Question 1

An aqueous solution contains 0.050 M of methylamine. The concentration of hydroxide ion in this solution is __________ M. Kb for methylamine is 4.4 × 10-4.

Accepted Answer

A) 0.050 
B) 2.2 × 10-5 
C) 2.9 × 10-3 
D) 4.5 × 10-3 
E) 4.7 × 10-3 
A) 0.050 
B) 2.2 × 10-5 
C) 2.9 × 10-3 
D) 4.5 × 10-3 
E) 4.7 × 10-3

Question 2

Of the following, which is the strongest acid?

Accepted Answer

A) HIO 
B) HIO4 
C) HIO2 
D) HIO3 
E) The acid strength of all of the above is the same. 
A) HIO 
B) HIO4 
C) HIO2 
D) HIO3 
E) The acid strength of all of the above is the same.

Question 3

In which of the following aqueous solutions does the weak acid exhibit the highest percentage ionization?

Accepted Answer

A) 0.01 M HC2H3O2 (Ka = 1.8 × 10-5) 
B) 0.01 M HNO2 (Ka = 4.5 × 10-4) 
C) 0.01 M HF (Ka = 6.8 × 10-4) 
D) 0.01 M HClO (Ka = 3.0 × 10-8) 
E) These will all exhibit the same percentage ionization. 
A) 0.01 M HC2H3O2 (Ka = 1.8 × 10-5) 
B) 0.01 M HNO2 (Ka = 4.5 × 10-4) 
C) 0.01 M HF (Ka = 6.8 × 10-4) 
D) 0.01 M HClO (Ka = 3.0 × 10-8) 
E) These will all exhibit the same percentage ionization.

Question 4

Which of the following ions will act as a weak base in water?

Accepted Answer

A) HS- 
B) F- 
C) NO2- 
D) ClO- 
E) All of the above will act as a weak base in water. 
A) HS- 
B) F- 
C) NO2- 
D) ClO- 
E) All of the above will act as a weak base in water.

Question 5

The acid-dissociation constant of hydrocyanic acid (HCN)at 25.0°C is 4.9 × 10-10. What is the pH of an aqueous solution of 0.080 M sodium cyanide (NaCN)?

Accepted Answer

A) 11.11 
B) 2.89 
C) 1.3 × 10-3 
D) 7.8 × 10-12 
E) 3.9 × 10-11 
A) 11.11 
B) 2.89 
C) 1.3 × 10-3 
D) 7.8 × 10-12 
E) 3.9 × 10-11

Question 6

The base-dissociation constant of ethylamine (C2H5NH2)is 6.4 × 10-4 at 25.0 °C. The [H+] in a 1.6 × 10-2 M solution of ethylamine is __________ M.

Accepted Answer

A) 3.5 × 10-12 
B) 2.9 × 10-3 
C) 3.1 × 10-12 
D) 3.2 × 10-3 
E) 11.46 
A) 3.5 × 10-12 
B) 2.9 × 10-3 
C) 3.1 × 10-12 
D) 3.2 × 10-3 
E) 11.46

Question 7

Ka for HX is 7.5 × 10-12. What is the pH of a 0.15 M aqueous solution of NaX?

Accepted Answer

A) 7.97 
B) 1.96 
C) 6.00 
D) 8.04 
E) 12.10 
A) 7.97 
B) 1.96 
C) 6.00 
D) 8.04 
E) 12.10

Question 8

Which of the following aqueous solutions has the highest [OH-]?

Accepted Answer

A) a solution with a pH of 3.0 
B) a 1 × 10-4 M solution of HNO3 
C) a solution with a pOH of 12.0 
D) pure water 
E) a 1 × 10-3 M solution of NH4Cl 
A) a solution with a pH of 3.0 
B) a 1 × 10-4 M solution of HNO3 
C) a solution with a pOH of 12.0 
D) pure water 
E) a 1 × 10-3 M solution of NH4Cl

Question 9

The magnitude of Kw indicates that __________.

Accepted Answer

A) water autoionizes very slowly 
B) water autoionizes very quickly 
C) water autoionizes only to a very small extent 
D) the autoionization of water is exothermic 
A) water autoionizes very slowly 
B) water autoionizes very quickly 
C) water autoionizes only to a very small extent 
D) the autoionization of water is exothermic

Question 10

An aqueous solution contains 0.050 M of methylamine. The concentration of H+ in this solution is __________ M. Kb for methylamine is 4.4 × 10-4.

