Question 1

The pain killer morphine is a weak base when added to water.The Kb is 1.6 $\times$ 10-6.What is the pH of a 4.33 $\times$10-3 M solution of morphine?

Accepted Answer

A) 4.08 
B) 9.92 
C) 5.84 
D) 9.77 
E) none of these 
A) 4.08 
B) 9.92 
C) 5.84 
D) 9.77 
E) none of these

Question 2

Acetic acid, (HC2H3O2)is a weak acid (Ka = 1.8 $\times$ 10-5).Calculate the pH of a 15.1 M HC2H3O2 solution.

Accepted Answer

A) -1.18 
B) 3.57 
C) 1.78 
D) 1.18 
E) 12.22 
A) -1.18 
B) 3.57 
C) 1.78 
D) 1.18 
E) 12.22

Question 3

When 2.5 $\times$ 10-2 mol of nicotinic acid (a monoprotic acid)is dissolved in 350 mL of water,the pH is 3.05.Calculate the Ka of nicotinic acid.

Accepted Answer

A) 1.3 $\times$10-2 
B) 1.1 $\times$ 10-5 
C) 7.1 $\times$ 10-2 
D) 3.3 $\times$ 10-5 
E) none of these 
A) 1.3 $\times$10-2 
B) 1.1 $\times$ 10-5 
C) 7.1 $\times$ 10-2 
D) 3.3 $\times$ 10-5 
E) none of these

Question 4

Calculate the pH of a 0.031 M strong acid solution.

Accepted Answer

A) -1.51 
B) 1.51 
C) 12.49 
D) 15.51 
E) none of these 
A) -1.51 
B) 1.51 
C) 12.49 
D) 15.51 
E) none of these

Question 5

In which of the following reactions does the H2PO4- ion act as an acid?

Accepted Answer

A) H3PO4 + H2O $\to$ H3O+ + H2PO4- 
B) H2PO4- + H2O $\to$ H3O+ + HPO42- 
C) H2PO4- + OH- $\to$ H3PO4 + O2- 
D) The ion cannot act as an acid. 
E) Two of these. 
A) H3PO4 + H2O $\to$ H3O+ + H2PO4- 
B) H2PO4- + H2O $\to$ H3O+ + HPO42- 
C) H2PO4- + OH- $\to$ H3PO4 + O2- 
D) The ion cannot act as an acid. 
E) Two of these.

Question 6

The dihydrogenphosphate ion,H2PO4-,has both a conjugate acid and a conjugate base.These are,respectively:

Accepted Answer

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

Question 7

What is the equilibrium concentration of PO43- in a 0.511 M solution of H3PO4(aq)? (Ka1 = 7.5 $\times$10-3,Ka2 = 6.2 $\times$ 10-8,Ka3 = 4.8 $\times$ 10-13)

Accepted Answer

A) 5.8 $\times$ 10-2 M 
B) 1.8 $\times$ 10-4 M 
C) 4.8 $\times$10-13 M 
D) 5.0 $\times$ 10-7 M 
E) 6.2 $\times$ 10-8 M 
A) 5.8 $\times$ 10-2 M 
B) 1.8 $\times$ 10-4 M 
C) 4.8 $\times$10-13 M 
D) 5.0 $\times$ 10-7 M 
E) 6.2 $\times$ 10-8 M

Question 8

The pH of a solution at 25°C in which [OH-] = 3.9 $\times$ 10-5 M is:

Accepted Answer

A) 4.41 
B) 3.90 
C) 9.59 
D) 4.80 
E) none of these 
A) 4.41 
B) 3.90 
C) 9.59 
D) 4.80 
E) none of these

Question 9

What volume of water must be added to 11.1 mL of a pH 2.0 solution of HNO3 in order to change the pH to 4.0?

Accepted Answer

A) 11.1 mL 
B) 89 mL 
C) 110 mL 
D) 1.10 $\times$ 103 mL 
E) 28 mL 
A) 11.1 mL 
B) 89 mL 
C) 110 mL 
D) 1.10 $\times$ 103 mL 
E) 28 mL

Question 10

Calculate the pH of a 2.3 $\times$ 10-3 M KOH solution.

