Question 1

What is the molarity of a sodium hydroxide solution if 25.0 mL of this solution reacts exactly with 22.30 mL of 0.253 M sulfuric acid?

Accepted Answer

A)  0.284 M 
B)  0.451 M 
C)  0.567 M 
D)  0.226 M 
E)  0.113 M

Question 2

You are given a solution of the weak base Novocain, Nvc. Its pH is 11.00. You add to the solution a small amount of a salt containing the conjugate acid of Novocain, NvcH+. Which statement is true?

Accepted Answer

A)  The pH and the pOH remain unchanged. 
B)  The pH and the pOH both decrease. 
C)  The pH and the pOH both increase. 
D)  The pH increases and pOH decreases. 
E)  The pH decreases and the pOH increases.

Question 3

A titration of 100.0 mL of 1.00 M malonic acid (HS1U1B12S1U1B0A) was done with 1.00 M NaOH. For malonic acid, KS1U1B1a1S1U1B0 = 1.49 × 10S1U1P1-2S1S1P0, KS1U1B1a2S1U1B0 = 2.03 × 10S1U1P1-6S1S1P0.
-Calculate [H+] after 300.0 mL of 1.00 M NaOH has been added.

Accepted Answer

A)  1.00 × 10-7 M 
B)  4.00 × 10-14 M 
C)  1.41 × 10-10 M 
D)  1.00 M 
E)  none of these

Question 4

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.
-0 mL of 1.00 M NaOH

Accepted Answer

A)  3.00 
B)  6.00 
C)  0 
D)  3.35 
E)  none of these

Question 5

Consider the titration of 100.0 mL of 0.250 M aniline (Kb = 3.8 × 10-10) with 0.500 M HCl. Calculate the pH of the solution at the stoichiometric point.

Accepted Answer

A)  8.70 
B)  2.68 
C)  11.62 
D)  -0.85 
E)  none of these

Question 6

Calculate the concentration of [H+] of a buffered solution containing 5.0 × 10−4 M HCN (Ka = 6.2 × 10−10) and 1.5 × 10−4 M NaCN.

Accepted Answer

A)  3.06 × 10−9 M​ 
B)  ​0.22 × 10−9 M 
C)  2.07 × 10−9 M 
D)  4.12 × 10−9 M 
E)  4.58 × 10−9 M

Question 7

A 50.0-mL sample of 2.0 × 10-4 M CuNO3 is added to 50.0 mL of 4.0 M NaCN. Cu+ reacts with CN- to form the complex ion Cu(CN)32-:  Calculate the solubility of CuBr(s) (Ksp = 1.0 × 10-5) in 1.0 L of 1.0 M NaCN.

Accepted Answer

A)  0.33 mol/L 
B)  1.0 × 10-6 mol/L 
C)  1.0 × 103 mol/L 
D)  1.0 mol/L 
E)  none of these

Question 8

Differentiate between the equivalence point and the endpoint in an acid-base titration.

Accepted Answer

The answer of Differentiate between the equivalence point and the...

Question 9

A 200-mL solution contains 0.018 mol each of I-, Br-, and Cl-. When the solution is mixed with 200 mL of 0.24 M AgNO3, how much AgCl(s) precipitates out?

Accepted Answer

A)  2.6 g 
B)  0.0 g 
C)  3.3 g 
D)  5.0 g 
E)  1.7 g

Question 10

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.
-200.0 mL of 1.00 M NaOH

Accepted Answer

A)  9.50 
B)  6.48 
C)  6.00 
D)  8.00 
E)  none of these

Question 11

Which of the following salts shows the lowest solubility in water? Ksp values are as follows:
Ag2S = 1.6 × 10-49; Bi2S3 = 1.0 × 10-72; HgS = 1.6 × 10-54; Mg(OH)2 = 8.9 × 10-12; MnS = 2.3 × 10-13)

Accepted Answer

A)  HgS 
B)  MnS 
C)  Bi2S3 
D)  Ag2S 
E)  Mg(OH)2

Question 12

You have solutions of 0.200 M HNO2 and 0.200 M KNO2 (Ka for HNO2 = 4.00 × 10-4). A buffer of pH 3.000 is needed. What volumes of HNO2 and KNO2 are required to make 1 L of buffered solution?

Accepted Answer

A)  286 mL HNO2; 714 mL KNO2 
B)  714 mL HNO2; 286 mL KNO2 
C)  413 mL HNO2; 587 mL KNO2 
D)  500 mL of each 
E)  587 mL HNO2; 413 mL KNO2

Question 13

A 0.012-mol sample of Na2SO4 is added to 400 mL of each of two solutions. One solution contains 1.5 × 10-3 M BaCl2; the other contains 1.5 × 10-3 M CaCl2. Ksp for BaSO4 = 1.5 × 10-9 and Ksp for CaSO4 = 6.1 × 10-5. Which of the following statements is true?

