Question 1

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)  None of the above are true. 
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)  None of the above are true.

Question 2

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

Accepted Answer

A)  PbSO4, Ksp = 1.82 × 10-8 
B)  MgCO3, Ksp = 6.82 × 10-6 
C)  AgCl, Ksp = 1.77 × 10-10 
D)  PbS, Ksp = 9.04 × 10-29 
E)  HgS, Ksp = 1.60 × 10-54 
A)  PbSO4, Ksp = 1.82 × 10-8 
B)  MgCO3, Ksp = 6.82 × 10-6 
C)  AgCl, Ksp = 1.77 × 10-10 
D)  PbS, Ksp = 9.04 × 10-29 
E)  HgS, Ksp = 1.60 × 10-54

Question 3

Identify the compound that is base-insoluble.

Accepted Answer

A)  PbCl2 
B)  Sb2S3 
C)  NiS 
D)  Ca3(PO4)2 
E)  KCl 
A)  PbCl2 
B)  Sb2S3 
C)  NiS 
D)  Ca3(PO4)2 
E)  KCl

Question 4

What is the pH of the resulting solution if 45.00 mL of 0.10 M acetic acid is added to 10.00 mL of 0.10 M NaOH? Assume that the volumes of the solutions are additive.Ka = 1.8 × 10-5 for CH3CO2H.

Accepted Answer

A)  9.80 
B)  8.71 
C)  5.29 
D)  4.20 
A)  9.80 
B)  8.71 
C)  5.29 
D)  4.20

Question 5

What is the pH of the resulting solution if 35 mL of 0.432 M methylamine,CH3NH2,is added to 15 mL of 0.234 M HCl? Assume that the volumes of the solutions are additive.Ka = 2.70 × 10-11 for CH3NH3+.

Accepted Answer

A)  2.91 
B)  3.95 
C)  10.05 
D)  11.09 
A)  2.91 
B)  3.95 
C)  10.05 
D)  11.09

Question 6

Identify the indicator that has two endpoints.

Accepted Answer

A)  phenol red 
B)  alizarin 
C)  m-nitrophenol 
D)  phenolphthalein 
E)  alizarin yellow R 
A)  phenol red 
B)  alizarin 
C)  m-nitrophenol 
D)  phenolphthalein 
E)  alizarin yellow R

Question 7

The molar solubility of ZnS is 1.6 × 10-12 M in pure water.Calculate the Ksp for ZnS.

Accepted Answer

A)  8.0 × 10-13 
B)  3.2 × 10-12 
C)  1.6 × 10-35 
D)  2.6 × 10-24 
E)  6.80 × 10-5 
A)  8.0 × 10-13 
B)  3.2 × 10-12 
C)  1.6 × 10-35 
D)  2.6 × 10-24 
E)  6.80 × 10-5

Question 8

A 100.0 mL sample of 0.180 M HClO4 is titrated with 0.270 M LiOH.Determine the pH of the solution after the addition of 75.0 mL of LiOH.

Accepted Answer

A)  12.1 
B)  2.65 
C)  11.35 
D)  1.89 
E)  13.06 
A)  12.1 
B)  2.65 
C)  11.35 
D)  1.89 
E)  13.06

Question 9

What is the pH of a buffer system prepared by dissolving 10.70 grams of NH4Cl and 35.00 mL of 12 M NH3 in enough water to make 1.000 L of solution? Kb = 1.80 × 10-5 for NH3.

Accepted Answer

A)  8.93 
B)  9.26 
C)  9.58 
D)  11.32 
A)  8.93 
B)  9.26 
C)  9.58 
D)  11.32

Question 10

Which of the following acids (listed with Ka values)and their conjugate base would form a buffer with a pH of 2.34?

Accepted Answer

A)  C6H5COOH, Ka = 6.5 × 10-5 
B)  HN3, Ka = 2.5 × 10-5 
C)  HClO, Ka = 2.9 × 10-8 
D)  HF, Ka = 3.5 × 10-4 
E)  HClO2, Ka = 1.1 × 10-2 
A)  C6H5COOH, Ka = 6.5 × 10-5 
B)  HN3, Ka = 2.5 × 10-5 
C)  HClO, Ka = 2.9 × 10-8 
D)  HF, Ka = 3.5 × 10-4 
E)  HClO2, Ka = 1.1 × 10-2

Question 11

A solution is prepared by dissolving 0.23 mol of butanoic acid and 0.27 mol of sodium butanoate in water sufficient to yield 1.00 L of solution.The addition of 0.05 mol of HCl to this buffer solution causes the pH to drop slightly.The pH does not decrease drastically because the HCl reacts with the ________ present in the buffer solution.The Ka of butanoic acid is 1.36 × 10-3.

Accepted Answer

A)  H2O 
B)  H3O+ 
C)  butanoate ion 
D)  butanoic acid 
E)  This is a buffer solution: the pH does not change upon addition of acid or base. 
A)  H2O 
B)  H3O+ 
C)  butanoate ion 
D)  butanoic acid 
E)  This is a buffer solution: the pH does not change upon addition of acid or base.

