Question 1

Ammonia is a __________.

Accepted Answer

A) weak acid 
B) strong base 
C) weak base 
D) strong acid 
E) salt 
A) weak acid 
B) strong base 
C) weak base 
D) strong acid 
E) salt

Question 2

Kb for NH3 is 1.8 × 10-5. What is the pH of a 0.45 M aqueous solution of NH4Cl at 25.0 °C?

Accepted Answer

A) 2.55 
B) 11.45 
C) 9.20 
D) 4.80 
E) 11.23 
A) 2.55 
B) 11.45 
C) 9.20 
D) 4.80 
E) 11.23

Question 3

What is the concentration (in M)of hydronium ions in a solution at 25.0 °C with pH = 4.153?

Accepted Answer

A) 4.15 
B) 9.85 
C) 1.42 × 10-10 
D) 7.03 × 10-5 
E) none of the above 
A) 4.15 
B) 9.85 
C) 1.42 × 10-10 
D) 7.03 × 10-5 
E) none of the above

Question 4

Using the data in the table, which of the conjugate bases below is the strongest base?

Accepted Answer

A) OAc- 
B) C7H5O2- 
C) NO2- 
D) F- 
E) OAc- and C7H5O2- 
A) OAc- 
B) C7H5O2- 
C) NO2- 
D) F- 
E) OAc- and C7H5O2-

Question 5

The molar concentration of hydronium ion in pure water at 25°C is __________.

Accepted Answer

A) 0.00 
B) 1.0 × 10-7 
C) 1.0 × 10-14 
D) 1.00 
E) 7.00 
A) 0.00 
B) 1.0 × 10-7 
C) 1.0 × 10-14 
D) 1.00 
E) 7.00

Question 6

Of the following substances, an aqueous solution of __________ will form basic solutions. NaHS Cu(NO3)2 KHCO3 NaF

Accepted Answer

A) NaHS, Cu(NO3)2 
B) KHCO3, NaHS 
C) NaF only 
D) NaF, KHCO3 
E) NaHS, KHCO3 and NaF 
A) NaHS, Cu(NO3)2 
B) KHCO3, NaHS 
C) NaF only 
D) NaF, KHCO3 
E) NaHS, KHCO3 and NaF

Question 7

Calculate the concentration (in M)of hydroxide ions in a solution at 25.0°C with a pOH of 4.223.

Accepted Answer

A) 5.98 × 10-5 
B) 1.67 × 10-10 
C) 1.67 × 104 
D) 5.99 × 10-19 
E) 1.00 × 10-7 
A) 5.98 × 10-5 
B) 1.67 × 10-10 
C) 1.67 × 104 
D) 5.99 × 10-19 
E) 1.00 × 10-7

Question 8

Calculate the pH of a solution at 25.0 °C that contains 1.94 × 10-10 M hydronium ions.

Accepted Answer

A) 1.94 
B) 4.29 
C) 7.00 
D) 14.0 
E) 9.71 
A) 1.94 
B) 4.29 
C) 7.00 
D) 14.0 
E) 9.71

Question 9

The base-dissociation constant, Kb, for pyridine, C5H5N, is 1.4 × 10-9. The acid-dissociation constant, Ka, for the pyridinium ion, C5H5NH+, is __________.

Accepted Answer

A) 1.0 × 10-7 
B) 1.4 × 10-23 
C) 7.1 × 10-4 
D) 1.4 × 10-5 
E) 7.1 × 10-6 
A) 1.0 × 10-7 
B) 1.4 × 10-23 
C) 7.1 × 10-4 
D) 1.4 × 10-5 
E) 7.1 × 10-6

Question 10

Calculate the pOH of 0.716 M anilinium hydrochloride (C6H5NH3Cl)solution in water, given that Kb for aniline is 3.83 × 10-4.

