Question 1

What is the [OH−] for a solution at 25°C that has pH = 4.29?

Accepted Answer

A) 1.4 × 10 −2  M 
B) 5.l × 10 −5  M 
C) 1.9 × 10 −10  M 
D) 7.3 × 10 −13  M 
E) 9.71 M 
A) 1.4 × 10 −2  M 
B) 5.l × 10 −5  M 
C) 1.9 × 10 −10  M 
D) 7.3 × 10 −13  M 
E) 9.71 M

Question 2

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 K a and K b 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 K a and K b for the species in solution must be known before a prediction can be made.

Question 3

Which one of the following is a strong acid?

Accepted Answer

A) H 2CO 3 
B) H 2SO 3 
C) H 2SO 4 
D) H 3PO 4 
E) CH 3COOH 
A) H 2CO 3 
B) H 2SO 3 
C) H 2SO 4 
D) H 3PO 4 
E) CH 3COOH

Question 4

What is the [OH−] for a solution at 25°C that has [H3O+] = 2.35 × 10−3 M?

Accepted Answer

A) 4.26 × 10 −5  M 
B) 2.35 × 10 −11 M 
C) 4.26 × 10 −12 M 
D) 2.35 × 10 −17  M 
E) None of these choices are correct. 
A) 4.26 × 10 −5  M 
B) 2.35 × 10 −11 M 
C) 4.26 × 10 −12 M 
D) 2.35 × 10 −17  M 
E) None of these choices are correct.

Question 5

Which of the following is a Lewis base?

Accepted Answer

A) BCl 3 
B) Cu 2+ 
C) Cl − 
D) Mn 2+ 
E) NH 4 + 
A) BCl 3 
B) Cu 2+ 
C) Cl − 
D) Mn 2+ 
E) NH 4 +

Question 6

Which of the following is considered a Lewis acid?

Accepted Answer

A) CH 3NH 2 
B) BCl 3 
C) F − 
D) BF 4 − 
E) CH 4 
A) CH 3NH 2 
B) BCl 3 
C) F − 
D) BF 4 − 
E) CH 4

Question 7

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 8

What is the [OH−] for a solution at 25°C that has [H3O+] = 8.23 × 10−2 M?

Accepted Answer

A) > 10 −5 M 
B) 1.22 × 10 −6  M 
C) 8.23 × 10 −12  M 
D) 1.22 × 10 −13  M 
E) 8.23 × 10 −16  M 
A) > 10 −5 M 
B) 1.22 × 10 −6  M 
C) 8.23 × 10 −12  M 
D) 1.22 × 10 −13  M 
E) 8.23 × 10 −16  M

Question 9

A student adds 0.1 mol of oxalic acid and 0.1 mol of sodium dihydrogen phosphate to enough water to make 1.0 L of solution. The following equilibrium is established with the concentrations of the products greater than the concentrations of the reactants. Which of the statements about the equilibrium system is correct? H2C2O4(aq) + H2PO4(aq)⇄ HC2O4(aq) + H3PO4(aq)

Accepted Answer

A) Oxalic acid is a weaker acid than phosphoric acid. 
B) The hydrogen oxalate anion, HC 2O 4, is a stronger base than the dihydrogen phosphate anion, H 2PO 4. 
C) Phosphoric acid is a weaker acid than oxalic acid. 
D) The dihydrogen phosphate anion, H 2PO 4 −, is a stronger acid than oxalic acid. 
E) Water is a stronger acid than either oxalic or phosphoric acids. 
A) Oxalic acid is a weaker acid than phosphoric acid. 
B) The hydrogen oxalate anion, HC 2O 4, is a stronger base than the dihydrogen phosphate anion, H 2PO 4. 
C) Phosphoric acid is a weaker acid than oxalic acid. 
D) The dihydrogen phosphate anion, H 2PO 4 −, is a stronger acid than oxalic acid. 
E) Water is a stronger acid than either oxalic or phosphoric acids.

Question 10

An aqueous solution is considered to be acidic if

Accepted Answer

A) the hydroxide ion concentration is 10 −6 M. 
B) the hydrogen ion concentration is 10 −8 M. 
C) the hydroxide and hydrogen ion concentrations are equal. 
D) the hydroxide ion concentration is greater than the hydrogen ion concentration. 
E) the hydroxide ion concentration is 10 −10 M. 
A) the hydroxide ion concentration is 10 −6 M. 
B) the hydrogen ion concentration is 10 −8 M. 
C) the hydroxide and hydrogen ion concentrations are equal. 
D) the hydroxide ion concentration is greater than the hydrogen ion concentration. 
E) the hydroxide ion concentration is 10 −10 M.

Question 11

What is the pH of a 0.0125 M NaOH solution?

Accepted Answer

A) 0.972 
B) 1.903 
C) 12.097 
D) 13.028 
E) None of these choices are correct. 
A) 0.972 
B) 1.903 
C) 12.097 
D) 13.028 
E) None of these choices are correct.

Question 12

In applying molecular orbital theory, the bond order is calculated in the same way as with Lewis structures.