Accepted Answer

A)  Both BaSO4 and CaSO4 would precipitate. 
B)  Not enough information is given to determine whether precipitation would occur. 
C)  CaSO4 would precipitate but BaSO4 would not. 
D)  BaSO4 would precipitate but CaSO4 would not. 
E)  Neither BaSO4 nor CaSO4 would precipitate.

Question 14

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 300.0 mL of 0.200 M NaOH is added

Accepted Answer

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

Question 15

Consider the following information about the diprotic acid ascorbic acid (HS1U1B12S1U1B0As for short, molar mass = 176.1).  The titration curve for disodium ascorbate, NaS1U1B12S1U1B0As, with standard HCl is shown below: 
-What is the pH at point I (V1/2 HCl added)?

Accepted Answer

A)  7.95 
B)  12.39 
C)  10 
D)  11.79 
E)  none of these

Question 16

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.
-300.0 mL of 1.00 M NaOH

Accepted Answer

A)  10.00 
B)  11.21 
C)  9.50 
D)  9.30 
E)  none of these

Question 17

The contents of the flask are transferred quantitatively to a 2L volumetric. 100ml of 1 M HCL is added and the flask filled to the mark with water. There is still observable solid calcium hydroxide in the bottom of the new flask. What is the pH of this solution?

Accepted Answer

A)  2.94 
B)  12.14 
C)  2.16 
D)  7.00 
E)  11.83

Question 18

A 50.00-mL sample of 0.100 M Ca(NO3)2 is mixed with 50.00 mL of 0.200 M NaF. When the system has come to equilibrium, which of the following sets of conditions will hold? The Ksp for CaF2 is 4.0 × 10-11.

Accepted Answer

A)  10.0 × 10-3 1.3 × 10-5 M 1.3 × 10-5 M 
B)  5.0 × 10-3 3.5 × 10-4 M 7.0 × 10-4 M 
C)  5.0 × 10-3 2.2 × 10-4 M 4.3 × 10-4 M 
D)  5.0 × 10-3 3.5 × 10-4 M 4.3 × 10-4 M 
E)  5.0 × 10-3 3.4 × 10-9 M 5.0 × 10-2 M

Question 19

In the titration of 100.0 mL of a 0.200 M solution of H2A (Ka1 = 1.0 × 10-5, Ka2 = 1.0 × 10-8), what volume of 0.400 M NaOH must be added to reach a pH of 5.00?

Accepted Answer

A)  25.0 mL 
B)  100.0 mL 
C)  0 mL 
D)  150.0 mL 
E)  50.0 mL

Question 20

One milliliter (1.00 mL) of acid taken from a lead storage battery is pipetted into a flask. Water and phenolphthalein indicator are added, and the solution is titrated with 0.38 M NaOH until a pink color appears; 15.8 mL is required. Find, to within 5%, the number of grams of H2SO4 (formula weight = 98) present in 1 L of the battery acid.

Accepted Answer

A)  480 g 
B)  240 g 
C)  580 g 
D)  290 g 
E)  750 g

Exam 8: Applications of Aqueous Equilibria

What is the molarity of a sodium hydroxide solution if 25.0 mL of this solution reacts exactly with 22.30 mL of 0.253 M sulfuric acid?

You are given a solution of the weak base Novocain, Nvc. Its pH is 11.00. You add to the solution a small amount of a salt containing the conjugate acid of Novocain, NvcH⁺. Which statement is true?

A titration of 100.0 mL of 1.00 M malonic acid (H₂A) was done with 1.00 M NaOH. For malonic acid, K_a1 = 1.49 × 10^-2, K_a2 = 2.03 × 10^-6. -Calculate [H⁺] after 300.0 mL of 1.00 M NaOH has been added.

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. -0 mL of 1.00 M NaOH

Consider the titration of 100.0 mL of 0.250 M aniline (K_b = 3.8 × 10^-10) with 0.500 M HCl. Calculate the pH of the solution at the stoichiometric point.

Calculate the concentration of [H⁺] of a buffered solution containing 5.0 × 10⁻⁴ M HCN (K_a = 6.2 × 10⁻¹⁰) and 1.5 × 10⁻⁴ M NaCN.

A 50.0-mL sample of 2.0 × 10^-4 M CuNO₃ is added to 50.0 mL of 4.0 M NaCN. Cu⁺ reacts with CN^- to form the complex ion Cu(CN) ₃^2-: Calculate the solubility of CuBr(s) (K_sp = 1.0 × 10^-5) in 1.0 L of 1.0 M NaCN.