Question 12

Calculate the pH of a buffer that is 0.080 M HF and 0.040 M NaF.The Ka for HF is 3.5 × 10-4.

Accepted Answer

A)  2.06 
B)  4.86 
C)  3.16 
D)  3.56 
E)  3.76 
A)  2.06 
B)  4.86 
C)  3.16 
D)  3.56 
E)  3.76

Question 13

Calculate the pH of a buffer that is 0.225 M HC2H3O2 and 0.162 M KC2H3O2.The Ka for HC2H3O2 is 1.8 × 10-5.

Accepted Answer

A)  4.89 
B)  9.11 
C)  4.74 
D)  9.26 
E)  4.60 
A)  4.89 
B)  9.11 
C)  4.74 
D)  9.26 
E)  4.60

Question 14

A solution containing AgNO3 is mixed with a solution of NaCl to form a solution that is 0.10 M in AgNO3 and 0.075 M in NaCl.What will happen once these solutions are mixed? Ksp (AgCl)= 1.77 × 10-10.

Accepted Answer

A)  Nothing will happen since the molar solubility of AgCl is higher than the solution concentrations. 
B)  Silver chloride will precipitate out of solution, leaving an unsaturated solution of AgCl. 
C)  Silver chloride will precipitate out of solution, leaving a saturated AgCl solution. 
D)  Nothing will happen since NaCl and AgNO3 are both soluble compounds. 
E)  There is not enough information to say anything about this solution. 
A)  Nothing will happen since the molar solubility of AgCl is higher than the solution concentrations. 
B)  Silver chloride will precipitate out of solution, leaving an unsaturated solution of AgCl. 
C)  Silver chloride will precipitate out of solution, leaving a saturated AgCl solution. 
D)  Nothing will happen since NaCl and AgNO3 are both soluble compounds. 
E)  There is not enough information to say anything about this solution.

Question 15

If the pKa of HCHO2 is 3.74 and the pH of an HCHO2/NaCHO2 solution is 3.74,which of the following is TRUE?

Accepted Answer

A)  [HCHO2] > [NaCHO2] 
B)  [HCHO2] = [NaCHO2] 
C)  [HCHO2] 2] 
D)  [HCHO2] 2] 
E)  It is not possible to make a buffer of this pH from HCHO2 and NaCHO2. 
A)  [HCHO2] > [NaCHO2] 
B)  [HCHO2] = [NaCHO2] 
C)  [HCHO2] 2] 
D)  [HCHO2] 2] 
E)  It is not possible to make a buffer of this pH from HCHO2 and NaCHO2.

Question 16

A ligand is a molecule or ion that acts as a

Accepted Answer

A)  Lewis acid 
B)  Brønsted-Lowry acid 
C)  Arrhenius base 
D)  Lewis base 
E)  conjugate base 
A)  Lewis acid 
B)  Brønsted-Lowry acid 
C)  Arrhenius base 
D)  Lewis base 
E)  conjugate base

Question 17

Give the expression for the solubility product constant for Ca3(PO4)2.

Accepted Answer

A)    
B)    
C)    
D)  [ Ca2+]2[ PO43-]3 
E)  [Ca2+]3[PO43-]2 
A)    
B)    
C)    
D)  [ Ca2+]2[ PO43-]3 
E)  [Ca2+]3[PO43-]2

Question 18

A solution contains 2.2 × 10-3 M in Cu2+ and 0.33 M in LiCN.If the Kf for Cu(CN)42- is 1.0 × 1025,how much copper ion remains at equilibrium?

Accepted Answer

A)  3.8 × 10-24 M 
B)  1.9 × 10-26 M 
C)  6.7 × 10-28 M 
D)  2.9 × 10-27 M 
E)  4.6 × 10-25 M 
A)  3.8 × 10-24 M 
B)  1.9 × 10-26 M 
C)  6.7 × 10-28 M 
D)  2.9 × 10-27 M 
E)  4.6 × 10-25 M

Question 19

What is the Ksp of Cu(OH)2 if the molar solubility at 25°C is 3.42x10-7 M?

Accepted Answer

A)  3.3 × 10-12 
B)  4.2 × 10-13 
C)  1.6 × 10-19 
D)  1.3 × 10-4 
A)  3.3 × 10-12 
B)  4.2 × 10-13 
C)  1.6 × 10-19 
D)  1.3 × 10-4

Question 20

A 100.0 mL sample of 0.18 M HClO4 is titrated with 0.27 M LiOH.Determine the pH of the solution after the addition of 30.0 mL of LiOH.

Accepted Answer

A)  0.86 
B)  1.21 
C)  2.00 
D)  1.12 
E)  2.86 
A)  0.86 
B)  1.21 
C)  2.00 
D)  1.12 
E)  2.86

Exam 18: Aqueous Ionic Equilibrium

Which of the following is TRUE?

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

Identify the compound that is base-insoluble.

What is the pH of the resulting solution if 45.00 mL of 0.10 M acetic acid is added to 10.00 mL of 0.10 M NaOH? Assume that the volumes of the solutions are additive.Ka = 1.8 × 10-5 for CH3CO2H.

