Question 1

Formic acid, which is a component of insect venom, has a Ka = 1.8 × 10−4. What is the [H3O+] in a solution that is initially 0.10 M formic acid, HCOOH?

Accepted Answer

A) 4.2 × 10 −3 M 
B) 8.4 × 10 −3 M 
C) 1.8 × 10 −4 M 
D) 1.8 × 10 −5 M 
E) 1.8 × 10 −6 M 
A) 4.2 × 10 −3 M 
B) 8.4 × 10 −3 M 
C) 1.8 × 10 −4 M 
D) 1.8 × 10 −5 M 
E) 1.8 × 10 −6 M

Question 2

A solution is prepared by adding 0.10 mol of potassium chloride, KCl, 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) One needs to know the temperature before any of these predictions can be made. 
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 basic. 
B) The solution is neutral. 
C) The solution is acidic. 
D) One needs to know the temperature before any of these predictions can be made. 
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

Select the pair of substances that is not a conjugate acid-base pair.

Accepted Answer

A) H 3O +, H 2O 
B) HNO 2, NO 2 − 
C) H 2SO 4, HSO 4 − 
D) H 2S, S 2− 
E) NH 3, NH 2 − 
A) H 3O +, H 2O 
B) HNO 2, NO 2 − 
C) H 2SO 4, HSO 4 − 
D) H 2S, S 2− 
E) NH 3, NH 2 −

Question 4

A 0.15 M solution of chloroacetic acid has a pH of 1.86. What is the value of Ka for this acid?

Accepted Answer

A) 7.2 × 10 1 
B) 0.16 
C) 0.099 
D) 0.0014 
E) 0.00027 
A) 7.2 × 10 1 
B) 0.16 
C) 0.099 
D) 0.0014 
E) 0.00027

Question 5

All strong acids have weak conjugate bases.

Accepted Answer

A) True 
 B)False

Question 6

Select the strongest acid from the following list.

Accepted Answer

A) HBrO 
B) HBrO 2 
C) HClO 2 
D) HClO 3 
E) HIO 
A) HBrO 
B) HBrO 2 
C) HClO 2 
D) HClO 3 
E) HIO

Question 7

The substance H2SO3 is considered

Accepted Answer

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

Question 8

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

Accepted Answer

A) H 2AsO 3, H 2AsO 4 
B) HI, HBr 
C) HClO, HClO 3 
D) H 2S, HCl 
E) H 2SO 3, H 2SO 4 
A) H 2AsO 3, H 2AsO 4 
B) HI, HBr 
C) HClO, HClO 3 
D) H 2S, HCl 
E) H 2SO 3, H 2SO 4

Question 9

Select the pair of substances in that an acid is listed followed by its conjugate base.

Accepted Answer

A) H +, HCl 
B) NH 3, NH 4 + 
C) HPO 4 2−, H 2PO 4 − 
D) HCO 3 −, CO 3 2− 
E) CH 3COOH, CH 3COOH 2 + 
A) H +, HCl 
B) NH 3, NH 4 + 
C) HPO 4 2−, H 2PO 4 − 
D) HCO 3 −, CO 3 2− 
E) CH 3COOH, CH 3COOH 2 +

Question 10

Which of the following is the strongest base?

Accepted Answer

A) CH 3NH 2 
B) NaNO 3 
C) B(OH)3 
D) Al(OH)3 
E) LiOH 
A) CH 3NH 2 
B) NaNO 3 
C) B(OH)3 
D) Al(OH)3 
E) LiOH

Question 11

Which of the following liquids contains the strongest acid?

Accepted Answer

A) 0.1 M HA, pH = 6.85 
B) 0.1 M HD , pH = 7.22 
C) 0.1 M HE, pH = 8.34 
D) 0.1 M HJ , pH = 11.88 
E) Pure water 
A) 0.1 M HA, pH = 6.85 
B) 0.1 M HD , pH = 7.22 
C) 0.1 M HE, pH = 8.34 
D) 0.1 M HJ , pH = 11.88 
E) Pure water

Question 12

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) [H 2O] > [A −] ~ [H 3O +] > [HA] > [OH −] 
B) [H 2O] > [HA] > [A −] > [H 3O +] > [OH −] 
C) [HA] > [H 2O] > [A −] > [H 3O +] > [OH −] 
D) [H 2O] > [HA] > [A −] ~ [H 3O +] > [OH −] 
E) [HA] > [H 2O] > [A −] ~ [H 3O +] > [OH −] 
A) [H 2O] > [A −] ~ [H 3O +] > [HA] > [OH −] 
B) [H 2O] > [HA] > [A −] > [H 3O +] > [OH −] 
C) [HA] > [H 2O] > [A −] > [H 3O +] > [OH −] 
D) [H 2O] > [HA] > [A −] ~ [H 3O +] > [OH −] 
E) [HA] > [H 2O] > [A −] ~ [H 3O +] > [OH −]

Question 13

The substance HClO4 is considered

Accepted Answer

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

Question 14

Farmers who raise cotton once used arsenic acid, H3AsO4, as a defoliant at harvest time. Arsenic acid is a polyprotic acid with K1 = 2.5 × 10−4, K2 = 5.6 × 10−8, and K3 = 3 × 10−13. What is the pH of a 0.500 M solution of arsenic acid?

Accepted Answer

A) 0.85 
B) 1.96 
C) 3.90 
D) 4.51 
E) None of these choices are correct. 
A) 0.85 
B) 1.96 
C) 3.90 
D) 4.51 
E) None of these choices are correct.

