Question 1

What will be the effect of adding 0.5 mL of 0.1 M HCl to 100 mL of a phosphate buffer in which [H2PO4-] = [HPO42-] = 0.35 M?

Accepted Answer

A)  The pH will increase slightly. 
B)  The pH will increase significantly. 
C)  The pH will decrease slightly. 
D)  The pH will decrease significantly. 
E)  Since it is a buffer solution, the pH will not be affected. 
A)  The pH will increase slightly. 
B)  The pH will increase significantly. 
C)  The pH will decrease slightly. 
D)  The pH will decrease significantly. 
E)  Since it is a buffer solution, the pH will not be affected.

Question 2

A formic acid buffer containing 0.50 M HCOOH and 0.50 M HCOONa has a pH of 3.77. What will the pH be after 0.010 mol of NaOH has been added to 100.0 mL of the buffer?

Accepted Answer

A)  3.67 
B)  3.78 
C)  3.81 
D)  3.85 
E)  3.95 
A)  3.67 
B)  3.78 
C)  3.81 
D)  3.85 
E)  3.95

Question 3

A solution is prepared by adding 500 mL of 0.3 M NaClO to 500 mL of 0.4 M HClO. What is the pH of this solution?

Accepted Answer

A)  The pH will be greater than the pKa of hypochlorous acid. 
B)  The pH will be less than the pKa of hypochlorous acid. 
C)  The pH will be equal to the pKa of hypochlorous acid. 
D)  The pH will equal the pKb of sodium hypochlorite. 
E)  None of these choices are correct. 
A)  The pH will be greater than the pKa of hypochlorous acid. 
B)  The pH will be less than the pKa of hypochlorous acid. 
C)  The pH will be equal to the pKa of hypochlorous acid. 
D)  The pH will equal the pKb of sodium hypochlorite. 
E)  None of these choices are correct.

Question 4

A 10.0-mL sample of 0.75 M CH3CH2COOH is titrated with 0.30 M NaOH. What is the pH of the solution after 22.0 mL of NaOH have been added to the acid? Ka = 1.3 × 10-5

Accepted Answer

A)  5.75 
B)  4.94 
C)  4.83 
D)  4.02 
E)  3.95 
A)  5.75 
B)  4.94 
C)  4.83 
D)  4.02 
E)  3.95

Question 5

Increasing the concentrations of the components of a buffer solution will increase the buffer range.

Accepted Answer

A) True 
 B)False

Question 6

A CH3COOH/CH3COO- buffer can be produced by adding a strong acid to a solution of CH3COO- ions.

Accepted Answer

A) True 
 B)False

Question 7

A 50.0-mL sample of 0.50 M HCl is titrated with 0.50 M NaOH. What is the pH of the solution after 28.0 mL of NaOH have been added to the acid?

Accepted Answer

A)  0.85 
B)  0.75 
C)  0.66 
D)  0.49 
E)  3.8 
A)  0.85 
B)  0.75 
C)  0.66 
D)  0.49 
E)  3.8

Question 8

What is the maximum mass of KCl that can be added to1.0 L of a 0.010 M lead(II) chloride solution without causing any precipitation of lead(II) chloride? Assume that addition of KCl does not affect the solution volume. For lead(II) chloride, Ksp = 1.6 × 10-5.

Accepted Answer

A)  3.0 g 
B)  1.5 g 
C)  0.8 g 
D)  1.0 g 
E)  0.2 g 
A)  3.0 g 
B)  1.5 g 
C)  0.8 g 
D)  1.0 g 
E)  0.2 g

Question 9

A 20.0-mL sample of 0.25 M HNO3 is titrated with 0.15 M NaOH. What is the pH of the solution after 30.0 mL of NaOH have been added to the acid?

Accepted Answer

A)  2.00 
B)  1.60 
C)  1.05 
D)  1.00 
E)  None of these choices are correct. 
A)  2.00 
B)  1.60 
C)  1.05 
D)  1.00 
E)  None of these choices are correct.

Question 10

Two buffer solutions are prepared using acetic acid and sodium acetate. Solution A contains 20.0 g of acetic acid (CH3COOH) and 5.0 g of sodium acetate CH3COONa). Solution B contains 10.0 g of acetic acid and 25.0 g of sodium acetate. What is the difference between the pH values of these two solutions? For acetic acid, Ka = 1.8 × 10-5.

