Question 1

Regarding acid strength, which of the following is not correctly assigned?

Accepted Answer

A)  (stronger acid) H2CO3 > HCO31 -  (weaker acid) 
B)  (stronger acid) H2Se > H2Te (weaker acid) 
C)  (stronger acid) H2O > NH3 (weaker acid) 
D)  (stronger acid) H2SO4 > H3PO4 (weaker acid) 
E)  (stronger acid) HClO2 > HClO (weaker acid) 
A)  (stronger acid) H2CO3 > HCO31 -  (weaker acid) 
B)  (stronger acid) H2Se > H2Te (weaker acid) 
C)  (stronger acid) H2O > NH3 (weaker acid) 
D)  (stronger acid) H2SO4 > H3PO4 (weaker acid) 
E)  (stronger acid) HClO2 > HClO (weaker acid)

Question 2

The hydroxide ion concentration in a solution with pH = 3.50 is:

Accepted Answer

A)  3.2×10 - 2 M 
B)  3.2×10 - 4 M 
C)  3.2×10 - 11 M 
D)  3.2×10 - 10 M 
E)  none of these 
A)  3.2×10 - 2 M 
B)  3.2×10 - 4 M 
C)  3.2×10 - 11 M 
D)  3.2×10 - 10 M 
E)  none of these

Question 3

What is the pH of a 2.6 M aqueous solution of Ba(OH)2?

Accepted Answer

A)  7.94×10 - 6 
B)  0.71 
C)  13.29 
D)  14.41 
E)  14.72 
A)  7.94×10 - 6 
B)  0.71 
C)  13.29 
D)  14.41 
E)  14.72

Question 4

The following equilibrium is established in water solution:
HCOOH + H2O→HCOO -  + H3O+ K  a = 1.8×10 - 4 Which of the following is false?

Accepted Answer

A)  HCOO -  is the conjugate acid of HCOOH. 
B)  H2O is the conjugate base of H3O+. 
C)  HCOOH is a weak acid. 
D)  H2O is a weak base. 
E)  Hydroxide concentration is negligible with respect to hydrogen ion concentration. 
A)  HCOO -  is the conjugate acid of HCOOH. 
B)  H2O is the conjugate base of H3O+. 
C)  HCOOH is a weak acid. 
D)  H2O is a weak base. 
E)  Hydroxide concentration is negligible with respect to hydrogen ion concentration.

Question 5

What is the acid ionization constant , K a, for lactic acid, CH3CH(OH)COOH, if the base ionization constant, K b, of CH3CH(OH)COO -  equals 7.1×10 - 11?

Accepted Answer

A)  K a = 7.1×10 - 25 
B)  K a = 7.1×10 - 11 
C)  K a = 1.4×10 - 4 
D)  K a = 7.1×103 
E)  K a = 1.4×1024 
A)  K a = 7.1×10 - 25 
B)  K a = 7.1×10 - 11 
C)  K a = 1.4×10 - 4 
D)  K a = 7.1×103 
E)  K a = 1.4×1024

Question 6

Pyridine (p K b = 8.74) reacts with formic acid (p K a = 3.74) to form the pyridinium ion and the formate ion:
C6H5N + HCOOH→C5H5NH+ + HCOO -  Which of the following is true?

Accepted Answer

A)  Pyridinium ion is a stronger acid than formic acid. 
B)  Formate ion is a stronger base than pyridine. 
C)  A solution which is 0.1 M pyridine and 0.1 M pyridinium chloride is basic. 
D)  A solution which is 0.1 M formic acid and 0.1 M sodium formate is basic. 
E)  A solution of 0.1 M pyridine and 0.1 M sodium formate is basic. 
A)  Pyridinium ion is a stronger acid than formic acid. 
B)  Formate ion is a stronger base than pyridine. 
C)  A solution which is 0.1 M pyridine and 0.1 M pyridinium chloride is basic. 
D)  A solution which is 0.1 M formic acid and 0.1 M sodium formate is basic. 
E)  A solution of 0.1 M pyridine and 0.1 M sodium formate is basic.

