Question 1

The pH of a solution is 2.62 at 25 °C. Calculate the pOH of this solution at 25 °C.

Accepted Answer

A)  2.40 
B)  8.33 
C)  4.88 
D)  11.4 
E)  12.7 
A)  2.40 
B)  8.33 
C)  4.88 
D)  11.4 
E)  12.7 D

Question 2

Which of the following is a polyprotic acid?

Accepted Answer

A)  HF 
B)  H2SO4 
C)  HCN 
D)  HNO3 
E)  HC2H3O2 
A)  HF 
B)  H2SO4 
C)  HCN 
D)  HNO3 
E)  HC2H3O2 B

Question 3

Calculate the pH of a 0.345 mol L-1 solution of formic acid, Ka = 1.8 × 10-4.

Accepted Answer

A)  2.10 
B)  2.49 
C)  3.17 
D)  1.60 
E)  2.04 
A)  2.10 
B)  2.49 
C)  3.17 
D)  1.60 
E)  2.04 A

Question 4

Calculate the pH of a 0.400 mol L-1 solution of formic acid, Ka = 1.8 × 10-4.

Accepted Answer

A)  3.71 
B)  3.44 
C)  2.29 
D)  4.00 
E)  2.07 
A)  3.71 
B)  3.44 
C)  2.29 
D)  4.00 
E)  2.07

Question 5

Which Bronsted-Lowry acid is not considered to be a strong acid in water?

Accepted Answer

A)  H Br 
B)  H Cl  
C)  H N O2 
D)  H ClO4 
A)  H Br 
B)  H Cl  
C)  H N O2 
D)  H ClO4

Question 6

Find the percent ionization of a 0.337 mol L-1 HF solution. The Ka for HF is 3.5 × 10-4.

Accepted Answer

A)  1.1% 
B)  1.2 × 10-2% 
C)  3.2% 
D)  3.5 × 10-2% 
E)  4.7% 
A)  1.1% 
B)  1.2 × 10-2% 
C)  3.2% 
D)  3.5 × 10-2% 
E)  4.7%

Question 7

Determine the pOH of a 0.188 mol L-1 NH3 solution at 25 °C. The Kb of NH3 is 1.76 × 10-5.

Accepted Answer

A)  5.480 
B)  2.740 
C)  8.520 
D)  11.260 
E)  12.656 
A)  5.480 
B)  2.740 
C)  8.520 
D)  11.260 
E)  12.656

Question 8

When dissolved in water, which compound is generally considered to be an Arrhenius acid?

Accepted Answer

A)  H CN  
B)  NaOH 
C)  Na F  
D)  CH3CH2OH 
A)  H CN  
B)  NaOH 
C)  Na F  
D)  CH3CH2OH

Question 9

Determine the pH in a 0.235 mol L-1 NaOH solution.

Accepted Answer

A)  13.76 
B)  0.24 
C)  13.37 
D)  0.63 
E)  12 
A)  13.76 
B)  0.24 
C)  13.37 
D)  0.63 
E)  12

Question 10

Which of the following groups is found in carboxylic acids (like acetic acid)?

Accepted Answer

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

Question 11

Calculate the pH of a 1.60 mol L-1 CH3NH3Cl solution. Kb for methylamine, CH3NH2, is  3.7x10-4

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 12

What is the conjugate base of H2PO4⁻ ?

Accepted Answer

A)  HPO42- 
B)  PO43- 
C)  H3PO4 
D)  H3O+ 
E)  OH⁻ 
A)  HPO42- 
B)  PO43- 
C)  H3PO4 
D)  H3O+ 
E)  OH⁻

Question 13

What is the hydronium ion concentration of a 0. 150 mol L-1 hypochlorous acid solution with  Ka=3.5 x 10-8 ? The equation for the dissociation of hypochlorous acid is below: HOCl(aq)+H2O(l) ⇌ H3O+(aq)+OCl-(aq)

Accepted Answer

A)  1.9 × 10-4 mol L-1 
B)  7.2 × 10-4 mol L-1 
C)  2.8 × 10-5 mol L-1 
D)  7.2 × 10-5 mol L-1 
A)  1.9 × 10-4 mol L-1 
B)  7.2 × 10-4 mol L-1 
C)  2.8 × 10-5 mol L-1 
D)  7.2 × 10-5 mol L-1

Question 14

A 4.0 × 10-3 mol L-1 aqueous solution of Ca(OH)2  at 25.0 °C has a pH of ________.

