Question 1

A 0.210-g sample of an acid (molar mass = 192 g/mol) is titrated with 30.5 mL of 0.108 M NaOH to a phenolphthalein endpoint. The formula of the acid is

Accepted Answer

A)  H3A. 
B)  H2A. 
C)  H4A. 
D)  HA. 
E)  not enough information given 
A)  H3A. 
B)  H2A. 
C)  H4A. 
D)  HA. 
E)  not enough information given A

Question 2

Calculate the pH at the equivalence point for the titration of 1.0 M ethylamine, C2H5NH2, by 1.0 M perchloric acid, HClO4. (pKb for C2H5NH2 = 3.25)

Accepted Answer

A)  6.05 
B)  2.24 
C)  2.09 
D)  5.38 
E)  5.53 
A)  6.05 
B)  2.24 
C)  2.09 
D)  5.38 
E)  5.53 E

Question 3

The solubility of M(OH)2 in 0.010 M KOH is 1.0 × 10-5 mol/L. What is Ksp for M(OH)2?

Accepted Answer

A)  1.0 × 10-10 
B)  4.0 × 10-15 
C)  1.0 × 10-2 
D)  1.0 × 10-12 
E)  1.0 × 10-9 
A)  1.0 × 10-10 
B)  4.0 × 10-15 
C)  1.0 × 10-2 
D)  1.0 × 10-12 
E)  1.0 × 10-9 E

Question 4

You have 0.20 M HNO2 (Ka = 4.0 × 10-4) and 0.20 M KNO2. You need 1.00 L of a buffered solution at a pH of 3.00. What volumes of each solution do you add together to make this buffered solution?

Accepted Answer

714 mL of

Question 5

Which of the following will not produce a buffered solution?

Accepted Answer

A)  100 mL of 0.1 M Na2CO3 and 50 mL of 0.1 M HCl 
B)  100 mL of 0.1 M NaHCO3 and 25 mL of 0.2 M HCl 
C)  100 mL of 0.1 M Na2CO3 and 75 mL of 0.2 M HCl 
D)  50 mL of 0.2 M Na2CO3 and 5 mL of 1.0 M HCl 
E)  100 mL of 0.1 M Na2CO3 and 50 mL of 0.1 M NaOH 
A)  100 mL of 0.1 M Na2CO3 and 50 mL of 0.1 M HCl 
B)  100 mL of 0.1 M NaHCO3 and 25 mL of 0.2 M HCl 
C)  100 mL of 0.1 M Na2CO3 and 75 mL of 0.2 M HCl 
D)  50 mL of 0.2 M Na2CO3 and 5 mL of 1.0 M HCl 
E)  100 mL of 0.1 M Na2CO3 and 50 mL of 0.1 M NaOH

Question 6

Solubility Products (Ksp)
BaSO4
1)5 × 10-9
CoS
5)0 × 10-22
PbSO4
1)3 × 10-8
AgBr
5)0 × 10-13
BaCO3
1)6 × 10-9
Which of the following compounds is the most soluble (in moles per liter)?

Accepted Answer

A)  PbSO4 
B)  BaSO4 
C)  CoS 
D)  AgBr 
E)  BaCO3 
A)  PbSO4 
B)  BaSO4 
C)  CoS 
D)  AgBr 
E)  BaCO3

Question 7

The concentration of OH- in a saturated solution of Mg(OH)2 is 3.6 × 10-4 M. What is Ksp for Mg(OH)2?

Accepted Answer

A)  1.3 × 10-7 
B)  4.7 × 10-11 
C)  1.2 × 10-11 
D)  3.6 × 10-4 
E)  none of these 
A)  1.3 × 10-7 
B)  4.7 × 10-11 
C)  1.2 × 10-11 
D)  3.6 × 10-4 
E)  none of these

Question 8

Calculate the solubility of Ag2CrO4 [Ksp = 9.0 × 10-12] in a 1.0 × 10-2 M AgNO3 solution.