Question 15

The substance HCl 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

What is the pH of a 0.010 M triethanolammonium chloride, (HOC2H2)3NHCl, solution?Kb, ((HOC2H2)3N) = 5.9 × 10−7

Accepted Answer

A) 2.75 
B) 4.89 
C) 9.11 
D) 11.25 
E) None of these choices are correct. 
A) 2.75 
B) 4.89 
C) 9.11 
D) 11.25 
E) None of these choices are correct.

Question 17

What is the pH of a 0.00200 M HClO4 solution?

Accepted Answer

A) 0.995 
B) 1.378 
C) 2.699 
D) 6.215 
E) None of these choices are correct. 
A) 0.995 
B) 1.378 
C) 2.699 
D) 6.215 
E) None of these choices are correct.

Question 18

According to Brønsted and Lowry, which one of the following is not a conjugate acid-base pair?

Accepted Answer

A) H 3O +/OH − 
B) CH 3OH 2 +/CH 3OH 
C) HI/I − 
D) HSO 4 −/SO 4 2− 
E) H 2/H − 
A) H 3O +/OH − 
B) CH 3OH 2 +/CH 3OH 
C) HI/I − 
D) HSO 4 −/SO 4 2− 
E) H 2/H −

Question 19

Which of the following acids has the lowest pH?0.1 M HBO, pKa = 2.430.1 M HA, pKa = 4.550.1 M HMO, pKa = 8.230.1 M HST, pKa = 11.89pure water

Accepted Answer

A) HA 
B) HST 
C) HMO 
D) HBO 
E) Pure water 
A) HA 
B) HST 
C) HMO 
D) HBO 
E) Pure water

Question 20

The hydrated Al3+ ion, Al(H2O)63+, is a weak acid in water. What are the products of its reaction with H2O?Al(H2O)63+(aq) + H2O(l) → ?

Accepted Answer

A) Al(H 2O)5OH 2+( aq)+ H 3O +( aq) 
B) Al(H 2O)6H 4+( aq)+ OH −( aq) 
C) Al(H 2O)5 3+( aq)+ 2H 2O( l) 
D) Al(H 2O)6OH 2+( aq)+ H 3O +( aq) 
E) Al(H 2O)6 2+( aq)+ H 3O +( aq) 
A) Al(H 2O)5OH 2+( aq)+ H 3O +( aq) 
B) Al(H 2O)6H 4+( aq)+ OH −( aq) 
C) Al(H 2O)5 3+( aq)+ 2H 2O( l) 
D) Al(H 2O)6OH 2+( aq)+ H 3O +( aq) 
E) Al(H 2O)6 2+( aq)+ H 3O +( aq)

Exam 18: Acid-Base Equilibria

Formic acid, which is a component of insect venom, has a Ka = 1.8 × 10−4. What is the [H3O+] in a solution that is initially 0.10 M formic acid, HCOOH?

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

Select the pair of substances that is not a conjugate acid-base pair.

A 0.15 M solution of chloroacetic acid has a pH of 1.86. What is the value of Ka for this acid?

All strong acids have weak conjugate bases.

Select the strongest acid from the following list.

The substance H2SO3 is considered

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

Select the pair of substances in that an acid is listed followed by its conjugate base.

Which of the following is the strongest base?

Which of the following liquids contains the strongest acid?

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

The substance HClO4 is considered

Farmers who raise cotton once used arsenic acid, H3AsO4, as a defoliant at harvest time. Arsenic acid is a polyprotic acid with K1 = 2.5 × 10−4, K2 = 5.6 × 10−8, and K3 = 3 × 10−13. What is the pH of a 0.500 M solution of arsenic acid?

The substance HCl is considered

What is the pH of a 0.010 M triethanolammonium chloride, (HOC2H2)3NHCl, solution?Kb, ((HOC2H2)3N) = 5.9 × 10−7

What is the pH of a 0.00200 M HClO4 solution?

According to Brønsted and Lowry, which one of the following is not a conjugate acid-base pair?

Which of the following acids has the lowest pH?0.1 M HBO, pKa = 2.430.1 M HA, pKa = 4.550.1 M HMO, pKa = 8.230.1 M HST, pKa = 11.89pure water

The hydrated Al3+ ion, Al(H2O)63+, is a weak acid in water. What are the products of its reaction with H2O?Al(H2O)63+(aq) + H2O(l) → ?

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

Formic acid, which is a component of insect venom, has a K_a = 1.8 × 10⁻⁴. What is the [H₃O⁺] in a solution that is initially 0.10 M formic acid, HCOOH?

A 0.15 M solution of chloroacetic acid has a pH of 1.86. What is the value of K_a for this acid?

The substance H₂SO₃is considered

The substance HClO₄is considered

Farmers who raise cotton once used arsenic acid, H₃AsO₄, as a defoliant at harvest time. Arsenic acid is a polyprotic acid with K₁ = 2.5 × 10⁻⁴, K₂ = 5.6 × 10⁻⁸, and K₃ = 3 × 10⁻¹³. What is the pH of a 0.500 M solution of arsenic acid?

What is the pH of a 0.010 M triethanolammonium chloride, (HOC₂H₂)₃NHCl, solution?K_b, ((HOC₂H₂)₃N) = 5.9 × 10⁻⁷

What is the pH of a 0.00200 M HClO₄solution?

Which of the following acids has the lowest pH?0.1 M HBO, pK_a = 2.430.1 M HA, pK_a = 4.550.1 M HMO, pK_a = 8.230.1 M HST, pK_a = 11.89pure water

The hydrated Al³⁺ ion, Al(H₂O)₆³⁺, is a weak acid in water. What are the products of its reaction with H₂O?Al(H₂O)₆³⁺(aq) + H₂O(l) → ?