Question 1

The value of Ka for a 0.250 M HCN solution having a pH of 4.956 is ________.

Accepted Answer

Question 2

Identify the set of Lewis acids.

Accepted Answer

A) BH3,BF3,Cu2+,CO2 
B) Cl-,OH-,NH3,H2O 
C) H3PO4,H2PO4-,HPO42-,PO43- 
D) CH3-,NH2-,OH-,F- 
A) BH3,BF3,Cu2+,CO2 
B) Cl-,OH-,NH3,H2O 
C) H3PO4,H2PO4-,HPO42-,PO43- 
D) CH3-,NH2-,OH-,F-

Question 3

Which one of the following is least able to behave as a Lewis base?

Accepted Answer

A) CH3NH2 
B) (CH3)2NH 
C) (CH3)3N 
D) (CH3)3NH+ 
A) CH3NH2 
B) (CH3)2NH 
C) (CH3)3N 
D) (CH3)3NH+

Question 4

What is the strongest acid among the following?

Accepted Answer

A) CH3CO2H 
B) ClCH2CO2H 
C) Cl2CHCO2H 
D) Cl3CCO2H 
A) CH3CO2H 
B) ClCH2CO2H 
C) Cl2CHCO2H 
D) Cl3CCO2H

Question 5

The compound BF3 can be described as a(n)________.

Accepted Answer

A) Arrhenius acid 
B) Br∅nsted-Lowry acid 
C) Lewis acid 
D) Lewis base 
A) Arrhenius acid 
B) Br∅nsted-Lowry acid 
C) Lewis acid 
D) Lewis base

Question 6

What is the pH of a 0.020 M Ba(OH)2 solution?

Accepted Answer

A) 1)40 
B) 1)70 
C) 12.30 
D) 12.60 
A) 1)40 
B) 1)70 
C) 12.30 
D) 12.60

Question 7

A solution with a hydroxide ion concentration of 4.15 × 10- 6 M is ________ and has a hydrogen ion concentration of ________.

Accepted Answer

A) acidic,2.41 × 10- 8 M 
B) acidic,2.41 × 10- 9 M 
C) basic,2.41 × 10- 8 M 
D) basic,2.41 × 10- 9 M 
A) acidic,2.41 × 10- 8 M 
B) acidic,2.41 × 10- 9 M 
C) basic,2.41 × 10- 8 M 
D) basic,2.41 × 10- 9 M

Question 8

What is the pH of a 0.10 M H2Se solution that has the stepwise dissociation constants
Ka1 = 1.3 × 10-4 and Ka2 = 1.0 × 10-11?

Accepted Answer

A) 2)44 
B) 3)89 
C) 4)89 
D) 5)50 
A) 2)44 
B) 3)89 
C) 4)89 
D) 5)50

Question 9

Acetic acid CH3COOH,has an acid dissociation constant of 1.8 × 10-5.What is the conjugate base of acetic acid and what is its base dissociation constant?

Accepted Answer

A) CH3C(OH)2+,5.6 × 104 
B) CH3C(OH)2+,5.6 × 10-10 
C) CH3COOH,5.6 × 10-10 
D) CH3CO2-,5.6 × 10-10 
A) CH3C(OH)2+,5.6 × 104 
B) CH3C(OH)2+,5.6 × 10-10 
C) CH3COOH,5.6 × 10-10 
D) CH3CO2-,5.6 × 10-10

Question 10

A 0.050 M solution of hydroxylamine,NH2OH,having Kb = 9.1 × 10-9 has a pH of ________.

Accepted Answer

Question 11

The following pictures represent solutions of three salts MA;water molecules have been omitted for clarity.Dotted spheres represent AS1U1P1yS1S1P0S1U1P1-S1S1P0 ions;gray spheres represent MS1U1P1x+S1S1P0 ions;black spheres represent oxygen atoms;and unshaded spheres represent hydrogen atoms.  
-Which picture represents an acidic salt?

