Question 1

Which of the following acids (listed with Ka values) and their conjugate base would be the best choice to make a buffer with a pH of 5.20?

Accepted Answer

A)  C6H5COOH, Ka = 6.5 × 10-5 
B)  HF, Ka = 3.5 × 10-4 
C)  HClO, Ka = 2.9 × 10-8 
D)  HCN, Ka = 4.9 × 10-10 
E)  HClO2, Ka = 1.1 × 10-2 
A)  C6H5COOH, Ka = 6.5 × 10-5 
B)  HF, Ka = 3.5 × 10-4 
C)  HClO, Ka = 2.9 × 10-8 
D)  HCN, Ka = 4.9 × 10-10 
E)  HClO2, Ka = 1.1 × 10-2

Question 2

Identify the compound that is base-insoluble.

Accepted Answer

A)  PbCl2 
B)  As2S 
C)  CoS 
D)  Ca3(PO4)2 
E)  NaCl 
A)  PbCl2 
B)  As2S 
C)  CoS 
D)  Ca3(PO4)2 
E)  NaCl

Question 3

Calculate the pH of a solution formed by mixing 150.0 mL of 0.10 mol L-1 C6H5COOH with 100.0 mL of 0.30 mol L-1 C6H5COONa. The Ka for C6H5COOH is 6.5 × 10-5.

Accepted Answer

A)  4.19 
B)  9.69 
C)  4.49 
D)  4.31 
E)  10.51 
A)  4.19 
B)  9.69 
C)  4.49 
D)  4.31 
E)  10.51

Question 4

Identify the expression for the solubility product constant for BaF2.

Accepted Answer

A)    
B)    
C)  [Ba2+]2[F⁻] 
D)  [Ba2+][F⁻]2 
E)  [Ba2+][F⁻] 
A)    
B)    
C)  [Ba2+]2[F⁻] 
D)  [Ba2+][F⁻]2 
E)  [Ba2+][F⁻]

Question 5

Which of the following solutions represents a good buffer system?

Accepted Answer

A)  a solution that is 0.10 mol L-1 CH3COOH and 0.10 mol L-1 CH3COOLi 
B)  a solution that is 0.10 mol L-1 HF and 0.10 mol L-1 CH3COONa 
C)  a solution that is 0.10 mol L-1 HCl and 0.10 mol L-1 NH4+ 
D)  a solution that is 0.10 mol L-1 NaOH and 0.10 mol L-1 KOH 
E)  a solution that is 0.10 mol L-1 HCl and 0.10 mol L-1 KCl 
A)  a solution that is 0.10 mol L-1 CH3COOH and 0.10 mol L-1 CH3COOLi 
B)  a solution that is 0.10 mol L-1 HF and 0.10 mol L-1 CH3COONa 
C)  a solution that is 0.10 mol L-1 HCl and 0.10 mol L-1 NH4+ 
D)  a solution that is 0.10 mol L-1 NaOH and 0.10 mol L-1 KOH 
E)  a solution that is 0.10 mol L-1 HCl and 0.10 mol L-1 KCl

Question 6

Which of the following is TRUE?

Accepted Answer

A)  The equivalence point is where the amount of acid equals the amount of base during any acid-base titration. 
B)  At the equivalence point, the pH is always 7. 
C)  An indicator is not pH sensitive. 
D)  A titration curve is a plot of pH vs. the [base]/[acid] ratio. 
E)  A titration curve is a plot of pH versus titration time. 
A)  The equivalence point is where the amount of acid equals the amount of base during any acid-base titration. 
B)  At the equivalence point, the pH is always 7. 
C)  An indicator is not pH sensitive. 
D)  A titration curve is a plot of pH vs. the [base]/[acid] ratio. 
E)  A titration curve is a plot of pH versus titration time.

Question 7

Which of the following acids (listed with pKa values) and its conjugate would be the best choice to make a buffer with a pH of 10.40?

