Question 1

If an acid,HA,is 14.7% dissociated in a 1.0 M solution,what is the Ka for this acid?

Accepted Answer

A) 1.7 $\times$ 10-1 
B) 2.5 $\times$ 10-2 
C) 1.5 $\times$ 10-1 
D) 3.9 $\times$ 101 
E) none of these 
A) 1.7 $\times$ 10-1 
B) 2.5 $\times$ 10-2 
C) 1.5 $\times$ 10-1 
D) 3.9 $\times$ 101 
E) none of these

Question 2

The pH of a 0.150 M solution of a weak base is 10.98.Calculate the pH of a 0.0603 M solution of the base.

Accepted Answer

A) 3.22 
B) 10.78 
C) 7.57 
D) 6.43 
E) none of these 
A) 3.22 
B) 10.78 
C) 7.57 
D) 6.43 
E) none of these

Question 3

Calculate the [H+] in 1.0 M solution of Na2CO3 (for H2CO3,Ka1 = 4.3 $\times$ 10-7;Ka2 = 5.6 $\times$ 10-11).

Accepted Answer

A) 7.5 $\times$10-6 M 
B) 6.6 $\times$10-4 M 
C) 1.3 $\times$ 10-2 M 
D) 7.5 $\times$ 10-13 M 
E) none of these 
A) 7.5 $\times$10-6 M 
B) 6.6 $\times$10-4 M 
C) 1.3 $\times$ 10-2 M 
D) 7.5 $\times$ 10-13 M 
E) none of these

Question 4

Calculate the pOH of a 0.32 M solution of Ba(OH)2.

Accepted Answer

A) 0.49 
B) 0.19 
C) 13.81 
D) 13.51 
E) none of these 
A) 0.49 
B) 0.19 
C) 13.81 
D) 13.51 
E) none of these

Question 5

Calculate the pH of a 5.7 M solution of aniline (C6H5NH2;Kb = 3.8 $\times$ 10-10):

Accepted Answer

A) 4.33 
B) 9.67 
C) 5.34 
D) 8.66 
E) none of these 
A) 4.33 
B) 9.67 
C) 5.34 
D) 8.66 
E) none of these

Question 6

The sodium salt,NaA,of a weak acid is dissolved in water;no other substance is added.Which of these statements (to a close approximation)is true?

Accepted Answer

A) [H+] = [A-] 
B) [H+] = [OH-] 
C) [A-] = [OH-] 
D) [HA] = [OH-] 
E) none of these 
A) [H+] = [A-] 
B) [H+] = [OH-] 
C) [A-] = [OH-] 
D) [HA] = [OH-] 
E) none of these

Question 7

How many moles of benzoic acid,a monoprotic acid with Ka = 6.4 $\times$ 10-5,must be dissolved in 250.mL of H2O to produce a solution with pH = 2.04?

Accepted Answer

A) 1.3 
B) 0.00228 
C) 0.32 
D) 36 
E) none of these 
A) 1.3 
B) 0.00228 
C) 0.32 
D) 36 
E) none of these

Question 8

A 0.186 M solution of the salt NaA has a pH of 8.40.Calculate the Ka value of the acid HA.

Accepted Answer

A) 3.4 $\times$ 10-11 
B) 7.4 $\times$ 10-10 
C) 2.9 $\times$ 10-4 
D) 1.2 $\times$ 102 
E) none of these 
A) 3.4 $\times$ 10-11 
B) 7.4 $\times$ 10-10 
C) 2.9 $\times$ 10-4 
D) 1.2 $\times$ 102 
E) none of these

Question 9

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

Accepted Answer

basic
CaO(s)+ H<sub>

Question 10

Determine the percent dissociation of a 0.18 M solution of hypochlorous acid,HClO.The Ka for the acid is 3.5 $\times$ 10-8.

Accepted Answer

A) 3.5 $\times$ 10-6 % 
B) 6.3 $\times$ 10-9 % 
C) 7.9 $\times$ 10-3 % 
D) 4.4 $\times$ 10-2 % 
E) 1.1 $\times$10-2 % 
A) 3.5 $\times$ 10-6 % 
B) 6.3 $\times$ 10-9 % 
C) 7.9 $\times$ 10-3 % 
D) 4.4 $\times$ 10-2 % 
E) 1.1 $\times$10-2 %

Question 11

Consider a solution made by mixing HCN (Ka = 6.2 $\times$ 10-10)with HC2H3O2 (Ka = 1.8 $\times$ 10-5)in aqueous solution.What are the major species in solution?

