Deck 16: Acids and Bases

Question 1

According to the Arrhenius theory,a neutralization reaction involves the combination of an acid with a base to make only water.

Answer 1

False

Question 2

The first ionization step is approximately 100% for H₂SO₃.

Answer 2

False

Question 3

The term pH = -ln [H⁺].

Answer 3

False

Question 4

According to the Arrhenius theory,a neutralization reaction involves:

A)the combination of hydrogen ions and hydroxide ions to form water
B)the dissociation of a strong acid to hydrogen ions and an anion
C)the dissociation of a strong base into hydroxide ions and a cation
D)the addition of water to ammonia to make ammonium hydroxide
E)the combination of an acid with a base to make only water

Question 5

Br∅nsted and Lowry suggested that bases be defined as proton acceptors.

Question 6

Choose the Br∅nsted-Lowry acids and bases in the following equation:
HCO₃^- + OH^- ⇌ H₂O + CO₃^2-

A)acids HCO₃^-,H₂O bases OH^-,CO₃^2-
B)acids OH^-,CO₃^2- bases HCO₃^-,H₂O
C)acids H₂O,OH^- bases HCO₃^-,CO₃^2-
D)acids HCO₃^-,OH^- bases CO₃^2-,H₂O
E)acids H₂O,CO₃^2- bases HCO₃^-,OH^-

Question 7

Choose the Br∅nsted-Lowry acids and bases in the following equation:
HSO₄^- + C₂H₃O₂^- ⇌ HC₂H₃O₂ + SO₄^2-

A)acids HSO₄^-,SO₄^2- bases HC₂H₃O₂,C₂H₃O₂^-
B)acids HSO₄^-,HC₂H₃O₂ bases SO₄^2-,C₂H₃O₂^-
C)acids SO₄^2-,HC₂H₃O₂ bases HSO₄^-,C₂H₃O₂^-
D)acids SO₄^2-,C₂H₃O₂^- bases HSO₄^-,HC₂H₃O₂
E)acids HSO₄^-,C₂H₃O₂^- bases HC₂H₃O₂,SO₄^2-

Question 8

The definition of a neutralization reaction as a reaction in which an acid reacts with a base to produce water and a salt is inherent in:

A)only the Arrhenius theory
B)both the Arrhenius and the Br∅nsted-Lowry theories
C)only the Br∅nsted-Lowry theory
D)both the Br∅nsted-Lowry and the Lewis theories
E)only the Lewis theory

Question 9

H₂SO₄ is a weaker acid than H₂SO₃.

Question 10

When comparing binary acids of the elements in the same row of the periodic table,acid strength increases as the polarity of the element-hydrogen bond increases.

Question 11

Which of the following are Br∅nsted-Lowry acids?
I.CH₃COOH
II.[Cu(H₂O)₄]<sup>2+

III.</sup>H₂O
IV.CH₃NH<sub>2

V.</sub>H₃O⁺

A)I,IIand III
B)II,III,and IV
C)I,II,IIIand IV
D)I,II,III,and V
E)II,IIIand V

Question 12

Choose the Br∅nsted-Lowry acids and bases in the following equation:
HCN + OH^- ⇌ H₂O + CN^-

A)acids HCN,CN^- bases OH^-,H₂O
B)acids CN^-,OH^- bases HCN,H₂O
C)acids HCN,H₂O bases OH^-,CN^-
D)acids OH^-,H₂O bases CN^-,HCN
E)acids HCN,OH^- bases H₂O,CN^-

Question 13

HNO₃ is a strong acid.

Question 14

Choose the Br∅nsted-Lowry acids and bases in the following equation:
NH₄⁺ + OH^- ⇌ H₂O + NH₃

A)acids NH₄⁺,OH^- bases H₂O,NH₃
B)acids OH^-,H₂O bases NH₃,NH₄⁺
C)acids NH₄⁺,OH^- bases NH₄⁺,H₂O
D)acids NH₄⁺,H₂O bases OH^-,NH₃
E)acids NH₄⁺,NH₃ bases OH^-,H₂O

Question 15

In the equilibrium system described by:

Theory would designate:

A)PO₄^3- and H₂O as the bases
B)H₂O and OH^- as a conjugate pair
C)HPO₄^2- and OH^- as the acids
D)HPO₄^2- and H₂O as a conjugate pair
E)PO₄^3- as amphiprotic

Question 16

Amine bases are known as strong bases.