Accepted Answer

A)  0.0 
B)  1.0 
C)  2.0 
D)  2.3 
E)  4.6 
A)  0.0 
B)  1.0 
C)  2.0 
D)  2.3 
E)  4.6

Question 11

What is the [H3O+] in a solution that consists of 0.15 M C2N2H8 (ethylene diamine) and 0.35 C2N2H9Cl? Kb = 4.7 × 10-4

Accepted Answer

A)  2.0 × 10-3 M 
B)  1.1 × 10-3 M 
C)  6.3 × 10-9 M 
D)  2.1 × 10-10 M 
E)  5.0 × 10-11 M 
A)  2.0 × 10-3 M 
B)  1.1 × 10-3 M 
C)  6.3 × 10-9 M 
D)  2.1 × 10-10 M 
E)  5.0 × 10-11 M

Question 12

An acetic acid buffer containing 0.50 M CH3COOH and 0.50 M CH3COONa has a pH of 4.74. What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer?

Accepted Answer

A)  4.77 
B)  4.71 
C)  4.68 
D)  4.62 
E)  None of these choices are correct. 
A)  4.77 
B)  4.71 
C)  4.68 
D)  4.62 
E)  None of these choices are correct.

Question 13

A 25.0-mL sample of 1.00 M NH3 is titrated with 0.15 M HCl. What is the pH of the solution after 15.00 mL of acid have been added to the ammonia solution? Kb = 1.8 × 10-5

Accepted Answer

A)  10.26 
B)  9.30 
C)  9.21 
D)  8.30 
E)  8.21 
A)  10.26 
B)  9.30 
C)  9.21 
D)  8.30 
E)  8.21

Question 14

The salts X(NO3)2 and Y(NO3)2 (where X+ and Y+ are metal ions) are dissolved in water to give a solution which is 0.1 M in each of them. Using the Ksp values listed below, decide which aqueous reagent, if any, will definitely precipitate X+ before precipitating Y+ from solution. Given Ksp values:
XCl2, 1 × 10-5 YCl2, 1 × 10-10 X(OH)2, 1 × 10-10 Y(OH)2, 1 × 10-5

Accepted Answer

A)  1 M NH3 
B)  1 M HCl 
C)  1 M HNO3 
D)  1 M NaCl 
E)  None of these choices are correct. 
A)  1 M NH3 
B)  1 M HCl 
C)  1 M HNO3 
D)  1 M NaCl 
E)  None of these choices are correct.

What will be the effect of adding 0.5 mL of 0.1 M HCl to 100 mL of a phosphate buffer in which [H₂PO₄^-] = [HPO₄^2-] = 0.35 M?

A formic acid buffer containing 0.50 M HCOOH and 0.50 M HCOONa has a pH of 3.77. What will the pH be after 0.010 mol of NaOH has been added to 100.0 mL of the buffer?

A solution is prepared by adding 500 mL of 0.3 M NaClO to 500 mL of 0.4 M HClO. What is the pH of this solution?

A 10.0-mL sample of 0.75 M CH₃CH₂COOH is titrated with 0.30 M NaOH. What is the pH of the solution after 22.0 mL of NaOH have been added to the acid? K_a = 1.3 × 10^-5

Increasing the concentrations of the components of a buffer solution will increase the buffer range.

A CH₃COOH/CH₃COO- buffer can be produced by adding a strong acid to a solution of CH₃COO- ions.

A 50.0-mL sample of 0.50 M HCl is titrated with 0.50 M NaOH. What is the pH of the solution after 28.0 mL of NaOH have been added to the acid?

What is the maximum mass of KCl that can be added to1.0 L of a 0.010 M lead(II) chloride solution without causing any precipitation of lead(II) chloride? Assume that addition of KCl does not affect the solution volume. For lead(II) chloride, K_sp = 1.6 × 10^-5.

A 20.0-mL sample of 0.25 M HNO₃ is titrated with 0.15 M NaOH. What is the pH of the solution after 30.0 mL of NaOH have been added to the acid?