Accepted Answer

A)  1.3 × 10-4 mol/L 
B)  2.3 × 10-8 mol/L 
C)  9.0 × 10-8 mol/L 
D)  9.0 × 10-10 mol/L 
E)  none of these 
A)  1.3 × 10-4 mol/L 
B)  2.3 × 10-8 mol/L 
C)  9.0 × 10-8 mol/L 
D)  9.0 × 10-10 mol/L 
E)  none of these

Question 9

A 200.0-mL sample of the weak acid HS1U1B13S1U1B0A (0.100 M) is titrated with 0.200 M NaOH. What are the major species at each of the following points in the titration? (Water is always assumed to be a major species.)
-After 75.0 mL of 0.200 M NaOH is added

Accepted Answer

A)  H2A- 
B)  HA2- 
C)  H3A, H2A- 
D)  H2A-, HA2- 
E)  H3A 
A)  H2A- 
B)  HA2- 
C)  H3A, H2A- 
D)  H2A-, HA2- 
E)  H3A

Question 10

A 50.0-mL solution of the acid H3A (Ka1 = 1.0 × 10-6 , Ka2 = 1.0 × 10-9, and Ka3 = 1.0 × 10-12.) is titrated with 0.050 M KOH. The second equivalence point is reached at 25.0 mL of base. Calculate the original concentration of H3A and the volume of 0.050 M KOH needed to reach a pH of 6.70.

Accepted Answer

[H₃A] = 0.0

Question 11

The value of Ksp for AgI is 1.5 × 10-16. Calculate the solubility, in moles per liter, of AgI in a 0.28 M NaI solution.

Accepted Answer

A)  1.2 × 10-8 mol/L 
B)  5.4 × 10-16 mol/L 
C)  2.1 × 10-9 mol/L 
D)  4.2 × 10-17 mol/L 
E)  2.3 × 10-8 mol/L 
A)  1.2 × 10-8 mol/L 
B)  5.4 × 10-16 mol/L 
C)  2.1 × 10-9 mol/L 
D)  4.2 × 10-17 mol/L 
E)  2.3 × 10-8 mol/L

Question 12

Calculate the pH when 200.0 mL of a 1.00 M solution of HS1U1B12S1U1B0A (KS1U1B1a1S1U1B0 = 1.0 × 10S1U1P1-6S1S1P0, KS1U1B1a2S1U1B0 = 1.0 × 10S1U1P1-10S1S1P0) is titrated with the following volumes of 1.00 M NaOH.
-250.0 mL of 1.00 M NaOH

Accepted Answer

A)  10.00 
B)  9.52 
C)  8.00 
D)  9.00 
E)  none of these 
A)  10.00 
B)  9.52 
C)  8.00 
D)  9.00 
E)  none of these

Question 13

A 50.00-mL sample of 0.100 M KOH is titrated with 0.100 M HNO3. Calculate the pH of the solution after the 52.00 mL of HNO3 is added.

Accepted Answer

A)  6.50 
B)  3.01 
C)  2.41 
D)  2.71 
E)  none of these 
A)  6.50 
B)  3.01 
C)  2.41 
D)  2.71 
E)  none of these

Question 14

A solution contains 25 mmol of H3PO4 and 10. mmol of NaH2PO4. What volume of 2.0 M NaOH must be added to reach the second equivalence point of the titration of the H3PO4 with NaOH?

Accepted Answer

A) 60. mL 
B) 30. mL 
C)  5.0 mL 
D)  12 mL 
E)  25 mL 
A) 60. mL 
B) 30. mL 
C)  5.0 mL 
D)  12 mL 
E)  25 mL

Question 15

How many moles of HCl(g) must be added to 1.0 L of 2.0 M NaOH to achieve a pH of 0.00? (Neglect any volume change.)

Accepted Answer

A)  3.0 mol 
B)  10. mol 
C)  1.0 mol 
D)  2.0 mol 
E)  none of these 
A)  3.0 mol 
B)  10. mol 
C)  1.0 mol 
D)  2.0 mol 
E)  none of these

Question 16

Derive the Henderson-Hasselbalch equation from the Ka expression. Explain the assumptions inherent in the Henderson-Hasselbalch equation.

Accepted Answer

See Sectio

Question 17

Silver acetate (AgC2H3O2) is a sparingly soluble salt with Ksp = 1.9 × 10-3. Consider a saturated solution in equilibrium with the solid salt. Compare the effects on the solubility of adding to the solution either the acid HNO3 or the base NH3.

Accepted Answer

A)  NH3 would increase the solubility, but HNO3 would decrease it. 
B)  NH3 would decrease the solubility, but HNO3 would increase it. 
C)  NH3 would increase the solubility, but HNO3 would have virtually no effect. 
D)  Either substance would decrease the solubility. 
E)  Either substance would increase the solubility. 
A)  NH3 would increase the solubility, but HNO3 would decrease it. 
B)  NH3 would decrease the solubility, but HNO3 would increase it. 
C)  NH3 would increase the solubility, but HNO3 would have virtually no effect. 
D)  Either substance would decrease the solubility. 
E)  Either substance would increase the solubility.

Question 18

What is the pH of a solution that results when 0.012 mol HNO3 is added to 610.0 mL of a solution that is 0.26 M in aqueous ammonia and 0.46M in ammonium nitrate. Assume no volume change. (Kb for NH3 = 1.8 × 10-5.)

Accepted Answer

A)  8.96 
B)  9.56 
C)  5.04 
D)  9.01 
E)  4.44 
A)  8.96 
B)  9.56 
C)  5.04 
D)  9.01 
E)  4.44

Question 19

A 200.0-mL sample of the weak acid HS1U1B13S1U1B0A (0.100 M) is titrated with 0.200 M NaOH. What are the major species at each of the following points in the titration? (Water is always assumed to be a major species.)
-After 100.0 mL of 0.200 M NaOH is added

Accepted Answer

A)  H3A, HA2-, A3- 
B)  H2A-, HA2- 
C)  H3A, H2A- 
D)  H2A- 
E)  HA2- 
A)  H3A, HA2-, A3- 
B)  H2A-, HA2- 
C)  H3A, H2A- 
D)  H2A- 
E)  HA2-

Question 20

You dissolve 1.22 g of an unknown diprotic acid in 155.0 mL of H2O. This solution is just neutralized by 6.22 mL of a 1.23 M NaOH solution. What is the molar mass of the unknown acid?

Accepted Answer

A)  1.33 × 102 g/mol 
B)  3.19 × 102 g/mol 
C)  3.09 × 102 g/mol 
D)  1.59 × 102 g/mol 
E)  1.96 × 102 g/mol 
A)  1.33 × 102 g/mol 
B)  3.19 × 102 g/mol 
C)  3.09 × 102 g/mol 
D)  1.59 × 102 g/mol 
E)  1.96 × 102 g/mol

A 0.210-g sample of an acid (molar mass = 192 g/mol) is titrated with 30.5 mL of 0.108 M NaOH to a phenolphthalein endpoint. The formula of the acid is

Calculate the pH at the equivalence point for the titration of 1.0 M ethylamine, C₂H₅NH₂, by 1.0 M perchloric acid, HClO₄. (pK_b for C₂H₅NH₂ = 3.25)

The solubility of M(OH)₂ in 0.010 M KOH is 1.0 × 10^-5 mol/L. What is K_sp for M(OH)₂?

You have 0.20 M HNO₂ (K_a = 4.0 × 10^-4) and 0.20 M KNO₂. You need 1.00 L of a buffered solution at a pH of 3.00. What volumes of each solution do you add together to make this buffered solution?

Which of the following will not produce a buffered solution?

Solubility Products (K_sp) BaSO₄ 1)5 × 10^-9 CoS 5)0 × 10^-22 PbSO₄ 1)3 × 10^-8 AgBr 5)0 × 10^-13 BaCO₃ 1)6 × 10^-9 Which of the following compounds is the most soluble (in moles per liter)?

The concentration of OH^- in a saturated solution of Mg(OH)₂ is 3.6 × 10^-4 M. What is K_sp for Mg(OH)₂?

Calculate the solubility of Ag₂CrO₄ [K_sp = 9.0 × 10^-12] in a 1.0 × 10^-2 M AgNO₃ solution.

A 200.0-mL sample of the weak acid H₃A (0.100 M) is titrated with 0.200 M NaOH. What are the major species at each of the following points in the titration? (Water is always assumed to be a major species.) -After 75.0 mL of 0.200 M NaOH is added

The value of K_sp for AgI is 1.5 × 10^-16. Calculate the solubility, in moles per liter, of AgI in a 0.28 M NaI solution.

Calculate the pH when 200.0 mL of a 1.00 M solution of H₂A (K_a1 = 1.0 × 10^-6, K_a2 = 1.0 × 10^-10) is titrated with the following volumes of 1.00 M NaOH. -250.0 mL of 1.00 M NaOH

A 50.00-mL sample of 0.100 M KOH is titrated with 0.100 M HNO₃. Calculate the pH of the solution after the 52.00 mL of HNO₃ is added.

A solution contains 25 mmol of H₃PO₄ and 10. mmol of NaH₂PO₄. What volume of 2.0 M NaOH must be added to reach the second equivalence point of the titration of the H₃PO₄ with NaOH?