Question 17

According to the Arrhenius theory,a neutralization reaction involves the combination of hydrogen ions and hydroxide ions to form water.

Question 18

Proton acceptor is an abbreviated definition of:

A)Br∅nsted-Lowry base
B)Br∅nsted-Lowry acid
C)Lewis base
D)Lewis acid
E)Arrhenius acid

Question 19

Choose the Br∅nsted-Lowry acids and bases in the following equation:
H₂O + NH₂^- ⇌ NH₃ + OH^-

A)acids H₂O,OH^- bases NH₃,NH₂^-
B)acids NH₂^-,NH₃ bases H₂O,OH^-
C)acids H₂O,NH₂^- bases OH^-,NH₃
D)acids NH₃,NH₂^- bases OH^-,H₂O
E)acids H₂O,NH₃ bases NH₂^-,OH^-

Question 20

In the reaction BF₃ + NH₃ → F₃B:NH₃,BF₃ acts as a Br∅nsted acid.

Question 21

A saturated aqueous solution of calcium hydroxide has a pH of 12.25.What is the [Ca²⁺] in such a solution?

A)0.018
B)5.6 × 10^-13
C)2.3 × 10^-5
D)0.035
E)8.9 × 10^-3

Question 22

Which of the following is a logical inference from the fact that a 0.10 M solution of potassium acetate,KC₂H₃O₂,is less alkaline than a 0.10 M solution of potassium cyanide,KCN?

A)Hydrocyanic acid is a weaker acid than acetic acid.
B)Cyanides are less soluble than acetates.
C)Hydrocyanic acid is less soluble in water than acetic acid.
D)Acetic acid is a weaker acid than hydrocyanic acid.
E)0.10 M potassium acetate is more concentrated than 0.10 M potassium cyanide.

Question 23

A solution has pOH of -0.47.This means that:

A)the solution has a pH of 13.53
B)the solution has an [OH^-] = 0.34 M
C)the solution has an [OH^-] greater than 10.0 M
D)the solution has an [OH^-] = 2.95 M
E)The solution has an [H⁺] = 2.95 M

Question 24

A 0.214 M aqueous solution of a monoprotic base has a pH of 11.48.What is the ionization constant of this base?

A)1.4 × 10^-2
B)4.3 × 10^-5
C)1.5 × 10^-11
D)5.1 × 10^-23
E)2.0 × 10^-6

Question 25

A 0.505 g sample of a monoprotic base (mm = 45.09 g/mol)was dissolved in water to produce 100.0 mL of solution with a pH = 11.84.What is the ionization constant of this base?

A)4.3 × 10^-5
B)1.9 × 10^-23
C)4.3 × 10^-4
D)3.4 × 10^-1
E)1.3 × 10^-11

Question 26

At 25 °C,the pH of pure water is:

A)0
B)>0,<7
C)7
D)>7,<14
E)14

Question 27

A 0.632 M aqueous solution of a monoprotic base has a pH of 11.53.What is the ionization constant of this base?

A)1.8 × 10^-5
B)2.1 × 10^-3
C)1.6 × 10^-23
D)5.0 × 10^-12
E)5.3 × 10^-3

Question 28

pOH = 3.14 is equivalent to:

A)pH = 11
B)[H⁺] = 1.4 × 10^-10 M
C)[OH^-] = 7.2 × 10^-4 M
D)[H⁺} = 7.0 × 10^-4 M
E)[OH^-] = 3.14 × 10^-7 M

Question 29

0.653 g of a monoprotic acid (MW= 157 g/mol)is dissolved in water to produce 50.0 mL of a solution with pH = 2.13.Determine the ionization constant of the acid.