Accepted Answer

A)  2.40 
B)  11.60 
C)  8.0 × 10-3 
D)  2.10 
E)  11.90 
A)  2.40 
B)  11.60 
C)  8.0 × 10-3 
D)  2.10 
E)  11.90

Question 15

Identify acid, base, conjugate acid, and conjugate base in the following reaction: 
H2CO3(aq) + H2O(l) ⇌ HCO3-(aq) + H3O+(aq)

Accepted Answer

A)  H2CO3 is an acid, H2O is a base, HCO3- is a conjugate base, and H3O+ is a conjugate acid. 
B)  H2CO3 is a conjugate acid, H2O is a conjugate base, HCO3- is a base, and H3O+ is an acid. 
C)  H2CO3 is an acid, H2O is a conjugate base, HCO3- is a base, and H3O+ is a conjugate acid. 
D)  H2CO3 is a conjugate acid, H2O is a base, HCO3- is a conjugate base, and H3O+ is an acid. 
E)  H2CO3 is an acid, H2O is a conjugate acid, HCO3- is a base, and H3O+ is a conjugate base. 
A)  H2CO3 is an acid, H2O is a base, HCO3- is a conjugate base, and H3O+ is a conjugate acid. 
B)  H2CO3 is a conjugate acid, H2O is a conjugate base, HCO3- is a base, and H3O+ is an acid. 
C)  H2CO3 is an acid, H2O is a conjugate base, HCO3- is a base, and H3O+ is a conjugate acid. 
D)  H2CO3 is a conjugate acid, H2O is a base, HCO3- is a conjugate base, and H3O+ is an acid. 
E)  H2CO3 is an acid, H2O is a conjugate acid, HCO3- is a base, and H3O+ is a conjugate base.

Question 16

What is the Kw of pure water at 50.0 °C, if the pH is 6.630?

Accepted Answer

A)  2.34 × 10-7 
B)  5.50 × 10-14 
C)  2.13 × 10-14 
D)  1.00 × 10-14 
E)  2.34 × 10-14 
A)  2.34 × 10-7 
B)  5.50 × 10-14 
C)  2.13 × 10-14 
D)  1.00 × 10-14 
E)  2.34 × 10-14

Question 17

Calculate the hydroxide ion concentration in an aqueous solution that contains 3.50 × 10-4 mol L-1 in hydronium ion.

Accepted Answer

A)  2.86 × 10-3 mol L-1 
B)  2.86 × 10-10 mol L-1 
C)  2.86 × 10-11 mol L-1 
D)  3.50 × 10-11 mol L-1 
A)  2.86 × 10-3 mol L-1 
B)  2.86 × 10-10 mol L-1 
C)  2.86 × 10-11 mol L-1 
D)  3.50 × 10-11 mol L-1

Question 18

What is the pH of pure water at 40.0 °C if the Kw at this temperature is 2.92 × 10-14?

Accepted Answer

A)  6.767 
B)  0.465 
C)  7.000 
D)  7.233 
E)  8.446 
A)  6.767 
B)  0.465 
C)  7.000 
D)  7.233 
E)  8.446

Question 19

Calculate the concentration of OH⁻ in a solution that contains 3.9 × 10-4 mol L-1 H3O⁺ at 25 °C. Also identify the solution as acidic, basic, or neutral.

Accepted Answer

A)  2.6 × 10-11 mol L-1, acidic 
B)  2.6 × 10-11 mol L-1, basic 
C)  3.9 × 10-4 mol L-1, neutral 
D)  2.7 × 10-2 mol L-1, basic 
E)  2.7 × 10-2 mol L-1, acidic 
A)  2.6 × 10-11 mol L-1, acidic 
B)  2.6 × 10-11 mol L-1, basic 
C)  3.9 × 10-4 mol L-1, neutral 
D)  2.7 × 10-2 mol L-1, basic 
E)  2.7 × 10-2 mol L-1, acidic

Question 20

Which of the following is correct?

Accepted Answer

A)  According to the Bronsted-Lowry theory, an acid is a proton donor while a base is a proton acceptor. 
B)  According to the Bronsted-Lowry theory, an acid is a proton acceptor while a base is a proton donor. 
C)  According to the Bronsted-Lowry theory, an acid is a proton donor while a base is a hydroxide ion acceptor. 
D)  According to the Bronsted-Lowry theory, an acid is a hydroxide donor while a base is a proton acceptor. 
E)  According to the Bronsted-Lowry theory, an acid is a hydroxide donor while a base is a hydroxide acceptor. 
A)  According to the Bronsted-Lowry theory, an acid is a proton donor while a base is a proton acceptor. 
B)  According to the Bronsted-Lowry theory, an acid is a proton acceptor while a base is a proton donor. 
C)  According to the Bronsted-Lowry theory, an acid is a proton donor while a base is a hydroxide ion acceptor. 
D)  According to the Bronsted-Lowry theory, an acid is a hydroxide donor while a base is a proton acceptor. 
E)  According to the Bronsted-Lowry theory, an acid is a hydroxide donor while a base is a hydroxide acceptor.