Accepted Answer

A)  HC7H5O2, pKa = 4.19 
B)  HF, pKa = 3.46 
C)  HClO, pKa = 7.54 
D)  HCN, pKa = 9.31 
E)  HClO2, pKa = 1.96 
A)  HC7H5O2, pKa = 4.19 
B)  HF, pKa = 3.46 
C)  HClO, pKa = 7.54 
D)  HCN, pKa = 9.31 
E)  HClO2, pKa = 1.96

Question 8

Which one of the following statements is TRUE?

Accepted Answer

A)  A buffer is an aqueous solution composed of two weak acids. 
B)  A buffer can absorb an unlimited amount of acid or base. 
C)  A buffer resists pH change by neutralizing added acids and bases. 
D)  A buffer does not change pH when large amounts of a strong acid or a strong base are added. 
E)  The common ion in a buffer solution does not have any effect on the dissociation of the acidic component of the buffer solution. 
A)  A buffer is an aqueous solution composed of two weak acids. 
B)  A buffer can absorb an unlimited amount of acid or base. 
C)  A buffer resists pH change by neutralizing added acids and bases. 
D)  A buffer does not change pH when large amounts of a strong acid or a strong base are added. 
E)  The common ion in a buffer solution does not have any effect on the dissociation of the acidic component of the buffer solution.

Question 9

Which of the following compounds will have the highest molar solubility in pure water?

Accepted Answer

A)  PbS, Ksp = 9.04 × 10-29 
B)  CuS, Ksp = 1.27 × 10-36 
C)  Al(OH)3, Ksp = 1.3 × 10-33 
D)  ZnS, Ksp = 2 × 10-25 
E)  Ag2S, Ksp = 6 × 10-51 
A)  PbS, Ksp = 9.04 × 10-29 
B)  CuS, Ksp = 1.27 × 10-36 
C)  Al(OH)3, Ksp = 1.3 × 10-33 
D)  ZnS, Ksp = 2 × 10-25 
E)  Ag2S, Ksp = 6 × 10-51

Question 10

A 100.0 mL sample of 0.20 mol L-1 HF is titrated with 0.10 mol L-1 KOH. Determine the pH of the solution after the addition of 400.0 mL of KOH. The Ka of HF is 3.5 × 10-4.

Accepted Answer

A)  13.08 
B)  12.60 
C)  13.85 
D)  12.30 
E)  12.78 
A)  13.08 
B)  12.60 
C)  13.85 
D)  12.30 
E)  12.78

Question 11

Determine the molar solubility of MgCO3 in pure water. Ksp (MgCO3) = 6.82 × 10-6.

Accepted Answer

A)  6.82 × 10-6 mol L-1 
B)  3.41 × 10-6 mol L-1 
C)  4.65 × 10-3 mol L-1 
D)  2.61 × 10-3 mol L-1 
E)  3.25 × 10-4 mol L-1 
A)  6.82 × 10-6 mol L-1 
B)  3.41 × 10-6 mol L-1 
C)  4.65 × 10-3 mol L-1 
D)  2.61 × 10-3 mol L-1 
E)  3.25 × 10-4 mol L-1

Question 12

Calculate the pH of a solution formed by mixing 100.0 mL of 0.20 mol L-1 HClO with 200.0 mL of 0.30 mol L-1 KClO. The Ka for HClO is 2.9 × 10-8.

Accepted Answer

A)  5.99 
B)  8.01 
C)  7.54 
D)  7.06 
E)  6.46 
A)  5.99 
B)  8.01 
C)  7.54 
D)  7.06 
E)  6.46

Question 13

What happens at neutral pH to aluminum hydroxide precipitate?

Accepted Answer

A)  Al(H2O)63+ is formed and the precipitate dissolves. 
B)  Al(H2O)2(OH)4- is formed and the precipitate dissolves. 
C)  Al(OH)3 precipitate is still present. 
D)  Al precipitates. 
E)  Al is formed. 
A)  Al(H2O)63+ is formed and the precipitate dissolves. 
B)  Al(H2O)2(OH)4- is formed and the precipitate dissolves. 
C)  Al(OH)3 precipitate is still present. 
D)  Al precipitates. 
E)  Al is formed.

