Deck 15: Acids and Bases

Question 1

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.

Answer 1

The conjugate base of a very weak acid is stronger than the conjugate base of a strong acid.

Question 2

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

A)HCl
B)HClO₄
C)HNO₃
D)HCN
E)HI

Answer 2

HCN

Question 3

What is the conjugate acid of HCO₃^⁻?

A)H₃O⁺
B)H₂O
C)CO₃^2-
D)OH^⁻
E)H₂CO₃

Answer 3

H₂CO₃

Question 4

Identify the weak diprotic acid.

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

Question 5

Identify the triprotic acid.

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

Question 6

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 7

Which of the following is a weak acid?

A)HClO₄
B)H₂SO₄
C)HCl
D)HCO₂H
E)HNO₃

Question 8

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 9

Which of the following is a Br∅nsted-Lowry acid?

A)NH₄⁺
B)CH₄
C)NH₂^-
D)NH₃
E)Br₂

Question 10

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

Question 11

Which of the following is an Arrhenius acid?

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

Question 12

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 13

What is the conjugate base of H₂PO₄^⁻?

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

Question 14

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 15

Which of the following is a Br∅nsted-Lowry base?

A)CH₄
B)HCN
C)NH₃
D)Cl₂
E)None of the above are Br∅nsted-Lowry bases.

Question 16

How many of the following are weak acids?
HCN HClO₂ HNO₃ H₂PO₄^⁻

A)0
B)1
C)3
D)4
E)2

Question 17

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.

Question 18

Which of the following solutions would have the most basic 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 19

Which of the following is a strong acid?

A)C₆H₅CO₂H
B)HCN
C)HClO₄
D)NH₄⁺
E)H₂O

Question 20

Which of the following is an Arrhenius base?

A)CH₃CO₂H
B)NaOH
C)CH₃OH
D)LiCl
E)More than one of these compounds is an Arrhenius base.

Question 21

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 22

Determine the pH of a 0.00598 M HClO₄ solution.

A)1.777
B)6.434
C)7.566
D)2.223
E)3.558

Question 23

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 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

Which of the following acids is the strongest? 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 26

Determine the pOH 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 27

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 28

Which of the following is a polyprotic acid?

A)HF
B)H₂SO₄
C)HCN
D)CH₄
E)HC₂H₃O₂

Question 29

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 30

Which of the following acids is the weakest? The acid is followed by its K_a value.

A)HC₂H₃O₂,1.8 × 10^-5
B)HIO,2.3 × 10^-11
C)HBrO,2.3 × 10^-9
D)HClO,2.9 × 10^-8
E)C₆H₅CO₂H,6.3 × 10^-5

Question 31

Calculate the pH of a solution that contains 2.4 × 10^-5 M H₃O^⁺ at 25°C.

A)2.40
B)9.38
C)4.62
D)11.60
E)4.17

Question 32

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 33

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 34

Calculate the pH of a solution that contains 3.9 × 10^-4 M H₃O^⁺ at 25°C.

A)4.59
B)3.41
C)10.59
D)9.41
E)0.59

Question 35

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 36

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 37

Calculate the pOH of a solution that contains 3.9 × 10^-4 M H₃O^⁺ at 25°C.

A)4.59
B)3.31
C)10.59
D)9.14
E)0.59

Question 38

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 39

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 40

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 41

Give the characteristics of a strong acid.

A)Ionizes completely in aqueous solutions.
B)Has a very electronegative atom attached to the oxygen.
C)Has a polar bond.
D)Has a weaker bond to hydrogen.
E)All of the above.

Question 42

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 43

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 44

Which one of the following will form an acidic solution in water?

A)NH₄Cl
B)NaF
C)LiI
D)KNO₃
E)None of the above solutions will be acidic.

Question 45

Which of the following is a weak base?

A)NH(CH₃)₂
B)N₂
C)NaOH
D)CH₂CH₂
E)None of the above are weak bases.

Question 46

Determine the [OH⁻] concentration in a 0.235 M NaOH solution.