Differentiate between the equivalence point and the endpoint in an acid-base titration.

A 200-mL solution contains 0.018 mol each of I^-, Br^-, and Cl^-. When the solution is mixed with 200 mL of 0.24 M AgNO₃, how much AgCl(s) precipitates out?

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. -200.0 mL of 1.00 M NaOH

Which of the following salts shows the lowest solubility in water? K_sp values are as follows: Ag₂S = 1.6 × 10^-49; Bi₂S₃ = 1.0 × 10^-72; HgS = 1.6 × 10^-54; Mg(OH) ₂ = 8.9 × 10^-12; MnS = 2.3 × 10^-13)

You have solutions of 0.200 M HNO₂ and 0.200 M KNO₂ (K_a for HNO₂ = 4.00 × 10^-4) . A buffer of pH 3.000 is needed. What volumes of HNO₂ and KNO₂ are required to make 1 L of buffered solution?

A 0.012-mol sample of Na₂SO₄ is added to 400 mL of each of two solutions. One solution contains 1.5 × 10^-3 M BaCl₂; the other contains 1.5 × 10^-3 M CaCl₂. K_sp for BaSO₄ = 1.5 × 10^-9 and K_sp for CaSO₄ = 6.1 × 10^-5. Which of the following statements is true?

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 300.0 mL of 0.200 M NaOH is added

Consider the following information about the diprotic acid ascorbic acid (H₂As for short, molar mass = 176.1) . The titration curve for disodium ascorbate, Na₂As, with standard HCl is shown below: -What is the pH at point I (V₁/2 HCl added) ?

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. -300.0 mL of 1.00 M NaOH

The contents of the flask are transferred quantitatively to a 2L volumetric. 100ml of 1 M HCL is added and the flask filled to the mark with water. There is still observable solid calcium hydroxide in the bottom of the new flask. What is the pH of this solution?

A 50.00-mL sample of 0.100 M Ca(NO₃) ₂ is mixed with 50.00 mL of 0.200 M NaF. When the system has come to equilibrium, which of the following sets of conditions will hold? The K_sp for CaF₂ is 4.0 × 10^-11.

In the titration of 100.0 mL of a 0.200 M solution of H₂A (K_a1 = 1.0 × 10^-5, K_a2 = 1.0 × 10^-8) , what volume of 0.400 M NaOH must be added to reach a pH of 5.00?

Exam 8: Applications of Aqueous Equilibria

What is the molarity of a sodium hydroxide solution if 25.0 mL of this solution reacts exactly with 22.30 mL of 0.253 M sulfuric acid?

You are given a solution of the weak base Novocain, Nvc. Its pH is 11.00. You add to the solution a small amount of a salt containing the conjugate acid of Novocain, NvcH+. Which statement is true?

A titration of 100.0 mL of 1.00 M malonic acid (H2A) was done with 1.00 M NaOH. For malonic acid, Ka1 = 1.49 × 10-2, Ka2 = 2.03 × 10-6. -Calculate [H+] after 300.0 mL of 1.00 M NaOH has been added.

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. -0 mL of 1.00 M NaOH

Consider the titration of 100.0 mL of 0.250 M aniline (Kb = 3.8 × 10-10) with 0.500 M HCl. Calculate the pH of the solution at the stoichiometric point.

Calculate the concentration of [H+] of a buffered solution containing 5.0 × 10−4 M HCN (Ka = 6.2 × 10−10) and 1.5 × 10−4 M NaCN.

A 50.0-mL sample of 2.0 × 10-4 M CuNO3 is added to 50.0 mL of 4.0 M NaCN. Cu+ reacts with CN- to form the complex ion Cu(CN) 32-: Calculate the solubility of CuBr(s) (Ksp = 1.0 × 10-5) in 1.0 L of 1.0 M NaCN.

Differentiate between the equivalence point and the endpoint in an acid-base titration.

A 200-mL solution contains 0.018 mol each of I-, Br-, and Cl-. When the solution is mixed with 200 mL of 0.24 M AgNO3, how much AgCl(s) precipitates out?

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. -200.0 mL of 1.00 M NaOH

Which of the following salts shows the lowest solubility in water? Ksp values are as follows: Ag2S = 1.6 × 10-49; Bi2S3 = 1.0 × 10-72; HgS = 1.6 × 10-54; Mg(OH) 2 = 8.9 × 10-12; MnS = 2.3 × 10-13)

You have solutions of 0.200 M HNO2 and 0.200 M KNO2 (Ka for HNO2 = 4.00 × 10-4) . A buffer of pH 3.000 is needed. What volumes of HNO2 and KNO2 are required to make 1 L of buffered solution?

