Deck 10: Acids and Bases

Question 1

The base forms a new ________ bond in a Brønsted-Lowry acid-base reaction.

A)covalent
B)aquo
C)hydrogen
D)ionic
E)metallic

Answer 1

covalent

Question 2

Consider the reaction: H₂SO₃ + HCO₃^-
H₂CO₃ + HSO₃^-

A) Identify the acid,base,conjugate acid and conjugate base.
B) Identify two substances from the reaction which could be used to prepare a buffer.

Answer 2

A) Acid: H₂SO₃;Conjugate Base: HSO₃^-;Base: HCO₃^-;Conjugate Acid: H₂CO₃
B) Buffers: either conjugate acid base pair

Question 3

The classification of an acid or a base as weak or strong is determined by

A)the solubility of the acid or base.
B)the extent of dissociation of the dissolved acid or base.
C)the concentrations of the acid or base.
D)more than one choice is correct.

Answer 3

the extent of dissociation of the dissolved acid or base.

Question 4

Which of the following is a triprotic acid?

A)H₃PO₄
B)CH₃COOH
C)HNO₃
D)NH₃
E)Al(OH)₃

Question 5

When acids and bases react the product other than water is a

A)hydrogen ion.
B)hydroxide ion.
C)hydronium ion.
D)metal.
E)salt.

Question 6

A Brønsted-Lowry base is a substance which

A)produces hydrogen ions in aqueous solution.
B)produces hydroxide ions in aqueous solution.
C)donates protons to other substances.
D)accepts protons from other substances.
E)accepts hydronium ions from other substances.

Question 7

Which of the following is a diprotic acid?

A)acetic acid
B)hydrochloric acid
C)phosphoric acid
D)sulfuric acid
E)nitric acid

Question 8

C₅H₅N + H₂CO₃ C₅H₆N ⁺+ HCO₃^-
In the reaction shown,the conjugate acid of C₅H₅N is

A) C₅H₅N
B) H₂CO₃
C) C₅H₆N ⁺
D)HCO₃^-.
E) H₃O⁺

Question 9

A necessary requirement for a Brønsted base is

A)the presence of water as a reaction medium.
B)the presence of hydroxide in its formula.
C)a lone pair of electrons in its Lewis dot structure.
D)the production of hydronium ion upon reaction with water.
E)the presence of a metal ion in its formula.

Question 10

What is the conjugate base of HSO₄^-?

A)SO₄^2-
B)H₂SO₄
C)H₃O⁺
D)OH^-
E)H₂SO₃

Question 11

A Brønsted-Lowry acid is a substance which

A)produces hydrogen ions in aqueous solution.
B)produces hydroxide ions in aqueous solution.
C)donates protons to other substances.
D)accepts protons from other substances.
E)accepts hydronium ions from other substances.

Question 12

Acetic acid is a weak acid in water because it is

A)dilute.
B)only slightly soluble.
C)unable to hold onto its hydrogen ion.
D)only slightly dissociated into ions.
E)completely dissociated into hydronium ions and acetate ions.

Question 13

According to Brønsted-Lowry theory,acid-base reactions can be described as ________ reactions.

A)electrolytic
B)electron transfer
C)gas phase
D)nuclear transfer
E)proton transfer

Question 14

Consider the following reaction: NO₂^- + HCO₃^-
CO₃^-2 + HNO₂
Identify the acid,base,conjugate acid and conjugate base.

Question 15

CH₃NH₂ + HCl CH₃NH₃⁺ + Cl^-
A conjugate acid-base pair in the reaction shown is ________ and ________.

A)CH₃NH₂;HCl
B)CH₃NH₂;Cl^-
C)CH₃NH₃⁺;Cl^-
D)HCl;Cl^-
E)HCl;H₃O⁺

Question 16

Which of the following cannot act as a Brønsted base?

