

Question 7

What is the pH of a solution of hydrochloric acid with a concentration of 1 × 10^−4 M?

Answer 7

4

Question 8

Suppose hydrobromic acid is dissolved in water to form a 0.03 M solution. What is the pH and the pOH?

Answer 8

pH = 1.52, pOH = 12.48

Question 9

What is the pH of a solution of orange juice whose hydrogen ion concentration is 2.9 × 10^−4 M?

Answer 9

3.53

Question 10

Which of the following is the formula for pKa?

Answer 10

− log 10 (Ka )

Question 11

Hydrofluoric acid is a weak acid with an equilibrium constant (at 25°C) of Ka = 7.2 × 10^−4. What is the pH of a 1.00 M solution of this acid?

Answer 11

1.57

Question 12

A 2.5 M solution of a monoprotic acid has a pH of 2.50 at 25°C. What is the equilibrium constant for this acid? Is it a strong or weak acid?

Answer 12

4.1×10^−6, weak

Question 13

What is the pH of a 10.0 M solution of ammonia (NH3 )? Kb = 1.8 × 10^−5.

Answer 13

12.11

Question 14

Lactic acid is what makes sour milk taste sour. It is also a by-product of physical exertion and can cause sore muscles. It is a weak monoprotic acid with the formula CH3CHOHCO2H. In water, it partially dissociates, Ka = 1.4 × 10^−4, to form hydronium ions and the conjugate base CH3CHOHCO2−. Determine Kb for this base

Answer 14

7.1 × 10^−11

Question 15

Pyridine, a component of coal tar, is a base. A 1.0 × 10^−2 M solution of this base has a pH of 8.6 at 25°C. What is the equilibrium constant for this base? Is it a strong or weak base?

Answer 15

1.6 × 10^−9, weak

Question 16

Which of these species can act as a Lewis acid?

Answer 16

NO2

Question 17

Silver chloride, AgCl, is only slightly soluble in water. The solubility can be increased by adding which of the following?

Answer 17

NH3

Question 18

Which one of the following is unlikely to act as a Lewis base?

Answer 18

Cr3+

Question 19

Which of the following acids is the strongest?

Answer 19

HClO4

Question 20

Why is HI a stronger acid than HF?

Answer 20

The bond strength of HF is greater than the bond strength of HI.

Question 21

Which of the following acids is the strongest?

Answer 21

HI

Question 22

Examine the following two equilibria.

H2CO3(aq) + H2O(l) <==> H3O+(aq) + HCO3-(aq)
HCO3-(aq) + H2O(l) <==> H3O+(aq) + CO32-(aq)

Which of the species (other than water) is amphoteric?

Answer 22

HCO3-

Question 23

Carbhonic acid (a diprotic acid) dissociates in water according tot he following equations:

H2CO3(aq) + H2O(l) <==> H3O+(aq) + HCO3-(aq)
HCO3-(aq) + H2O(l) <==> H3O+(aq) + CO32-(aq)

The acid dissociation constants are:
Ka1 = 4.310^-7 and Ka2 = 5.610^-11.
What is [H3O+] due to the second dissociation in a carbonic acid solution?

Answer 23

5.6*10^-11

Question 24

Which of the following reactions would produce a salt that is acidic in solution?

Answer 24

H2SO4 + NH3

Question 25

Which of the following is an example of a relatively weak acid reacting with a strong base?

Answer 25

Benzoic acid + sodium hydroxide