Accepted Answer

A) (1) 
B) (2) 
C) (3) 
D) None of these 
A) (1) 
B) (2) 
C) (3) 
D) None of these

Question 12

How many grams of pyridine are there in 100 mL of an aqueous solution that has a pH of 9.00? The Kb for pyridine is 1.9 × 10-9 and the equation of interest is
C5H5N(aq)+ H2O(l)⇌ C5H5NH+(aq)+ OH-(aq).

Accepted Answer

A) 0)053 g 
B) 0)42 g 
C) 0)79 g 
D) 7)9 g 
A) 0)053 g 
B) 0)42 g 
C) 0)79 g 
D) 7)9 g

Question 13

Which of the following salts are acidic?

Accepted Answer

A) LiCl,NaCl,KCl 
B) NH4Cl,CuCl2,AlCl3 
C) NaCH3CO2,KCH3CO2,RbCH3CO2 
D) NaCl,NH4Cl,Na2CO3 
A) LiCl,NaCl,KCl 
B) NH4Cl,CuCl2,AlCl3 
C) NaCH3CO2,KCH3CO2,RbCH3CO2 
D) NaCl,NH4Cl,Na2CO3

Question 14

Which one of the following is not considered to be a Lewis base?

Accepted Answer

A) H2O 
B) NH3 
C) NH4+ 
D) Cl- 
A) H2O 
B) NH3 
C) NH4+ 
D) Cl-

Question 15

Phenobarbital is an antiepileptic drug with a water solubility of 4.3 × 10-3 M and pKa = 7.4.What is the pH and percent ionization of 4.3 × 10-3 M phenobarbital?

Accepted Answer

Question 16

Calculate the pH of a 0.020 M carbonic acid solution,H2CO3(aq),that has the stepwise dissociation constants Ka1 = 4.3 × 10-7 and Ka2 = 5.6 × 10-11.

Accepted Answer

A) 1)70 
B) 4)03 
C) 6)37 
D) 10.25 
A) 1)70 
B) 4)03 
C) 6)37 
D) 10.25

Question 17

Write a balanced equation for the dissociation of the Br∅nsted-Lowry acid HSO4- in water.

Accepted Answer

A) HSO4-(aq)+ H2O(l)⇌ H2SO4(aq)+ OH-(aq) 
B) HSO4-(aq)+ H2O(l)⇌ SO42-(aq)+ H3O+(aq) 
C) HSO4-(aq)+ H2O(l)⇌ SO32-(aq)+ OH-(aq) 
D) HSO4-(aq)+ H2O(l)⇌ SO3(g)+ OH-(aq)+ H2O(l) 
A) HSO4-(aq)+ H2O(l)⇌ H2SO4(aq)+ OH-(aq) 
B) HSO4-(aq)+ H2O(l)⇌ SO42-(aq)+ H3O+(aq) 
C) HSO4-(aq)+ H2O(l)⇌ SO32-(aq)+ OH-(aq) 
D) HSO4-(aq)+ H2O(l)⇌ SO3(g)+ OH-(aq)+ H2O(l)

Question 18

What is the hydroxide ion concentration of a lye solution that has a pH of 11.20?

Accepted Answer

A) 6)31 × 10-12 M 
B) 1)58 × 10-3 M 
C) 2)80 M 
D) 11.20 M 
A) 6)31 × 10-12 M 
B) 1)58 × 10-3 M 
C) 2)80 M 
D) 11.20 M

Question 19

Calculate the pH of a 1.60 M CH3NH3Cl solution.Kb for methylamine,CH3NH2,is 3.7 × 10-4.

Accepted Answer

A) 1)61 
B) 5)18 
C) 8)82 
D) 12.39 
A) 1)61 
B) 5)18 
C) 8)82 
D) 12.39

Question 20

-Of the elements indicated on the periodic table shown above,which forms the weakest binary acid,H2X or HX,where X = A,B,C,or D?

Accepted Answer

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

Exam 14: Aqueous Equilibria: Acids and Bases

The value of Ka for a 0.250 M HCN solution having a pH of 4.956 is ________.

Identify the set of Lewis acids.

Which one of the following is least able to behave as a Lewis base?

What is the strongest acid among the following?

The compound BF3 can be described as a(n)________.

What is the pH of a 0.020 M Ba(OH)2 solution?

