Chemistry Chapter 16 A certain acid, HA, has a Ka given by

71) What is the pH of an aqueous solution labeled “0.10 M phosphoric acid”?

[Ka1 = 7.1 × 10-3; Ka2 = 6.3 × 10-8; Ka3 = 4.2 × 10–13]

A) 5.7

B) 4.3

C) 3.1

D) 2.3

E) 1.6

72) What is the [H2PO4–] of an aqueous solution labeled “0.10 M phosphoric acid“?

[Ka1 = 7.1 × 10-3; Ka2 = 6.3 × 10-8; Ka3 = 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

73) What is the [H2AsO4–] for an aqueous solution labeled “0.10 M arsenic acid (H3AsO4)”?

[Ka1 = 6 × 10-3, Ka2 = 1 × 10-7, Ka3 = 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

74) 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

75) 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

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

77) 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

78) A certain acid, HA, has a Ka given by:

HA + H2O ⇌ H3O+ + A– Ka = 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

79) 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

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

A) 10.0

B) 5.3

C) 11.0

D) 8.7

E) 3.0

81) What is the pH of a 0.120 M aqueous solution of the sodium salt of acetylsalicylic acid (aspirin)?

Ka (aspirin) = 3.3 × 10–4

A) 7.0

B) 11.8

C) 2.2

D) 5.7

E) 8.3

82) What is the pH of a 0.240 M aqueous solution of potassium cyanide? Ka (HCN) = 6.2 × 10–10

A) 11.3

B) 2.7

C) 4.9

D) 9.1

E) 9.4

83) Determine the pH of 263 ml of an aqueous solution which has [NH4I] = 0.300 M. Kb = 1.74 × 10-5 for

NH3(aq).

A) 2.6

B) 11.4

C) 4.9

D) 9.1

E) 4.6

84) What is the pH of a 0.253 M aqueous solution of ammonium chloride? Kb (NH3) = 1.2 × 10–5

A) 2.7

B) 4.8

C) 9.2

D) 11.3

E) 9.9

85) What is the pH of a 0.375 M aqueous solution of methylammonium chloride? Kb (CH3NH2) = 4.2 ×

10–4

A) 12.1

B) 1.9

C) 5.5

D) 8.5

E) 11.0

86) What is the pH of a 0.175 M aqueous solution of potassium benzoate? Ka (benzoic acid) = 6.3 × 10-5

A) 9.10

B) 3.44

C) 10.56

D) 5.28

E) 8.72

87) What is the pH of a 0.475 M aqueous solution of sodium nitrite? Ka (nitrous acid) = 7.2 × 10-4

A) 8.58

B) 8.41

C) 12.27

D) 5.42

E) 5.59

88) What is the pH of a 0.235 M aqueous solution of potassium fluoride? Ka (HF) = 6.6 × 10-4

A) 8.28

B) 11.45

C) 8.59

D) 5.41

E) 5.72

89) What is the pH of a 0.563 M aqueous solution of ammonium bromide? Kb (NH3) = 1.8 × 10-5

A) 2.50

B) 11.50

C) 4.75

D) 4.63

E) 9.25

90) What is the pH of a 0.361 M aqueous solution of pyridinium bromide? Kb (pyridine) = 1.5 × 10-9

A) 8.38

B) 5.62

C) 4.63

D) 2.81

E) 11.19

91) What is the pH of a 0.563 M aqueous solution of ethylammonium bromide? Kb (ethylammonia) = 4.3

× 10-4

A) 8.58

B) 1.79

C) 8.68

D) 5.32

E) 5.44

92) What is the indication of the relative acid strengths of the following acids?

CH3CH2CHClCOOH CH3CHClCH2COOH CH2ClCH2CH2COOH

A) CH3CHClCH2COOH > CH2ClCH2CH2COOH > CH3CH2CHClCOOH

B) CH2ClCH2CH2COOH > CH3CH2CHClCOOH > CH3CHClCH2COOH

C) CH2ClCH2CH2COOH > CH3CHClCH2COOH > CH3CH2CHClCOOH

D) CH3CH2CHClCOOH > CH3CHClCH2COOH > CH2ClCH2CH2COOH

E) CH3CH2CHClCOOH > CH2ClCH2CH2COOH > CH3CHClCH2COOH

93) List the following acids in order of increasing strength:

HClO2 HClO3 HClO4

A) HClO2 < HClO4 < HClO3

B) HClO4 < HClO3 < HClO2

C) HClO4 < HClO2 < HClO3

D) HClO3 < HClO2 < HClO4

E) HClO2 < HClO3 < HClO4

94) List the following acids in order of increasing strength:

HBrO HIO HClO

A) HIO < HClO < HBrO

B) HClO < HIO < HBrO

C) HBrO < HIO < HClO

D) HIO < HBrO < HClO

E) HClO< HBrO < HIO

95) List the following acids in order of increasing strength:

H2SO4 H2SeO4 H2TeO4

A) H2SeO4 < H2TeO4 < H2SO4

B) H2SeO4 < H2SO4 < H2TeO4

C) H2SO4 < H2TeO4 < H2SeO4

D) H2SO4 < H2SeO4 < H2TeO4

E) H2TeO4 < H2SeO4 < H2SO4

96) List the following acids in order of increasing strength:

H3PO4 H2SO4 HClO4

A) HClO4 < H3PO4 < H2SO4

B) H2SO4 < HClO4 < H3PO4

C) H2SO4 < H3PO4 < HClO4

D) H3PO4 < H2SO4 < HClO4

E) HClO4 < H2SO4 < H3PO4

97) What is the indication of the relative base strengths of the following bases?

CH3NH2 CHBr2NH2 CH2BrNH2

A) CH2BrNH2 > CHBr2NH2 > CH3NH2

B) CHBr2NH2 > CH2BrNH2 > CH3NH2

C) CHBr2NH2 > CH3NH2 > CH2BrNH2

D) CH2BrNH2 > CH3NH2 > CHBr2NH2

E) CH3NH2 > CH2BrNH2 > CHBr2NH2

98) CO2 acts as an acid in the reaction CaO(s) + CO2 ⇌ CaCO3(s) because it ________.

A) turns blue litmus red

B) reacts with a metal

C) is a proton donor

D) is an electron-pair acceptor

E) is a gas containing a non-metal

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

A) CH3CO2H

B) NaOH

C) Na2CO3

D) CH3CH2OH

100) Which Bronsted-Lowry acid is not considered to be a strong acid in water?

A) HBr

B) HI

C) HIO4

D) HNO3

101) Calculate the hydronium ion concentration in an aqueous solution that contains 2.50 × 10–6 mol L–1

in hydroxide ion.

A) 4.00 × 10–7 mol L-1

B) 4.00 × 10–8 mol L-1

C) 4.00 × 10–9 mol L-1

D) 5.00 × 10–9 mol L-1

102) Calculate the hydroxide ion concentration in an aqueous solution that contains 3.50 × 10–4 mol L-1 in

hydronium ion.

A) 2.86 × 10–3 mol L-1

B) 2.86 × 10–10 mol L-1

C) 2.86 × 10–11 mol L-1

D) 3.50 × 10–11 mol L-1

103) A solution with a hydrogen ion concentration of 3.25 × 10–6 mol L-1 is ________ and has a hydroxide

ion concentration of ________.

A) acidic, 3.08 × 10–8 mol L-1

B) acidic, 3.08 × 10–9 mol L-1

C) basic, 3.08 × 10–8 mol L-1

D) basic, 3.08 × 10–9 mol L–1

104) A solution with a hydroxide ion concentration of 4.15 × 10–6 mol L-1 is ________ and has a hydrogen

ion concentration of ________.

A) acidic, 2.41 × 10–8 mol L-1

B) acidic, 2.41 × 10–9 mol L-1

C) basic, 2.41 × 10–8 mol L-1

D) basic, 2.41 × 10–9 mol L–1

105) Calculate the pH for an aqueous solution of acetic acid that contains 5.15 × 10-3 mol L–1 hydronium

ion.