A)7.9 × 10^-3
B)8.9 × 10^-2
C)6.6 × 10^-4
D)3.9 × 10^-2
E)3.6 × 10^-6

Question 30

Choose the strongest acid.

A)HF
B)H₂CO₃
C)HCN
D)HC₂H₃O₂
E)HClO₄

Question 31

The pH of a solution of NH₄C₂H₃O₂ is approximately 7.The best explanation is:

A)This salt does not react with water.
B)Ammonium acetate is a weak electrolyte.
C)All salts of weak acids and weak bases are neutral.
D)Aqueous ammonia and acetic acid have approximately equal ionization constants.
E)The salt is a product of a strong acid and a strong base.

Question 32

0.272 g of a monoprotic acid (MW = 189 g/mol)is dissolved in water to produce 25.0 mL of a solution with pH = 4.93.Determine the ionization constant of the acid.

A)4.1 × 10^-8
B)1.4 × 10^-10
C)2.1 × 10^-4
D)2.8 × 10^-7
E)2.4 × 10^-9

Question 33

Which of the following is the strongest base?

A)Cl^-
B)ClO₄^-
C)F^-
D)NO₃^-
E)H₂O

Question 34

A 0.0925 g sample of a monoprotic base (mm = 17.03 g/mol)was dissolved in water to produce 100 mL of solution with a pH = 11.00.What is the ionization constant of this base?

A)1.8 × 10^-6
B)1.8 × 10^-11
C)1.8 × 10^-21
D)1.8 × 10^-5
E)1.1 × 10^-6

Question 35

For which of the following polyprotic acids is the first ionization step approximately 100%?

A)H₂S
B)H₂SO₃
C)H₂CO₃
D)H₂SO₄
E)H₃PO₄

Question 36

Choose the INCORRECT statement.The term pH:

A)refers to the "potential" of hydrogen ion
B)= -ln [H⁺]
C)= 14 - pOH
D)is more convenient than exponential notation
E)= -log [H₃O⁺]

Question 37

What is the [HPO₄^-2] of a solution labeled "0.10 M phosphoric acid"?
[K_a1 = 7.1 × 10^-3;K_a2 = 6.3 × 10^-8;K_a3 = 4.2 × 10^-13]

A)4.2 × 10^-13 M
B)6.3 × 10^-8 M
C)7.1 × 10^-3 M
D)1.6 × 10^-9 M
E)1.6 × 10^-16 M

Question 38

Consider the reaction:
HC₂H₃O₂ + H₂O ⇌ H₃O⁺ + C₂H₃O₂^-
Choose the pair of substances that are both bases in the reaction.

A)HC₂H₃O₂ and H₃O⁺
B)H₂O and C₂H₃O₂^-
C)H₂O and H₃O⁺
D)HC₂H₃O₂ and C₂H₃O₂^-
E)H₃O⁺ and HC₂H₃O₂

Question 39

What is the [AsO₄^3-] for a solution labeled "0.10 M arsenic acid (H₃AsO₄)"?
[K_a1 = 6 × 10^-3,K_a2 = 1 × 10^-7,K_a3 = 3 × 10^-12]

A)1 × 10^-7 M
B)1 × 10^-17 M
C)3 × 10^-12 M
D)3 × 10^-19 M
E)6 × 10^-10 M

Question 40

0.375 g of a monoprotic acid (MW = 245 g/mol)is dissolved in water to produce 25.0 mL of a solution with pH = 3.28.Determine the ionization constant of the acid.

A)8.56 × 10^-3
B)4.5 × 10^-6
C)7.4 × 10^-5
D)4.5 × 10^-3
E)2.3 × 10^-2

Question 41

In which of the following cases is water acting as a base under the Lewis definitions,but not under the Bronsted-Lowry definitions?