How many moles of HCl(g) must be added to 1.0 L of 2.0 M NaOH to achieve a pH of 0.00? (Neglect any volume change.)

Derive the Henderson-Hasselbalch equation from the K_a expression. Explain the assumptions inherent in the Henderson-Hasselbalch equation.

Silver acetate (AgC₂H₃O₂) is a sparingly soluble salt with K_sp = 1.9 × 10^-3. Consider a saturated solution in equilibrium with the solid salt. Compare the effects on the solubility of adding to the solution either the acid HNO₃ or the base NH₃.

What is the pH of a solution that results when 0.012 mol HNO₃ is added to 610.0 mL of a solution that is 0.26 M in aqueous ammonia and 0.46M in ammonium nitrate. Assume no volume change. (K_b for NH₃ = 1.8 × 10^-5.)

A 200.0-mL sample of the weak acid H₃A (0.100 M) is titrated with 0.200 M NaOH. What are the major species at each of the following points in the titration? (Water is always assumed to be a major species.) -After 100.0 mL of 0.200 M NaOH is added

You dissolve 1.22 g of an unknown diprotic acid in 155.0 mL of H₂O. This solution is just neutralized by 6.22 mL of a 1.23 M NaOH solution. What is the molar mass of the unknown acid?

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Bonding: General Concepts

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Exam 8: Applications of Aqueous Equilibria

A 0.210-g sample of an acid (molar mass = 192 g/mol) is titrated with 30.5 mL of 0.108 M NaOH to a phenolphthalein endpoint. The formula of the acid is

Calculate the pH at the equivalence point for the titration of 1.0 M ethylamine, C2H5NH2, by 1.0 M perchloric acid, HClO4. (pKb for C2H5NH2 = 3.25)

The solubility of M(OH)2 in 0.010 M KOH is 1.0 × 10-5 mol/L. What is Ksp for M(OH)2?

You have 0.20 M HNO2 (Ka = 4.0 × 10-4) and 0.20 M KNO2. You need 1.00 L of a buffered solution at a pH of 3.00. What volumes of each solution do you add together to make this buffered solution?

Which of the following will not produce a buffered solution?

Solubility Products (Ksp) BaSO4 1)5 × 10-9 CoS 5)0 × 10-22 PbSO4 1)3 × 10-8 AgBr 5)0 × 10-13 BaCO3 1)6 × 10-9 Which of the following compounds is the most soluble (in moles per liter)?

The concentration of OH- in a saturated solution of Mg(OH)2 is 3.6 × 10-4 M. What is Ksp for Mg(OH)2?

Calculate the solubility of Ag2CrO4 [Ksp = 9.0 × 10-12] in a 1.0 × 10-2 M AgNO3 solution.

A 200.0-mL sample of the weak acid H3A (0.100 M) is titrated with 0.200 M NaOH. What are the major species at each of the following points in the titration? (Water is always assumed to be a major species.) -After 75.0 mL of 0.200 M NaOH is added

A 50.0-mL solution of the acid H3A (Ka1 = 1.0 × 10-6 , Ka2 = 1.0 × 10-9, and Ka3 = 1.0 × 10-12.) is titrated with 0.050 M KOH. The second equivalence point is reached at 25.0 mL of base. Calculate the original concentration of H3A and the volume of 0.050 M KOH needed to reach a pH of 6.70.

The value of Ksp for AgI is 1.5 × 10-16. Calculate the solubility, in moles per liter, of AgI in a 0.28 M NaI solution.

Calculate the pH when 200.0 mL of a 1.00 M solution of H2A (Ka1 = 1.0 × 10-6, Ka2 = 1.0 × 10-10) is titrated with the following volumes of 1.00 M NaOH. -250.0 mL of 1.00 M NaOH

A 50.00-mL sample of 0.100 M KOH is titrated with 0.100 M HNO3. Calculate the pH of the solution after the 52.00 mL of HNO3 is added.

A solution contains 25 mmol of H3PO4 and 10. mmol of NaH2PO4. What volume of 2.0 M NaOH must be added to reach the second equivalence point of the titration of the H3PO4 with NaOH?

How many moles of HCl(g) must be added to 1.0 L of 2.0 M NaOH to achieve a pH of 0.00? (Neglect any volume change.)

Derive the Henderson-Hasselbalch equation from the Ka expression. Explain the assumptions inherent in the Henderson-Hasselbalch equation.