Question 14

Calculate the pH of a solution formed by mixing 200.0 mL of 0.30 mol L-1 HClO with 100.0 mL of 0.20 mol L-1 KClO. The Ka for HClO is 2.9 × 10-8.

Accepted Answer

A)  5.99 
B)  8.01 
C)  7.54 
D)  7.06 
E)  6.46 
A)  5.99 
B)  8.01 
C)  7.54 
D)  7.06 
E)  6.46

Question 15

Identify the expression for the solubility product constant for Cr2(CO3)3.

Accepted Answer

A)  [Cr3+]2[CO32-]3 
B)    
C)    
D)    
E)  [Cr3+]3[CO32-]2 
A)  [Cr3+]2[CO32-]3 
B)    
C)    
D)    
E)  [Cr3+]3[CO32-]2

Question 16

Match the following.
-pH = pKa

Accepted Answer

A) equivalence point of a weak acid-strong base titration 
B) halfway to equivalence point of a weak acid-strong base titration 
C) equivalence point of a strong acid-strong base titration 
D) equivalence point of a weak base-strong acid titration 
E) three-quarters of the way to second equivalence point of a diprotic acid-strong base titration 
A) equivalence point of a weak acid-strong base titration 
B) halfway to equivalence point of a weak acid-strong base titration 
C) equivalence point of a strong acid-strong base titration 
D) equivalence point of a weak base-strong acid titration 
E) three-quarters of the way to second equivalence point of a diprotic acid-strong base titration

Question 17

A 100.0 mL sample of 0.20 mol L-1 HF is titrated with 0.10 mol L-1 KOH. Determine the pH of the solution after the addition of 200.0 mL of KOH. The Ka of HF is 3.5 × 10-4.

Accepted Answer

A)  9.62 
B)  7.00 
C)  3.46 
D)  10.54 
E)  8.14 
A)  9.62 
B)  7.00 
C)  3.46 
D)  10.54 
E)  8.14

Question 18

Identify the indicator that has two endpoints.

Accepted Answer

A)  phenol red 
B)  thymol blue 
C)  crystal violet 
D)  phenolphthalein 
E)  alizarin yellow R 
A)  phenol red 
B)  thymol blue 
C)  crystal violet 
D)  phenolphthalein 
E)  alizarin yellow R

Question 19

Calculate the molar solubility of thallium chloride (TlCl) in 0. 50 mol L-1 NaCl at 25 °C. Ksp for TlCl is

Accepted Answer

A)  8.5 × 10-5 mol L-1 
B)  3.4 × 10-4 mol L-1 
C)  9.2 × 10-3 mol L-1 
D)  1.3 × 10-2 mol L-1 
A)  8.5 × 10-5 mol L-1 
B)  3.4 × 10-4 mol L-1 
C)  9.2 × 10-3 mol L-1 
D)  1.3 × 10-2 mol L-1

Question 20

Which of the following solutions is a good buffer system?

Accepted Answer

A)  a solution that is 0.10 mol L-1 NaCl and 0.10 mol L-1 HCl 
B)  a solution that is 0.10 mol L-1 HCN and 0.10 mol L-1 LiCN 
C)  a solution that is 0.10 mol L-1 NaOH and 0.10 mol L-1 HNO3 
D)  a solution that is 0.10 mol L-1 HNO3 and 0.10 mol L-1 KNO3 
E)  a solution that is 0.10 mol L-1 HCN and 0.10 mol L-1 NaCl 
A)  a solution that is 0.10 mol L-1 NaCl and 0.10 mol L-1 HCl 
B)  a solution that is 0.10 mol L-1 HCN and 0.10 mol L-1 LiCN 
C)  a solution that is 0.10 mol L-1 NaOH and 0.10 mol L-1 HNO3 
D)  a solution that is 0.10 mol L-1 HNO3 and 0.10 mol L-1 KNO3 
E)  a solution that is 0.10 mol L-1 HCN and 0.10 mol L-1 NaCl

Exam 16: Aqueous Ionic Equilibrium

Which of the following acids (listed with Ka values) and their conjugate base would be the best choice to make a buffer with a pH of 5.20?

Identify the compound that is base-insoluble.

Calculate the pH of a solution formed by mixing 150.0 mL of 0.10 mol L-1 C6H5COOH with 100.0 mL of 0.30 mol L-1 C6H5COONa. The Ka for C6H5COOH is 6.5 × 10-5.

Identify the expression for the solubility product constant for BaF2.

Which of the following solutions represents a good buffer system?

Which of the following is TRUE?

Which of the following acids (listed with pKa values) and its conjugate would be the best choice to make a buffer with a pH of 10.40?

Which one of the following statements is TRUE?

Which of the following compounds will have the highest molar solubility in pure water?

A 100.0 mL sample of 0.20 mol L-1 HF is titrated with 0.10 mol L-1 KOH. Determine the pH of the solution after the addition of 400.0 mL of KOH. The Ka of HF is 3.5 × 10-4.

Determine the molar solubility of MgCO3 in pure water. Ksp (MgCO3) = 6.82 × 10-6.

Calculate the pH of a solution formed by mixing 100.0 mL of 0.20 mol L-1 HClO with 200.0 mL of 0.30 mol L-1 KClO. The Ka for HClO is 2.9 × 10-8.

What happens at neutral pH to aluminum hydroxide precipitate?

Calculate the pH of a solution formed by mixing 200.0 mL of 0.30 mol L-1 HClO with 100.0 mL of 0.20 mol L-1 KClO. The Ka for HClO is 2.9 × 10-8.

Identify the expression for the solubility product constant for Cr2(CO3)3.

Match the following. -pH = pKa

A 100.0 mL sample of 0.20 mol L-1 HF is titrated with 0.10 mol L-1 KOH. Determine the pH of the solution after the addition of 200.0 mL of KOH. The Ka of HF is 3.5 × 10-4.

Identify the indicator that has two endpoints.

Calculate the molar solubility of thallium chloride (TlCl) in 0. 50 mol L-1 NaCl at 25 °C. Ksp for TlCl is

Which of the following solutions is a good buffer system?

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Filters

Which of the following acids (listed with K_a values) and their conjugate base would be the best choice to make a buffer with a pH of 5.20?

Calculate the pH of a solution formed by mixing 150.0 mL of 0.10 mol L^-1 C₆H₅COOH with 100.0 mL of 0.30 mol L^-1 C₆H₅COONa. The K_a for C₆H₅COOH is 6.5 × 10^-5.

Identify the expression for the solubility product constant for BaF₂.

Which of the following acids (listed with pK_a values) and its conjugate would be the best choice to make a buffer with a pH of 10.40?

A 100.0 mL sample of 0.20 mol L^-1 HF is titrated with 0.10 mol L^-1 KOH. Determine the pH of the solution after the addition of 400.0 mL of KOH. The K_a of HF is 3.5 × 10^-4.

Determine the molar solubility of MgCO₃in pure water. K_sp (MgCO₃) = 6.82 × 10^-6.

Calculate the pH of a solution formed by mixing 100.0 mL of 0.20 mol L^-1 HClO with 200.0 mL of 0.30 mol L^-1 KClO. The K_a for HClO is 2.9 × 10^-8.

Calculate the pH of a solution formed by mixing 200.0 mL of 0.30 mol L^-1 HClO with 100.0 mL of 0.20 mol L^-1 KClO. The K_a for HClO is 2.9 × 10^-8.

Identify the expression for the solubility product constant for Cr₂(CO₃)₃.

Match the following. -pH = pK_a

A 100.0 mL sample of 0.20 mol L^-1 HF is titrated with 0.10 mol L^-1 KOH. Determine the pH of the solution after the addition of 200.0 mL of KOH. The K_a of HF is 3.5 × 10^-4.

Calculate the molar solubility of thallium chloride (TlCl) in 0. 50 mol L^-1 NaCl at 25 °C. K_sp for TlCl is