A solution with a hydroxide ion concentration of 4.15 × 10- 6 M is ________ and has a hydrogen ion concentration of ________.

What is the pH of a 0.10 M H2Se solution that has the stepwise dissociation constants Ka1 = 1.3 × 10-4 and Ka2 = 1.0 × 10-11?

Acetic acid CH3COOH,has an acid dissociation constant of 1.8 × 10-5.What is the conjugate base of acetic acid and what is its base dissociation constant?

A 0.050 M solution of hydroxylamine,NH2OH,having Kb = 9.1 × 10-9 has a pH of ________.

The following pictures represent solutions of three salts MA;water molecules have been omitted for clarity.Dotted spheres represent Ay- ions;gray spheres represent Mx+ ions;black spheres represent oxygen atoms;and unshaded spheres represent hydrogen atoms. -Which picture represents an acidic salt?

How many grams of pyridine are there in 100 mL of an aqueous solution that has a pH of 9.00? The Kb for pyridine is 1.9 × 10-9 and the equation of interest is C5H5N(aq)+ H2O(l)⇌ C5H5NH+(aq)+ OH-(aq).

Which of the following salts are acidic?

Which one of the following is not considered to be a Lewis base?

Phenobarbital is an antiepileptic drug with a water solubility of 4.3 × 10-3 M and pKa = 7.4.What is the pH and percent ionization of 4.3 × 10-3 M phenobarbital?

Calculate the pH of a 0.020 M carbonic acid solution,H2CO3(aq),that has the stepwise dissociation constants Ka1 = 4.3 × 10-7 and Ka2 = 5.6 × 10-11.

Write a balanced equation for the dissociation of the Br∅nsted-Lowry acid HSO4- in water.

What is the hydroxide ion concentration of a lye solution that has a pH of 11.20?

Calculate the pH of a 1.60 M CH3NH3Cl solution.Kb for methylamine,CH3NH2,is 3.7 × 10-4.

-Of the elements indicated on the periodic table shown above,which forms the weakest binary acid,H2X or HX,where X = A,B,C,or D?

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Formulas, equations, and Moles

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids,solids,and Phase Changes

Solutions and Their Properties

Chemical Kinetics

Chemical Equilibrium

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

Nuclear Chemistry

Organic and Biological Chemistry

Filters

The value of K_a for a 0.250 M HCN solution having a pH of 4.956 is ________.

The compound BF₃ can be described as a(n)________.

What is the pH of a 0.020 M Ba(OH)₂ solution?

A solution with a hydroxide ion concentration of 4.15 × 10^{- 6} M is and has a hydrogen ion concentration of .

What is the pH of a 0.10 M H₂Se solution that has the stepwise dissociation constants K_a1 = 1.3 × 10^-4 and K_a2 = 1.0 × 10^-11?

Acetic acid CH₃COOH,has an acid dissociation constant of 1.8 × 10^-5.What is the conjugate base of acetic acid and what is its base dissociation constant?

A 0.050 M solution of hydroxylamine,NH₂OH,having K_b = 9.1 × 10^-9 has a pH of ________.

How many grams of pyridine are there in 100 mL of an aqueous solution that has a pH of 9.00? The K_b for pyridine is 1.9 × 10^-9 and the equation of interest is C₅H₅N(aq)+ H₂O(l)⇌ C₅H₅NH⁺(aq)+ OH^-(aq).

Phenobarbital is an antiepileptic drug with a water solubility of 4.3 × 10^-3 M and pK_a = 7.4.What is the pH and percent ionization of 4.3 × 10^-3 M phenobarbital?

Calculate the pH of a 0.020 M carbonic acid solution,H₂CO₃(aq),that has the stepwise dissociation constants K_a1 = 4.3 × 10^-7 and K_a2 = 5.6 × 10^-11.

Write a balanced equation for the dissociation of the Br∅nsted-Lowry acid HSO₄^- in water.

Calculate the pH of a 1.60 M CH₃NH₃Cl solution.K_b for methylamine,CH₃NH₂,is 3.7 × 10^-4.

-Of the elements indicated on the periodic table shown above,which forms the weakest binary acid,H₂X or HX,where X = A,B,C,or D?