Accepted Answer

A) 1.78 
B) 12.22 
C) 5.37 
D) 8.63 
E) 12.42 
A) 1.78 
B) 12.22 
C) 5.37 
D) 8.63 
E) 12.42

Question 11

Of the following substances, an aqueous solution of __________ will form basic solutions. NH4Cl Cu(NO3)2 K2CO3 NaF

Accepted Answer

A) NH4Cl, Cu(NO3)2 
B) K2CO3, NH4Cl 
C) NaF only 
D) NaF, K2CO3 
E) NH4Cl only 
A) NH4Cl, Cu(NO3)2 
B) K2CO3, NH4Cl 
C) NaF only 
D) NaF, K2CO3 
E) NH4Cl only

Question 12

The conjugate acid of CH3NH2 is __________.

Accepted Answer

A) CH3NH2 
B) CH3NH3+ 
C) CH3NH3+ 
D) CH3NH+ 
E) none of the above 
A) CH3NH2 
B) CH3NH3+ 
C) CH3NH3+ 
D) CH3NH+ 
E) none of the above

Question 13

The Ka of hydrazoic acid (HN3)is 1.9 × 10-5 at 25.0°C. What is the pH of a 0.40 M aqueous solution of HN3?

Accepted Answer

A) 0.40 
B) 2.16 
C) 5.23 
D) 2.56 
E) -3.46 
A) 0.40 
B) 2.16 
C) 5.23 
D) 2.56 
E) -3.46

Question 14

Which one of the following statements regarding Kw is false?

Accepted Answer

A) pKw is 14.00 at 25°C 
B) The value of Kw is always 1.0 × 10-14. 
C) Kw changes with temperature. 
D) The value of Kw shows that water is a weak acid. 
E) Kw is known as the ion product of water. 
A) pKw is 14.00 at 25°C 
B) The value of Kw is always 1.0 × 10-14. 
C) Kw changes with temperature. 
D) The value of Kw shows that water is a weak acid. 
E) Kw is known as the ion product of water.

Question 15

What is the pOH of an aqueous solution at 25.0 °C that contains 3.98 × 10-9 M hydroxide ion?

Accepted Answer

A) 8.40 
B) 5.60 
C) 9.00 
D) 3.98 
E) 7.00 
A) 8.40 
B) 5.60 
C) 9.00 
D) 3.98 
E) 7.00

Question 16

What is the pOH of an aqueous solution at 25.0°C in which [H+] is 0.0025 M?

Accepted Answer

A) 8.01 
B) 11.40 
C) -11.40 
D) -8.01 
E) none of the above 
A) 8.01 
B) 11.40 
C) -11.40 
D) -8.01 
E) none of the above

Question 17

Which solution below has the highest concentration of hydroxide ions?

Accepted Answer

A) pH = 3.21 
B) pH = 12.6 
C) pH = 7.93 
D) pH = 9.82 
E) pH = 7.00 
A) pH = 3.21 
B) pH = 12.6 
C) pH = 7.93 
D) pH = 9.82 
E) pH = 7.00

Question 18

The Ka for HCN is 4.9 × 10-10. What is the value of Kb for CN-?

Accepted Answer

A) 2.0 × 10-5 
B) 4.0 × 10-6 
C) 4.9 × 104 
D) 4.9 × 10-24 
E) 2.0 × 109 
A) 2.0 × 10-5 
B) 4.0 × 10-6 
C) 4.9 × 104 
D) 4.9 × 10-24 
E) 2.0 × 109

Question 19

What is the pOH of an aqueous solution at 25.0 °C in which [OH-] is 0.0040 M?

Accepted Answer

A) 11.60 
B) -2.40 
C) 2.40 
D) -11.60 
E) 5.52 
A) 11.60 
B) -2.40 
C) 2.40 
D) -11.60 
E) 5.52

Question 20

What is the pH of an aqueous solution at 25.0 °C that contains 3.98 × 10-9 M hydronium ion?

Accepted Answer

A) 8.400 
B) 5.600 
C) 9.000 
D) 3.980 
E) 7.000 
A) 8.400 
B) 5.600 
C) 9.000 
D) 3.980 
E) 7.000

Exam 16: Acid-Base Equilibria

Ammonia is a __________.

Kb for NH3 is 1.8 × 10-5. What is the pH of a 0.45 M aqueous solution of NH4Cl at 25.0 °C?

What is the concentration (in M)of hydronium ions in a solution at 25.0 °C with pH = 4.153?

