Question 1

A 25.0 mL sample of 0.150 mol L-1 butanoic acid is titrated with a 0.150 mol L-1 NaOH solution. What is the pH after 13.3 mL of base is added? The  of butanoic acid is 1.5 × 10-5.

Accepted Answer

A)  1.34 
B)  4.55 
C)  3.08 
D)  4.77 
E)  4.88

Question 2

Define buffer capacity.

Accepted Answer

A)  Buffer capacity is the amount of acid or base that can be added to a buffer without destroying its effectiveness. 
B)  Buffer capacity is the amount of acid that can be added until all the base in the buffer is consumed. 
C)  Buffer capacity is the amount of base that can be added until all the acid in the buffer is consumed. 
D)  Buffer capacity is the amount of acid that can be added until all the acid in the buffer is consumed. 
E)  Buffer capacity is the amount of base that can be added until all the base in the buffer is consumed.

Question 3

Identify the expression for the solubility product constant for PbCl2.

Accepted Answer

A)   
B)   
C)  [Pb2+][Cl⁻]2 
D)   
E)  [Pb2+]2[Cl⁻]

Question 4

Describe the information necessary (and why) to choose a good indicator for a weak acid-strong base titration.

Accepted Answer

The answer of Describe the information necessary (and why) to...

Question 5

Which of the following is the correct equation relating Q to Ksp for a supersaturated solution?

Accepted Answer

A)  Q > Ksp 
B)  Q sp 
C)  Q = Ksp 
D)  Q ≠ Ksp 
E)  Q ≥ Ksp

Question 6

For a strong acid titrated with a strong base, is the equivalence point acidic, basic, or neutral?

Accepted Answer

The answer of For a strong acid titrated with a...

Question 7

A 100.0 mL sample of 0.18 mol L-1 HClO4 is titrated with 0.27 mol L-1 NaOH. Determine the pH of the solution after the addition of 66.67 mL of NaOH (this is the equivalence point).

Accepted Answer

A)  0.97 
B)  13.03 
C)  2.76 
D)  11.24 
E)  7.00

Question 8

A 1.00 L buffer solution is 0.250 mol L-1 in HF and 0.250 mol L-1 in LiF. Calculate the pH of the solution after the addition of 0.150 moles of solid LiOH. Assume no volume change upon the addition of the base. The Ka for HF is 3.5 × 10-4.

Accepted Answer

A)  3.46 
B)  4.06 
C)  2.85 
D)  3.63 
E)  4.24

Question 9

What is the pH at the equivalence point of a weak base-strong acid titration if 20.00 mL of NaOCl requires 28.30 mL of 0. 50 mol L-1 HCl for complete neutralization? Ka = 3.0 × 10-8 for HOCl.

Accepted Answer

A)  0.30 
B)  3. 18 
C)  3.76 
D)  4. 03

Question 10

The molar solubility of Ag2S is 1.26 × 10-16 mol L-1 in pure water. Calculate the Ksp for Ag2S.

Accepted Answer

A)  1.59 × 10-32 
B)  1.12 × 10-8 
C)  6.81 × 10-63 
D)  3.78 × 10-12 
E)  8.00 × 10-48

Question 11

A 25.0 mL sample of 0.150 mol L-1 acetic acid is titrated with a 0.150 mol L-1 NaOH solution. What is the pH after 26.0 mL of base is added? The  of acetic acid is 1.8 × 10-5.

Accepted Answer

A)  2.54 
B)  11.47 
C)  7.00 
D)  4.74 
E)  10.18

Question 12

A 100.0 mL sample of 0.10 mol L-1 NH3 is titrated with 0.10 mol L-1 HNO3. Determine the pH of the solution after the addition of 200.0 mL of HNO3. The Kb of NH3 is 1.8 × 10-5.

Accepted Answer

A)  6.44 
B)  1.48 
C)  2.00 
D)  12.52 
E)  12.00

Question 13

You wish to prepare a buffer containing CH3COOH with a pH of 4.24. If the pKa of acetic acid is 4.74, what ratio of [CH3COO⁻]/[CH3COOH] must you use?

Accepted Answer

A)  0.10 
B)  0.50 
C)  0.32 
D)  2.0 
E)  2.8

Question 14

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 2.34?

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

Question 15

A solution contains 0.021 mol L-1 Cl⁻ and 0.017 mol L-1 I⁻. A solution containing copper(I) ions is added to selectively precipitate one of the ions. At what concentration of copper(I) ion will a precipitate begin to form? What is the identity of the precipitate? Ksp(CuCl) = 1.0 × 10-6, Ksp(CuI) = 5.1 × 10-12.