Accepted Answer

A) H+,CN-,H+,C2H3O2-,H2O 
B) HCN,H+,C2H3O2-,H2O 
C) H+,CN-,HC2H3O2,H2O 
D) H+,CN-,H+,C2H3O2-,OH-,H2O 
E) HCN,HC2H3O2,H2O 
A) H+,CN-,H+,C2H3O2-,H2O 
B) HCN,H+,C2H3O2-,H2O 
C) H+,CN-,HC2H3O2,H2O 
D) H+,CN-,H+,C2H3O2-,OH-,H2O 
E) HCN,HC2H3O2,H2O

Question 12

You have 100.0 mL of a solution of hydrochloric acid that has a pH of 3.00.You add 100.0 mL of water to this solution.What is the resulting pH of the solution?

Accepted Answer

A) The pH = 5.00 (the average of 3.00 and 7.00). 
B) The pH = 10.00 (3.00 + 7.00 = 10.00). 
C) The pH = 3.00 (water is neutral and does not affect the pH). 
D) None of the above is correct,but the pH must be greater than 3.00. 
E) None of the above is correct,but the pH must be less than 3.00. 
A) The pH = 5.00 (the average of 3.00 and 7.00). 
B) The pH = 10.00 (3.00 + 7.00 = 10.00). 
C) The pH = 3.00 (water is neutral and does not affect the pH). 
D) None of the above is correct,but the pH must be greater than 3.00. 
E) None of the above is correct,but the pH must be less than 3.00.

Question 13

Which of the following statements are true?

Accepted Answer

A) The pH of a strong acid is always lower than the pH of a weak acid. 
B) The pH of a solution can never be negative. 
C) For a conjugate acid-base pair,Ka = 1/Kb. 
D) At least two of the statements A-C are true. 
E) All of the statements A-C are false. 
A) The pH of a strong acid is always lower than the pH of a weak acid. 
B) The pH of a solution can never be negative. 
C) For a conjugate acid-base pair,Ka = 1/Kb. 
D) At least two of the statements A-C are true. 
E) All of the statements A-C are false.

Question 14

Consider the following reactions:
a)AlS1U1P13+S1S1P0 + 6HS1U1B12S1U1B0O   Al(OHS1U1B12S1U1B0)S1U1B16S1U1B0S1U1P13+S1S1P0
b)Al(OHS1U1B12S1U1B0)S1U1B16S1U1B0S1U1P13+S1S1P0   Al(OH)(OHS1U1B12S1U1B0)S1U1B15S1U1B0S1U1P12+S1S1P0 + HS1U1P1+S1S1P0
c)OClS1U1P1-S1S1P0 + HS1U1B12S1U1B0O   HOCl + OHS1U1P1-S1S1P0
d)CNS1U1P1-S1S1P0 + HS1U1P1+S1S1P0   HCN
e)none of these
-Which is associated with the definition of Kb?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) e 
A) a 
B) b 
C) c 
D) d 
E) e

Question 15

Calculate the pH of a 0.51 M solution of KOH.

Accepted Answer

A) 14.00 
B) 13.71 
C) 0.29 
D) 0.51 
E) none of these 
A) 14.00 
B) 13.71 
C) 0.29 
D) 0.51 
E) none of these

Question 16

As water is heated,its pH decreases.This means that:

Accepted Answer

A) The water is no longer neutral. 
B) The Kw value is decreasing. 
C) The water has a lower [OH-] than cooler water. 
D) The dissociation of water is an endothermic process. 
E) None of these. 
A) The water is no longer neutral. 
B) The Kw value is decreasing. 
C) The water has a lower [OH-] than cooler water. 
D) The dissociation of water is an endothermic process. 
E) None of these.

Question 17

The hydrogen sulfate or bisulfate ion HSO4- can act as either an acid or a base in water solution.In which of the following equations does HSO4- act as an acid?

Accepted Answer

A) HSO4- + H2O $\to$H2SO4 + OH- 
B) HSO4- + H3O+ $\to$ SO3 + 2H2O 
C) HSO4- + OH- $\to$H2SO4 + O2- 
D) HSO4- + H2O $\to$ SO42- + H3O+ 
E) none of these 
A) HSO4- + H2O $\to$H2SO4 + OH- 
B) HSO4- + H3O+ $\to$ SO3 + 2H2O 
C) HSO4- + OH- $\to$H2SO4 + O2- 
D) HSO4- + H2O $\to$ SO42- + H3O+ 
E) none of these

Question 18

A solution in which the pOH is 12.1 would be described as

Accepted Answer

A) very acidic 
B) slightly acidic 
C) neutral 
D) very basic 
E) slightly basic 
A) very acidic 
B) slightly acidic 
C) neutral 
D) very basic 
E) slightly basic

Question 19

Which of the following is the equilibrium constant expression for the dissociation of the weak acid HOCl?

Accepted Answer

A) K =   
B) K = [H+][OCl-] 
C) K =   
D) K =   
E) none of these 
A) K =   
B) K = [H+][OCl-] 
C) K =   
D) K =   
E) none of these

Question 20

Select the answer that best describes an aqueous solution made from each of the following substances:
-solid ammonium acetate (NH4C2H3O2).For NH4+,Ka = 5.6$\times$ 10-10;for C2H3O2-,Kb = 5.6 $\times$ 10-10.