Accepted Answer

A) 2.64 
B) 12.36 
C) 11.36 
D) 1.64 
E) 10.36 
A) 2.64 
B) 12.36 
C) 11.36 
D) 1.64 
E) 10.36

Question 11

Which of the following correctly labels the salts? HF (Ka = 7.2 $\times$ 10-4)
NH3 (Kb = 1.8 $\times$ 10-5)
HCN (Ka = 6.2 $\times$10-10)

Accepted Answer

A) NaCN = acidic,NH4F = basic,KCN = neutral 
B) NaCN = acidic,NH4F = neutral,KCN = basic 
C) NaCN = basic,NH4F = basic,KCN= neutral 
D) NaCN = basic,NH4F = neutral,KCN = basic 
E) NaCN = basic,NH4F = acidic,KCN = basic 
A) NaCN = acidic,NH4F = basic,KCN = neutral 
B) NaCN = acidic,NH4F = neutral,KCN = basic 
C) NaCN = basic,NH4F = basic,KCN= neutral 
D) NaCN = basic,NH4F = neutral,KCN = basic 
E) NaCN = basic,NH4F = acidic,KCN = basic

Question 12

For nitrous acid,HNO2,Ka = 4.0 $\times$10-4.Calculate the pH of 0.27 M HNO2.

Accepted Answer

A) 1.98 
B) 0.57 
C) 3.97 
D) 12.02 
E) none of these 
A) 1.98 
B) 0.57 
C) 3.97 
D) 12.02 
E) none of these

Question 13

Select the answer that best describes an aqueous solution made from each of the following substances:
-solid sodium nitrate (NaNO3)

Accepted Answer

A) acidic 
B) basic 
C) neutral 
D) cannot tell 
E) none of these (A-
D)  
A) acidic 
B) basic 
C) neutral 
D) cannot tell 
E) none of these (A-
D)

Question 14

Which of the following species cannot act as a Lewis base?

Accepted Answer

A) Al3+ 
B) O2- 
C) OH- 
D) H2O 
E) H2O2 
A) Al3+ 
B) O2- 
C) OH- 
D) H2O 
E) H2O2

Question 15

A solution of 2.9 M weak acid is 0.52% ionized.What is the Ka value of this acid?

Accepted Answer

A) 7.9 $\times$ 10-5 
B) 1.5 
C) 1.5 $\times$ 10-2 
D) 5.2 $\times$ 10-3 
E) none of these 
A) 7.9 $\times$ 10-5 
B) 1.5 
C) 1.5 $\times$ 10-2 
D) 5.2 $\times$ 10-3 
E) none of these

Question 16

Which of the following indicates the most basic solution?

Accepted Answer

A) [H+] = 1 $\times$ 10-10 M 
B) pOH = 6.7 
C) [OH-] = 7 $\times$ 10-5 M 
D) pH = 4.2 
E) At least two of the solutions are equally basic. 
A) [H+] = 1 $\times$ 10-10 M 
B) pOH = 6.7 
C) [OH-] = 7 $\times$ 10-5 M 
D) pH = 4.2 
E) At least two of the solutions are equally basic.

Question 17

Determine whether the following oxides produce an acidic,basic,or neutral solution when dissolved in water:
-NO2

Accepted Answer

acidic 2NO₂(g)+ H

Question 18

The following question refers to a solution that contains 1.59 M hydrofluoric acid,HF (Ka = 7.2 $\times$ 10-4),and 3.00 M hydrocyanic acid,HCN (Ka = 6.2 $\times$ 10-10). What is the pH of this mixture of weak acids?

Accepted Answer

A) 1.47 
B) 2.94 
C) 4.50 
D) 9.01 
E) 12.53 
A) 1.47 
B) 2.94 
C) 4.50 
D) 9.01 
E) 12.53

Question 19

Which of the species below,when dissolved in H2O,will not produce a basic solution?

Accepted Answer

A) SO2 
B) NH3 
C) BaO 
D) Ba(OH)2 
E) none of these 
A) SO2 
B) NH3 
C) BaO 
D) Ba(OH)2 
E) none of these

Question 20

Which of the following species cannot act as a Lewis acid?

Accepted Answer

A) K+ 
B) Mg2+ 
C) Al3+ 
D) H+ 
E) H- 
A) K+ 
B) Mg2+ 
C) Al3+ 
D) H+ 
E) H-

Exam 14: Acids and Bases

The pain killer morphine is a weak base when added to water.The Kb is 1.6 ×\times× 10-6.What is the pH of a 4.33 ×\times× 10-3 M solution of morphine?

Acetic acid, (HC2H3O2)is a weak acid (Ka = 1.8 ×\times× 10-5).Calculate the pH of a 15.1 M HC2H3O2 solution.

