Question 1

A dilute solution of HBr is found to have a pH of 3.55. What is [H3O+]?

Accepted Answer

A)  0.35 M 
B)  3.8×10 - 4 M 
C)  2.8×10 - 4 M 
D)  5.5×10 - 3 M 
E)  3.2×10 - 11 M 
A)  0.35 M 
B)  3.8×10 - 4 M 
C)  2.8×10 - 4 M 
D)  5.5×10 - 3 M 
E)  3.2×10 - 11 M

Question 2

A 0.250 M aqueous solution of a monoprotic weak acid has [H3O+] of 3.2×10 - 3. What is the analytical concentration of this weak acid?

Accepted Answer

A)  0.250 M 
B)  3.2×10 - 3 M 
C)  12.4×10 - 3 M 
D)  2.49 
E)  Depends on K a 
A)  0.250 M 
B)  3.2×10 - 3 M 
C)  12.4×10 - 3 M 
D)  2.49 
E)  Depends on K a

Question 3

In the unusual acid-base reaction HClO₄ + H₂ SO₄   ClO₄- + H ₃SO₄+ , one of the conjugate acid-base pairs is:

Accepted Answer

A)  HClO4, H2SO4 
B)  H2SO4, ClO4 -  
C)  ClO4 - , H3SO4+ 
D)  H3SO4+, H2SO4 
E)  HClO4, H3SO4+ 
A)  HClO4, H2SO4 
B)  H2SO4, ClO4 -  
C)  ClO4 - , H3SO4+ 
D)  H3SO4+, H2SO4 
E)  HClO4, H3SO4+

Question 4

Which of the following aqueous solutions is(are) considered basic ?
I. [H3O+] = 5.4×10 - 8 M
II. pOH = 9.0
III. [OH - ] = 4.3×10 - 4

Accepted Answer

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

Question 5

Consider the salt ammonium fluoride, NH4F, that is derived from a combination of a weak acid and a weak base as shown below. NH3 (g) + HF (g)→NH4F K b(NH3) = 1.8×10 - 5 and K a(HF) = 6.8×10 - 4 Which statement listed below is true?

Accepted Answer

A)  This salt is neutral when dissolved in water. 
B)  This salt is acidic when dissolved in water. 
C)  This salt is basic when dissolved in water. 
D)  This salt can be either acidic or neutral depending upon its concentration in water. 
E)  This salt can be either basic or neutral depending upon its concentration in water. 
A)  This salt is neutral when dissolved in water. 
B)  This salt is acidic when dissolved in water. 
C)  This salt is basic when dissolved in water. 
D)  This salt can be either acidic or neutral depending upon its concentration in water. 
E)  This salt can be either basic or neutral depending upon its concentration in water.

Question 6

Identify the Lewis base in the following reaction. H2O + H - →H2 + OH -

Accepted Answer

A)  H2O 
B)  H -  
C)  H2 
D)  OH -  
E)  None of these 
A)  H2O 
B)  H -  
C)  H2 
D)  OH -  
E)  None of these

Question 7

What is the H3O+ concentration in a solution formed by dissolving 63 g of HNO3 in 2.0 liters of water?
[molar mass of HNO3 = 63 g/mol]

Accepted Answer

A)  1.0 M 
B)  0.50 M 
C)  0.050 M 
D)  2.0 M 
E)  none of these 
A)  1.0 M 
B)  0.50 M 
C)  0.050 M 
D)  2.0 M 
E)  none of these

Question 8

Exhibit 15-6 Consider an aqueous 0.25 M solution of NaCN to answer the following question(s).
-Refer to Exhibit 15-6. What is the base ionization constant, K b, for CN - ?
K a(HCN) = 4.9×10 - 10

Accepted Answer

A)  4.9×10 - 24 
B)  1.2×10 - 10 
C)  2.0×10 - 9 
D)  2.0×10 - 5 
E)  4.9×104 
A)  4.9×10 - 24 
B)  1.2×10 - 10 
C)  2.0×10 - 9 
D)  2.0×10 - 5 
E)  4.9×104

Question 9

What is the pH of 0.025 M Ba(OH)2?

Accepted Answer

A)  0.050 
B)  1.30 
C)  12.70 
D)  2×10 - 13 
E)  none of these 
A)  0.050 
B)  1.30 
C)  12.70 
D)  2×10 - 13 
E)  none of these

Question 10

Which statement below is true about an aqueous solution of potassium fluoride, KF, and why?

