Question 1

Which of the following is the strongest acid?

Accepted Answer

A)  CH3COOH 
B)  HF 
C)  H3PO4 
D)  H2SO3 
E)  H2SO4 
A)  CH3COOH 
B)  HF 
C)  H3PO4 
D)  H2SO3 
E)  H2SO4

Question 2

Lactic acid has a pKa of 3.08. What is the approximate degree of dissociation of a 0.35 M solution of lactic acid?

Accepted Answer

A)  1.1% 
B)  2.2% 
C)  4.8% 
D)  14% 
E)  None of these choices are correct. 
A)  1.1% 
B)  2.2% 
C)  4.8% 
D)  14% 
E)  None of these choices are correct.

Question 3

Kw = 1.0 × 10-14, regardless of temperature.

Accepted Answer

A) True 
 B)False

Question 4

Hydrated metal ions in aqueous solution can act as Brønsted-Lowry acids.

Accepted Answer

A) True 
 B)False

Question 5

A 1.25 M solution of the weak acid HA is 9.2% dissociated. What is the pH of the solution?

Accepted Answer

A)  0.64 
B)  0.94 
C)  1.13 
D)  2.16 
E)  None of these choices are correct. 
A)  0.64 
B)  0.94 
C)  1.13 
D)  2.16 
E)  None of these choices are correct.

Question 6

Which of the following pairs has the stronger acid listed first?

Accepted Answer

A)  H2AsO3, H2AsO4 
B)  HI, HBr 
C)  HClO, HClO3 
D)  H2S, HCl 
E)  H2SO3, H2SO4 
A)  H2AsO3, H2AsO4 
B)  HI, HBr 
C)  HClO, HClO3 
D)  H2S, HCl 
E)  H2SO3, H2SO4

Question 7

Aqueous solutions of phosphoric acid and sodium nitrite are combined, and the following equilibrium is established. H3PO4(aq) + NO2(aq)   H2PO4(aq) + HNO2(aq)
The equilibrium constant Kc for this reaction is greater than one. Based on this information, which of the following statements is correct?

Accepted Answer

A)  Phosphoric acid is a weaker acid than nitrous acid. 
B)  Nitrous acid is a weaker acid than water. 
C)  The nitrite anion is a weaker base than the dihydrogen phosphate anion. 
D)  The dihydrogen phosphate anion is a stronger acid than nitrous acid. 
E)  Phosphoric acid is a stronger acid than nitrous acid. 
A)  Phosphoric acid is a weaker acid than nitrous acid. 
B)  Nitrous acid is a weaker acid than water. 
C)  The nitrite anion is a weaker base than the dihydrogen phosphate anion. 
D)  The dihydrogen phosphate anion is a stronger acid than nitrous acid. 
E)  Phosphoric acid is a stronger acid than nitrous acid.

Question 8

What is the pH of a 0.20 M HCl solution?

Accepted Answer

A)  < 0 
B)  0.70 
C)  1.61 
D)  12.39 
E)  13.30 
A)  < 0 
B)  0.70 
C)  1.61 
D)  12.39 
E)  13.30

Question 9

What is the pH of a 0.75 M HNO3 solution?

Accepted Answer

A)  0.12 
B)  0.29 
C)  0.63 
D)  0.82 
E)  > 1.0 
A)  0.12 
B)  0.29 
C)  0.63 
D)  0.82 
E)  > 1.0

Question 10

Which one of the following pairs is not a conjugate acid-base pair?

Accepted Answer

A)  H2O/OH- 
B)  H2O2/HO2- 
C)  OH-/O2- 
D)  H2PO4-/HPO42- 
E)  HCl/H+ 
A)  H2O/OH- 
B)  H2O2/HO2- 
C)  OH-/O2- 
D)  H2PO4-/HPO42- 
E)  HCl/H+

Question 11

Which, if any, of the following acids is strong?

Accepted Answer

A)  phosphoric 
B)  carbonic 
C)  acetic 
D)  water 
E)  None of these choices are correct. 
A)  phosphoric 
B)  carbonic 
C)  acetic 
D)  water 
E)  None of these choices are correct.

Question 12

The strongest base which can exist in water is the hydroxide ion.

Accepted Answer

A) True 
 B)False

Question 13

Select the correct relationship among the concentrations of species present in a 1.0 M aqueous solution of the weak acid represented by HA.

Accepted Answer

A)  [H2O] > [A-] ~ [H3O+] > [HA] > [OH-] 
B)  [H2O] > [HA] > [A-] > [H3O+] > [OH-] 
C)  [HA] > [H2O] > [A-] > [H3O+] > [OH-] 
D)  [H2O] > [HA] > [A-] ~ [H3O+] > [OH-] 
E)  [HA] > [H2O] > [A-] ~ [H3O+] > [OH-] 
A)  [H2O] > [A-] ~ [H3O+] > [HA] > [OH-] 
B)  [H2O] > [HA] > [A-] > [H3O+] > [OH-] 
C)  [HA] > [H2O] > [A-] > [H3O+] > [OH-] 
D)  [H2O] > [HA] > [A-] ~ [H3O+] > [OH-] 
E)  [HA] > [H2O] > [A-] ~ [H3O+] > [OH-]

Question 14

Calcium oxide, CaO, also known as quick lime, will react with carbon dioxide to form calcium carbonate, CaCO3. Which species, if any, acts as a Lewis acid in the reaction?

