Question 1

Both H2O and OH- can act as a Brønsted acid and a Brønsted base but not as a Lewis acid.

Accepted Answer

A) True 
 B)False

Question 2

Which of the following is the conjugate acid of H2PO4-?

Accepted Answer

A) PO43- 
B) OH- 
C) H3PO4 
D) H2PO4- 
E) HPO42- 
A) PO43- 
B) OH- 
C) H3PO4 
D) H2PO4- 
E) HPO42-

Question 3

When sulfur trioxide dissolves in water,sulfuric acid is produced.An intermediate in the reaction is H2O-SO3.In the reaction of the intermediate to produce sulfuric acid,

Accepted Answer

A) water acts both as an acid and a base. 
B) water acts as a proton donor only. 
C) water acts as a proton acceptor only. 
D) the intermediate undergoes an intramolecular rearrangement to form the product. 
A) water acts both as an acid and a base. 
B) water acts as a proton donor only. 
C) water acts as a proton acceptor only. 
D) the intermediate undergoes an intramolecular rearrangement to form the product.

Question 4

The pH of 0.80 M benzenesulfonic acid is 0.51.What is the percentage ionization of benzenesulfonic acid?

Accepted Answer

A) 25% 
B) 39% 
C) 51% 
D) 5.0% 
E) 64% 
A) 25% 
B) 39% 
C) 51% 
D) 5.0% 
E) 64%

Question 5

If pKa1 and pKa2 for H2CO3 are 6.37 and 10.25,respectively,calculate the equilibrium constant for the reaction below: H2CO3(aq)+ 2H2O(l)↔ 2H3O+(aq)+ CO32-(aq)

Accepted Answer

A) 4.1 * 10-11  
B) 4.3 * 10-7  
C) 5.6 *10-11  
D) 2.3 * 10-8  
E) 2.4 * 10-17  
A) 4.1 * 10-11  
B) 4.3 * 10-7  
C) 5.6 *10-11  
D) 2.3 * 10-8  
E) 2.4 * 10-17

Question 6

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right.   Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

Accepted Answer

A) NaHSO4  
B) KF 
C) HNO2  
D) CH3NH2  
E) (CH3)3NHCl 
A) NaHSO4  
B) KF 
C) HNO2  
D) CH3NH2  
E) (CH3)3NHCl

Question 7

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right.   Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

Accepted Answer

A) NH4Cl 
B) NaCN 
C) Al2(SO4)3  
D) CH3NH2  
E) CH3COOH 
A) NH4Cl 
B) NaCN 
C) Al2(SO4)3  
D) CH3NH2  
E) CH3COOH

Question 8

If $\alpha$(HSO3-)= 0.45 at pH 7.0,what are $\alpha$(H2SO3)and $\alpha$(SO32-)at this pH? For H2SO3,pKa1 and pKa2 are 1.81 and 6.91,respectively.

Accepted Answer

A) $\alpha$(H2SO3)= 0.225 and $\alpha$(SO32-)= 0.55 
B) $\alpha$(H2SO3)= 0.55 and $\alpha$(SO32-)~ 0 
C) $\alpha$(H2SO3)~ 0 and $\alpha$(SO32-)= 0.225 
D) $\alpha$(H2SO3)~ 0 and $\alpha$SO32-)= 0.55 
E) $\alpha$(H2SO3)= 0.45 and $\alpha$(SO32-)= 0.55 
A) $\alpha$(H2SO3)= 0.225 and $\alpha$(SO32-)= 0.55 
B) $\alpha$(H2SO3)= 0.55 and $\alpha$(SO32-)~ 0 
C) $\alpha$(H2SO3)~ 0 and $\alpha$(SO32-)= 0.225 
D) $\alpha$(H2SO3)~ 0 and $\alpha$SO32-)= 0.55 
E) $\alpha$(H2SO3)= 0.45 and $\alpha$(SO32-)= 0.55

Question 9

If the pKa1 = 1.81,and pKa2 = 6.91 for a 0.05 M solution of H2SeO3,what is its [H+]?