A 0.012-mol sample of Na2SO4 is added to 400 mL of each of two solutions. One solution contains 1.5 × 10-3 M BaCl2; the other contains 1.5 × 10-3 M CaCl2. Ksp for BaSO4 = 1.5 × 10-9 and Ksp for CaSO4 = 6.1 × 10-5. Which of the following statements is true?

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 300.0 mL of 0.200 M NaOH is added

Consider the following information about the diprotic acid ascorbic acid (H2As for short, molar mass = 176.1) . The titration curve for disodium ascorbate, Na2As, with standard HCl is shown below: -What is the pH at point I (V1/2 HCl added) ?

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. -300.0 mL of 1.00 M NaOH

The contents of the flask are transferred quantitatively to a 2L volumetric. 100ml of 1 M HCL is added and the flask filled to the mark with water. There is still observable solid calcium hydroxide in the bottom of the new flask. What is the pH of this solution?

A 50.00-mL sample of 0.100 M Ca(NO3) 2 is mixed with 50.00 mL of 0.200 M NaF. When the system has come to equilibrium, which of the following sets of conditions will hold? The Ksp for CaF2 is 4.0 × 10-11.

In the titration of 100.0 mL of a 0.200 M solution of H2A (Ka1 = 1.0 × 10-5, Ka2 = 1.0 × 10-8) , what volume of 0.400 M NaOH must be added to reach a pH of 5.00?

You are given a solution of the weak base Novocain, Nvc. Its pH is 11.00. You add to the solution a small amount of a salt containing the conjugate acid of Novocain, NvcH⁺. Which statement is true?

A titration of 100.0 mL of 1.00 M malonic acid (H₂A) was done with 1.00 M NaOH. For malonic acid, K_a1 = 1.49 × 10^-2, K_a2 = 2.03 × 10^-6. -Calculate [H⁺] after 300.0 mL of 1.00 M NaOH has been added.

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. -0 mL of 1.00 M NaOH

Consider the titration of 100.0 mL of 0.250 M aniline (K_b = 3.8 × 10^-10) with 0.500 M HCl. Calculate the pH of the solution at the stoichiometric point.

Calculate the concentration of [H⁺] of a buffered solution containing 5.0 × 10⁻⁴ M HCN (K_a = 6.2 × 10⁻¹⁰) and 1.5 × 10⁻⁴ M NaCN.

A 50.0-mL sample of 2.0 × 10^-4 M CuNO₃ is added to 50.0 mL of 4.0 M NaCN. Cu⁺ reacts with CN^- to form the complex ion Cu(CN) ₃^2-: Calculate the solubility of CuBr(s) (K_sp = 1.0 × 10^-5) in 1.0 L of 1.0 M NaCN.

A 200-mL solution contains 0.018 mol each of I^-, Br^-, and Cl^-. When the solution is mixed with 200 mL of 0.24 M AgNO₃, how much AgCl(s) precipitates out?

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. -200.0 mL of 1.00 M NaOH

Which of the following salts shows the lowest solubility in water? K_sp values are as follows: Ag₂S = 1.6 × 10^-49; Bi₂S₃ = 1.0 × 10^-72; HgS = 1.6 × 10^-54; Mg(OH) ₂ = 8.9 × 10^-12; MnS = 2.3 × 10^-13)

You have solutions of 0.200 M HNO₂ and 0.200 M KNO₂ (K_a for HNO₂ = 4.00 × 10^-4) . A buffer of pH 3.000 is needed. What volumes of HNO₂ and KNO₂ are required to make 1 L of buffered solution?

A 0.012-mol sample of Na₂SO₄ is added to 400 mL of each of two solutions. One solution contains 1.5 × 10^-3 M BaCl₂; the other contains 1.5 × 10^-3 M CaCl₂. K_sp for BaSO₄ = 1.5 × 10^-9 and K_sp for CaSO₄ = 6.1 × 10^-5. Which of the following statements is true?

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 300.0 mL of 0.200 M NaOH is added

Consider the following information about the diprotic acid ascorbic acid (H₂As for short, molar mass = 176.1) . The titration curve for disodium ascorbate, Na₂As, with standard HCl is shown below: -What is the pH at point I (V₁/2 HCl added) ?

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. -300.0 mL of 1.00 M NaOH

A 50.00-mL sample of 0.100 M Ca(NO₃) ₂ is mixed with 50.00 mL of 0.200 M NaF. When the system has come to equilibrium, which of the following sets of conditions will hold? The K_sp for CaF₂ is 4.0 × 10^-11.

In the titration of 100.0 mL of a 0.200 M solution of H₂A (K_a1 = 1.0 × 10^-5, K_a2 = 1.0 × 10^-8) , what volume of 0.400 M NaOH must be added to reach a pH of 5.00?