What is the pH of the resulting solution if 35 mL of 0.432 M methylamine,CH3NH2,is added to 15 mL of 0.234 M HCl? Assume that the volumes of the solutions are additive.Ka = 2.70 × 10-11 for CH3NH3+.

Identify the indicator that has two endpoints.

The molar solubility of ZnS is 1.6 × 10-12 M in pure water.Calculate the Ksp for ZnS.

A 100.0 mL sample of 0.180 M HClO4 is titrated with 0.270 M LiOH.Determine the pH of the solution after the addition of 75.0 mL of LiOH.

What is the pH of a buffer system prepared by dissolving 10.70 grams of NH4Cl and 35.00 mL of 12 M NH3 in enough water to make 1.000 L of solution? Kb = 1.80 × 10-5 for NH3.

Which of the following acids (listed with Ka values)and their conjugate base would form a buffer with a pH of 2.34?

Calculate the pH of a buffer that is 0.080 M HF and 0.040 M NaF.The Ka for HF is 3.5 × 10-4.

Calculate the pH of a buffer that is 0.225 M HC2H3O2 and 0.162 M KC2H3O2.The Ka for HC2H3O2 is 1.8 × 10-5.

A solution containing AgNO3 is mixed with a solution of NaCl to form a solution that is 0.10 M in AgNO3 and 0.075 M in NaCl.What will happen once these solutions are mixed? Ksp (AgCl)= 1.77 × 10-10.

If the pKa of HCHO2 is 3.74 and the pH of an HCHO2/NaCHO2 solution is 3.74,which of the following is TRUE?

A ligand is a molecule or ion that acts as a

Give the expression for the solubility product constant for Ca3(PO4)2.

A solution contains 2.2 × 10-3 M in Cu2+ and 0.33 M in LiCN.If the Kf for Cu(CN)42- is 1.0 × 1025,how much copper ion remains at equilibrium?

What is the Ksp of Cu(OH)2 if the molar solubility at 25°C is 3.42x10-7 M?

A 100.0 mL sample of 0.18 M HClO4 is titrated with 0.27 M LiOH.Determine the pH of the solution after the addition of 30.0 mL of LiOH.

Essentials: Units, Measurements, and Problem Solving

Atoms

The Quantum Mechanical Model of the Atom

Periodic Properties of the Elements

Molecules and Compounds

Chemical Bonding I

Chemical Bonding Ii

Chemical Reactions and Chemical Quantities

Introduction to Solutions and Aqueous Reactions

Thermochemistry

Gases

Liquids, Solids, and Intermolecular Forces

Crystalline Solids and Modern Materials

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Free Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry

Transition Metals and Coordination Compounds

Filters

What is the pH of the resulting solution if 45.00 mL of 0.10 M acetic acid is added to 10.00 mL of 0.10 M NaOH? Assume that the volumes of the solutions are additive.K_a = 1.8 × 10^-5for CH₃CO₂H.

What is the pH of the resulting solution if 35 mL of 0.432 M methylamine,CH₃NH₂,is added to 15 mL of 0.234 M HCl? Assume that the volumes of the solutions are additive.K_a = 2.70 × 10^-11for CH₃NH₃⁺.

The molar solubility of ZnS is 1.6 × 10^-12 M in pure water.Calculate the K_sp for ZnS.

A 100.0 mL sample of 0.180 M HClO₄ is titrated with 0.270 M LiOH.Determine the pH of the solution after the addition of 75.0 mL of LiOH.

What is the pH of a buffer system prepared by dissolving 10.70 grams of NH₄Cl and 35.00 mL of 12 M NH₃ in enough water to make 1.000 L of solution? K_b = 1.80 × 10^-5for NH₃.

Which of the following acids (listed with K_a values)and their conjugate base would form a buffer with a pH of 2.34?

Calculate the pH of a buffer that is 0.080 M HF and 0.040 M NaF.The K_a for HF is 3.5 × 10^-4.

Calculate the pH of a buffer that is 0.225 M HC₂H₃O₂ and 0.162 M KC₂H₃O₂.The K_a for HC₂H₃O₂ is 1.8 × 10^-5.

A solution containing AgNO₃ is mixed with a solution of NaCl to form a solution that is 0.10 M in AgNO₃ and 0.075 M in NaCl.What will happen once these solutions are mixed? K_sp (AgCl)= 1.77 × 10^-10.

If the pKa of HCHO₂ is 3.74 and the pH of an HCHO₂/NaCHO₂solution is 3.74,which of the following is TRUE?

Give the expression for the solubility product constant for Ca₃(PO₄)₂.

A solution contains 2.2 × 10^-3M in Cu²⁺ and 0.33 M in LiCN.If the K_f for Cu(CN)₄^2- is 1.0 × 10²⁵,how much copper ion remains at equilibrium?

What is the K_sp of Cu(OH)₂ if the molar solubility at 25°C is 3.42x10^-7 M?

A 100.0 mL sample of 0.18 M HClO₄ is titrated with 0.27 M LiOH.Determine the pH of the solution after the addition of 30.0 mL of LiOH.