Accepted Answer

A)  An aqueous solution of KF has a pH value that is greater than 7.0 because fluoride, F - , reacts with water to produce more OH - . 
B)  An aqueous solution of KF has a pH value that is greater than 7.0 because fluoride, F - , reacts with water to produce more H3O+. 
C)  An aqueous solution of KF has a pH value that is less than 7.0 because fluoride, F - , reacts with water to produce more OH - . 
D)  An aqueous solution of KF has a pH value that is less than 7.0 because fluoride, F - , reacts with water to produce more H3O+. 
E)  An aqueous solution of KF has a pH value that is equal to 7.0 because neither the potassium ion or the fluoride ion reacts with water to produce H3O+ or OH - . 
A)  An aqueous solution of KF has a pH value that is greater than 7.0 because fluoride, F - , reacts with water to produce more OH - . 
B)  An aqueous solution of KF has a pH value that is greater than 7.0 because fluoride, F - , reacts with water to produce more H3O+. 
C)  An aqueous solution of KF has a pH value that is less than 7.0 because fluoride, F - , reacts with water to produce more OH - . 
D)  An aqueous solution of KF has a pH value that is less than 7.0 because fluoride, F - , reacts with water to produce more H3O+. 
E)  An aqueous solution of KF has a pH value that is equal to 7.0 because neither the potassium ion or the fluoride ion reacts with water to produce H3O+ or OH - .

Question 11

A solution is found to have a pH of 10.45. What is [H3O+]?

Accepted Answer

A)  2.9×10 - 5 M 
B)  1.0 M 
C)  2.8×10 - 10 M 
D)  3.5×10 - 11 M 
E)  cannot be calculated from the information given 
A)  2.9×10 - 5 M 
B)  1.0 M 
C)  2.8×10 - 10 M 
D)  3.5×10 - 11 M 
E)  cannot be calculated from the information given

Question 12

What is the hydronium ion concentration, [H3O+], of an aqueous 0.083 M hydroxylamine, HONH2, solution?
Hydroxylamine is a basic substance when dissolved in water. K b(HONH2) = 1.1×10 - 8

Accepted Answer

A)  [H3O+] = 1.2×10 - 13 M 
B)  [H3O+] = 3.6×10 - 11 M 
C)  [H3O+] = 3.3×10 - 10 M 
D)  [H3O+] = 3.0×10 - 5 M 
E)  [H3O+] = 2.8×10 - 4 M 
A)  [H3O+] = 1.2×10 - 13 M 
B)  [H3O+] = 3.6×10 - 11 M 
C)  [H3O+] = 3.3×10 - 10 M 
D)  [H3O+] = 3.0×10 - 5 M 
E)  [H3O+] = 2.8×10 - 4 M

Question 13

Calculate the analytical concentration of a solution of acetic acid that has a pH of 3.00 ( K a for acetic acid is 1.8×10 - 5).

Accepted Answer

A)  1.0×10 - 3 
B)  1.0×10 - 6 
C)  0.056 
D)  0.010 
E)  2.0 
A)  1.0×10 - 3 
B)  1.0×10 - 6 
C)  0.056 
D)  0.010 
E)  2.0

Question 14

Employing a neutralization reaction , what reactants are required to prepare the salt, KNO3 reactants?
→KNO3

Accepted Answer

A)  KCl and HNO3 
B)  K2SO4 and HNO3 
C)  KOH and NaNO3 
D)  KOH and HNO3 
E)  KOH and HCl 
A)  KCl and HNO3 
B)  K2SO4 and HNO3 
C)  KOH and NaNO3 
D)  KOH and HNO3 
E)  KOH and HCl

Question 15

When comparing acid strengths, which one of the items listed below is not correctly labeled?

Accepted Answer

A)  H2S 2O 
B)  H2SeO4 2SO4 
C)  SiH4 3 
D)  HNO2 3 
E)  H2PO4 -  > HPO4 - 2 
A)  H2S 2O 
B)  H2SeO4 2SO4 
C)  SiH4 3 
D)  HNO2 3 
E)  H2PO4 -  > HPO4 - 2

Question 16

The pH of a certain black coffee is 5.3. What is its hydroxide ion concentration, [OH - ]?

Accepted Answer

A)  2.0×10 - 9 M 
B)  5.0×10 - 6 M 
C)  8.7 M 
D)  2.0×105 M 
E)  5.0×108 M 
A)  2.0×10 - 9 M 
B)  5.0×10 - 6 M 
C)  8.7 M 
D)  2.0×105 M 
E)  5.0×108 M

Question 17

Which of the following aqueous solutions is(are) considered basic ?
I. [H3O+] = 3.4×10 - 10 M
II. pH = 8.54
III. [OH - ] = 6.7×10 - 4 M

Accepted Answer

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

Question 18

A Bronsted-Lowry acid is

Accepted Answer

A)  a proton acceptor. 
B)  an electron acceptor. 
C)  an electron donor. 
D)  a binary hydride. 
E)  a proton donor 
A)  a proton acceptor. 
B)  an electron acceptor. 
C)  an electron donor. 
D)  a binary hydride. 
E)  a proton donor

Question 19

If we compare the acid/base properties of a 0.5 M solution of A -  to a 0.5 M solution of HA, K a = 1.0×10 - 4:

Accepted Answer

A)  The A -  solution is more acidic. 
B)  the pH of the A -  solution is less. 
C)  the A -  solution will be basic. 
D)  A -  is the conjugate acid, and we need to know if K a of A -  is greater or less than K a for HA. 
E)  none of these. 
A)  The A -  solution is more acidic. 
B)  the pH of the A -  solution is less. 
C)  the A -  solution will be basic. 
D)  A -  is the conjugate acid, and we need to know if K a of A -  is greater or less than K a for HA. 
E)  none of these.