A)HCO₃^-
B)CO₃^2-
C)NH₃
D)NH₂^-
E)NH₄⁺

Question 17

In the following equation,which of the following is acting as the Bronsted acid?
HClO₄ + H₂O → ClO₄^- + H₃O⁺

A)HClO₄
B)H₂O
C)ClO₄^-
D)H₃O⁺

Question 18

What is the conjugate acid of HSO₄^-?

A)SO₄^2-
B)H₂SO₄
C)H₃O⁺
D)OH^-
E)H₂SO₃

Question 19

Which statement concerning Arrhenius acid-base theory is not correct?

A)An Arrhenius acid produces hydrogen ions in water solution.
B)An Arrhenius base produces hydroxide ions in water solution.
C)A neutralization reaction produces water plus a salt.
D)Acid-base reactions must take place in aqueous solution.
E)none of the above

Question 20

The H₃O⁺ ion is called the ________ ion.

A)hydroxide
B)hydronium
C)hydrogen
D)protium
E)water

Question 21

Hydrogen cyanide,HCN,is a weak acid.Which equation best represents its aqueous chemistry?

A)HCN(aq)+ H₂O(l) CN^-(aq)+ H₃O⁺(aq)

B)HCN(aq)+ H₂O(l) H₂CN⁺(aq)+ OH^-(aq)

C)HCN(aq) H⁺(aq)+ CN^-(aq)

D)HCN(aq) H^-(aq)+ CN⁺(aq)

E)H₂O(l) H⁺(aq)+ OH^-(aq)

Question 22

What is the conjugate acid of water?

A)H₂O(l)
B)H₃O⁺(aq)
C)OH^-(aq)
D)H⁺(aq)
E)O₂^-(aq)

Question 23

Propionic acid (CH₃CH₂COOH)has a Ka = 1.3 × 10^-5 and phosphoric acid (H₃PO₄)has a Ka = 7.5 10 ^-3.Write the conjugate base for each.Which one is the stronger base?

Question 24

Which compound has a value of K_a that is close to 10^-5?

A)NaCl
B)HNO₃
C)CH₃CH₂CO₂H
D)KOH
E)NH₃

Question 25

Which compound has a very large value of K_a in aqueous solution?

A)NaCl
B)HNO₃
C)H₃PO₄
D)KOH
E)NH₃

Question 26

What is the correct Ka expression for the reaction below?
H₂PO₄^-(aq)+ H₂O(l) HPO₄^2-(aq)+ H₃O⁺(aq)

A)

B)

C)

D)

E)

Question 27

Which reaction best illustrates the behavior of the weak base H₂PO₄^- in aqueous solution?

A)H₂PO₄^-(aq)+ H₂O(l) HPO₄^2-(aq)+ H₃O⁺(aq)
B)H₂PO₄^-(aq)+ H₂O(l) H₃PO₄⁽aq)+ OH^-(aq)
C)H₂PO₄^-(aq) 2H⁺(aq)+ PO₄^3-(aq)
D)H₂PO₄^-(aq) H⁺(aq)+ HPO₄^2-(aq)
E)H₂PO₄^-(aq)+ H⁺(aq) H₃PO₄⁽aq)

Question 28

At 25°C,the value of K_w is

A)1.00.
B)1.00 × 10^-7.
C)1.00 × 10^-14.
D)1.00 × 10^7.
E)1.00 × 10^14.

Question 29

What is the correct Ka expression for the reaction below?
CH₃COOH(aq)+ H₂O(l) CH₃COO^-(aq)+ H₃O⁺(aq)

A)

B)

C)

D)

E)

Question 30

Which one of the following is the weakest acid?

A)HCN (Ka = 4.9 × 10^-10)
B)HClO (Ka = 3.0 × 10^-8)
C)HNO₂ (Ka = 4.5 × 10^-4)
D)HF (Ka = 6.8 × 10^-4)

Question 31

Which of the following is a weak acid?