Accepted Answer

A)  Ca2+ 
B)  O2- 
C)  CO2 
D)  CaCO3 
E)  None of these choices are correct. 
A)  Ca2+ 
B)  O2- 
C)  CO2 
D)  CaCO3 
E)  None of these choices are correct.

Question 15

The substance Ba(OH)2 is considered

Accepted Answer

A)  a weak Arrhenius acid. 
B)  a weak Arrhenius base. 
C)  a strong Arrhenius acid. 
D)  a strong Arrhenius base. 
E)  a neutral compound. 
A)  a weak Arrhenius acid. 
B)  a weak Arrhenius base. 
C)  a strong Arrhenius acid. 
D)  a strong Arrhenius base. 
E)  a neutral compound.

Question 16

It is not possible to have a pH lying outside the range 0 to 14.

Accepted Answer

A) True 
 B)False

Question 17

All strong acids have weak conjugate bases.

Accepted Answer

A) True 
 B)False

Question 18

The ammonium ion, NH4+, is a weak acid.

Accepted Answer

A) True 
 B)False

Question 19

Which one of the following will give a solution with a pH > 7, but is not an Arrhenius base in the strict sense?

Accepted Answer

A)  CH3NH2 
B)  NaOH 
C)  CO2 
D)  Ca(OH)2 
E)  CH4 
A)  CH3NH2 
B)  NaOH 
C)  CO2 
D)  Ca(OH)2 
E)  CH4

Question 20

An aqueous solution is prepared by dissolving the salt formed by the neutralization of a weak acid by a weak base. Which statement about the solution is correct?

Accepted Answer

A)  The solution is strongly basic. 
B)  The solution is weakly basic. 
C)  The solution is neutral. 
D)  The solution is acidic. 
E)  The values for Ka and Kb for the species in solution must be known before a prediction can be made. 
A)  The solution is strongly basic. 
B)  The solution is weakly basic. 
C)  The solution is neutral. 
D)  The solution is acidic. 
E)  The values for Ka and Kb for the species in solution must be known before a prediction can be made.

Exam 18: Acid-Base Equilibria

Which of the following is the strongest acid?

Lactic acid has a pKa of 3.08. What is the approximate degree of dissociation of a 0.35 M solution of lactic acid?

Kw = 1.0 × 10-14, regardless of temperature.

Hydrated metal ions in aqueous solution can act as Brønsted-Lowry acids.

A 1.25 M solution of the weak acid HA is 9.2% dissociated. What is the pH of the solution?

Which of the following pairs has the stronger acid listed first?

Aqueous solutions of phosphoric acid and sodium nitrite are combined, and the following equilibrium is established. H3PO4(aq) + NO2(aq) H2PO4(aq) + HNO2(aq) The equilibrium constant Kc for this reaction is greater than one. Based on this information, which of the following statements is correct?

What is the pH of a 0.20 M HCl solution?

What is the pH of a 0.75 M HNO3 solution?

Which one of the following pairs is not a conjugate acid-base pair?

Which, if any, of the following acids is strong?

The strongest base which can exist in water is the hydroxide ion.

Select the correct relationship among the concentrations of species present in a 1.0 M aqueous solution of the weak acid represented by HA.

Calcium oxide, CaO, also known as quick lime, will react with carbon dioxide to form calcium carbonate, CaCO3. Which species, if any, acts as a Lewis acid in the reaction?

The substance Ba(OH)2 is considered

It is not possible to have a pH lying outside the range 0 to 14.

All strong acids have weak conjugate bases.

The ammonium ion, NH4+, is a weak acid.

Which one of the following will give a solution with a pH > 7, but is not an Arrhenius base in the strict sense?

An aqueous solution is prepared by dissolving the salt formed by the neutralization of a weak acid by a weak base. Which statement about the solution is correct?

Keys to Studying Chemistry Definitions, Units, and Problem Solving

The Components of Matter

Stoichiometry of Formulas and Equations

Three Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces Liquids, Solids, and Phase Changes

The Properties of Mixtures Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Kinetics Rates and Mechanisms of Chemical Reactions

Equilibrium the Extent of Chemical Reactions

Ionic Equilibria in Aqueous Systems

Thermodynamics Entropy, Free Energy, and Reaction Direction

Electrochemistry Chemical Change and Electrical Work

The Elements in Nature and Industry

Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

Lactic acid has a pK_a of 3.08. What is the approximate degree of dissociation of a 0.35 M solution of lactic acid?

K_w = 1.0 × 10^-14, regardless of temperature.

What is the pH of a 0.75 M HNO₃ solution?

Calcium oxide, CaO, also known as quick lime, will react with carbon dioxide to form calcium carbonate, CaCO₃. Which species, if any, acts as a Lewis acid in the reaction?

The substance Ba(OH)₂ is considered

The ammonium ion, NH₄⁺, is a weak acid.