Accepted Answer

A)  3.0 × 10-10 mol L-1, CuI 
B)  3.0 × 10-10 mol L-1, CuCl 
C)  4.8 × 10-5 mol L-1, CuCl 
D)  4.8 × 10-5 mol L-1, CuI 
E)  3.0 × 10-5 mol L-1, both CuCl and CuI are in the precipitate

Question 16

What happens at low pH to aluminum hydroxide precipitate?

Accepted Answer

A)  Al(H2O)63+ is formed and the Al(OH)3 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 forms.

Question 17

Define a buffer.

Accepted Answer

The answer of Define a buffer....

Question 18

A 1.0 L buffer solution is 0.250 mol L-1 CH3COOH and 0.050 mol L-1 CH3COOLi. Which of the following actions will exceed the capacity of the buffer?

Accepted Answer

A)  adding 0.050 moles of CH3COOLi 
B)  adding 0.050 moles of CH3COOH 
C)  adding 0.050 moles of HCl 
D)  adding 0.050 moles of NaCl 
E)  adding 0.050 moles of NH4Cl

Question 19

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 8.10?

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

Question 20

A solution contains 0.036 mol L-1 Cu2+ and 0.044 mol L-1 Fe2+. A solution containing sulfide ions is added to selectively precipitate one of the metal ions from solution. At what concentration of sulfide ion will a precipitate begin to form? What is the identity of the precipitate? Ksp(CuS) = 1.3 × 10-36, Ksp(FeS) = 6.3 × 10-18.

Accepted Answer

A)  1.4 × 10-16 mol L-1, FeS 
B)  3.6 × 10-35 mol L-1, CuS 
C)  3.6 × 10-35 mol L-1, FeS 
D)  1.4 × 10-16 mol L-1, CuS 
E)  1.4 × 10-16 mol L-1, both CuS and FeS will precipitate

Exam 16: Aqueous Ionic Equilibrium

A 25.0 mL sample of 0.150 mol L^-1 butanoic acid is titrated with a 0.150 mol L^-1 NaOH solution. What is the pH after 13.3 mL of base is added? The of butanoic acid is 1.5 × 10^-5.

Define buffer capacity.

Identify the expression for the solubility product constant for PbCl₂.

Describe the information necessary (and why) to choose a good indicator for a weak acid-strong base titration.

Which of the following is the correct equation relating Q to K_sp for a supersaturated solution?

For a strong acid titrated with a strong base, is the equivalence point acidic, basic, or neutral?

A 100.0 mL sample of 0.18 mol L^-1 HClO₄ is titrated with 0.27 mol L^-1 NaOH. Determine the pH of the solution after the addition of 66.67 mL of NaOH (this is the equivalence point) .

A 1.00 L buffer solution is 0.250 mol L^-1 in HF and 0.250 mol L^-1 in LiF. Calculate the pH of the solution after the addition of 0.150 moles of solid LiOH. Assume no volume change upon the addition of the base. The K_a for HF is 3.5 × 10^-4.

What is the pH at the equivalence point of a weak base-strong acid titration if 20.00 mL of NaOCl requires 28.30 mL of 0. 50 mol L^-1 HCl for complete neutralization? K_a = 3.0 × 10^-8 for HOCl.

The molar solubility of Ag₂S is 1.26 × 10^-16 mol L^-1 in pure water. Calculate the K_sp for Ag₂S.

A 25.0 mL sample of 0.150 mol L^-1acetic acid is titrated with a 0.150 mol L^-1 NaOH solution. What is the pH after 26.0 mL of base is added? The of acetic acid is 1.8 × 10^-5.

A 100.0 mL sample of 0.10 mol L^-1 NH₃ is titrated with 0.10 mol L^-1 HNO₃. Determine the pH of the solution after the addition of 200.0 mL of HNO₃. The K_b of NH₃ is 1.8 × 10^-5.

You wish to prepare a buffer containing CH₃COOH with a pH of 4.24. If the pK_a of acetic acid is 4.74, what ratio of [CH₃COO⁻]/[CH₃COOH] must you use?

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 2.34?

What happens at low pH to aluminum hydroxide precipitate?

Define a buffer.

A 1.0 L buffer solution is 0.250 mol L^-1 CH₃COOH and 0.050 mol L^-1 CH₃COOLi. Which of the following actions will exceed the capacity of the buffer?

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 8.10?