Accepted Answer

A) 0.050 
B) 2.2 × 10-13 
C) 2.9 × 10-13 
D) 4.5 × 10-13 
E) none of the above 
A) 0.050 
B) 2.2 × 10-13 
C) 2.9 × 10-13 
D) 4.5 × 10-13 
E) none of the above

Question 11

The pH of a 0.60 M aqueous solution of formic acid, HCHO2, at 25.0°C is 1.98. What is the value of Ka for formic acid?

Accepted Answer

A) 2.0 × 10-5 
B) 1.8 × 10-4 
C) 6.0 × 10-5 
D) 3.5 × 10-4 
E) none of the above 
A) 2.0 × 10-5 
B) 1.8 × 10-4 
C) 6.0 × 10-5 
D) 3.5 × 10-4 
E) none of the above

Question 12

A BrØnsted-Lowry acid is defined as a substance that __________.

Accepted Answer

A) increases Ka when placed in H2O 
B) decreases [H+] when placed in H2O 
C) increases [OH-] when placed in H2O 
D) acts as a proton acceptor 
E) acts as a proton donor 
A) increases Ka when placed in H2O 
B) decreases [H+] when placed in H2O 
C) increases [OH-] when placed in H2O 
D) acts as a proton acceptor 
E) acts as a proton donor

Question 13

What is the pH of an aqueous solution at 25.0 °C in which [OH-] is 0.0050 M?

Accepted Answer

A) 5.30 
B) -11.70 
C) 2.30 
D) -2.30 
E) 11.70 
A) 5.30 
B) -11.70 
C) 2.30 
D) -2.30 
E) 11.70

Question 14

Using the data in the table, which of the conjugate acids below is the weakest acid?

Accepted Answer

A) NH4+ 
B) C5H5NH+ 
C) H3NOH+ 
D) NH3CH3+ 
E) NH4+ and NH3CH3+ 
A) NH4+ 
B) C5H5NH+ 
C) H3NOH+ 
D) NH3CH3+ 
E) NH4+ and NH3CH3+

Question 15

A BrØnsted-Lowry base is defined as a substance that __________.

Accepted Answer

A) increases [H+] when placed in H2O 
B) decreases [H+] when placed in H2O 
C) increases [OH-] when placed in H2O 
D) acts as a proton acceptor 
E) acts as a proton donor 
A) increases [H+] when placed in H2O 
B) decreases [H+] when placed in H2O 
C) increases [OH-] when placed in H2O 
D) acts as a proton acceptor 
E) acts as a proton donor

Question 16

The Ka of hypochlorous acid (HClO)is 3.00 × 10-8. What is the pH at 25.0°C of an aqueous solution that is 0.0200 M in HClO?

Accepted Answer

A) +2.45 
B) -2.45 
C) -9.22 
D) +9.22 
E) +4.61 
A) +2.45 
B) -2.45 
C) -9.22 
D) +9.22 
E) +4.61

Question 17

The hydride ion, H-, is a stronger base than the hydroxide ion, OH-. The product(s)of the reaction of hydride ion with water is/ are __________.

Accepted Answer

A) H3O+ (aq) 
B) OH- (aq)+ H2 (g) 
C) OH- (aq)+ 2H+ (aq) 
D) no reaction occurs 
E) H2O2 (aq) 
A) H3O+ (aq) 
B) OH- (aq)+ H2 (g) 
C) OH- (aq)+ 2H+ (aq) 
D) no reaction occurs 
E) H2O2 (aq)

Question 18

The conjugate acid of HSO4- is __________.

Accepted Answer

A) SO42- 
B) H2SO4 
C) HSO4+ 
D) H+ 
E) HSO3+ 
A) SO42- 
B) H2SO4 
C) HSO4+ 
D) H+ 
E) HSO3+

Question 19

A 0.15 M aqueous solution of the weak base B at 25.0°C has a pH of 8.88. The value of Kb for B is __________.