Silver acetate (AgC2H3O2) is a sparingly soluble salt with Ksp = 1.9 × 10-3. Consider a saturated solution in equilibrium with the solid salt. Compare the effects on the solubility of adding to the solution either the acid HNO3 or the base NH3.

What is the pH of a solution that results when 0.012 mol HNO3 is added to 610.0 mL of a solution that is 0.26 M in aqueous ammonia and 0.46M in ammonium nitrate. Assume no volume change. (Kb for NH3 = 1.8 × 10-5.)

A 200.0-mL sample of the weak acid H3A (0.100 M) is titrated with 0.200 M NaOH. What are the major species at each of the following points in the titration? (Water is always assumed to be a major species.) -After 100.0 mL of 0.200 M NaOH is added

You dissolve 1.22 g of an unknown diprotic acid in 155.0 mL of H2O. This solution is just neutralized by 6.22 mL of a 1.23 M NaOH solution. What is the molar mass of the unknown acid?

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Types of Chemical Reactions and Solution Stoichiometry

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Quantum Mechanics and Atomic Theory

Bonding: General Concepts

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Calculate the pH at the equivalence point for the titration of 1.0 M ethylamine, C₂H₅NH₂, by 1.0 M perchloric acid, HClO₄. (pK_b for C₂H₅NH₂ = 3.25)

The solubility of M(OH)₂ in 0.010 M KOH is 1.0 × 10^-5 mol/L. What is K_sp for M(OH)₂?

You have 0.20 M HNO₂ (K_a = 4.0 × 10^-4) and 0.20 M KNO₂. You need 1.00 L of a buffered solution at a pH of 3.00. What volumes of each solution do you add together to make this buffered solution?

Solubility Products (K_sp) BaSO₄ 1)5 × 10^-9 CoS 5)0 × 10^-22 PbSO₄ 1)3 × 10^-8 AgBr 5)0 × 10^-13 BaCO₃ 1)6 × 10^-9 Which of the following compounds is the most soluble (in moles per liter)?

The concentration of OH^- in a saturated solution of Mg(OH)₂ is 3.6 × 10^-4 M. What is K_sp for Mg(OH)₂?

Calculate the solubility of Ag₂CrO₄ [K_sp = 9.0 × 10^-12] in a 1.0 × 10^-2 M AgNO₃ solution.

A 200.0-mL sample of the weak acid H₃A (0.100 M) is titrated with 0.200 M NaOH. What are the major species at each of the following points in the titration? (Water is always assumed to be a major species.) -After 75.0 mL of 0.200 M NaOH is added

The value of K_sp for AgI is 1.5 × 10^-16. Calculate the solubility, in moles per liter, of AgI in a 0.28 M NaI solution.

Calculate the pH when 200.0 mL of a 1.00 M solution of H₂A (K_a1 = 1.0 × 10^-6, K_a2 = 1.0 × 10^-10) is titrated with the following volumes of 1.00 M NaOH. -250.0 mL of 1.00 M NaOH

A 50.00-mL sample of 0.100 M KOH is titrated with 0.100 M HNO₃. Calculate the pH of the solution after the 52.00 mL of HNO₃ is added.

A solution contains 25 mmol of H₃PO₄ and 10. mmol of NaH₂PO₄. What volume of 2.0 M NaOH must be added to reach the second equivalence point of the titration of the H₃PO₄ with NaOH?

Derive the Henderson-Hasselbalch equation from the K_a expression. Explain the assumptions inherent in the Henderson-Hasselbalch equation.

Silver acetate (AgC₂H₃O₂) is a sparingly soluble salt with K_sp = 1.9 × 10^-3. Consider a saturated solution in equilibrium with the solid salt. Compare the effects on the solubility of adding to the solution either the acid HNO₃ or the base NH₃.

What is the pH of a solution that results when 0.012 mol HNO₃ is added to 610.0 mL of a solution that is 0.26 M in aqueous ammonia and 0.46M in ammonium nitrate. Assume no volume change. (K_b for NH₃ = 1.8 × 10^-5.)

A 200.0-mL sample of the weak acid H₃A (0.100 M) is titrated with 0.200 M NaOH. What are the major species at each of the following points in the titration? (Water is always assumed to be a major species.) -After 100.0 mL of 0.200 M NaOH is added

You dissolve 1.22 g of an unknown diprotic acid in 155.0 mL of H₂O. This solution is just neutralized by 6.22 mL of a 1.23 M NaOH solution. What is the molar mass of the unknown acid?