Deck 17: Acids and Bases

Question 1

Which of the following acids will have the strongest conjugate base?

A) HCl
B) HClO₄
C) HNO₃
D) HCN
E) HI

Answer 1

HCN

Question 2

Which of the following is not a conjugate acid-base pair?

A) NH₄⁺/NH₃
B) H₃O⁺/OH⁻
C) H₂SO₃/HSO₃⁻
D) C₂H₃O₂⁻/HC₂H₃O₂
E) All of the above are conjugate acid-base pairs.

Answer 2

H₃O⁺/OH⁻

Question 3

What is the concentration of hydroxide ions in pure water at 30.0^∘C,if K_w at this temperature is 1.47 × 10^-14?

A) 1.00 × 10^-7 M
B) 1.30 × 10^-7 M
C) 1.47 × 10^-7 M
D) 8.93 × 10^-8 M
E) 1.21 × 10^-7 M

Answer 3

1.21 × 10^-7 M

Question 4

Which of the following solutions would have the highest pH? Assume that they are all 0.10 M in acid at 25^∘C.The acid is followed by its K_a value.

A) HF, 3.5 × 10^-4
B) HCN, 4.9 × 10^-10
C) HNO₂, 4.6 × 10^-4
D) HCHO₂, 1.8 × 10^-4
E) HClO₂, 1.1 × 10^-2

Question 5

What is the conjugate base of H₂PO₄⁻ ?

A) HPO₄^2-
B) PO₄^3-
C) H₃PO₄
D) H₃O⁺
E) OH⁻

Question 6

Identify the weak diprotic acid.

A) HNO₃
B) H₃PO₄
C) H₂SO₃
D) HClO₄
E) H₂SO₄

Question 7

An aqueous solution of ammonia is found to be basic.This observation can be explained by the net ionic equation

A) NO₃^-(aq) + H₂O(l) → HNO₃(aq) + OH^-(aq).
B) NH₃(aq) + H₂O(l) → NH₄⁺(aq) + OH^-(aq).
C) HNO₃(aq) + H₂O(l) → NO₃^-(aq) + H₃O⁺(aq).
D) NH₄⁺(aq) + H₂O(l) → NH₃(aq) + H₃O⁺(aq).

Question 8

Identify the strongest acid.

A) H₂O
B) H₂S
C) H₂Se
D) H₂Te
E) Not enough information is available.

Question 9

Which of the following species is amphoteric?

A) CO₃^2-
B) HF
C) NH₄⁺
D) HPO₄^2-
E) None of the above are amphoteric.

Question 10

What is the conjugate acid of HCO₃⁻ ?

A) H₃O⁺
B) H₂O
C) CO₃^2-
D) OH⁻
E) H₂CO₃

Question 11

Which of the following species is amphoteric?

A) HPO₄^-
B) H₃O⁺
C) PO₄^3-
D) Cl^-
E) None of the above are amphoteric.

Question 12

Which of the following statements is TRUE?

A) A strong acid is composed of a proton and an anion that have a very strong attraction for one another.
B) A weak base is composed of a cation and an anion with a very weak attraction between them.
C) A strong acid has a strong conjugate base.
D) The conjugate base of a very weak acid is stronger than the conjugate base of a strong acid.
E) None of the above statements are true.

Question 13

Give the characteristics of a strong acid.

A) ionizes completely in aqueous solutions
B) has equilibrium far to the right
C) has a polar bond
D) has a weaker bond to hydrogen
E) all of the above

Question 14

________ is found in carbonated beverages due to the reaction of carbon dioxide with water.

A) CH₃COOH
B) H₂CO₃
C) HCOOH
D) H₃C₆H₅O₇
E) CH₃CH₂COOH

Question 15

Which of the following is TRUE?

A) A neutral solution contains [H₂O] = [H₃O⁺]
B) A neutral solution does not contain any H₃O⁺ or OH^-
C) An acidic solution has [H₃O⁺] > [OH⁻]
D) A basic solution does not contain H₃O⁺
E) None of the above are true.