When 2.5 ×\times× 10-2 mol of nicotinic acid (a monoprotic acid)is dissolved in 350 mL of water,the pH is 3.05.Calculate the Ka of nicotinic acid.

Calculate the pH of a 0.031 M strong acid solution.

In which of the following reactions does the H2PO4- ion act as an acid?

The dihydrogenphosphate ion,H2PO4-,has both a conjugate acid and a conjugate base.These are,respectively:

What is the equilibrium concentration of PO43- in a 0.511 M solution of H3PO4(aq)? (Ka1 = 7.5 ×\times× 10-3,Ka2 = 6.2 ×\times× 10-8,Ka3 = 4.8 ×\times× 10-13)

The pH of a solution at 25°C in which [OH-] = 3.9 ×\times× 10-5 M is:

What volume of water must be added to 11.1 mL of a pH 2.0 solution of HNO3 in order to change the pH to 4.0?

Calculate the pH of a 2.3 ×\times× 10-3 M KOH solution.

Which of the following correctly labels the salts? HF (Ka = 7.2 ×\times× 10-4) NH3 (Kb = 1.8 ×\times× 10-5) HCN (Ka = 6.2 ×\times× 10-10)

For nitrous acid,HNO2,Ka = 4.0 ×\times× 10-4.Calculate the pH of 0.27 M HNO2.

Select the answer that best describes an aqueous solution made from each of the following substances: -solid sodium nitrate (NaNO3)

Which of the following species cannot act as a Lewis base?

A solution of 2.9 M weak acid is 0.52% ionized.What is the Ka value of this acid?

Which of the following indicates the most basic solution?

Determine whether the following oxides produce an acidic,basic,or neutral solution when dissolved in water: -NO2

The following question refers to a solution that contains 1.59 M hydrofluoric acid,HF (Ka = 7.2 ×\times× 10-4),and 3.00 M hydrocyanic acid,HCN (Ka = 6.2 ×\times× 10-10). What is the pH of this mixture of weak acids?

Which of the species below,when dissolved in H2O,will not produce a basic solution?

Which of the following species cannot act as a Lewis acid?

Chemical Foundations

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Bonding: General Concepts

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Filters

The pain killer morphine is a weak base when added to water.The K_b is 1.6 $\times$ 10^-⁶.What is the pH of a 4.33 $\times$ 10^-³M solution of morphine?

Acetic acid, (HC₂H₃O₂)is a weak acid (K_a = 1.8 $\times$ 10^-⁵).Calculate the pH of a 15.1 M HC₂H₃O₂ solution.

When 2.5 $\times$ 10^-²mol of nicotinic acid (a monoprotic acid)is dissolved in 350 mL of water,the pH is 3.05.Calculate the K_a of nicotinic acid.

In which of the following reactions does the H₂PO₄^- ion act as an acid?

The dihydrogenphosphate ion,H₂PO₄^-,has both a conjugate acid and a conjugate base.These are,respectively:

What is the equilibrium concentration of PO₄³^- in a 0.511 M solution of H₃PO₄(aq)? (K_a1 = 7.5 $\times$ 10^-³,K_a2 = 6.2 $\times$ 10^-⁸,K_a3 = 4.8 $\times$ 10^-¹³)

The pH of a solution at 25°C in which [OH^-] = 3.9 $\times$ 10^-⁵M is:

What volume of water must be added to 11.1 mL of a pH 2.0 solution of HNO₃ in order to change the pH to 4.0?

Calculate the pH of a 2.3 $\times$ 10^-³M KOH solution.

Which of the following correctly labels the salts? HF (K_a= 7.2 $\times$ 10^-⁴) NH₃ (K_b = 1.8 $\times$ 10^-⁵) HCN (K_a= 6.2 $\times$ 10^-¹⁰)

For nitrous acid,HNO₂,K_a = 4.0 $\times$ 10^-⁴.Calculate the pH of 0.27 M HNO₂.

Select the answer that best describes an aqueous solution made from each of the following substances: -solid sodium nitrate (NaNO₃)

A solution of 2.9 M weak acid is 0.52% ionized.What is the K_a value of this acid?

Determine whether the following oxides produce an acidic,basic,or neutral solution when dissolved in water: -NO₂

The following question refers to a solution that contains 1.59 M hydrofluoric acid,HF (K_a = 7.2 $\times$ 10^-⁴),and 3.00 M hydrocyanic acid,HCN (K_a = 6.2 $\times$ 10^-¹⁰). What is the pH of this mixture of weak acids?

Which of the species below,when dissolved in H₂O,will not produce a basic solution?