Accepted Answer

A) True 
 B)False

Question 13

Iodine trichloride, ICl3, will react with a chloride ion to form ICl4−. Which species, if any, acts as a Lewis acid this reaction?

Accepted Answer

A) ICl 4 − 
B) ICl 3 
C) Cl − 
D) The solvent 
E) None of these choices are correct. 
A) ICl 4 − 
B) ICl 3 
C) Cl − 
D) The solvent 
E) None of these choices are correct.

Question 14

What is the pH of a 0.050 M triethylamine, (C2H5)3N, solution?Kb for triethylamine is 5.3 × 10−4.

Accepted Answer

A) 11.69 
B) 8.68 
C) 5.32 
D) 2.31 
E) < 2.0 
A) 11.69 
B) 8.68 
C) 5.32 
D) 2.31 
E) < 2.0

Question 15

Butyric acid is responsible for the odor in rancid butter. A solution of 0.25 M butyric acid has a pH of 2.71. What is the Ka for the acid?

Accepted Answer

A) 0.36 
B) 2.4 × 10 −2 
C) 7.8 × 10 −3 
D) 1.5 × 10 −5 
E) None of these choices are correct. 
A) 0.36 
B) 2.4 × 10 −2 
C) 7.8 × 10 −3 
D) 1.5 × 10 −5 
E) None of these choices are correct.

Question 16

What is the pH of a 0.0035 M KOH solution?

Accepted Answer

A) 2.46 
B) 5.65 
C) 8.35 
D) 11.54 
E) None of these choices are correct. 
A) 2.46 
B) 5.65 
C) 8.35 
D) 11.54 
E) None of these choices are correct.

Question 17

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 18

A solution is prepared by adding 0.10 mol of potassium acetate, KCH3COO, to 1.00 L of water. Which statement about the solution is correct?

Accepted Answer

A) The solution is basic. 
B) The solution is neutral. 
C) The solution is acidic. 
D) The concentrations of potassium ions and acetate ions will be identical. 
E) The concentration of acetate ions will be greater than the concentration of potassium ions. 
A) The solution is basic. 
B) The solution is neutral. 
C) The solution is acidic. 
D) The concentrations of potassium ions and acetate ions will be identical. 
E) The concentration of acetate ions will be greater than the concentration of potassium ions.

Question 19

In order to be a Brønsted-Lowry base, a species must contain a proton.

Accepted Answer

A) True 
 B)False

Question 20

What is the pOH of a 0.0250 M HI solution?

Accepted Answer

A) 0.944 
B) 1.602 
C) 12.398 
D) 13.056 
E) None of these choices are correct. 
A) 0.944 
B) 1.602 
C) 12.398 
D) 13.056 
E) None of these choices are correct.

Exam 18: Acid-Base Equilibria

What is the [OH−] for a solution at 25°C that has pH = 4.29?

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?

Which one of the following is a strong acid?

What is the [OH−] for a solution at 25°C that has [H3O+] = 2.35 × 10−3 M?

Which of the following is a Lewis base?

Which of the following is considered a Lewis acid?

What is the pH of a 0.75 M HNO3 solution?

What is the [OH−] for a solution at 25°C that has [H3O+] = 8.23 × 10−2 M?

An aqueous solution is considered to be acidic if

What is the pH of a 0.0125 M NaOH solution?

In applying molecular orbital theory, the bond order is calculated in the same way as with Lewis structures.

Iodine trichloride, ICl3, will react with a chloride ion to form ICl4−. Which species, if any, acts as a Lewis acid this reaction?

What is the pH of a 0.050 M triethylamine, (C2H5)3N, solution?Kb for triethylamine is 5.3 × 10−4.

Butyric acid is responsible for the odor in rancid butter. A solution of 0.25 M butyric acid has a pH of 2.71. What is the Ka for the acid?

What is the pH of a 0.0035 M KOH solution?

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?

A solution is prepared by adding 0.10 mol of potassium acetate, KCH3COO, to 1.00 L of water. Which statement about the solution is correct?

In order to be a Brønsted-Lowry base, a species must contain a proton.

What is the pOH of a 0.0250 M HI solution?

Keys to the Study of 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

What is the [OH⁻] for a solution at 25°C that has pH = 4.29?

What is the [OH⁻] for a solution at 25°C that has [H₃O⁺] = 2.35 × 10⁻³ M?

What is the pH of a 0.75 M HNO₃solution?

What is the [OH⁻] for a solution at 25°C that has [H₃O⁺] = 8.23 × 10⁻²M?

Iodine trichloride, ICl₃, will react with a chloride ion to form ICl₄⁻. Which species, if any, acts as a Lewis acid this reaction?

What is the pH of a 0.050 M triethylamine, (C₂H₅)₃N, solution?K_b for triethylamine is 5.3 × 10⁻⁴.

Butyric acid is responsible for the odor in rancid butter. A solution of 0.25 M butyric acid has a pH of 2.71. What is the K_a for the acid?

A solution is prepared by adding 0.10 mol of potassium acetate, KCH₃COO, to 1.00 L of water. Which statement about the solution is correct?