Question 1

What is the conjugate acid of hydrogen carbonate ion, HCO3 -  ?

Accepted Answer

A)  H3O+ 
B)  OH - 
C)  H2O 
D)  CO32 - 
E)  H2CO3 
A)  H3O+ 
B)  OH - 
C)  H2O 
D)  CO32 - 
E)  H2CO3

Question 2

When would the pH of a solution prepared by adding sodium formate to formic acid be equal to the pKa of formic acid, HCO2H?

Accepted Answer

A)  when [HCO2H] 2-] 
B)  when [HCO2H] = [HCO2-] 
C)  when [HCO2H] > [HCO2-] 
D)  The pH of this buffer will never equal the pKa of formic acid. 
E)  When the temperature is 25°C. 
A)  when [HCO2H] 2-] 
B)  when [HCO2H] = [HCO2-] 
C)  when [HCO2H] > [HCO2-] 
D)  The pH of this buffer will never equal the pKa of formic acid. 
E)  When the temperature is 25°C.

Question 3

What is the pH of a solution that is 0.01 M in CH3NH2 and 0.1 M in CH3NH3+?

CH3NH2(aq) + H2O(l)   CH3NH3+(aq) + OH-(aq) Kb = 4.4 x 10-4

Accepted Answer

A)  2.36 
B)  3.36 
C)  9.64 
D)  10.64 
E)  11.64 
A)  2.36 
B)  3.36 
C)  9.64 
D)  10.64 
E)  11.64

Question 4

Which of the following would be the strongest Brønsted base?

Accepted Answer

A)  HSO3- 
B)  HSO4- 
C)  H2SO3 
D)  SO32- 
E)  SO42- 
A)  HSO3- 
B)  HSO4- 
C)  H2SO3 
D)  SO32- 
E)  SO42-

Question 5

Which of the following is the best Lewis structure for carbonic acid (H2CO3)?

Accepted Answer

A)   
B)   
C)    
D)   
E)   
A)   
B)   
C)    
D)   
E)

Question 6

A diprotic acid, H2A, has the following dissociation constants:
Ka1 = 2.1 x 10-7 and Ka2 = 4.3 x 10-13. The H3O+ ion concentration when this acid is dissolved in water is

Accepted Answer

A)  roughly equal to the H2A concentration. 
B)  much larger than the H2A concentration. 
C)  much larger than the HA- concentration. 
D)  approximately equal to the HA- concentration. 
E)  much less than the HA- concentration. 
A)  roughly equal to the H2A concentration. 
B)  much larger than the H2A concentration. 
C)  much larger than the HA- concentration. 
D)  approximately equal to the HA- concentration. 
E)  much less than the HA- concentration.

Question 7

Which of the following acids would have the strongest conjugate base?

Accepted Answer

A)  HOCl (Ka = 2.9 x 10-8) 
B)  HOBr (Ka = 2.4 x 10-9) 
C)  HOI (Ka = 2.3 x 10-11) 
D)  H2O2 (Ka = 2.2 x 10-12) 
E)  H2O (Ka = 1.8 x 10-16) 
A)  HOCl (Ka = 2.9 x 10-8) 
B)  HOBr (Ka = 2.4 x 10-9) 
C)  HOI (Ka = 2.3 x 10-11) 
D)  H2O2 (Ka = 2.2 x 10-12) 
E)  H2O (Ka = 1.8 x 10-16)

Question 8

The salt NaF is dissolved in water. Which of the following relationships would be true for the species in solution?

Accepted Answer

A)  [Na+]    [F - ] >> [HF]    [H3O+] >> [OH - ] 
B)  [Na+]     [F - ] >> [HF]    [OH - ] >> [H3O+] 
C)  [Na+] >> [F - ]     [HF]    [OH - ] >> [H3O+] 
D)  [Na+]     [HF] >> [F - ]    [OH - ] >> [H3O+] 
E)  none of these 
A)  [Na+]    [F - ] >> [HF]    [H3O+] >> [OH - ] 
B)  [Na+]     [F - ] >> [HF]    [OH - ] >> [H3O+] 
C)  [Na+] >> [F - ]     [HF]    [OH - ] >> [H3O+] 
D)  [Na+]     [HF] >> [F - ]    [OH - ] >> [H3O+] 
E)  none of these

Question 9

Explain the following observation: Water becomes acidic when CO2 is bubbled into it.