Accepted Answer

A) 0.015 M 
B) 0.021 M 
C) 0.025 M 
D) 0.029 M 
E) 0.050 M 
A) 0.015 M 
B) 0.021 M 
C) 0.025 M 
D) 0.029 M 
E) 0.050 M

Question 10

The pH of a 0.0050 M aqueous solution of calcium hydroxide is

Accepted Answer

A) 11.40 
B) 2.00 
C) 12.00 
D) 12.70 
E) 11.70 
A) 11.40 
B) 2.00 
C) 12.00 
D) 12.70 
E) 11.70

Question 11

If the value of Kb for pyridine is 1.8 * 10-9,calculate the equilibrium constant for C5H5NH+(aq)+ H2O(l)↔ C5H5N(aq)+ H3O+(aq)

Accepted Answer

A) -1.8 * 10-9  
B) 1.8 *10-16  
C) 5.6 * 108  
D) 1.8 * 10-9  
E) 5.6 * 10-6  
A) -1.8 * 10-9  
B) 1.8 *10-16  
C) 5.6 * 108  
D) 1.8 * 10-9  
E) 5.6 * 10-6

Question 12

Estimate the pH of 0.10 M Na2HPO4(aq)given pKa1 = 2.12,pKa2 = 7.21,and pKa3 = 12.68 for phosphoric acid.

Accepted Answer

A) 12.68 
B) 9.94 
C) 7.40 
D) 4.67 
E) 2.12 
A) 12.68 
B) 9.94 
C) 7.40 
D) 4.67 
E) 2.12

Question 13

The equation that represents Ka2 for sulfurous acid is

Accepted Answer

A) HSO3-(aq)+ H2O(l)↔ H2SO3(aq)+ OH-(aq). 
B) HSO3-(aq)+ H2O(l)↔ SO32-(aq)+ H3O+(aq). 
C) H2SO3(aq)+ 2H2O(l)↔ SO32-(aq)+ 2H3O+(aq). 
D) SO32-(aq)+ H2O(l)↔ HSO3-(aq)+ OH-(aq). 
E) H2SO3(aq)+ H2O(l)↔ HSO3-(aq)+ H3O+(aq). 
A) HSO3-(aq)+ H2O(l)↔ H2SO3(aq)+ OH-(aq). 
B) HSO3-(aq)+ H2O(l)↔ SO32-(aq)+ H3O+(aq). 
C) H2SO3(aq)+ 2H2O(l)↔ SO32-(aq)+ 2H3O+(aq). 
D) SO32-(aq)+ H2O(l)↔ HSO3-(aq)+ OH-(aq). 
E) H2SO3(aq)+ H2O(l)↔ HSO3-(aq)+ H3O+(aq).

Question 14

Estimate the pH of 10-7 M KOH(aq).

Accepted Answer

A) 6.9 
B) 9 
C) 13 
D) 7.2 
E) 7.0 
A) 6.9 
B) 9 
C) 13 
D) 7.2 
E) 7.0

Question 15

Which of the following aqueous solutions gives a pH greater than 7?

Accepted Answer

A) 10-8 M NH4Cl 
B) None of the solutions gives a pH greater than 7. 
C) 10-8 M CH3COOH 
D) 10-8 M HCl 
E) 10-8 M HCOOH 
A) 10-8 M NH4Cl 
B) None of the solutions gives a pH greater than 7. 
C) 10-8 M CH3COOH 
D) 10-8 M HCl 
E) 10-8 M HCOOH

Question 16

In liquid ammonia,the acid HB is a strong acid if it is a weaker proton donor than NH4+.

Accepted Answer

A) True 
 B)False

Question 17

Calculate the equilibrium concentration of sulfurous acid in a solution labeled "0.100 M H2SO3(aq)" if pKa1 = 1.81,and pKa2 = 6.91.

Accepted Answer

A) 0.068 M 
B) 0.015 M 
C) 0.100 M 
D) 0.050 M 
E) 0.032 M 
A) 0.068 M 
B) 0.015 M 
C) 0.100 M 
D) 0.050 M 
E) 0.032 M

Question 18

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right.   Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

Accepted Answer

A) NaI 
B) HCOOH 
C) C6H5NH2  
D) CH3NH3Cl 
E) NaClO 
A) NaI 
B) HCOOH 
C) C6H5NH2  
D) CH3NH3Cl 
E) NaClO

Question 19

Calculate the equilibrium constant for the reaction HSS1U1P1-S1S1P0(aq)+ H2O(l)↔ H2S(aq)+ OH-(aq),
Given Ka1 = 1.3 * 10-7 and Ka2 = 7.1 * 10-15 for H2S.

