Deck 8: Acids and Bases

Question 1

When solid sodium hydroxide is dissolved in water which of the following species is not present in the solution?

A) H₂O(l)
B) Na⁺(aq)
C) OH-(aq)
D) None, they are all present.

Answer 1

D

Question 2

The species H₃O⁺ can be called which of the following?

A) heavy water
B) hydrogen ion
C) hydronium ion
D) all of these

Answer 2

C

Question 3

When solid sodium hydroxide is dissolved in water which of the following species is not present in the solution?

A) NaOH(aq)
B) H₂O(l)
C) OH-(aq)
D) None, they are all present.

Answer 3

A

Question 4

Which of the following can be characterized as a strong base?

A) LiOH
B) KOH
C) both a and b
D) neither a nor b

Question 5

Which of the following can be characterized as a strong acid?

A) 0.001 M HCl
B) 3.0 M HCl
C) both a and b
D) neither a nor b

Question 6

When hydrogen chloride gas is dissolved in water which of the following species is not present in the solution?

A) HCl(aq)
B) H₂O(l)
C) Cl^-(aq)
D) None, they are all present.

Question 7

According to Arrhenius which species is associated with all acids?

A) H₃O⁺
B) OH^-
C) H₂O
D) none of these

Question 8

Which of the following can be characterized as a strong base?

A) Ba(OH)₂
B) NH₃
C) both a and b
D) neither a nor b

Question 9

Which of the following can be characterized as a strong acid?

A) HF
B) HCl
C) both a and b
D) neither a nor b

Question 10

Why does the label ammonium hydroxide on a bottle give a false impression about the bottle=s contents?

A) There is a large amount of NH₄⁺(aq) but only a small amount of OH-(aq).
B) There is a small amount of NH₄⁺(aq) but only a large amount of OH-(aq).
C) There is a large amount of NH₃(aq) but only small amount of OH-(aq).
D) None of the above, the label accurately describes the contents.

Question 11

Which of the following can be characterized as a strong acid?

A) 0.001 M HCl
B) 3.0 M CH₃COOH
C) both a and b
D) neither a nor b

Question 12

The species H⁺ can be called which of the following?

A) hydrogen ion
B) proton
C) either a or b
D) neither a nor b

Question 13

Which of the following occurs when hydrogen chloride gas is dissolved in water to form hydrochloric acid?

A) A complex between HCl and water is formed.
B) H⁺ is transferred from HCl to water.
C) H⁺ is transferred from water to HCl.
D) There is no reaction, HCl molecules remain present.

Question 14

Which of the following can be characterized as a strong base?

A) 0.001 M KOH
B) 3.0 M NH₃
C) both a and b
D) neither a nor b

Question 15

Which of the following can be characterized as a strong base?

A) 0.001 M KOH
B) 3.0 M KOH
C) both a and b
D) neither a nor b

Question 16

According to Arrhenius which species is associated with all bases?

A) H₃O⁺
B) OH^-
C) H₂O
D) none of these

Question 17

Which of the following acids is the acid found in gastric fluid?

A) acetic
B) hydrochloric
C) nitric
D) sulfuric

Question 18

Which of the following occurs when NaOH is dissolved in water to form a basic solution?

A) A complex between NaOH and water is formed.
B) NaOH breaks up to form Na⁺(aq), H⁺(aq) and O^2-(aq).
C) NaOH breaks up to form Na⁺(aq) and OH^-(aq).
D) The water molecule loses an H⁺.

Question 19

Which of the following occurs when the weak base ammonia, NH₃, is dissolved in water?

A) A very small number of ammonia molecules break up.
B) A very small number of ammonia molecules take an H⁺ from the water.
C) A very small number of molecules of NH₄OH are formed.
D) A very small number of water molecules take an H⁺ from ammonia.

Question 20

Which of the following can be characterized as a strong acid?

A) HNO₃
B) H₂SO₄
C) both a and b
D) neither a nor b

Question 21

Which of the following is the conjugate acid of water?