Question 7

Exhibit 15-3 Ephedrine (CS1U1B110S1U1B0HS1U1B115S1U1B0ON), a central nervous system stimulant, is used in nasal sprays as a decongestant. This compound is a weak organic base :
CS1U1B110S1U1B0HS1U1B115S1U1B0ON (aq) + H₂ O   HCS1U1B110S1U1B0HS1U1B115S1U1B0ON + (aq) + OH - (aq) Consider a 0.035 M
Solution of ephedrine that has a pH of 11.33 to answer the following problem(s).
-Refer to Exhibit 15-3. What is the base ionization constant , K b , for the dissolution of ephedrine in water?

Accepted Answer

A)  6.3×10 - 22 
B)  7.5×10 - 11 
C)  1.3×10 - 4 
D)  2.1×10 - 3 
E)  6.4×10 - 2 
A)  6.3×10 - 22 
B)  7.5×10 - 11 
C)  1.3×10 - 4 
D)  2.1×10 - 3 
E)  6.4×10 - 2

Question 8

Employing a neutralization reaction , which reactants are used to prepare the salt Potassium Sulfate, K2SO4 reactants?
→K2SO4

Accepted Answer

A)  KCl and H2SO4 
B)  KNO3 and H2SO4 
C)  KOH and H2SO4 
D)  KOH and Na2SO4 
E)  KCl and Na2SO4 
A)  KCl and H2SO4 
B)  KNO3 and H2SO4 
C)  KOH and H2SO4 
D)  KOH and Na2SO4 
E)  KCl and Na2SO4

Question 9

A weak acid

Accepted Answer

A)  does not react with base 
B)  does not react with glass 
C)  does not burn skin 
D)  does not dissociate fully 
E)  does not pose a disposal problem 
A)  does not react with base 
B)  does not react with glass 
C)  does not burn skin 
D)  does not dissociate fully 
E)  does not pose a disposal problem

Question 10

Which of the following aqueous solutions is(are) considered acidic ?
I. pOH = 12.0
II. [H3O+] = 4.2×10 - 9
III. [OH - ] = 5.3×10 - 10

Accepted Answer

A)  II only 
B)  I and II 
C)  I and III 
D)  II and III 
E)  All of these 
A)  II only 
B)  I and II 
C)  I and III 
D)  II and III 
E)  All of these

Question 11

From the information given below which one of the 5 solutions would be the most acidic?

Accepted Answer

A)  pH = 6 
B)  pOH = 9 
C)  [H3O+] = 10 - 3 M 
D)  [OH - ] = 10 - 10 
E)  pOH = 12 
A)  pH = 6 
B)  pOH = 9 
C)  [H3O+] = 10 - 3 M 
D)  [OH - ] = 10 - 10 
E)  pOH = 12

Question 12

The definition of a Lewis base is:

Accepted Answer

A)  an electron pair donor. 
B)  a proton donor. 
C)  boron trifluoride. 
D)  an electron pair acceptor. 
E)  an electrophile. 
A)  an electron pair donor. 
B)  a proton donor. 
C)  boron trifluoride. 
D)  an electron pair acceptor. 
E)  an electrophile.

Question 13

The pH of a 0.0338 M solution of a weak acid is 2.85. What is K a of this acid?

Accepted Answer

A)  3.4×10 - 2 
B)  1.4×10 - 3 
C)  3.4×10 - 4 
D)  6.2×10 - 5 
E)  5.9×10 - 5 
A)  3.4×10 - 2 
B)  1.4×10 - 3 
C)  3.4×10 - 4 
D)  6.2×10 - 5 
E)  5.9×10 - 5

Question 14

Identify the Lewis acid in the following Lewis-Acid base reaction. Fe3+ + 6 H2O→[Fe(H2O)6]3+

Accepted Answer

A)  Fe3+ 
B)  H2O 
C)  [Fe(H2O)6]3+ 
D)  H3O+ 
E)  None of these 
A)  Fe3+ 
B)  H2O 
C)  [Fe(H2O)6]3+ 
D)  H3O+ 
E)  None of these

Question 15

Which of the following salts would be considered a basic salt when dissolved in water?