Exam 16: Aqueous Ionic Equilibrium

A 25.0 mL sample of 0.150 mol L-1 butanoic acid is titrated with a 0.150 mol L-1 NaOH solution. What is the pH after 13.3 mL of base is added? The of butanoic acid is 1.5 × 10-5.

Define buffer capacity.

Identify the expression for the solubility product constant for PbCl2.

Describe the information necessary (and why) to choose a good indicator for a weak acid-strong base titration.

Which of the following is the correct equation relating Q to Ksp for a supersaturated solution?

For a strong acid titrated with a strong base, is the equivalence point acidic, basic, or neutral?

A 100.0 mL sample of 0.18 mol L-1 HClO4 is titrated with 0.27 mol L-1 NaOH. Determine the pH of the solution after the addition of 66.67 mL of NaOH (this is the equivalence point) .

A 1.00 L buffer solution is 0.250 mol L-1 in HF and 0.250 mol L-1 in LiF. Calculate the pH of the solution after the addition of 0.150 moles of solid LiOH. Assume no volume change upon the addition of the base. The Ka for HF is 3.5 × 10-4.

What is the pH at the equivalence point of a weak base-strong acid titration if 20.00 mL of NaOCl requires 28.30 mL of 0. 50 mol L-1 HCl for complete neutralization? Ka = 3.0 × 10-8 for HOCl.

The molar solubility of Ag2S is 1.26 × 10-16 mol L-1 in pure water. Calculate the Ksp for Ag2S.

A 25.0 mL sample of 0.150 mol L-1 acetic acid is titrated with a 0.150 mol L-1 NaOH solution. What is the pH after 26.0 mL of base is added? The of acetic acid is 1.8 × 10-5.

A 100.0 mL sample of 0.10 mol L-1 NH3 is titrated with 0.10 mol L-1 HNO3. Determine the pH of the solution after the addition of 200.0 mL of HNO3. The Kb of NH3 is 1.8 × 10-5.

You wish to prepare a buffer containing CH3COOH with a pH of 4.24. If the pKa of acetic acid is 4.74, what ratio of [CH3COO⁻]/[CH3COOH] must you use?

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 2.34?

What happens at low pH to aluminum hydroxide precipitate?

Define a buffer.

A 1.0 L buffer solution is 0.250 mol L-1 CH3COOH and 0.050 mol L-1 CH3COOLi. Which of the following actions will exceed the capacity of the buffer?

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 8.10?

A 25.0 mL sample of 0.150 mol L^-1 butanoic acid is titrated with a 0.150 mol L^-1 NaOH solution. What is the pH after 13.3 mL of base is added? The of butanoic acid is 1.5 × 10^-5.

Identify the expression for the solubility product constant for PbCl₂.

Which of the following is the correct equation relating Q to K_sp for a supersaturated solution?

A 100.0 mL sample of 0.18 mol L^-1 HClO₄ is titrated with 0.27 mol L^-1 NaOH. Determine the pH of the solution after the addition of 66.67 mL of NaOH (this is the equivalence point) .

A 1.00 L buffer solution is 0.250 mol L^-1 in HF and 0.250 mol L^-1 in LiF. Calculate the pH of the solution after the addition of 0.150 moles of solid LiOH. Assume no volume change upon the addition of the base. The K_a for HF is 3.5 × 10^-4.

What is the pH at the equivalence point of a weak base-strong acid titration if 20.00 mL of NaOCl requires 28.30 mL of 0. 50 mol L^-1 HCl for complete neutralization? K_a = 3.0 × 10^-8 for HOCl.

The molar solubility of Ag₂S is 1.26 × 10^-16 mol L^-1 in pure water. Calculate the K_sp for Ag₂S.

A 25.0 mL sample of 0.150 mol L^-1acetic acid is titrated with a 0.150 mol L^-1 NaOH solution. What is the pH after 26.0 mL of base is added? The of acetic acid is 1.8 × 10^-5.

A 100.0 mL sample of 0.10 mol L^-1 NH₃ is titrated with 0.10 mol L^-1 HNO₃. Determine the pH of the solution after the addition of 200.0 mL of HNO₃. The K_b of NH₃ is 1.8 × 10^-5.

You wish to prepare a buffer containing CH₃COOH with a pH of 4.24. If the pK_a of acetic acid is 4.74, what ratio of [CH₃COO⁻]/[CH₃COOH] must you use?

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 2.34?

A 1.0 L buffer solution is 0.250 mol L^-1 CH₃COOH and 0.050 mol L^-1 CH₃COOLi. Which of the following actions will exceed the capacity of the buffer?

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 8.10?