Accepted Answer

Because of the forma

Question 10

For a weak diprotic acid, H2A, for which Ka1 = 2.1 x 10-7 and
Ka2 = 4.3 x 10-13 the A2- ion concentration at equilibrium will be:

Accepted Answer

A)  approximately equal to the initial concentration of H2A. 
B)  roughly equal to Ka2. 
C)  roughly equal to the HA- concentration. 
D)  much larger than the HA- concentration. 
E)  approximately equal to the H3O+ concentration. 
A)  approximately equal to the initial concentration of H2A. 
B)  roughly equal to Ka2. 
C)  roughly equal to the HA- concentration. 
D)  much larger than the HA- concentration. 
E)  approximately equal to the H3O+ concentration.

Question 11

Which of the following compounds can act as either a Brønsted acid or a Brønsted base?
(I) NaHCO3 (II) Na2CO3 (III) H2CO3 (IV) CO2 (V) H2O

Accepted Answer

A)  I 
B)  I and II 
C)  II and III 
D)  I and V 
E)  V 
A)  I 
B)  I and II 
C)  II and III 
D)  I and V 
E)  V

Question 12

Which of the following would you expect to be the strongest acid?

Accepted Answer

A)  NH3 
B)  PH3 
C)  H2O 
D)  H2S 
E)  CH4 
A)  NH3 
B)  PH3 
C)  H2O 
D)  H2S 
E)  CH4

Question 13

What is the hydroxide ion concentration in a pH = 5.14 solution?

Accepted Answer

A)  1.0 x 10-14 
B)  1.4 x 10-9 
C)  1.0 x 10-7 
D)  7.2 x 10-6 
E)  1.4 x 10-2 
A)  1.0 x 10-14 
B)  1.4 x 10-9 
C)  1.0 x 10-7 
D)  7.2 x 10-6 
E)  1.4 x 10-2

Question 14

What is the pH of a 0.10 M H2CO3 solution?
(H2CO3: Ka1 = 4.2 x 10-7, Ka2 = 4.8 x 10-11)

Accepted Answer

A)  3.1 
B)  3.7 
C)  6.3 
D)  6.8 
E)  none of the above 
A)  3.1 
B)  3.7 
C)  6.3 
D)  6.8 
E)  none of the above

Question 15

Ethanol (CH3CH2OH), like water, can behave both as an acid or as a base. Which of the following structures corresponds to the Brønsted conjugate acid and conjugate base of ethanol?

Accepted Answer

A)     
B)     
C)      
D)      
E)  none of these 
A)     
B)     
C)      
D)      
E)  none of these

Question 16

Calculate the approximate pH of a 0.10 M lactic acid solution.
(Ka = 8.4 x 10-4)

Accepted Answer

A)  2.0 
B)  3.0 
C)  4.0 
D)  7.0 
E)  12.0 
A)  2.0 
B)  3.0 
C)  4.0 
D)  7.0 
E)  12.0

Question 17

Determine the [OH   ] for an aqueous solution at 25   C with a pH of 4.80.

Accepted Answer

A)  6.3x10  10M 
B)  1.6x10  5M 
C)  1.6x10  9M 
D)  8.0x10  8M 
E)  none of these 
A)  6.3x10  10M 
B)  1.6x10  5M 
C)  1.6x10  9M 
D)  8.0x10  8M 
E)  none of these

Question 18

Use the following acid-dissociation equilibrium constants for 
  
-0.5 M solutions of NaA, NaB, NaC, and NaD are prepared. Which solution is the most basic?