A)HNO₃
B)H₃PO₄
C)NH₃
D)HCl
E)OH^-

Question 32

Write a balanced equation for the transfer of a proton between dihydrogen phosphate ion and the hydroxide ion.Identify the conjugate acid-base pairs and determine which side of the reaction is favored.

Question 33

What is the conjugate base of water?

A)H₂O(l)
B)H₃O⁺(aq)
C)OH^-(aq)
D)H⁺(aq)
E)O₂^-(aq)

Question 34

If the concentration of OH^- in an aqueous solution is 1.4 × 10^-7 M,the concentration of H₃O⁺ is

A)7.1 × 10⁺⁶ M.
B)1.0 × 10^-7 M.
C)1.4 × 10^-7 M.
D)7.1 × 10^-8 M.
E)1.3 × 10^-8 M.

Question 35

Explain the term "amphoteric." Use the hydrogen carbonate ion,HCO₃^- to illustrate amphoteric behavior.

Question 36

Which statement is correct for pure water?

A)Pure water contains equal amounts of hydroxide,[OH^-],and hydronium,[H₃O⁺],ions.
B)Pure water contains larger amounts of hydroxide,[OH^-],ions than hydronium,[H₃O⁺],ions.
C)Pure water contains larger amounts of hydronium,[H₃O⁺],ions than hydroxide,[OH^-],ions.
D)Pure water is an electrolyte.
E)Pure water contains no ions.

Question 37

Which one of the following weak acids is the strongest?

A)HCN (Ka = 4.9 × 10^-10)
B)HClO (Ka = 3.0 × 10^-8)
C)HNO₂ (Ka = 4.5 × 10^-4)
D)HF (Ka = 6.8 × 10^-4)

Question 38

Which of the following is a strong acid?

A)HNO₃
B)H₃PO₄
C)NH₄⁺
D)HCO₃^-
E)H₂O

Question 39

Write a balanced equation for the transfer of a proton between the bicarbonate ion and the hydronium ion.Identify the conjugate acid-base pairs and determine which side of the reaction is favored.

Question 40

Water and HSO₄^- can either accept protons or donate protons.Such substances are said to be

A)amphoteric.
B)conjugate.
C)diprotic.
D)monoprotic.
E)triprotic.

Question 41

Calculate the hydrogen ion concentration in a solution with pH = 6.35.

A)7.65 M
B)6.35 M
C)4.5 × 10^-7 M
D)0.80 M
E)2.2 × 10^-8 M

Question 42

Which example is not acidic?

A)orange juice
B)soil for azaleas with pH of 4.8
C)a solution of NH₄NO₃ with pH < 7.00
D)lake water that turns blue litmus to red
E)a solution in which [H₃O⁺] = 1.00 × 10^-7

Question 43

Which of the following statements is correct?

A)In an acidic solution,[H₃O⁺] < 10^-7;[OH^-] < 10^-7.
B)In an acidic solution,[H₃O⁺] > 10^-7;[OH^-] > 10^-7.
C)In an acidic solution,[H₃O⁺] > 10^-7;[OH^-] < 10^-7.
D)In an acidic solution,[H₃O⁺] < 10^-7;[OH^-] > 10^-7.
E)In an acidic solution,[H₃O⁺] > 10^-7;[OH^-] = 10^-7.

Question 44

Which of the following pH's corresponds to a weakly acidic solution?

A)5.3
B)1.4
C)7.8
D)9.2
E)11.5

Question 45

Which of the following pH's corresponds to a strongly basic solution?

A)11.5
B)2.7
C)6.9
D)7.4
E)4.3

Question 46

What is the pH of a solution in which [H₃O⁺] = 3.8 × 10^-8 M?

A)7.42
B)6.58
C)3.80
D)1.0 × 10^-8
E)2.6 × 10^-7

Question 47

If the concentration of H₃O⁺ is 3.5 × 10^-3 M,the concentration of OH^- is ________ M.