A)H₂O(l)+ HF(g)⇌ H₃O⁺(aq)+ F^-(aq)
B)H₂O(l)⁺ CN^-(aq)⇌ OH^-(aq)+ HCN(aq)
C)2 H₂O(l)+ Cu²⁺(aq)⇌ Cu(H₂O)₂²⁺(aq)
D)2 H₂O(l)+ PO₄^3-(aq)⇌ 2 OH^-(aq)+ H₂PO₄^-(aq)
E)2 H₂O(l)[electrolysis] ⇌ 2 H₂(g)+ O₂(g)

Question 42

In the following reversible reaction the Br∅nsted acids are ________.
HCO₃^-(aq)+ OH^-(aq)⇌ CO₃^2-(aq)+ H₂O

A)HCO₃^- and H₂O
B)HCO₃^- and CO₃^2-
C)OH^- and CO₃^2-
D)OH^- and H₂O
E)H₂O and CO₃^2-

Question 43

A 250.0 ml sample of gaseous hydrogen bromide,measured at 22.9 °C and 0.930 atm,was dissolved in sufficient pure water to form 250.0 ml of solution.What was the pH of that solution?

A)1.42
B)2.58
C)3.83
D)4.18
E)5.68

Question 44

What is the pH of a solution prepared by dissolving 0.140 g of potassium hydroxide in sufficient pure water to prepare 250.0 ml of solution?

A)2.000
B)6.000
C)10.000
D)12.000
E)14.000

Question 45

What would be the pH of a solution prepared by dissolving 14.4 g NaOH (MW = 40.0 g/mol)in enough water to make 1.05 L of solution?

A)13.54
B)0.46
C)13.58
D)13.66
E)7.00

Question 46

A saturated aqueous solution of calcium hydroxide is approximately 0.13% calcium hydroxide,by mass,and has a density of 1.02 g ml^-1.What is the pH of such a solution?

A)11.95
B)12.25
C)12.55
D)12.75
E)13.00

Question 47

Which of the following are Lewis bases?
I.BCl₃
II.H^-
III.H₂O
IV.NH₃
V.AlCl₃

A)II,IIIand IV
B)I,II,and III
C)III,IVand V
D)I,II,and V
E)I,II,and IV

Question 48

For NH₃,predict whether a 1 M aqueous solution is acidic,basic or neutral and why.

A)acidic because NH₃ is a strong acid
B)basic because NH₃ is a weak base
C)neutral because there is no hydrolysis
D)basic because NH₃ is the salt of a weak acid
E)acidic because NH₃ is the salt of a weak base

Question 49

Complete the following equation.List the conjugate acid base pairs.Put the base first in each pair.
HCl + NH₃ ⇌

A)Cl^- + NH₄⁺ (NH₃,NH₄⁺)(Cl^-,HCl)
B)Cl^- + NH₄⁺ (NH₃,HCl)(Cl^-,NH₄⁺)
C)H₂ + Cl^- + NH₂^- (NH₃,NH₂^-)(Cl^-,HCl)
D)H₂Cl⁺ + NH₂^- (NH₃,NH₂^-)(HCl,H₂Cl)
E)Cl^- + NH₄⁺ (NH₃,Cl^-)(NH₄⁺,HCl)

Question 50

Which species in the following reaction acts as a Lewis acid?
CuSO₄(s)+ 4 NH₃(aq)⇌ [Cu(NH₃)_4]²⁺(aq)+ SO₄^2-(aq)

A)SO₄^2-
B)Cu²⁺
C)[Cu(NH₃)_4]²⁺(aq)
D)NH₃
E)[Cu(NH₃)_4]²⁺(aq)and SO₄^2-

Question 51

The concept of an acid not limited to H⁺ or species containing one or more protons is inherent in:

A)only the Arrhenius theory
B)both the Arrhenius and the Br∅nsted-Lowry theories
C)only the Br∅nsted-Lowry theory
D)both the Br∅nsted-Lowry and the Lewis theories
E)only the Lewis theory

Question 52

Which of the following statements concerning aqueous solutions of salts is FALSE?

A)For any salt of a strong acid and a strong base,the pH will be about 7.
B)For any salt of a strong acid and a weak base,the pH will be <7.
C)For any salt of a weak acid and a strong base,the pH will be >7.
D)For any salt of a weak acid and a weak base,the pH will be about 7.
E)Salt solutions can have a pH of 7.