Accepted Answer

A)  KBr 
B)  NaCl 
C)  LiF 
D)  Na2SO4 
E)  CsI 
A)  KBr 
B)  NaCl 
C)  LiF 
D)  Na2SO4 
E)  CsI

Question 16

What is the pH of an aqueous 3.3 M Ba(OH)2 solution?

Accepted Answer

A)  pH = - 0.51 
B)  pH = - 0.81 
C)  pH = 13.19 
D)  pH = 13.49 
E)  pH = 14.82 
A)  pH = - 0.51 
B)  pH = - 0.81 
C)  pH = 13.19 
D)  pH = 13.49 
E)  pH = 14.82

Question 17

Consider the following unfinished table of weak acids with their corresponding
P K a values and K a values. Weak Acid p K a K a HNO2 3.35 -- HF -- 6.8×10 - 4 HCN 9.31 --
Arrange these three acids in order of increasing acid strength .

Accepted Answer

A)  (weakest) HNO2 2 2 (strongest) 
D)  (weakest) HCN 2 2 < HCN (strongest) 
A)  (weakest) HNO2 2 2 (strongest) 
D)  (weakest) HCN 2 2 < HCN (strongest)

Question 18

Which of these aqueous solutions would have a pH greater than 7?

Accepted Answer

A)  a solution of HCl 
B)  a solution of a weak acid 
C)  a solution of a strong acid 
D)  a solution of sodium acetate 
E)  a solution of ammonium chloride 
A)  a solution of HCl 
B)  a solution of a weak acid 
C)  a solution of a strong acid 
D)  a solution of sodium acetate 
E)  a solution of ammonium chloride

Question 19

Which salt(s) listed below form(s) an acidic aqueous solution when dissolved in water?
I. KNO2
II. NaF
III. NH4ClO4

Accepted Answer

A)  I only 
B)  II only 
C)  III only 
D)  I and II 
E)  All of these. 
A)  I only 
B)  II only 
C)  III only 
D)  I and II 
E)  All of these.

Question 20

A 0.050 M solution of ammonium chloride is prepared. Find the H3O+ concentration:
( K b for ammonia = 1.8×10 - 5)

Accepted Answer

A)  5.3×10 - 6 M 
B)  5.3×10 - 4 M 
C)  2.0×10 - 13 M 
D)  9.5×10 - 4 M 
E)  none of these 
A)  5.3×10 - 6 M 
B)  5.3×10 - 4 M 
C)  2.0×10 - 13 M 
D)  9.5×10 - 4 M 
E)  none of these

Exam 15: Solutions of Acids and Bases

Regarding acid strength, which of the following is not correctly assigned?

The hydroxide ion concentration in a solution with pH = 3.50 is:

What is the pH of a 2.6 M aqueous solution of Ba(OH)2?

The following equilibrium is established in water solution: HCOOH + H2O→HCOO - + H3O+ K a = 1.8×10 - 4 Which of the following is false?

What is the acid ionization constant , K a, for lactic acid, CH3CH(OH)COOH, if the base ionization constant, K b, of CH3CH(OH)COO - equals 7.1×10 - 11?

Pyridine (p K b = 8.74) reacts with formic acid (p K a = 3.74) to form the pyridinium ion and the formate ion: C6H5N + HCOOH→C5H5NH+ + HCOO - Which of the following is true?