What is the [H₃O⁺] in a solution that consists of 0.15 M C₂N₂H₈ (ethylene diamine) and 0.35 C₂N₂H₉Cl? K_b = 4.7 × 10^-4

An acetic acid buffer containing 0.50 M CH₃COOH and 0.50 M CH₃COONa has a pH of 4.74. What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer?

A 25.0-mL sample of 1.00 M NH₃ is titrated with 0.15 M HCl. What is the pH of the solution after 15.00 mL of acid have been added to the ammonia solution? K_b = 1.8 × 10^-5

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

Acid-Base Equilibria

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

Exam 19: Ionic Equilibria in Aqueous Systems

What will be the effect of adding 0.5 mL of 0.1 M HCl to 100 mL of a phosphate buffer in which [H2PO4-] = [HPO42-] = 0.35 M?

A formic acid buffer containing 0.50 M HCOOH and 0.50 M HCOONa has a pH of 3.77. What will the pH be after 0.010 mol of NaOH has been added to 100.0 mL of the buffer?

A solution is prepared by adding 500 mL of 0.3 M NaClO to 500 mL of 0.4 M HClO. What is the pH of this solution?

A 10.0-mL sample of 0.75 M CH3CH2COOH is titrated with 0.30 M NaOH. What is the pH of the solution after 22.0 mL of NaOH have been added to the acid? Ka = 1.3 × 10-5

Increasing the concentrations of the components of a buffer solution will increase the buffer range.

A CH3COOH/CH3COO- buffer can be produced by adding a strong acid to a solution of CH3COO- ions.

A 50.0-mL sample of 0.50 M HCl is titrated with 0.50 M NaOH. What is the pH of the solution after 28.0 mL of NaOH have been added to the acid?

What is the maximum mass of KCl that can be added to1.0 L of a 0.010 M lead(II) chloride solution without causing any precipitation of lead(II) chloride? Assume that addition of KCl does not affect the solution volume. For lead(II) chloride, Ksp = 1.6 × 10-5.

A 20.0-mL sample of 0.25 M HNO3 is titrated with 0.15 M NaOH. What is the pH of the solution after 30.0 mL of NaOH have been added to the acid?

What is the [H3O+] in a solution that consists of 0.15 M C2N2H8 (ethylene diamine) and 0.35 C2N2H9Cl? Kb = 4.7 × 10-4

An acetic acid buffer containing 0.50 M CH3COOH and 0.50 M CH3COONa has a pH of 4.74. What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer?

A 25.0-mL sample of 1.00 M NH3 is titrated with 0.15 M HCl. What is the pH of the solution after 15.00 mL of acid have been added to the ammonia solution? Kb = 1.8 × 10-5

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

Acid-Base Equilibria

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 will be the effect of adding 0.5 mL of 0.1 M HCl to 100 mL of a phosphate buffer in which [H₂PO₄^-] = [HPO₄^2-] = 0.35 M?

A 10.0-mL sample of 0.75 M CH₃CH₂COOH is titrated with 0.30 M NaOH. What is the pH of the solution after 22.0 mL of NaOH have been added to the acid? K_a = 1.3 × 10^-5

A CH₃COOH/CH₃COO- buffer can be produced by adding a strong acid to a solution of CH₃COO- ions.

What is the maximum mass of KCl that can be added to1.0 L of a 0.010 M lead(II) chloride solution without causing any precipitation of lead(II) chloride? Assume that addition of KCl does not affect the solution volume. For lead(II) chloride, K_sp = 1.6 × 10^-5.

A 20.0-mL sample of 0.25 M HNO₃ is titrated with 0.15 M NaOH. What is the pH of the solution after 30.0 mL of NaOH have been added to the acid?

What is the [H₃O⁺] in a solution that consists of 0.15 M C₂N₂H₈ (ethylene diamine) and 0.35 C₂N₂H₉Cl? K_b = 4.7 × 10^-4

An acetic acid buffer containing 0.50 M CH₃COOH and 0.50 M CH₃COONa has a pH of 4.74. What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer?

A 25.0-mL sample of 1.00 M NH₃ is titrated with 0.15 M HCl. What is the pH of the solution after 15.00 mL of acid have been added to the ammonia solution? K_b = 1.8 × 10^-5