Accepted Answer

A)  NaA 
B)  NaB 
C)  NaC 
D)  NaD 
E)  All of the solutions have the same pH. 
A)  NaA 
B)  NaB 
C)  NaC 
D)  NaD 
E)  All of the solutions have the same pH.

Question 19

Which of the following structural factors is primarily responsible for H2AsO4 - being a stronger acid than HAsO42 - ?

Accepted Answer

A)  bond polarity 
B)  size of the anion 
C)  electron withdrawing effect of oxygen 
D)  electric charge on the acid 
E)  arsenic has d electrons 
A)  bond polarity 
B)  size of the anion 
C)  electron withdrawing effect of oxygen 
D)  electric charge on the acid 
E)  arsenic has d electrons

Question 20

Arrange the following bases in order of increasing strength: NH3, PH3, H2O and H2S.

Accepted Answer

What is the conjugate acid of hydrogen carbonate ion, HCO₃ ^- ?

When would the pH of a solution prepared by adding sodium formate to formic acid be equal to the pK_a of formic acid, HCO₂H?

What is the pH of a solution that is 0.01 M in CH₃NH₂ and 0.1 M in CH₃NH₃⁺? CH₃NH₂(aq) + H₂O(l) CH₃NH₃⁺(aq) + OH^-(aq) K_b = 4.4 x 10^-4

Which of the following would be the strongest Brønsted base?

Which of the following is the best Lewis structure for carbonic acid (H₂CO₃)?

A diprotic acid, H₂A, has the following dissociation constants: K_a1 = 2.1 x 10^-7 and K_a2 = 4.3 x 10^-13. The H₃O⁺ ion concentration when this acid is dissolved in water is

Which of the following acids would have the strongest conjugate base?

The salt NaF is dissolved in water. Which of the following relationships would be true for the species in solution?

Explain the following observation: Water becomes acidic when CO₂ is bubbled into it.

For a weak diprotic acid, H₂A, for which K_a1 = 2.1 x 10^-7 and K_a2 = 4.3 x 10^-13 the A^2- ion concentration at equilibrium will be:

Which of the following compounds can act as either a Brønsted acid or a Brønsted base? (I) NaHCO₃ (II) Na₂CO₃ (III) H₂CO₃ (IV) CO₂ (V) H₂O

Which of the following would you expect to be the strongest acid?

What is the hydroxide ion concentration in a pH = 5.14 solution?

What is the pH of a 0.10 M H₂CO₃ solution? (H₂CO₃: K_a1 = 4.2 x 10^-7, K_a2 = 4.8 x 10^-11)

Ethanol (CH₃CH₂OH), like water, can behave both as an acid or as a base. Which of the following structures corresponds to the Brønsted conjugate acid and conjugate base of ethanol?

Calculate the approximate pH of a 0.10 M lactic acid solution. (K_a = 8.4 x 10^-4)

Determine the [OH ] for an aqueous solution at 25 C with a pH of 4.80.

Use the following acid-dissociation equilibrium constants for -0.5 M solutions of NaA, NaB, NaC, and NaD are prepared. Which solution is the most basic?

Which of the following structural factors is primarily responsible for H₂AsO₄ ^- being a stronger acid than HAsO₄² ^- ?

Arrange the following bases in order of increasing strength: NH₃, PH₃, H₂O and H₂S.

Elements Compounds

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Structure of the Atom

The Covalent Bond

Ionic and Metallic Bonds

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Exam 11: Acids and Bases

What is the conjugate acid of hydrogen carbonate ion, HCO3 - ?

When would the pH of a solution prepared by adding sodium formate to formic acid be equal to the pKa of formic acid, HCO2H?

What is the pH of a solution that is 0.01 M in CH3NH2 and 0.1 M in CH3NH3+? CH3NH2(aq) + H2O(l) CH3NH3+(aq) + OH-(aq) Kb = 4.4 x 10-4

Which of the following would be the strongest Brønsted base?

Which of the following is the best Lewis structure for carbonic acid (H2CO3)?