A) HCl
B) H₃O⁺
C) NH₄⁺
D) OH-

Question 22

Which base is an important starting material in the manufacture of fertilizers?

A) LiOH
B) Mg(OH)₂
C) NaOH
D) NH₃

Question 23

Which base is sometimes used as a laxative?

A) LiOH
B) Mg(OH)₂
C) NaOH
D) NH₃

Question 24

Which of the following is not a base?

A) HPO₄^2-
B) OH-
C) NH₃
D) None, they are all bases.

Question 25

Which of the following bases can accepted only one proton?

A) NH₃
B) CH₃NH₂
C) (CH₃)₂NH
D) all of them

Question 26

Which of the following can be characterized as a strong electrolyte?

A) 0.001 M HCl
B) 3.0 M HCl
C) both a and b
D) neither a nor b

Question 27

Ions produced from which of the following acids play an important role in biochemistry?

A) acetic
B) boric
C) nitric
D) phosphoric

Question 28

Which of the following can be characterized as a strong electrolyte?

A) 0.001 M HCl
B) 3.0 M CH₃COOH
C) both a and b
D) neither a nor b

Question 29

Which of the following is not an acid?

A) H₃O⁺
B) H₂CO₃
C) HPO₄^2-
D) None, they are all acids.

Question 30

How many protons can be lost by acetic acid, CH₃COOH?

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

Question 31

Which of the following is the conjugate base of water?

A) H₃O⁺
B) NaOH
C) OH-
D) O^2-

Question 32

Which of the following can be characterized as a strong electrolyte?

A) 0.001 M KOH
B) 3.0 M KOH
C) both a and b
D) neither a nor b

Question 33

How many protons can be lost by citric acid, H₃C₆H₅O₆?

A) 1
B) 3
C) 5
D) 8

Question 34

Which of the following is a diprotic acid?

A) HCl
B) HNO₃
C) H₂SO₄
D) H₃PO₄

Question 35

Which of the following is the Brønsted-Lowry definition of an acid?

A) a hydroxide ion acceptor
B) a proton acceptor
C) a proton donor
D) none of these

Question 36

Which of the following is the conjugate acid of ammonia, NH₃?

A) H⁺
B) H₃O⁺
C) NH₂-
D) NH₄⁺

Question 37

Which of the following is the conjugate base of acetic acid, CH₃COOH?

A) H₃O⁺
B) CH₃COOH₂⁺
C) CH₃COO-
D) OH-

Question 38

Which of the following is the Brønsted-Lowry definition of a base?

A) a hydroxide ion acceptor
B) a proton acceptor
C) a proton donor
D) none of these

Question 39

Which of the following acids has long been used as a test for proteins?

A) acetic
B) boric
C) nitric
D) sulfuric

Question 40

Which of the following is a triprotic acid?

A) HCl
B) HNO₃
C) H₂SO₄
D) H₃PO₄

Question 41

Which of the following bases has the weakest conjugate acid?

A) CH₃COO^-
B) C₆H₅O^-
C) HSO₄^-
D) H₂PO₄^-

Question 42

What is the name of the acid which dissociates to give the nitrate ion, NO₃^-?

A) hydronitric acid
B) nitric acid
C) nitritic acid
D) nitrous acid

Question 43

Which of the following is the conjugate base of HPO₄^2-?

A) H₃PO₄
B) H₂PO₄-
C) PO₄^3-
D) OH-

Question 44

Which of the following is the conjugate base of H₂PO₄^-?

A) H₃PO₄
B) HPO₄^2-
C) PO₄^3-
D) OH-

Question 45

Which of the following species can be characterized as amphiprotic?

A) H₂O
B) HCO₃-
C) HPO₄^2-
D) all of them

Question 46

What is the name of the acid which dissociates to give the cyanide ion, CN^-?

A) cyanic acid
B) cyanidic acid
C) cyanous
D) hydrocyanic acid

Question 47

Which of the following is the conjugate acid of HPO₄^2-

A) H₃PO₄
B) H₂PO₄-
C) PO₄^3-
D) H₃O⁺

Question 48

What is the name of the acid which dissociates to give the nitrite ion, NO₂^-?