Exam 15: Acids and Bases

The pH of a solution is 2.62 at 25 °C. Calculate the pOH of this solution at 25 °C.

Which of the following is a polyprotic acid?

Calculate the pH of a 0.345 mol L-1 solution of formic acid, Ka = 1.8 × 10-4.

Calculate the pH of a 0.400 mol L-1 solution of formic acid, Ka = 1.8 × 10-4.

Which Bronsted-Lowry acid is not considered to be a strong acid in water?

Find the percent ionization of a 0.337 mol L-1 HF solution. The Ka for HF is 3.5 × 10-4.

Determine the pOH of a 0.188 mol L-1 NH3 solution at 25 °C. The Kb of NH3 is 1.76 × 10-5.

When dissolved in water, which compound is generally considered to be an Arrhenius acid?

Determine the pH in a 0.235 mol L-1 NaOH solution.

Which of the following groups is found in carboxylic acids (like acetic acid)?

Calculate the pH of a 1.60 mol L-1 CH3NH3Cl solution. Kb for methylamine, CH3NH2, is 3.7x10-4

What is the conjugate base of H2PO4⁻ ?

What is the hydronium ion concentration of a 0. 150 mol L-1 hypochlorous acid solution with Ka=3.5 x 10-8 ? The equation for the dissociation of hypochlorous acid is below: HOCl(aq)+H2O(l) ⇌ H3O+(aq)+OCl-(aq)

A 4.0 × 10-3 mol L-1 aqueous solution of Ca(OH)2 at 25.0 °C has a pH of ________.

Identify acid, base, conjugate acid, and conjugate base in the following reaction: H2CO3(aq) + H2O(l) ⇌ HCO3-(aq) + H3O+(aq)

What is the Kw of pure water at 50.0 °C, if the pH is 6.630?

Calculate the hydroxide ion concentration in an aqueous solution that contains 3.50 × 10-4 mol L-1 in hydronium ion.

What is the pH of pure water at 40.0 °C if the Kw at this temperature is 2.92 × 10-14?

Calculate the concentration of OH⁻ in a solution that contains 3.9 × 10-4 mol L-1 H3O⁺ at 25 °C. Also identify the solution as acidic, basic, or neutral.

Which of the following is correct?

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Filters

Calculate the pH of a 0.345 mol L^-1 solution of formic acid, K_a = 1.8 × 10^-4.

Calculate the pH of a 0.400 mol L^-1 solution of formic acid, K_a = 1.8 × 10^-4.

Find the percent ionization of a 0.337 mol L^-1 HF solution. The K_a for HF is 3.5 × 10^-4.

Determine the pOH of a 0.188 mol L^-1 NH₃ solution at 25 °C. The K_bof NH₃ is 1.76 × 10^-5.

Determine the pH in a 0.235 mol L^-1 NaOH solution.

Calculate the pH of a 1.60 mol L^-1 CH₃NH₃Cl solution. K_b for methylamine, CH₃NH₂, is 3.7x10^-4

What is the conjugate base of H₂PO₄⁻ ?

What is the hydronium ion concentration of a 0. 150 mol L^-1 hypochlorous acid solution with Ka=3.5 x 10-8 ? The equation for the dissociation of hypochlorous acid is below: HOCl_(aq)+H₂O(l) ⇌ H₃O+(aq)+OCl-_(aq)

A 4.0 × 10^-3 mol L^-1 aqueous solution of Ca(OH)₂ at 25.0 °C has a pH of ________.

Identify acid, base, conjugate acid, and conjugate base in the following reaction: H₂CO₃(aq) + H₂O(l) ⇌ HCO₃^-(aq) + H₃O⁺(aq)

What is the K_w of pure water at 50.0 °C, if the pH is 6.630?

Calculate the hydroxide ion concentration in an aqueous solution that contains 3.50 × 10^-⁴ mol L^-1 in hydronium ion.

What is the pH of pure water at 40.0 °C if the K_w at this temperature is 2.92 × 10^-14?

Calculate the concentration of OH⁻ in a solution that contains 3.9 × 10^-4 mol L^-1 H₃O⁺ at 25 °C. Also identify the solution as acidic, basic, or neutral.