A diprotic acid, H2A, has the following dissociation constants: Ka1 = 2.1 x 10-7 and Ka2 = 4.3 x 10-13. The H3O+ ion concentration when this acid is dissolved in water is

Which of the following acids would have the strongest conjugate base?

The salt NaF is dissolved in water. Which of the following relationships would be true for the species in solution?

Explain the following observation: Water becomes acidic when CO2 is bubbled into it.

For a weak diprotic acid, H2A, for which Ka1 = 2.1 x 10-7 and Ka2 = 4.3 x 10-13 the A2- ion concentration at equilibrium will be:

Which of the following compounds can act as either a Brønsted acid or a Brønsted base? (I) NaHCO3 (II) Na2CO3 (III) H2CO3 (IV) CO2 (V) H2O

Which of the following would you expect to be the strongest acid?

What is the hydroxide ion concentration in a pH = 5.14 solution?

What is the pH of a 0.10 M H2CO3 solution? (H2CO3: Ka1 = 4.2 x 10-7, Ka2 = 4.8 x 10-11)

Ethanol (CH3CH2OH), like water, can behave both as an acid or as a base. Which of the following structures corresponds to the Brønsted conjugate acid and conjugate base of ethanol?

Calculate the approximate pH of a 0.10 M lactic acid solution. (Ka = 8.4 x 10-4)

Determine the [OH ] for an aqueous solution at 25 C with a pH of 4.80.

Use the following acid-dissociation equilibrium constants for -0.5 M solutions of NaA, NaB, NaC, and NaD are prepared. Which solution is the most basic?

Which of the following structural factors is primarily responsible for H2AsO4 - being a stronger acid than HAsO42 - ?

Arrange the following bases in order of increasing strength: NH3, PH3, H2O and H2S.

Elements Compounds

The Mole

Structure of the Atom

The Covalent Bond

Ionic and Metallic Bonds

Gases

Making and Breaking of Bonds

Liquids and Solutions

Solids

An Introduction to Kinetics and Equilibrium

Oxidation-Reduction Reactions

Chemical Thermodynamics

Kinetics

Nuclear Chemistry

Organic Chemistry

Filters

What is the conjugate acid of hydrogen carbonate ion, HCO₃ ^- ?

When would the pH of a solution prepared by adding sodium formate to formic acid be equal to the pK_a of formic acid, HCO₂H?

What is the pH of a solution that is 0.01 M in CH₃NH₂ and 0.1 M in CH₃NH₃⁺? CH₃NH₂(aq) + H₂O(l) CH₃NH₃⁺(aq) + OH^-(aq) K_b = 4.4 x 10^-4

Which of the following is the best Lewis structure for carbonic acid (H₂CO₃)?

A diprotic acid, H₂A, has the following dissociation constants: K_a1 = 2.1 x 10^-7 and K_a2 = 4.3 x 10^-13. The H₃O⁺ ion concentration when this acid is dissolved in water is

Explain the following observation: Water becomes acidic when CO₂ is bubbled into it.

For a weak diprotic acid, H₂A, for which K_a1 = 2.1 x 10^-7 and K_a2 = 4.3 x 10^-13 the A^2- ion concentration at equilibrium will be:

Which of the following compounds can act as either a Brønsted acid or a Brønsted base? (I) NaHCO₃ (II) Na₂CO₃ (III) H₂CO₃ (IV) CO₂ (V) H₂O

What is the pH of a 0.10 M H₂CO₃ solution? (H₂CO₃: K_a1 = 4.2 x 10^-7, K_a2 = 4.8 x 10^-11)

Ethanol (CH₃CH₂OH), like water, can behave both as an acid or as a base. Which of the following structures corresponds to the Brønsted conjugate acid and conjugate base of ethanol?

Calculate the approximate pH of a 0.10 M lactic acid solution. (K_a = 8.4 x 10^-4)

Which of the following structural factors is primarily responsible for H₂AsO₄ ^- being a stronger acid than HAsO₄² ^- ?

Arrange the following bases in order of increasing strength: NH₃, PH₃, H₂O and H₂S.