Question 16

________ is the active component in vinegar.

A) CH₃COOH
B) H₂CO₃
C) HCOOH
D) H₃C₆H₅O₇
E) CH₃CH₂COOH

Question 17

Identify the weakest acid.

A) HF
B) HCl
C) HBr
D) HI
E) Not enough information is available.

Question 18

Identify the weak diprotic acid.

A) CH₃COOH
B) HCOOH
C) H₃PO₄
D) H₂SO₄
E) H₂CO₃

Question 19

Place the following in order of increasing acid strength. HBrO₂ HBrO₃ HBrO HBrO₄

A) HBrO₂ < HBrO₄ < HBrO < HBrO₃
B) HBrO < HBrO₂ < HBrO₃ < HBrO₄
C) HBrO₂ < HBrO₃ < HBrO₄ < HBrO
D) HBrO₄ < HBrO₂ < HBrO₃ < HBrO
E) HBrO < HBrO₄ < HBrO₃ < HBrO₂

Question 20

The stronger the acid,then which of the following is TRUE?

A) The stronger the conjugate acid.
B) The stronger the conjugate base.
C) The weaker the conjugate base.
D) The weaker the conjugate acid.
E) None of the above

Question 21

Calculate the pOH of a solution that contains 7.8 × 10^-6 M OH⁻ at 25°C.

A) 1.28
B) 5.11
C) 12.72
D) 8.89
E) 9.64

Question 22

Calculate the concentration of H₃O⁺ in a solution that contains 6.25 × 10^-9 M OH⁻ at 25°C.Identify the solution as acidic,basic,or neutral.

A) 6.38 × 10^-9 M, basic
B) 1.60 × 10^-6 M, acidic
C) 7.94 × 10^-11 M, acidic
D) 7.38 × 10^-3 M, basic
E) 4.92× 10^-5 M, acidic

Question 23

Calculate the pH of a solution that contains 7.8 × 10^-6 M OH⁻ at 25°C.

A) 1.28
B) 5.11
C) 12.72
D) 8.89
E) 9.64

Question 24

What is the pH of pure water at 40.0°C if the K_w at this temperature is 2.92 × 10^-14?

A) 6.767
B) 0.465
C) 7.000
D) 7.233
E) 8.446

Question 25

Calculate the hydronium ion concentration in an aqueous solution with a pOH of 4.33 at 25°C.

A) 2.1 × 10^-10 M
B) 9.7 × 10^-10 M
C) 4.7 × 10^-5 M
D) 3.8 × 10^-5 M
E) 6.3 × 10^-6 M

Question 26

Determine the pH of a 0.00598 M HClO₄ solution.

A) 11.777
B) 6.434
C) 7.566
D) 2.223
E) 3.558

Question 27

A container of orange juice at 25°C has a hydronium concentration of 1.78 × 10^-3M.What is the pH of the juice?

A) 1.84
B) 3.31
C) 2.75
D) 11.25
E) 7.00

Question 28

Find the percent ionization of a 0.337 M HF solution.The K_a for HF is 3.5 × 10^-4.

A) 1.1 %
B) 1.2 × 10^-2 %
C) 3.2 %
D) 3.5 × 10^-2 %
E) 4.7 %

Question 29

Determine the pH of a 0.023 M HNO₃ solution.

A) 12.36
B) 3.68
C) 1.64
D) 2.30
E) 2.49

Question 30

What is the K_w of pure water at 50.0°C,if the pH is 6.630?

A) 2.34 × 10^-7
B) 5.50 × 10^-14
C) 2.13 × 10^-14
D) 1.00 × 10^-14
E) There is not enough information to calculate the K_w.

Question 31

Calculate the hydronium ion concentration in an aqueous solution with a pH of 4.33 at 25°C.

A) 2.1 × 10^-10 M
B) 9.7 × 10^-10 M
C) 4.7 × 10^-5 M
D) 3.8 × 10^-5 M
E) 6.3 × 10^-6 M

Question 32

Calculate the hydronium ion concentration in an aqueous solution with a pH of 9.85 at 25°C.

A) 7.1 × 10^-5 M
B) 4.2 × 10^-10 M
C) 8.7 × 10^-10 M
D) 6.5 × 10^-5 M
E) 1.4 × 10^-10 M

Question 33

Determine the [H₃O⁺] in a 0.265 M HClO solution.The K_a of HClO is 2.9 × 10^-8.

A) 1.1 × 10^-10 M
B) 7.7 × 10^-9 M
C) 1.3 × 10^-6 M
D) 4.9 × 10^-4 M
E) 8.8 × 10^-5 M

Question 34

Determine the pOH of a 0.00598 M HClO₄ solution.

A) 11.777
B) 6.434
C) 7.566
D) 2.223
E) 3.558

Question 35

Calculate the hydronium ion concentration in an aqueous solution with a pOH of 9.85 at 25°C.

A) 7.1 × 10^-5 M
B) 4.2 × 10^-10 M
C) 8.7 × 10^-10 M
D) 6.5 × 10^-5 M
E) 1.4 × 10^-10 M

Question 36

Calculate the hydroxide ion concentration in an aqueous solution with a pOH of 9.85 at 25°C.

A) 7.1 × 10^-5 M
B) 4.2 × 10^-10 M
C) 8.7 × 10^-10 M
D) 6.5 × 10^-5 M
E) 1.4 × 10^-10 M

Question 37

Calculate the concentration of H₃O⁺ in a solution that contains 5.5 × 10^-5 M OH⁻ at 25°C.Identify the solution as acidic,basic,or neutral.

A) 1.8 × 10^-10 M, basic
B) 1.8 × 10^-10 M, acidic
C) 5.5 × 10^-10 M, neutral
D) 9.2 × 10^-1 M, acidic
E) 9.2 × 10^-1 M, basic

Question 38

Calculate the hydroxide ion concentration in an aqueous solution with a pH of 4.33 at 25°C.

A) 2.1 × 10^-10 M
B) 9.7 × 10^-10 M
C) 4.7 × 10^-5 M
D) 3.8 × 10^-5 M
E) 6.3 × 10^-6 M

Question 39

Calculate the hydroxide ion concentration in an aqueous solution with a pH of 9.85 at 25°C.

A) 7.1 × 10^-5 M
B) 4.2 × 10^-10 M
C) 8.7 × 10^-10 M
D) 6.5 × 10^-5 M
E) 1.4 × 10^-10 M

Question 40

Calculate the concentration of OH⁻ in a solution that contains 3.9 × 10^-4 M H₃O⁺ at 25°C.Identify the solution as acidic,basic,or neutral.

A) 2.6 × 10^-11 M, acidic
B) 2.6 × 10^-11 M, basic
C) 3.9 × 10^-4 M, neutral
D) 2.7 × 10^-2 M, basic
E) 2.7 × 10^-2 M, acidic

Question 41

Determine the [OH^-] concentration of a 0.741 M KOH solution at 25°C.

A) 1.34 × 10^-13 M
B) 1.34 × 10^-14 M
C) 0.741 M
D) 7.41 M
E) none of the above

Question 42

Determine the [OH⁻] concentration in a 0.169 M Ca(OH)₂ solution.

A) 0.338 M
B) 0.169 M
C) 5.92 × 10^-14 M
D) 2.96 × 10^-14 M
E) 0.298 M

Question 43

Determine the pH in a 0.235 M NaOH solution.

A) 13.76
B) 0.24
C) 13.37
D) 0.63
E) 12

Question 44

Determine the pH of a 0.227 M C₅H₅N solution at 25°C.The K_b of C₅H₅N is 1.7 × 10^-9.

A) 4.59
B) 9.41
C) 4.71
D) 10.14
E) 9.29

Question 45

All of the following anions are considered basic EXCEPT

A) F^-.
B) CN^-.
C) PO₄^3-.
D) HPO₄^2-.
E) Cl^-.

Question 46

Determine the pH of a 0.22 M NaF solution at 25°C.The K_a of HF is 3.5 × 10^-5.

A) 10.20
B) 5.10
C) 8.90
D) 11.44
E) 2.56

Question 47

Determine the pOH in a 0.235 M NaOH solution.

A) 13.76
B) 0.24
C) 13.37
D) 0.63
E) 12

Question 48

Determine the K_b for CN⁻ at 25°C.The K_a for HCN is 4.9 × 10^-10.

A) 4.9 × 10^-14
B) 2.3 × 10^-9
C) 1.4 × 10^-5
D) 2.0 × 10^-5
E) 3.7 × 10^-7

Question 49

Which of the following bases is the strongest? The base is followed by its K_b.

A) (CH₃CH₂)₂NH, 8.6 × 10^-4
B) CH₃NH₂, 4.4 × 10^-4
C) C₆H₅NH₂, 4.0 × 10^-10
D) NH₃, 1.76 × 10^-5
E) C₅H₅N, 1.7 × 10^-9

Question 50

Determine the pOH of a 0.227 M C₅H₅N solution at 25°C.The K_b of C₅H₅N is 1.7 × 10^-9.

A) 4.59
B) 9.41
C) 4.71
D) 10.14
E) 9.29

Question 51

Determine the pH of a 0.461 M C₆H₅CO₂H M solution if the K_a of C₆H₅CO₂H is 6.5 × 10^-5.

A) 2.26
B) 4.52
C) 11.74
D) 9.48
E) 5.48

Question 52

All of the following cations are considered acidic EXCEPT

A) Fe²⁺
B) Na⁺
C) Al³⁺
D) NH₄⁺
E) V²⁺

Question 53

Which of the following bases is the weakest? The base is followed by its K_b value.

A) HOCH₂CH₂NH₂, 3.2 × 10^-5
B) NH₃, 1.76 × 10^-5
C) C₅H₅N, 1.7 × 10^-9
D) (CH₃CH₂)₃N, 5.2 × 10^-4
E) Since these are all weak bases, they have the same strength.

Question 54

Determine the pH of a 0.62 M NH₄NO₃ solution at 25°C.The K_b for NH₃ is 1.76 × 10^-5.

A) 2.48
B) 9.27
C) 11.52
D) 4.73
E) 9.45

Question 55

Determine the pH of a 0.188 M NH₃ solution at 25°C.The K_b of NH₃ is 1.76 × 10^-5.

A) 5.480
B) 2.740
C) 8.520
D) 11.260
E) 12.656

Question 56

Which one of the following will form a basic solution in water?

A) NaC₂H₃O₂
B) LiCN
C) KClO₂
D) LiBrO
E) All of the above will form basic solutions.

Question 57

Determine the pOH of a 0.188 M NH₃ solution at 25°C.The K_b of NH₃ is 1.76 × 10^-5.

A) 5.480
B) 2.740
C) 8.520
D) 11.260
E) 12.656

Question 58

Which of the following weak acids has the strongest conjugate base?

A) acetic acid, K_a = 1.8 × 10^-5
B) nitrous acid, K_a = 4.5 × 10^-4
C) dihydrogen phosphate ion, K_a = 6.2 × 10^-8
D) hydrocyanic acid, K_a = 4.0 × 10^-10
E) benzoic acid, K_a = 6.3 × 10^-5

Question 59

Determine the K_a for CH₃NH₃⁺ at 25°C.The K_b for CH₃NH₂ is 4.4 × 10^-4.

A) 3.1 × 10^-10
B) 6.8 × 10^-11
C) 5.6 × 10^-10
D) 2.3 × 10^-3
E) 2.3 × 10^-11

Question 60

Determine the K_a of an acid whose 0.294 M solution has a pH of 2.80.

A) 1.2 × 10^-5
B) 8.5 × 10^-6
C) 2.7
D) 4.9 × 10^-7
E) 5.4 × 10^-3

Question 61

Determine the concentration of CO₃^2- ions in a 0.18 M H₂CO₃ solution.Carbonic acid is a diprotic acid whose K_a1 = 4.3 × 10^-7 and K_a2 = 5.6 × 10^-11.

A) 2.8 × 10^-4 M
B) 3.2 × 10^-6 M
C) 5.6 × 10^-11 M
D) 4.3 × 10^-7 M
E) 6.9 × 10^-8 M

Question 62

The stomach excretes ________ to kill microorganisms and to activate enzymes that break down food.

A) CH₃COOH
B) HBr
C) LiHCO₃
D) HCl
E) HNO₃

Question 63

Determine the pH of a solution that is 0.15 M HClO₂ (K_a = 1.1 × 10^-2)and 0.15 M HClO (K_a = 2.9 × 10^-8).

A) 4.18
B) 9.82
C) 12.55
D) 1.39
E) 3.55

Question 64

Which of the following is an Arrhenius base?

A) CH₃CO₂H
B) KOH
C) CH₃OH
D) Na F
E) More than one of these compounds is an Arrhenius base.

Question 65

A Lewis base

A) donates electrons.
B) accepts electrons.
C) donates a proton.
D) accepts a proton.
E) donates more than one proton.

Question 66

Calculate the hydronium ion concentration in an aqueous solution with a pH of 11.7 at 25°C.

A) 5.7 × 10^-11 M
B) 1.9× 10^-12 M
C) 5.4 × 10^-2 M
D) 6.4 × 10^-7 M
E) 9.5× 10^-3 M

Question 67

Determine the pOH in a 2.58 × 10^-3 M KOH solution.

A) 11.4
B) 2.59
C) 9.33
D) 4.67
E) 7.00

Question 68

Determine the pH of a 0.580 M KCH₃CO₂ solution at 25°C.The K_a of CH₃CO₂H is 1.80 × 10^-5.

A) 9.25
B) 4.75
C) 7.00
D) 12.5
E) 1.47

Question 69

Which of these is an example of a polyprotic oxyacid?

A) HClO₃
B) CH₃COOH
C) H₂SO₃
D) H₂S
E) None of the above

Question 70

Which of the following is an Arrhenius acid?

A) H₂SO₄
B) NaOH
C) NH₂CH₃
D) CH₃CH₃
E) More than one of these is an Arrhenius acid.

Question 71

Identify the base that is in Drano.

A) LiOH
B) NaOH
C) NaHCO₃
D) Li₂CO₃
E) NH₃

Question 72

Determine the pH of a 0.18 M H₂CO₃ solution.Carbonic acid is a diprotic acid whose K_a1 = 4.3 × 10^-7 and K_a2 = 5.6 × 10^-11.

A) 11.00
B) 10.44
C) 5.50
D) 4.31
E) 3.56

Question 73

When dissolved in water,which compound is generally considered to be an Arrhenius acid?

A) H NO₂
B) KOH
C) Li F
D) CH₃OH

Question 74

Determine the K_a of an acid that has a pH of 4.67 and a concentration of 0.448 M.

A) 5.8 × 10^-8
B) 3.3 × 10^-11
C) 9.9 × 10^-5
D) 4.6 × 10^-7
E) 1.0 × 10^-9

Question 75

Identify the acid that is in car batteries.

A) H₂SO₄
B) HNO₃
C) H₂CO₃
D) CH₃COOH
E) HCl

Question 76

Identify the acid that is in vinegar.

A) H₂SO₄
B) HNO₃
C) Li₂CO₃
D) CH₃COOH
E) HF

Question 77

A Lewis acid

A) donates electrons.
B) accepts electrons.
C) donates a proton.
D) accepts a proton.
E) donates more than one proton.

Question 78

Identify the base that is in baking soda.

A) RbOH
B) NaOH
C) NaHCO₃
D) K₂CO₃
E) NH₃

Question 79

In a triprotic acid,which K_a has the highest value?

A) K_a1
B) K_a2
C) K_a3
D) K_b1
E) K_b2

Question 80

Which of the following solutions would have the lowest pH? Assume that they are all 0.10 M in acid at 25^∘C.The acid is followed by its K_a value.

A) HF, 3.5 × 10^-4
B) HCN, 4.9 × 10^-10
C) HNO₂, 4.6 × 10^-4
D) HCHO₂, 1.8 × 10^-4
E) HClO₂, 1.1 × 10^-2