A) hydronitric acid
B) nitric acid
C) nitritic acid
D) nitrous acid

Question 49

Which of the following is the conjugate acid of H₂PO₄^-?

A) H₃PO₄
B) HPO₄^2-
C) PO₄^3-
D) H₃O⁺

Question 50

Sulfites, salts of the anion, SO₃^2- are found in wines as preservatives. The acid associated with the sulfite ion is H₂SO₃. What is the name of H₂SO₃?

A) hydrosulfuric acid
B) hydrosulfuous acid
C) sulfuric acid
D) sulfurous acid

Question 51

Which of the following statements best describes the acid/base relationship?

A) As acid strengths increase conjugate base strengths increase.
B) As base strengths increase conjugate acid strengths decrease.
C) both a and b
D) neither a nor b

Question 52

In an acid-base equilibrium the equilibrium lies in the direction which favors which species?

A) the stronger acid
B) the stronger base
C) both a and b
D) neither a nor b

Question 53

Which of the following species is not amphiprotic?

A) C₂H₃O₂-
B) HC₃H₂O₄-
C) HC₄H₄O₄-
D) None, all of them are amphiprotic.

Question 54

Which of the following is the conjugate base of H₃PO₄?

A) H₂PO₄-
B) HPO₄^2-
C) PO₄^3-
D) OH-

Question 55

Which of the following is the conjugate acid of PO₄^3-?

A) H₃PO₄
B) H₂PO₄-
C) HPO₄^2-
D) H₃O⁺

Question 56

Which of the following acids has the strongest conjugate base?

A) CH₃COOH
B) C₆H₅OH
C) H₂SO₄
D) H₃PO₄

Question 57

Which of the following statements best describes the acid/base relationship?

A) As acid strengths decrease conjugate base strengths increase.
B) As base strengths decrease conjugate acid strengths decrease.
C) both a and b
D) neither a and b

Question 58

Which of the following acids has the weakest conjugate base?

A) CH₃COOH
B) C₆H₅OH
C) H₂SO₄
D) H₃PO₄

Question 59

Which of the following statements best describes the acid/base relationship?

A) As acid strengths increase conjugate base strengths increase.
B) As base strengths increase conjugate acid strengths increase.
C) both a and b
D) neither a nor b

Question 60

Which of the following bases has the strongest conjugate acid?

A) CH₃COO^-
B) C₆H₅O^-
C) HSO₄^-
D) H₂PO₄^-

Question 61

When comparing the strength of two weak acids which factor do we use to determine which is the stronger of the two?

A) the formula weights of the acids
B) the number of protons the acids can lose
C) the size of the acid dissociation constants
D) none of the above

Question 62

Hydrocyanic acid, HCN, is a weaker acid than ammonium ion, NH₄⁺. When hydrocyanic acid reacts with ammonia, NH₃, what species are present in the solution in the largest amount?

A) hydrocyanic acid, HCN, and ammonia, NH₃
B) hydrocyanic acid, HCN, and ammonium ion, NH₄⁺
C) cyanide ion, CN-, and ammonia, NH₃
D) cyanide ion, CN-, and ammonium ion, NH₄⁺

Question 63

When acetic acid is dissolved in water which of the following is true of the equilibrium which is established as represented below?

A) It lies very far to the left.
B) It lies slightly to the left.
C) It lies very far to the right.
D) It lies slightly to the right.

Question 64

When comparing two acids which of the following is true?

A) the stronger acid has the larger K_a
B) the stronger acid has the smaller pK_a
C) both a and b
D) neither a nor b

Question 65

Consider the following hypothetical acid-base reaction. A(aq) + B(aq) C(aq) + D(aq)
Weaker acid weaker base stronger acid stronger base

A) The position of the equilibrium favors the forward reaction.
B) The position of the equilibrium favors the reverse reaction.
C) Neither the forward nor the reverse reaction are favored at equilibrium.
D) The position of equilibrium cannot be predicted from the given data.