Accepted Answer

A) 3.0 × 10-5 
B) 1.8 × 10-5 
C) 3.9 × 10-10 
D) 1.3 × 10-10 
E) none of the above 
A) 3.0 × 10-5 
B) 1.8 × 10-5 
C) 3.9 × 10-10 
D) 1.3 × 10-10 
E) none of the above

Question 20

Of the following acids, __________ is a strong acid.

Accepted Answer

A) HNO2 
B) H2CO3 
C) HBrO3 
D) HClO 
E) HF 
A) HNO2 
B) H2CO3 
C) HBrO3 
D) HClO 
E) HF

Exam 16: Acid-Base Equilibria

An aqueous solution contains 0.050 M of methylamine. The concentration of hydroxide ion in this solution is __________ M. Kb for methylamine is 4.4 × 10-4.

Of the following, which is the strongest acid?

In which of the following aqueous solutions does the weak acid exhibit the highest percentage ionization?

Which of the following ions will act as a weak base in water?

The acid-dissociation constant of hydrocyanic acid (HCN)at 25.0°C is 4.9 × 10-10. What is the pH of an aqueous solution of 0.080 M sodium cyanide (NaCN)?

The base-dissociation constant of ethylamine (C2H5NH2)is 6.4 × 10-4 at 25.0 °C. The [H+] in a 1.6 × 10-2 M solution of ethylamine is __________ M.

Ka for HX is 7.5 × 10-12. What is the pH of a 0.15 M aqueous solution of NaX?

Which of the following aqueous solutions has the highest [OH-]?

The magnitude of Kw indicates that __________.

An aqueous solution contains 0.050 M of methylamine. The concentration of H+ in this solution is __________ M. Kb for methylamine is 4.4 × 10-4.

The pH of a 0.60 M aqueous solution of formic acid, HCHO2, at 25.0°C is 1.98. What is the value of Ka for formic acid?

A BrØnsted-Lowry acid is defined as a substance that __________.

What is the pH of an aqueous solution at 25.0 °C in which [OH-] is 0.0050 M?

Using the data in the table, which of the conjugate acids below is the weakest acid?

A BrØnsted-Lowry base is defined as a substance that __________.

The Ka of hypochlorous acid (HClO)is 3.00 × 10-8. What is the pH at 25.0°C of an aqueous solution that is 0.0200 M in HClO?

The hydride ion, H-, is a stronger base than the hydroxide ion, OH-. The product(s)of the reaction of hydride ion with water is/ are __________.

The conjugate acid of HSO4- is __________.

A 0.15 M aqueous solution of the weak base B at 25.0°C has a pH of 8.88. The value of Kb for B is __________.

Of the following acids, __________ is a strong acid.

Introduction: Matter and Measurement

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An aqueous solution contains 0.050 M of methylamine. The concentration of hydroxide ion in this solution is __________ M. K_b for methylamine is 4.4 × 10^-4.

The acid-dissociation constant of hydrocyanic acid (HCN)at 25.0°C is 4.9 × 10^-10. What is the pH of an aqueous solution of 0.080 M sodium cyanide (NaCN)?

The base-dissociation constant of ethylamine (C₂H₅NH₂)is 6.4 × 10^-4 at 25.0 °C. The [H⁺] in a 1.6 × 10^-2 M solution of ethylamine is __________ M.

K_a for HX is 7.5 × 10^-12. What is the pH of a 0.15 M aqueous solution of NaX?

Which of the following aqueous solutions has the highest [OH^-]?

The magnitude of K_w indicates that __________.

An aqueous solution contains 0.050 M of methylamine. The concentration of H⁺ in this solution is __________ M. K_b for methylamine is 4.4 × 10^-4.

The pH of a 0.60 M aqueous solution of formic acid, HCHO₂, at 25.0°C is 1.98. What is the value of K_a for formic acid?

What is the pH of an aqueous solution at 25.0 °C in which [OH^-] is 0.0050 M?

The K_a of hypochlorous acid (HClO)is 3.00 × 10^-⁸. What is the pH at 25.0°C of an aqueous solution that is 0.0200 M in HClO?

The hydride ion, H^-, is a stronger base than the hydroxide ion, OH^-. The product(s)of the reaction of hydride ion with water is/ are __________.

The conjugate acid of HSO₄^- is __________.

A 0.15 M aqueous solution of the weak base B at 25.0°C has a pH of 8.88. The value of K_b for B is __________.