A)4.25 × 10^-14 M
B)0.470 M
C)2.13 × 10^-14 M
D)0.198 M
E)0.235 M

Question 47

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 48

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 49

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 50

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 51

Determine the pH of a 0.741 M KOH solution at 25°C.

A)0.13
B)13.87
C)0.17
D)12.65
E)11.88

Question 52

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 53

Give the pH of 0.330 M phosphoric acid.For phosphoric acid,K_a1 = 7.5 × 10^-3,K_a2 = 6.2 × 10^-8,and K_a3 = 4.2 × 10^-13.

A)1.30
B)3.84
C)6.43
D)2.61
E)5.68

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 0.22 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 56

Which of the following is a strong base?

A)Cl^-
B)NH₃
C)CH₃OH
D)NO₃^⁻
E)KOH

Question 57

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 58

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 59

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 60

Determine the pH of a 0.116 M Ba(OH)₂ solution at 25°C.

A)8.62
B)13.06
C)13.37
D)0.63
E)12.56

Question 61

Which Br∅nsted-Lowry acid is not considered to be a strong acid in water?

A)HI
B)HBr
C)H₂SO₃
D)H NO₃

Question 62

Which of the following is a Lewis base?

A)AlF₃
B)H₂O
C)SiF₄
D)C₅H₁₂
E)None of the above are Lewis bases.

Question 63

Match the following.
Lewis acid

A)electron pair donor
B)proton donor
C)produces protons in aqueous solution
D)produces hydroxide ions in aqueous solution
E)electron pair acceptor
F)proton acceptor

Question 64

Describe the relationship between molecular structure and acid strength.

Question 65

What is the autoionization of water?

Question 66

Define a Lewis acid.

Question 67

Do both protons ionize instantaneously from a diprotic acid such as H₂CO₃? Explain your answer.

Question 68

What does the term amphoteric mean?

Question 69

Match the following.
Arrhenius acid

A)electron pair donor
B)proton donor
C)produces protons in aqueous solution
D)produces hydroxide ions in aqueous solution
E)electron pair acceptor
F)proton acceptor

Question 70

Calculate the hydronium ion concentration in an aqueous solution that contains 2.50 × 10^-6 M in hydroxide ion.

A)4.00 × 10^-7 M
B)4.00 × 10^-8 M
C)4.00 × 10^-9 M
D)5.00 × 10^-9 M

Question 71

Match the following.
Lewis base

A)electron pair donor
B)proton donor
C)produces protons in aqueous solution
D)produces hydroxide ions in aqueous solution
E)electron pair acceptor
F)proton acceptor

Question 72

Calculate the hydroxide ion concentration in an aqueous solution that contains 3.50 × 10^-4 M in hydronium ion.

A)2.86 × 10^-3 M
B)2.86 × 10^-10 M
C)2.86 × 10^-11 M
D)3.50 × 10^-11 M

Question 73

Match the following.
Br∅nsted-Lowry base

A)electron pair donor
B)proton donor
C)produces protons in aqueous solution
D)produces hydroxide ions in aqueous solution
E)electron pair acceptor
F)proton acceptor

Question 74

What is the difference between a strong and weak acid?

Question 75

Identify the strongest acid.

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

Question 76

Identify the strongest acid.

A)HClO₄
B)HClO₃
C)HClO₂
D)HClO
E)Not enough information is given.

Question 77

Which of the following is a Lewis acid?

A)BCl₃
B)CH₄
C)NH₃
D)CHCl₃
E)None of the above are Lewis acids.

Question 78

Match the following.
Br∅nsted-Lowry acid

A)electron pair donor
B)proton donor
C)produces protons in aqueous solution
D)produces hydroxide ions in aqueous solution
E)electron pair acceptor
F)proton acceptor

Question 79

Match the following.
Arrhenius base

A)electron pair donor
B)proton donor
C)produces protons in aqueous solution
D)produces hydroxide ions in aqueous solution
E)electron pair acceptor
F)proton acceptor

Question 80

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

A)HNO₂
B)KOH
C)Li F
D)CH₃OH