Using the data in the table, which of the conjugate bases below is the strongest base?

The molar concentration of hydronium ion in pure water at 25°C is __________.

Of the following substances, an aqueous solution of __________ will form basic solutions. NaHS Cu(NO3)2 KHCO3 NaF

Calculate the concentration (in M)of hydroxide ions in a solution at 25.0°C with a pOH of 4.223.

Calculate the pH of a solution at 25.0 °C that contains 1.94 × 10-10 M hydronium ions.

The base-dissociation constant, Kb, for pyridine, C5H5N, is 1.4 × 10-9. The acid-dissociation constant, Ka, for the pyridinium ion, C5H5NH+, is __________.

Calculate the pOH of 0.716 M anilinium hydrochloride (C6H5NH3Cl)solution in water, given that Kb for aniline is 3.83 × 10-4.

Of the following substances, an aqueous solution of __________ will form basic solutions. NH4Cl Cu(NO3)2 K2CO3 NaF

The conjugate acid of CH3NH2 is __________.

The Ka of hydrazoic acid (HN3)is 1.9 × 10-5 at 25.0°C. What is the pH of a 0.40 M aqueous solution of HN3?

Which one of the following statements regarding Kw is false?

What is the pOH of an aqueous solution at 25.0 °C that contains 3.98 × 10-9 M hydroxide ion?

What is the pOH of an aqueous solution at 25.0°C in which [H+] is 0.0025 M?

Which solution below has the highest concentration of hydroxide ions?

The Ka for HCN is 4.9 × 10-10. What is the value of Kb for CN-?

What is the pOH of an aqueous solution at 25.0 °C in which [OH-] is 0.0040 M?

What is the pH of an aqueous solution at 25.0 °C that contains 3.98 × 10-9 M hydronium ion?

Introduction: Matter and Measurement

Atoms, Molecules, and Ions

Stoichiometry: Calculations With Chemical Formulas and Equations

Aqueous Reactions and Solution Stoichiometry

Thermochemistry

Electronic Structure of Atoms

Periodic Properties of the Elements

Basic Concepts of Chemical Bonding

Molecular Geometry and Bonding Theories

Gases

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Solids and Modern Materials

Properties of Solutions

Chemical Kinetics

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Additional Aspects of Aqueous Equilibria

Chemistry of the Environment

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Chemistry of the Nonmetals

Transition Metals and Coordination Chemistry

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Filters

K_b for NH₃is 1.8 × 10^-5. What is the pH of a 0.45 M aqueous solution of NH₄Cl at 25.0 °C?

Of the following substances, an aqueous solution of __________ will form basic solutions. NaHS Cu(NO₃)₂ KHCO₃ NaF

Calculate the pH of a solution at 25.0 °C that contains 1.94 × 10^-¹⁰ M hydronium ions.

The base-dissociation constant, K_b, for pyridine, C₅H₅N, is 1.4 × 10^-9. The acid-dissociation constant, K_a, for the pyridinium ion, C₅H₅NH⁺, is __________.

Calculate the pOH of 0.716 M anilinium hydrochloride (C₆H₅NH₃Cl)solution in water, given that K_b for aniline is 3.83 × 10^-4.

Of the following substances, an aqueous solution of __________ will form basic solutions. NH₄Cl Cu(NO₃)₂ K₂CO₃ NaF

The conjugate acid of CH₃NH₂ is __________.

The K_a of hydrazoic acid (HN₃)is 1.9 × 10^-5 at 25.0°C. What is the pH of a 0.40 M aqueous solution of HN₃?

Which one of the following statements regarding K_w is false?

What is the pOH of an aqueous solution at 25.0 °C that contains 3.98 × 10^-9 M hydroxide ion?

What is the pOH of an aqueous solution at 25.0°C in which [H⁺] is 0.0025 M?

The K_a for HCN is 4.9 × 10^-10. What is the value of K_b for CN^-?

What is the pOH of an aqueous solution at 25.0 °C in which [OH^-] is 0.0040 M?

What is the pH of an aqueous solution at 25.0 °C that contains 3.98 × 10^-9 M hydronium ion?