A)2.9 × 10^-12
B)1.0 × 10^-12
C)1.0 × 10^-7
D)3.5 × 10^-11
E)10.5 × 10^-3

Question 48

Which of the following pH's corresponds to a neutral solution?

A)7.0
B)1.8
C)6.2
D)8.5
E)14.0

Question 49

What is the value of [H₃O⁺] in a solution with pH = 10.82?

A)6.6 × 10^-4 M
B)1.5 × 10^-11 M
C)1.03 M
D)10.82 M
E)3.18 M

Question 50

An increase in solution pH corresponds to

A)an increase in hydronium ion concentration.
B)a decrease in hydronium ion concentration.
C)no change in hydronium ion concentration.
D)a decrease in hydroxide ion concentration.

Question 51

In an aqueous solution that is basic,[H₃O⁺] is ________ than 1.0 × 10^-7 and ________ than [OH^-].

A)greater;less
B)less;greater
C)greater;greater
D)less;less
E)none of the above

Question 52

If the concentration of OH^- is 1 × 10^-2 M,the concentration of H₃O⁺ is ________ M.

A)1 × 10⁰
B)1 × 10^-2
C)1 × 10^-7
D)1 × 10^-12
E)1 × 10^-14

Question 53

If the concentration of H₃O⁺ in an aqueous solution is 7.6 × 10^-9 M,the concentration of OH^- is

A)7.6 × 10^-23 M.
B)1.3 × 10⁺⁸ M.
C)6.4 × 10^-5 M.
D)1.3 × 10^-6 M.
E)7.6 × 10^-9 M.

Question 54

The pH of a cup of coffee is measured as 5.45.Express this measurement as [H⁺],using the correct number of significant figures.

A)3.548 × 10^-6 M
B)3.55 × 10^-6 M
C)3.6 × 10^-6 M
D)4 × 10^-6 M
E)2.82 × 10⁵ M

Question 55

Which solution is basic?

A)[H₃O⁺] = 1.0 × 10^-4
B)[H₃O⁺] = 1.0 × 10^-7
C)[H₃O⁺] = 1.0 × 10^-10
D)[OH^-] = 1.0 × 10^-7
E)[OH^-] = 1.0 × 10^-10

Question 56

In an aqueous solution that is acidic,[H₃O⁺] is ________ than 1.0 × 10^-7 and ________ than [OH^-].

A)greater;less
B)less;greater
C)greater;greater
D)less;less
E)none of the above

Question 57

Which example is not basic?

A)shampoo
B)vinegar
C)window cleaner
D)limewater
E)Mg(OH)₂,used in remedies for upset stomach

Question 58

What is the pH of a solution in which [H₃O⁺] = 4.1 × 10^-2 M?

A)12.61
B)1.39
C)1.10
D)12.90
E)4.10

Question 59

What is the hydrogen ion concentration in a solution with pH = 2.34?

A)4.6 × 10^-3 M
B)2.3 × 10^-3 M
C)2.2 × 10^-12 M
D)1.2 × 10¹ M
E)4.3 × 10^-12 M

Question 60

The pH of a solution with [H₃O⁺] = 5.9 × 10^-3 M,to the correct number of significant figures,is

A)5.9 × 10^-3.
B)2.2.
C)2.23.
D)1.01.
E)2.229.

Question 61

Which of the following solutions is a buffer?

A)a solution of acetic acid and sodium acetate
B)a solution of acetic acid and sodium sulfate
C)a solution of hydrochloric acid and sodium sulfate
D)a solution of hydrochloric acid and sodium acetate
E)a solution of sulfuric acid and sodium sulfate

Question 62

The normality of a solution prepared by dissolving 25.0 g of Ca(OH)₂ in water to make 250.mL solution is ________ N.

A)2.70
B)1.35
C)0.675
D)3.51
E)1.75

Question 63

The normality of a solution prepared by dissolving 50.0 g of Ca(OH)₂ in water to make 250.mL solution is ________ N.