Accepted Answer

A) 1.3 * 10-7  
B) 7.7 *10-8  
C) 9.2 *10-22  
D) 7.1 * 10-15  
E) 1.4 
A) 1.3 * 10-7  
B) 7.7 *10-8  
C) 9.2 *10-22  
D) 7.1 * 10-15  
E) 1.4

Question 20

Is a 0.1 M aqueous solution of HPO42-acidic,basic,or neutral? Prove your answer using the appropriate equilibrium constants.

Accepted Answer

basic,K_b (HPO₄

Both H₂O and OH^- can act as a Brønsted acid and a Brønsted base but not as a Lewis acid.

Which of the following is the conjugate acid of H₂PO₄^-?

When sulfur trioxide dissolves in water,sulfuric acid is produced.An intermediate in the reaction is H₂O-SO₃.In the reaction of the intermediate to produce sulfuric acid,

The pH of 0.80 M benzenesulfonic acid is 0.51.What is the percentage ionization of benzenesulfonic acid?

If pK_a1 and pK_a2 for H₂CO₃ are 6.37 and 10.25,respectively,calculate the equilibrium constant for the reaction below: H₂CO₃(aq)+ 2H₂O(l)↔ 2H₃O⁺(aq)+ CO₃²^-(aq)

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right. Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right. Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

If $\alpha$ (HSO₃^-)= 0.45 at pH 7.0,what are $\alpha$ (H₂SO₃)and $\alpha$ (SO₃²^-)at this pH? For H₂SO₃,pK_a1 and pK_a2 are 1.81 and 6.91,respectively.

If the pK_a1 = 1.81,and pK_a2 = 6.91 for a 0.05 M solution of H₂SeO₃,what is its [H⁺]?

The pH of a 0.0050 M aqueous solution of calcium hydroxide is

If the value of K_b for pyridine is 1.8 * 10^-9,calculate the equilibrium constant for C₅H₅NH⁺(aq)+ H₂O(l)↔ C₅H₅N(aq)+ H₃O⁺(aq)

Estimate the pH of 0.10 M Na₂HPO₄(aq)given pK_a1 = 2.12,pK_a2 = 7.21,and pK_a3 = 12.68 for phosphoric acid.

The equation that represents K_a2 for sulfurous acid is

Estimate the pH of 10^-7 M KOH(aq).

Which of the following aqueous solutions gives a pH greater than 7?

In liquid ammonia,the acid HB is a strong acid if it is a weaker proton donor than NH₄⁺.

Calculate the equilibrium concentration of sulfurous acid in a solution labeled "0.100 M H₂SO₃(aq)" if pK_a1 = 1.81,and pK_a2 = 6.91.

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right. Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

Calculate the equilibrium constant for the reaction HS^-(aq)+ H₂O(l)↔ H₂S(aq)+ OH^-(aq), Given K_a1 = 1.3 * 10^-7 and K_a2 = 7.1 * 10^-15 for H₂S.

Is a 0.1 M aqueous solution of HPO₄^2-acidic,basic,or neutral? Prove your answer using the appropriate equilibrium constants.

The Quantum World

Quantum Mechanics in Action: Atoms

Chemical Bonds

Molecular Shape and Structure

The Properties of Gases

Liquids and Solids

Inorganic Materials

Thermodynamics: The First Law

Thermodynamics: The Second and Third Laws

Physical Equilibria

Chemical Equilibria

Aqueous Equilibria

Electrochemistry

Chemical Kinetics

The Elements: the Main Group Elements

The Elements: The D Block

Nuclear Chemistry

Organic Chemistry I

Organic Chemistry II

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Exam 12: Acids and Bases

Both H2O and OH- can act as a Brønsted acid and a Brønsted base but not as a Lewis acid.

Which of the following is the conjugate acid of H2PO4-?

When sulfur trioxide dissolves in water,sulfuric acid is produced.An intermediate in the reaction is H2O-SO3.In the reaction of the intermediate to produce sulfuric acid,

The pH of 0.80 M benzenesulfonic acid is 0.51.What is the percentage ionization of benzenesulfonic acid?

If pKa1 and pKa2 for H2CO3 are 6.37 and 10.25,respectively,calculate the equilibrium constant for the reaction below: H2CO3(aq)+ 2H2O(l)↔ 2H3O+(aq)+ CO32-(aq)

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right. Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right. Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

If α\alphaα (HSO3-)= 0.45 at pH 7.0,what are α\alphaα (H2SO3)and α\alphaα (SO32-)at this pH? For H2SO3,pKa1 and pKa2 are 1.81 and 6.91,respectively.