A) 1.94 × 10-12

B) 5.15 × 10–3

C) 2.288

D) 11.712

106) Calculate the pH for an aqueous solution of pyridine that contains 4.15 × 10-4 mol L-1 hydroxide ion.

A) 2.41 × 10–11

B) 4.15 × 10–4

C) 3.382

D) 10.618

107) What is the hydroxide ion concentration and the pH for a hydrochloric acid solution that has a

hydronium ion concentration of

A) 6.7 × 10–12 mol L-1, 2.82

B) 6.7 × 10–12 mol L-1, 11.18

C) 6.7 × 10–13 mol L-1, 1.82

D) 6.7 × 10–13 mol L-1, 12.17

108) What is the hydronium ion concentration and the pH for an aqueous solution of NH3 that has a

hydroxide ion concentration of

A) 4.44 × 10–12 mol L-1 and 2.648

B) 4.44 × 10–12 mol L-1 and 11.352

C) 4.44 × 10–13 mol L-1 and 1.648

D) 4.44 × 10–13 mol L-1 and 12.352

109) What is the hydronium ion concentration of an acid rain sample that has a pH of 3.35?

A) 2.2 × 10–11 mol L-1

B) 4.5 × 10-4 mol L-1

C) 3.35 mol L-1

D) 10.65 mol L-1

110) What is the hydroxide ion concentration of a lye solution that has a pH of 9.20?

A) 6.3 × 10–10 mol L-1

B) 1.6 × 10–5 mol L-1

C) 4.8 mol L-1

D) 9.2 mol L-1

111) What is the pH of a 0.020 mol L-1 HClO4 solution?

A) 0.020

B) 0.040

C) 1.70

D) 12.30

112) An aqueous solution at 25.0 °C contains [ ] = 0.085 mol L-1. What is the pH of the solution?

A) 1.07

B) -1.07

C) 13.0

D) 0.0850

E) 1.20 ×

113) The pH of an aqueous solution at 25.0 °C is 10.55. What is the molarity of in this solution?

A) 2.8 × 10–11

B) 3.5 × 10-4

C) 3.3

D) 1.1 × 10–13

E) 3.5 × 1010

114) Calculate the molarity of hydroxide ion in an aqueous solution that has a pOH of 5.00.

A) 1.0 × 10-5

B) 9.00

C) 1.0 × 10-9

D) 5.0 ×

E) 9.0 × 10–14

115) What is the hydronium ion concentration of a 0.500 mol L-1 aqueous acetic acid solution with Ka =

1.8 × 10-5? The equation for the dissociation of acetic acid is below:

A) 3.0 × 10-2 mol L-1

B) 4.2 × 10-2 mol L-1

C) 3.0 × 10-3 mol L-1

D) 4.2 × 10-3 mol L-1

116) What is the hydronium ion concentration of a 0.150 mol L-1 aqueous hypochlorous acid solution

with The equation for the dissociation of hypochlorous acid is below:

A) 1.9 × 10–4 mol L-1

B) 7.2 × 10–4 mol L-1

C) 2.8 × 10–5 mol L-1

D) 7.2 × 10–5 mol L-1

117) The acid-dissociation constant at 25.0 °C for hypochlorous acid (HClO) is 3.0 × . At equilibrium,

the molarity of in a 0.010 mol L-1 aqueous solution of HClO is:

A) 1.7 ×

B) 0.010

C) 5.8 ×

D) 4.76

E) 2.00

118) Calculate the pH of a 0.800 mol L-1 aqueous NaCH3CO2 solution. Ka for acetic acid, CH3CO2H, is

A) 2.42

B) 4.68

C) 9.32

D) 11.58

119) Calculate the pH of a 1.60 mol L-1 aqueous KBrO solution. Ka for hypobromous acid, HBrO, is

A) 2.55

B) 4.25

C) 9.75

D) 11.45

120) A 7.0 × 10-3 mol L-1 aqueous solution of at 25.0 °C has a pH of:

A) 12.15

B) 1.85

C) 1.4 × 10-2

D) 7.1 × 10–13

E) 11.85

121) What is the pH of a 0.040 mol L-1 aqueous Ba(OH)2 solution?