Question 53

If one mole of Ba(OH)₂ is added to enough water to make 10 liters of solution,the pH of the resulting solution is ________.

A)13.3
B)1.0
C)0.7
D)13.0
E)12.5

Question 54

Which indication of relative acid strengths is INCORRECT?

A)HCl > HF
B)HClO₂ > HClO
C)H₂SO₄ > H₂SO₃
D)H₂SO₃ > HNO₃
E)CH₃CO₂H > CH₃CH₂OH

Question 55

What is the [OH^-] of a solution prepared by dissolving 0.0912 g of hydrogen chloride in sufficient pure water to prepare 250.0 ml of solution?

A)1.00 × 10^-2 M
B)1.00 × 10^-8 M
C)1.00 × 10^-12 M
D)1.00 × 10^-4 M
E)1.0 M

Question 56

What is the [Cl^-] of a solution prepared by dissolving 0.1824 g of hydrogen chloride in sufficient pure water to prepare 500.0 ml of solution?

A)1.00 × 10^-2 M
B)1.00 × 10^-8 M
C)1.00 × 10^-12 M
D)1.00 × 10^-4 M
E)1.0 M

Question 57

For HI,predict whether the solution is acidic,basic or neutral and why.

A)acidic because HI is a strong acid
B)basic because HI is a weak base
C)neutral because there is no hydrolysis
D)basic because HI is the salt of a weak acid
E)acidic because HI is the salt of a weak base

Question 58

What is the pH of a 0.470 M aqueous solution of pyridine?
K_b = 1.5 × 10^-9

A)9.0
B)11.2
C)2.8
D)9.4
E)4.6

Question 59

What is the [K⁺] of a solution prepared by dissolving 0.140 g of potassium hydroxide in sufficient pure water to prepare 250.0 ml of solution?

A)10^-5 M
B)10^-8 M
C)10^-12 M
D)10^-4 M
E)10^-2 M

Question 60

In the reaction BF₃ + NH₃ ⇌ F₃B:NH₃,BF₃ acts as:

A)an Arrhenius base
B)a Lewis base
C)a Br∅nsted acid
D)a Lewis acid
E)an Arrhenius acid

Question 61

What is the [H₂AsO₄^-] for an aqueous solution labeled "0.10 M arsenic acid (H₃AsO₄)"?
[K_a1 = 6 × 10^-3,K_a2 = 1 × 10^-7,K_a3 = 3 × 10^-12]

A)1 × 10^-7 M
B)6 × 10^-3 M
C)0.02 M
D)0.08 M
E)6 × 10^-10 M

Question 62

For NH₄Cl,predict whether the aqueous solution is acidic,basic or neutral and why.

A)acidic because NH₄Cl is a strong acid
B)basic because NH₄Cl is a weak base
C)neutral because there is no hydrolysis
D)basic because NH₄Cl is the salt of a weak acid
E)acidic because NH₄Cl is the salt of a weak base

Question 63

What is the pH of a 0.052 M aqueous solution of sodium acetate? K_a (acetic acid)= 1.8 × 10^-5

A)10.0
B)5.3
C)11.0
D)8.7
E)3.0

Question 64

For NaC₂H₃O₂,predict whether the aqueous solution is acidic,basic or neutral and why.

A)acidic because NaC₂H₃O₂ is a strong acid
B)basic because NaC₂H₃O₂ is a weak base
C)neutral because there is no hydrolysis
D)basic because NaC₂H₃O₂ is the salt of a weak acid
E)acidic because NaC₂H₃O₂ is the salt of a weak base

Question 65

What is the pH of an aqueous solution labeled "0.10 M phosphoric acid"?
[K_a1 = 7.1 × 10^-3;K_a2 = 6.3 × 10^-8;K_a3 = 4.2 × 10^-13]

A)5.7
B)4.3
C)3.1
D)2.3
E)1.6

Question 66

What is the concentration of free sulfate ion in an aqueous solution labeled "3.6 M H₂SO₄"?
[K_a2 = 1.1 × 10^-2]