A)1.35
B)2.70
C)3.51
D)5.40
E)7.02

Question 64

Which compound produces a basic solution when dissolved in water?

A)NH₄Cl
B)NaF
C)KClO₄
D)KCl
E)Ca(NO₃)₂

Question 65

What is the normality of a solution prepared by dissolving 75.0 g citric acid,a triprotic acid with molar mass of 192.14 g,in water to make 250.mL solution?

A)0.173 N
B)0.0576 N
C)0.293 N
D)4.68 N
E)1.56 N

Question 66

The pH of a 250.mL sample of a buffer solution is 9.85.If 1.0 mL of 6 M HCl is added,the pH of the resulting mixture is closest to

A)0.00.
B)1.65.
C)7.00.
D)9.70.
E)10.00.

Question 67

What is the normality of a solution containing 49 g of H₂SO₄ in enough water to make 400 mL of solution?

A)2.5 N
B)5.0 N
C)1.0 N
D)10 N
E)0.20 N

Question 68

Which substance produces carbon dioxide and water upon reaction with an acid?

A)NaCH₃CO₂
B)NH₄NO₃
C)MgCO₃
D)H₂C₂O₄
E)C₈H₁₈

Question 69

What is the normality of a solution prepared by dissolving 37.5 g citric acid,a triprotic acid with molar mass of 192.14 g,in water to make 250.mL solution?

A)2.34 N
B)0.780 N
C)0.147 N
D)0.0865 N
E)0.288 N

Question 70

Write the balanced chemical equation for a reaction between sodium bicarbonate and hydrochloric acid.

Question 71

Write the balanced chemical reaction between methyl amine (CH₃NH₂)and hydrobromic acid (HBr).

Question 72

To prepare a buffer using sodium phosphate,which of the following would also be needed?

A)hydrochloric acid
B)ammonium hydroxide
C)ammonium phosphate
D)phosphoric acid
E)sodium hydroxide

Question 73

Which of the following compounds is a salt?

A)HBr
B)KNO₃
C)H₂SO₄
D)NaOH
E)C₆H₁₂O₆

Question 74

What is the normality of a solution containing 100.g HNO₃ in 500.mL of solution?

A)1.26 N
B)1.59 N
C)3.17 N
D)0.500 N
E)0.630 N

Question 75

Which compound produces an acidic solution when dissolved in water?

A)NH₄Cl
B)NaF
C)K₂SO₄
D)KCl
E)Ca(NO₃)₂

Question 76

The [OH^-] and the pH of 0.035 M KOH at 25°C are,respectively,

A)0.035 M and +1.46.
B)0.035 M and -1.46.
C)2.9 × 10^-13 M and -12.54.
D)0.035 and +12.54.
E)2.9 × 10^-13 M and +12.54.

Question 77

Of the following four substances,which would form a basic solution when dissolved in water:
NH₄Cl Cu(NO₃)₂ K₂CO₃ NaF

A)NH₄Cl,Cu(NO₃)₂
B)K₂CO₃,NH₄Cl
C)NaF,K₂CO₃
D)NaF only
E)none of them

Question 78

All of the statements regarding equivalents of acids and bases are true except

A)equivalents are the same as moles.
B)equivalents of acid are based on the number of hydrogen ions produced per formula unit of acid.
C)equivalents are used to determine normality of solutions.
D)the equivalent weight of a base is the weight that produces one mole of hydroxide ions.
E)one equivalent of any acid will neutralize one equivalent of any base.

Question 79

Which of the following compounds is a salt?

A)CH₃CO₂H
B)NH₃
C)NH₄NO₃
D)Al(OH)₃
E)C₆H₆

Question 80

A buffer solution

A)is a salt solution.
B)maintains pH at 7.00.
C)is a strong base.
D)neutralizes only acids.
E)closely maintains its original pH.