Employing a neutralization reaction , which reactants are used to prepare the salt Potassium Sulfate, K2SO4 reactants? →K2SO4

A weak acid

Which of the following aqueous solutions is(are) considered acidic ? I. pOH = 12.0 II. [H3O+] = 4.2×10 - 9 III. [OH - ] = 5.3×10 - 10

From the information given below which one of the 5 solutions would be the most acidic?

The definition of a Lewis base is:

The pH of a 0.0338 M solution of a weak acid is 2.85. What is K a of this acid?

Identify the Lewis acid in the following Lewis-Acid base reaction. Fe3+ + 6 H2O→[Fe(H2O)6]3+

Which of the following salts would be considered a basic salt when dissolved in water?

What is the pH of an aqueous 3.3 M Ba(OH)2 solution?

Consider the following unfinished table of weak acids with their corresponding P K a values and K a values. Weak Acid p K a K a HNO2 3.35 -- HF -- 6.8×10 - 4 HCN 9.31 -- Arrange these three acids in order of increasing acid strength .

Which of these aqueous solutions would have a pH greater than 7?

Which salt(s) listed below form(s) an acidic aqueous solution when dissolved in water? I. KNO2 II. NaF III. NH4ClO4

A 0.050 M solution of ammonium chloride is prepared. Find the H3O+ concentration: ( K b for ammonia = 1.8×10 - 5)

Introduction to Chemistry

Atoms, Molecules, and Ions

Equations, the Mole, and Chemical Formulas

Chemical Reactions in Solution

Thermochemistry

The Gaseous State

Electronic Structure

The Periodic Table: Structure and Trends

Chemical Bonds

Molecular Structure and Bonding Theories

Liquids and Solids

Solutions

Chemical Kinetics

Chemical Equilibrium

Reactions Between Acids and Bases

Chemical Thermodynamics

Electrochemistry

Transition Metals, Coordination Chemistry and Metallurgy

The Chemistry of Hydrogen, Elements in Groups 3A Through 6A, and the Noble Gases

Nuclear Chemistry

Organic Chemistry and Biochemistry

Filters

What is the pH of a 2.6 M aqueous solution of Ba(OH)₂?

The following equilibrium is established in water solution: HCOOH + H₂O→HCOO^- + H₃O⁺ K _a = 1.8×10^{- 4} Which of the following is false?

What is the acid ionization constant , K _a, for lactic acid, CH₃CH(OH)COOH, if the base ionization constant, K _b, of CH₃CH(OH)COO^- equals 7.1×10^{- 11}?

Pyridine (p K _b = 8.74) reacts with formic acid (p K _a = 3.74) to form the pyridinium ion and the formate ion: C₆H₅N + HCOOH→C₅H₅NH⁺ + HCOO^- Which of the following is true?

Employing a neutralization reaction , which reactants are used to prepare the salt Potassium Sulfate, K₂SO₄ reactants? →K₂SO₄

Which of the following aqueous solutions is(are) considered acidic ? I. pOH = 12.0 II. [H₃O⁺] = 4.2×10^{- 9} III. [OH^-] = 5.3×10^{- 10}

The pH of a 0.0338 M solution of a weak acid is 2.85. What is K _aof this acid?

Identify the Lewis acid in the following Lewis-Acid base reaction. Fe³⁺ + 6 H₂O→[Fe(H₂O)₆]³⁺

What is the pH of an aqueous 3.3 M Ba(OH)₂ solution?

Consider the following unfinished table of weak acids with their corresponding P K _a values and K _a values. Weak Acid p K _a K _a HNO₂ 3.35 -- HF -- 6.8×10^{- 4} HCN 9.31 -- Arrange these three acids in order of increasing acid strength .

Which salt(s) listed below form(s) an acidic aqueous solution when dissolved in water? I. KNO₂ II. NaF III. NH₄ClO₄

A 0.050 M solution of ammonium chloride is prepared. Find the H₃O⁺ concentration: ( K _b for ammonia = 1.8×10^{- 5})