A) 1.10

B) 1.40

C) 12.60

D) 12.90

122) What is the pH of a 0.500 mol L-1 NH3 aqueous solution that has Kb = 1.8 × 10-5? The equation for

the dissociation of NH3 is below:

A) 2.22

B) 2.52

C) 11.48

D) 10.48

123) What is the pH of a 0.30 mol L-1 pyridine solution that has Kb = 1.9 × 10-9? The equation for the

dissociation of pyridine is below:

A) 4.62

B) 8.72

C) 9.38

D) 10.38

124) Determine the ammonia concentration of an aqueous solution that has a pH of 11.00. The equation

for the dissociation of NH3 (Kb = 1.8 × 10-5) is below:

A) 3.0 mol L-1

B) 0.056 mol L-1

C) 1.8 × 10–2 mol L-1

D) 1.0 × 10-3 mol L-1

125) The acid-dissociation constant of hydrocyanic acid (HCN) at 25.0 °C is 4.9 × . What is the pH of

an aqueous solution of 0.080 mol L-1 sodium cyanide (NaCN)?

A) 11.11

B) 2.89

C) 1.3 × 10-3

D) 7.8 × 10–12

E) 3.9 × 10–11

126) Calculate the pH of a 1.60 mol L-1 CH3NH3Cl solution. Kb for methylamine, CH3NH2, is

A) 1.61

B) 5.18

C) 8.82

D) 12.39

127) The base-dissociation constant of ethylamine ( ) is 6.4 × at 25.0 °C. The [ ] in a

aqueous solution of ethylamine is ________ mol L-1.

A) 3.5 ×

B) 2.9 ×

C) 3.1 ×

D) 3.2 ×

E) 11.46

128) Which one of the following salts, when dissolved in water, produces the solution with the highest

pH?

A) NaHCO3

B) KClO4

C) Na2CO3

D) CH3NH3Cl

129) If an equal number of moles of the weak acid HCN and the strong base KOH are added to water, is

the resulting solution acidic, basic, or neutral?

A) acidic

B) basic

C) neutral

D) Depends on the solution volume

130) Which one of the following salts, when dissolved in water, produces the solution with the highest

pH?

A) RbI

B) RbBr

C) RbCl

D) RbF

131) Which one of the following salts, when dissolved in water, produces the solution with a pH closest

to 7.00?

A) CsCl

B) CaO

C) KH CO3

D) NH4l

132) Which one of the following salts, when dissolved in water, produces the solution with the lowest

pH?

A) NaCl

B) KCl

C) MgCl2

D) AlCl3

133) Calculate the pH of a 0.080 mol L-1 aqueous carbonic acid solution, H2CO3(aq), that has the

stepwise dissociation constants Ka1 = 4.3 × 10-7 and Ka2 = 5.6 × 10–11.

A) 1.10

B) 3.73

C) 6.37

D) 10.25

134) Calculate the pH of a 0.60 mol L-1 aqueous H2SO3 solution that has the stepwise dissociation

constants Ka1 = 1.5 × 10-2 and

A) 1.02

B) 1.06

C) 1.82

D) 2.04

135) Calculate the concentration of bicarbonate ion, HCO3–, in a 0.010 mol L–1 aqueous H2CO3 solution

that has the stepwise dissociation constants Ka1 = 4.3 × 10-7 and Ka2 = 5.6 × 10–11.

A) 6.6 × 10–5 mol L-1

B) 4.3 × 10-7 mol L-1

C) 4.3 × 10–9 mol L-1

D) 5.6 × 10–11 mol L-1

136) What is the pH of a 0.40 mol L-1 aqueous H2Se solution that has the stepwise dissociation constants

Ka1 = 1.3 × 10-4 and

A) 2.14

B) 3.89

C) 4.28

D) 5.57

34

137) What is the selenide ion concentration [Se2-] for a 0.100 mol L-1 aqueous H2Se solution that has the

stepwise dissociation constants of and

A) 3.6 × 10-3 mol L-1

B) 1.3 × 10-4 mol L-1

C) 1.3 × 10-5 mol L-1

D) 1.0 × 10–11 mol L-1