A)0.011 M
B)0.040 M
C)0.20 M
D)0.60 M
E)1.8 M

Question 67

What is the pH of a 0.250 M aqueous solution of formic acid?
K_a = 1.8 × 10^-4

A)11.8
B)2.2
C)0.60
D)5.4
E)8.6

Question 68

What is the pH for a solution labeled "0.10 M arsenic acid (H₃AsO₄)"?
[K_a1 = 6 × 10^-3,K_a2 = 1 × 10^-7,K_a3 = 3 × 10^-12]

A)1.6
B)4.0
C)6.3
D)1.0
E)3.2

Question 69

A certain acid,HA,has a K_a given by:
HA + H₂O ⇌ H₃O⁺ + A^- K_a = 6.80 × 10^-6
What is the pH of a 0.247 M aqueous solution of the acid's potassium salt,KA,which undergoes the hydrolysis reaction?
A^- + H₂O ⇌ OH^- + HA

A)4.72
B)9.28
C)4.11
D)9.89
E)9.44

Question 70

What is the pH of an aqueous solution labeled "0.50 M sodium fluoride" if the ionization constant of hydrofluoric acid is 6.0 × 10^-4?

A)10.8
B)8.5
C)7.1
D)6.9
E)5.5

Question 71

What is the pH of a 0.570 M aqueous solution of aniline?
K_b = 7.4 × 10^-10

A)11.4
B)2.6
C)9.8
D)4.7
E)9.3

Question 72

What is the pH of a 0.375 M aqueous solution of benzoic acid?
K_a = 6.3 × 10^-5

A)8.9
B)5.1
C)2.3
D)0.43
E)11.7

Question 73

What is the pH of a 0.380 M aqueous solution of ethylamine?
K_b = 4.3 × 10^-4

A)12.1
B)1.9
C)10.2
D)5.5
E)8.5

Question 74

The ionization constant for ammonia is 1.8 × 10^-5.What is the pH of an aqueous solution labeled 0.50 M ammonia?

A)7.30
B)9.12
C)10.26
D)11.48
E)12.52

Question 75

For NaCl,predict whether the aqueous solution is acidic,basic or neutral and why.

A)acidic because NaCl is a strong acid
B)basic because NaCl is a weak base
C)neutral because there is no hydrolysis
D)basic because NaCl is the salt of a weak acid
E)acidic because NaCl is the salt of a weak base

Question 76

For Na₂CO₃,predict whether the aqueous solution is acidic,basic or neutral and why.

A)acidic because Na₂CO₃ is a strong acid
B)basic because Na₂CO₃ is a weak base
C)neutral because there is no hydrolysis
D)basic because Na₂CO₃ is the salt of a weak acid
E)acidic because Na₂CO₃ is the salt of a weak base

Question 77

Hypochlorous acid (HOCl)has an ionization constant of 3.2 × 10^-8.What is its percent ionization in 1.0 M and 0.10 M solutions,respectively?

A)0.018% and 0.057%
B)0.032% and 0.0032%
C)0.57% and 0.18%
D)0.57% in both
E)0.32% in both

Question 78

The K_b value for methylamine is 4.2 × 10^-4.What is the pH of an aqueous solution for which the label reads "0.042 M CH₃NH₂"?

A)2.4
B)4.8
C)9.2
D)11.6
E)12.3

Question 79

What is the pH of a 0.530 M aqueous solution of hypochlorus acid?
K_a = 2.9 × 10^-8

A)10.6
B)3.4
C)10.1
D)3.9
E)0.28

Question 80

What is the [H₂PO₄^-] of an aqueous solution labeled "0.10 M phosphoric acid"?
[K_a1 = 7.1 × 10^-3;K_a2 = 6.3 × 10^-8;K_a3 = 4.2 × 10^-13]

A)0.023 M
B)6.3 × 10^-8 M
C)7.1 × 10^-3 M
D)4.2 × 10^-13 M
E)0.013 M