If the pKa1 = 1.81,and pKa2 = 6.91 for a 0.05 M solution of H2SeO3,what is its [H+]?

The pH of a 0.0050 M aqueous solution of calcium hydroxide is

If the value of Kb for pyridine is 1.8 * 10-9,calculate the equilibrium constant for C5H5NH+(aq)+ H2O(l)↔ C5H5N(aq)+ H3O+(aq)

Estimate the pH of 0.10 M Na2HPO4(aq)given pKa1 = 2.12,pKa2 = 7.21,and pKa3 = 12.68 for phosphoric acid.

The equation that represents Ka2 for sulfurous acid is

Estimate the pH of 10-7 M KOH(aq).

Which of the following aqueous solutions gives a pH greater than 7?

In liquid ammonia,the acid HB is a strong acid if it is a weaker proton donor than NH4+.

Calculate the equilibrium concentration of sulfurous acid in a solution labeled "0.100 M H2SO3(aq)" if pKa1 = 1.81,and pKa2 = 6.91.

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right. Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

Calculate the equilibrium constant for the reaction HS-(aq)+ H2O(l)↔ H2S(aq)+ OH-(aq), Given Ka1 = 1.3 * 10-7 and Ka2 = 7.1 * 10-15 for H2S.

Is a 0.1 M aqueous solution of HPO42-acidic,basic,or neutral? Prove your answer using the appropriate equilibrium constants.

The Quantum World

Quantum Mechanics in Action: Atoms

Chemical Bonds

Molecular Shape and Structure

The Properties of Gases

Liquids and Solids

Inorganic Materials

Thermodynamics: The First Law

Thermodynamics: The Second and Third Laws

Physical Equilibria

Chemical Equilibria

Aqueous Equilibria

Electrochemistry

Chemical Kinetics

The Elements: the Main Group Elements

The Elements: The D Block

Nuclear Chemistry

Organic Chemistry I

Organic Chemistry II

Filters

Both H₂O and OH^- can act as a Brønsted acid and a Brønsted base but not as a Lewis acid.

Which of the following is the conjugate acid of H₂PO₄^-?

When sulfur trioxide dissolves in water,sulfuric acid is produced.An intermediate in the reaction is H₂O-SO₃.In the reaction of the intermediate to produce sulfuric acid,

If pK_a1 and pK_a2 for H₂CO₃ are 6.37 and 10.25,respectively,calculate the equilibrium constant for the reaction below: H₂CO₃(aq)+ 2H₂O(l)↔ 2H₃O⁺(aq)+ CO₃²^-(aq)

If $\alpha$ (HSO₃^-)= 0.45 at pH 7.0,what are $\alpha$ (H₂SO₃)and $\alpha$ (SO₃²^-)at this pH? For H₂SO₃,pK_a1 and pK_a2 are 1.81 and 6.91,respectively.

If the pK_a1 = 1.81,and pK_a2 = 6.91 for a 0.05 M solution of H₂SeO₃,what is its [H⁺]?

If the value of K_b for pyridine is 1.8 * 10^-9,calculate the equilibrium constant for C₅H₅NH⁺(aq)+ H₂O(l)↔ C₅H₅N(aq)+ H₃O⁺(aq)

Estimate the pH of 0.10 M Na₂HPO₄(aq)given pK_a1 = 2.12,pK_a2 = 7.21,and pK_a3 = 12.68 for phosphoric acid.

The equation that represents K_a2 for sulfurous acid is

Estimate the pH of 10^-7 M KOH(aq).

In liquid ammonia,the acid HB is a strong acid if it is a weaker proton donor than NH₄⁺.

Calculate the equilibrium concentration of sulfurous acid in a solution labeled "0.100 M H₂SO₃(aq)" if pK_a1 = 1.81,and pK_a2 = 6.91.

Calculate the equilibrium constant for the reaction HS^-(aq)+ H₂O(l)↔ H₂S(aq)+ OH^-(aq), Given K_a1 = 1.3 * 10^-7 and K_a2 = 7.1 * 10^-15 for H₂S.

Is a 0.1 M aqueous solution of HPO₄^2-acidic,basic,or neutral? Prove your answer using the appropriate equilibrium constants.