Question 66

What are the two acids in the following reaction? NH₄⁺(aq) + HPO₄^2- NH₃ + H₂PO₄^-

A) NH₄⁺ and HPO₄2^-
B) NH₄⁺ and NH₃
C) HPO₄2^- and H₂PO₄^-
D) NH₄⁺ and H₂PO₄^-

Question 67

When comparing the strength of two weak acids which factor do we use to determine which is the stronger of the two?

A) the formula weights of the acids
B) the number of protons the acids can lose
C) the values of the pK_a's of the acids
D) none of the above

Question 68

The pK_a of hydrocyanic acid is 9.31. What is the K_a of hydrocyanic acid?

A) 1.3 × 10^-24
B) 1.3 × 10^-10
C) 4.9 × 10^-10
D) 2.0 × 10⁹

Question 69

In an acid-base equilibrium the equilibrium lies in the direction which favors which species?

A) the weaker acid
B) the weaker base
C) both a and b
D) neither a nor b

Question 70

Cyanide ion, CN-, is a stronger base than ammonia, NH₃. When ammonia reacts with hydrocyanic acid, HCN, what species are present in the solution in the largest amount?

A) hydrocyanic acid, HCN, and ammonia, NH₃
B) hydrocyanic acid, HCN, and ammonium ion, NH₄⁺
C) cyanide ion, CN-, and ammonia, NH₃
D) cyanide ion, CN-, and ammonium ion, NH₄⁺

Question 71

The K_a for lactic acid is 8.4 × 10^-4. What is the pK_a of lactic acid?

A) -10.92
B) -3.08
C) 3.08
D) 10.92

Question 72

In an acid-base equilibrium the equilibrium lies in the direction which favors which species?

A) the stronger acid
B) the weaker base
C) both a and b
D) neither a nor b

Question 73

When HCl is dissolved in water which of the following is true of the equilibrium which is established?

A) It lies virtually completely to the left.
B) It lies slightly to the left.
C) It lies virtually completely to the right.
D) It lies slightly to the right.

Question 74

Acetic acid, CH₃COOH, is a stronger acid than the ammonium ion, NH₄⁺. When acetic acid reacts with ammonia, NH₃, what species are present in the solution in the largest amount?

A) acetic acid, CH₃COOH and ammonia, NH₃
B) acetic acid, CH₃COOH, and ammonium, NH₄⁺
C) acetate ion, CH₃COO^-, and ammonia, NH₃
D) acetate ion, CH₃COO^-, and ammonium ion, NH₄⁺

Question 75

The K_a for boric acid is 7.3 × 10^¯10. What is the pK_a of boric acid?

A) -9.14
B) -4.86
C) 4.86
D) 9.14

Question 76

Ammonia , NH₃, is a stronger base than the acetate ion, CH₃COO^-. When acetic acid, CH₃COOH, reacts with ammonia, NH₃, what species are present in the solution in the largest amount?

A) acetic acid, CH₃COOH, and ammonia, NH₃
B) acetic acid, CH₃COOH, and ammonium, NH₄⁺
C) acetate ion, CH₃COO^-, and ammonia, NH₃
D) acetate ion, CH₃COO^-, and ammonium ion, NH₄⁺

Question 77

When comparing two acids which of the following is true?

A) the stronger acid has the larger K_a
B) the stronger acid has the larger pK_a
C) both a and b
D) neither a nor b

Question 78

When comparing the strength of two weak acids which factor(s) do we use to determine which is the stronger of the two?

A) the size of the acid dissociation constants
B) the values of the pK_a's of the acids
C) either a or b
D) neither a nor b

Question 79

When NH₃ is dissolved in water which of the following is true of the equilibrium which is established as represented below? NH₃(aq) + H₂O(l) NH₄⁺(aq) + OH^-(aq)

A) It lies virtually completely to the left.
B) It lies slightly to the left.
C) It lies virtually completely to the right.
D) It lies slightly to the right.

Question 80

When comparing two acids which of the following is true?

A) the stronger acid has the smaller K_a
B) the stronger acid has the larger pK_a
C) both a and b
D) neither a nor b