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)

Exam 14: Acids and Bases

If an acid,HA,is 14.7% dissociated in a 1.0 M solution,what is the Ka for this acid?

The pH of a 0.150 M solution of a weak base is 10.98.Calculate the pH of a 0.0603 M solution of the base.

Calculate the [H+] in 1.0 M solution of Na2CO3 (for H2CO3,Ka1 = 4.3 ×\times× 10-7;Ka2 = 5.6 ×\times× 10-11).

Calculate the pOH of a 0.32 M solution of Ba(OH)2.

Calculate the pH of a 5.7 M solution of aniline (C6H5NH2;Kb = 3.8 ×\times× 10-10):

The sodium salt,NaA,of a weak acid is dissolved in water;no other substance is added.Which of these statements (to a close approximation)is true?

How many moles of benzoic acid,a monoprotic acid with Ka = 6.4 ×\times× 10-5,must be dissolved in 250.mL of H2O to produce a solution with pH = 2.04?

A 0.186 M solution of the salt NaA has a pH of 8.40.Calculate the Ka value of the acid HA.

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

Determine the percent dissociation of a 0.18 M solution of hypochlorous acid,HClO.The Ka for the acid is 3.5 ×\times× 10-8.

Consider a solution made by mixing HCN (Ka = 6.2 ×\times× 10-10)with HC2H3O2 (Ka = 1.8 ×\times× 10-5)in aqueous solution.What are the major species in solution?

You have 100.0 mL of a solution of hydrochloric acid that has a pH of 3.00.You add 100.0 mL of water to this solution.What is the resulting pH of the solution?

Which of the following statements are true?

Consider the following reactions: a)Al3+ + 6H2O Al(OH2)63+ b)Al(OH2)63+ Al(OH)(OH2)52+ + H+ c)OCl- + H2O HOCl + OH- d)CN- + H+ HCN e)none of these -Which is associated with the definition of Kb?

Calculate the pH of a 0.51 M solution of KOH.

As water is heated,its pH decreases.This means that:

The hydrogen sulfate or bisulfate ion HSO4- can act as either an acid or a base in water solution.In which of the following equations does HSO4- act as an acid?

A solution in which the pOH is 12.1 would be described as

Which of the following is the equilibrium constant expression for the dissociation of the weak acid HOCl?

Select the answer that best describes an aqueous solution made from each of the following substances: -solid ammonium acetate (NH4C2H3O2).For NH4+,Ka = 5.6 ×\times× 10-10;for C2H3O2-,Kb = 5.6 ×\times× 10-10.

Chemical Foundations

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Bonding: General Concepts

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Transition Metals and Coordination Chemistry

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Filters

If an acid,HA,is 14.7% dissociated in a 1.0 M solution,what is the K_a for this acid?

Calculate the [H⁺] in 1.0 M solution of Na₂CO₃ (for H₂CO₃,K_a1= 4.3 $\times$ 10^-⁷;K_a2= 5.6 $\times$ 10^-¹¹).

Calculate the pOH of a 0.32 M solution of Ba(OH)₂.

Calculate the pH of a 5.7 M solution of aniline (C₆H₅NH₂;K_b = 3.8 $\times$ 10^-¹⁰):

How many moles of benzoic acid,a monoprotic acid with K_a = 6.4 $\times$ 10^-⁵,must be dissolved in 250.mL of H₂O to produce a solution with pH = 2.04?

A 0.186 M solution of the salt NaA has a pH of 8.40.Calculate the K_a value of the acid HA.

Determine the percent dissociation of a 0.18 M solution of hypochlorous acid,HClO.The K_a for the acid is 3.5 $\times$ 10^-⁸.

Consider a solution made by mixing HCN (K_a = 6.2 $\times$ 10^-¹⁰)with HC₂H₃O₂ (K_a = 1.8 $\times$ 10^-⁵)in aqueous solution.What are the major species in solution?

Consider the following reactions: a)Al³⁺ + 6H₂O Al(OH₂)₆³⁺ b)Al(OH₂)₆³⁺ Al(OH)(OH₂)₅²⁺ + H⁺ c)OCl^- + H₂O HOCl + OH^- d)CN^- + H⁺ HCN e)none of these -Which is associated with the definition of K_b?

The hydrogen sulfate or bisulfate ion HSO₄^- can act as either an acid or a base in water solution.In which of the following equations does HSO₄^- act as an acid?

Select the answer that best describes an aqueous solution made from each of the following substances: -solid ammonium acetate (NH₄C₂H₃O₂).For NH₄⁺,K_a = 5.6 $\times$ 10^-¹⁰;for C₂H₃O₂^-,K_b = 5.6 $\times$ 10^-¹⁰.