Exam 15: Solutions of Acids and Bases

A dilute solution of HBr is found to have a pH of 3.55. What is [H3O+]?

A 0.250 M aqueous solution of a monoprotic weak acid has [H3O+] of 3.2×10 - 3. What is the analytical concentration of this weak acid?

In the unusual acid-base reaction HClO₄ + H₂ SO₄ ClO₄- + H ₃SO₄+ , one of the conjugate acid-base pairs is:

Which of the following aqueous solutions is(are) considered basic ? I. [H3O+] = 5.4×10 - 8 M II. pOH = 9.0 III. [OH - ] = 4.3×10 - 4

Consider the salt ammonium fluoride, NH4F, that is derived from a combination of a weak acid and a weak base as shown below. NH3 (g) + HF (g)→NH4F K b(NH3) = 1.8×10 - 5 and K a(HF) = 6.8×10 - 4 Which statement listed below is true?

Identify the Lewis base in the following reaction. H2O + H - →H2 + OH -

What is the H3O+ concentration in a solution formed by dissolving 63 g of HNO3 in 2.0 liters of water? [molar mass of HNO3 = 63 g/mol]

Exhibit 15-6 Consider an aqueous 0.25 M solution of NaCN to answer the following question(s). -Refer to Exhibit 15-6. What is the base ionization constant, K b, for CN - ? K a(HCN) = 4.9×10 - 10

What is the pH of 0.025 M Ba(OH)2?

Which statement below is true about an aqueous solution of potassium fluoride, KF, and why?

A solution is found to have a pH of 10.45. What is [H3O+]?

What is the hydronium ion concentration, [H3O+], of an aqueous 0.083 M hydroxylamine, HONH2, solution? Hydroxylamine is a basic substance when dissolved in water. K b(HONH2) = 1.1×10 - 8

Calculate the analytical concentration of a solution of acetic acid that has a pH of 3.00 ( K a for acetic acid is 1.8×10 - 5).

Employing a neutralization reaction , what reactants are required to prepare the salt, KNO3 reactants? →KNO3

When comparing acid strengths, which one of the items listed below is not correctly labeled?

The pH of a certain black coffee is 5.3. What is its hydroxide ion concentration, [OH - ]?

Which of the following aqueous solutions is(are) considered basic ? I. [H3O+] = 3.4×10 - 10 M II. pH = 8.54 III. [OH - ] = 6.7×10 - 4 M

A Bronsted-Lowry acid is

If we compare the acid/base properties of a 0.5 M solution of A - to a 0.5 M solution of HA, K a = 1.0×10 - 4:

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A dilute solution of HBr is found to have a pH of 3.55. What is [H₃O⁺]?

A 0.250 M aqueous solution of a monoprotic weak acid has [H₃O⁺] of 3.2×10^{- 3}. What is the analytical concentration of this weak acid?

Which of the following aqueous solutions is(are) considered basic ? I. [H₃O⁺] = 5.4×10^{- 8} M II. pOH = 9.0 III. [OH^-] = 4.3×10^{- 4}

Consider the salt ammonium fluoride, NH₄F, that is derived from a combination of a weak acid and a weak base as shown below. NH₃ (g) + HF (g)→NH₄F K _b(NH₃) = 1.8×10^{- 5} and K _a(HF) = 6.8×10^{- 4} Which statement listed below is true?

Identify the Lewis base in the following reaction. H₂O + H^-→H₂ + OH^-

What is the H₃O⁺ concentration in a solution formed by dissolving 63 g of HNO₃ in 2.0 liters of water? [molar mass of HNO₃ = 63 g/mol]

Exhibit 15-6 Consider an aqueous 0.25 M solution of NaCN to answer the following question(s). -Refer to Exhibit 15-6. What is the base ionization constant, K _b, for CN^-? K _a(HCN) = 4.9×10^{- 10}

What is the pH of 0.025 M Ba(OH)₂?

A solution is found to have a pH of 10.45. What is [H₃O⁺]?

What is the hydronium ion concentration, [H₃O⁺], of an aqueous 0.083 M hydroxylamine, HONH₂, solution? Hydroxylamine is a basic substance when dissolved in water. K _b(HONH₂) = 1.1×10^{- 8}

Calculate the analytical concentration of a solution of acetic acid that has a pH of 3.00 ( K _a for acetic acid is 1.8×10^{- 5}).

Employing a neutralization reaction , what reactants are required to prepare the salt, KNO₃ reactants? →KNO₃

The pH of a certain black coffee is 5.3. What is its hydroxide ion concentration, [OH^-]?

Which of the following aqueous solutions is(are) considered basic ? I. [H₃O⁺] = 3.4×10^{- 10} M II. pH = 8.54 III. [OH^-] = 6.7×10^{- 4} M

If we compare the acid/base properties of a 0.5 M solution of A^- to a 0.5 M solution of HA, K _a = 1.0×10^{- 4}: