Question 1

The Ksp for silver(I)phosphate is 1.8 * 10-18. Calculate the molar solubility of silver(I)phosphate.

Accepted Answer

A) 1.6 * 10-5 M 
B) 2.1 * 10-5 M 
C) 3.7 * 10-5 M 
D) 7.2 * 10-1 M 
E) 1.8 * 10-1 M 
A) 1.6 * 10-5 M 
B) 2.1 * 10-5 M 
C) 3.7 * 10-5 M 
D) 7.2 * 10-1 M 
E) 1.8 * 10-1 M

Question 2

The Ksp value for lead(II)chloride is 2.4 * 10-4. What is the molar solubility of lead(II)chloride?

Accepted Answer

A) 2.4 * 10-4 mol/L 
B) 6.2 * 10-2 mol/L 
C) 7.7 * 10-3 mol/L 
D) 3.9 * 10-2 mol/L 
E) 6.0 * 10-5 mol/L 
A) 2.4 * 10-4 mol/L 
B) 6.2 * 10-2 mol/L 
C) 7.7 * 10-3 mol/L 
D) 3.9 * 10-2 mol/L 
E) 6.0 * 10-5 mol/L

Question 3

Methyl red is a common acid-base indicator. It has a Ka equal to 6.3 * 10-6. Its un-ionized form is red and its anionic form is yellow. What color would a methyl red solution have at pH = 7.8?

Accepted Answer

A) green 
B) red 
C) blue 
D) yellow 
E) violet 
A) green 
B) red 
C) blue 
D) yellow 
E) violet

Question 4

A saturated sodium carbonate solution at 0°C contains 7.1 g of dissolved sodium carbonate per 100. mL of solution. The solubility product constant for sodium carbonate at this temperature is

Accepted Answer

A) 1.2. 
B) 0.30. 
C) 3.0 * 10-4. 
D) 0.90. 
E) 1.2 * 10-3. 
A) 1.2. 
B) 0.30. 
C) 3.0 * 10-4. 
D) 0.90. 
E) 1.2 * 10-3.

Question 5

To 1.00 L of a 0.100 M aqueous solution of the week base pyridine (C5H5N)is added 1.00 mL of 14.0 M NaOH. What fraction of the pyridine molecules in the resulting solution react with water to release hydroxide ions? [Kb(C5H5N)= 1.7 * 10-9]

Accepted Answer

A) 1.2 * 10-7 
B) 4.1 * 10-5 
C) 0.14 
D) 2.4 * 10-10 
E) 1.3 * 10-5 
A) 1.2 * 10-7 
B) 4.1 * 10-5 
C) 0.14 
D) 2.4 * 10-10 
E) 1.3 * 10-5

Question 6

What is the optimum pH of a sodium formate/formic acid buffer? (For formic acid, Ka = 1.7 * 10-4)

Accepted Answer

The answer of What is the optimum pH of a...

Question 7

The pH at the equivalence point of a titration may differ from 7.0 due to

Accepted Answer

A) the initial concentration of the standard solution. 
B) the indicator used. 
C) the self-ionization of H2O. 
D) the initial pH of the unknown. 
E) hydrolysis of the salt formed. 
A) the initial concentration of the standard solution. 
B) the indicator used. 
C) the self-ionization of H2O. 
D) the initial pH of the unknown. 
E) hydrolysis of the salt formed.

Question 8

Write a net ionic equation for the reaction that occurs when a small amount of hydrochloric acid is added to a buffer solution containing NH4Cl and NH3.

Accepted Answer

H<sup>+</sup> + NH<s

Question 9

The solubility of lead(II)iodide is 0.064 g/100 mL at 20oC. What is the solubility product for lead(II)iodide?

Accepted Answer

A) 1.1 * 10-8 
B) 3.9 * 10-6 
C) 1.1 * 10-11 
D) 2.7 * 10-12 
E) 1.4 * 10-3 
A) 1.1 * 10-8 
B) 3.9 * 10-6 
C) 1.1 * 10-11 
D) 2.7 * 10-12 
E) 1.4 * 10-3

Question 10

Bromothymol blue is a common acid-base indicator. It has a Ka equal to 1.6 * 10-7. Its un-ionized form is yellow and its conjugate base is blue. What color would a solution have at pH = 5.8?

Accepted Answer

The answer of Bromothymol blue is a common acid-base indicator....

Question 11

What volume of 0.0500 M sodium hydroxide should be added to 250. mL of 0.100 M HCOOH to obtain a solution with a pH of 4.50? [Ka(HCOOH)= 1.7 * 10-4]

Accepted Answer

A) 540 mL 
B) 420 mL 
C) 80. mL 
D) 340 mL 
E) 500. mL 
A) 540 mL 
B) 420 mL 
C) 80. mL 
D) 340 mL 
E) 500. mL

Question 12

Calculate the concentration of fluoride ions in a saturated barium fluoride (Ksp = 1.7 * 10-6)solution.

Accepted Answer

A) 7.6 * 10-3 M 
B) 1.5 * 10-2 M 
C) 3.4 * 10-5 M 
D) 1.7 * 10-6 M 
E) 3.4 * 10-6 M 
A) 7.6 * 10-3 M 
B) 1.5 * 10-2 M 
C) 3.4 * 10-5 M 
D) 1.7 * 10-6 M 
E) 3.4 * 10-6 M

Question 13

Calculate the pH of a solution that is 0.410 M in HOCl and 0.050 M in NaOCl. [Ka(HOCl)= 3.2 * 10-8]

Accepted Answer

A) 0.39 
B) 3.94 
C) 6.58 
D) 7.49 
E) 8.40 
A) 0.39 
B) 3.94 
C) 6.58 
D) 7.49 
E) 8.40

Question 14

An environmental chemist obtained a 200. mL sample of lake water believed to be contaminated with a single monoprotic strong acid. Titrating this sample with a 0.0050 M NaOH(aq)required 7.3 mL of the NaOH solution to reach the endpoint. If the size of the lake can be approximated as 1.1 km long by 2.3 km wide, and has an average depth of 10. m, estimate how many moles of the strong acid are present in the lake?

Accepted Answer

4.6 * 10<s

Question 15

Calculate the equilibrium constant Kc for the following overall reaction:
AgCl(s)+ 2CN-(aq) $\rarr$ Ag(CN)2-(aq)+ Cl-(aq)
For AgCl, Ksp = 1.6 * 10-10; for Ag(CN)2-, Kf = 1.0 * 1021.

Accepted Answer

1.6 * 10<s

Question 16

A titration of an acid and base to the equivalence point results in a noticeably acidic solution. It is likely this titration involves

Accepted Answer

A) a strong acid and a weak base. 
B) a weak acid and a strong base. 
C) a weak acid and a weak base (where Ka equals Kb). 
D) a strong acid and a strong base. 
A) a strong acid and a weak base. 
B) a weak acid and a strong base. 
C) a weak acid and a weak base (where Ka equals Kb). 
D) a strong acid and a strong base.

Question 17

What is the effective pH range for a sodium acetate/acetic acid buffer? (For CH3COOH, Ka= 1.8 * 10-5)

Accepted Answer

The answer of What is the effective pH range for...

Question 18

Over what range of pH is a HOCl - NaOCl buffer effective?

Accepted Answer

A) pH 2.0 - pH 4.0 
B) pH 7.5 - pH 9.5 
C) pH 6.5 - pH 8.5 
D) pH 6.5 - pH 9.5 
E) pH 1.0 - pH 14.0 
A) pH 2.0 - pH 4.0 
B) pH 7.5 - pH 9.5 
C) pH 6.5 - pH 8.5 
D) pH 6.5 - pH 9.5 
E) pH 1.0 - pH 14.0

Question 19

Calculate the pH of a buffer solution that contains 0.25 M benzoic acid (C6H5CO2H)and 0.15M sodium benzoate (C6H5COONa). [Ka = 6.5 * 10-5 for benzoic acid]

Accepted Answer

A) 3.97 
B) 4.83 
C) 4.19 
D) 3.40 
E) 4.41 
A) 3.97 
B) 4.83 
C) 4.19 
D) 3.40 
E) 4.41

Question 20

Will a precipitate form (yes or no)when 50.0 mL of 1.2 * 10-3 M Pb(NO3)2 are added to 50.0 mL of 2.0 * 10-4 M Na2S? If so, identify the precipitate.

Accepted Answer

A) Yes, the precipitate is PbS. 
B) Yes, the precipitate is NaNO3. 
C) Yes, the precipitate is Na2S. 
D) Yes, the precipitate is Pb(NO3)2. 
E) No, a precipitate will not form. 
A) Yes, the precipitate is PbS. 
B) Yes, the precipitate is NaNO3. 
C) Yes, the precipitate is Na2S. 
D) Yes, the precipitate is Pb(NO3)2. 
E) No, a precipitate will not form.

Exam 17: Acid-Base Equilibria and Solubility Equilibria

The Ksp for silver(I)phosphate is 1.8 * 10-18. Calculate the molar solubility of silver(I)phosphate.

The Ksp value for lead(II)chloride is 2.4 * 10-4. What is the molar solubility of lead(II)chloride?

Methyl red is a common acid-base indicator. It has a Ka equal to 6.3 * 10-6. Its un-ionized form is red and its anionic form is yellow. What color would a methyl red solution have at pH = 7.8?

A saturated sodium carbonate solution at 0°C contains 7.1 g of dissolved sodium carbonate per 100. mL of solution. The solubility product constant for sodium carbonate at this temperature is

To 1.00 L of a 0.100 M aqueous solution of the week base pyridine (C5H5N)is added 1.00 mL of 14.0 M NaOH. What fraction of the pyridine molecules in the resulting solution react with water to release hydroxide ions? [Kb(C5H5N)= 1.7 * 10-9]

What is the optimum pH of a sodium formate/formic acid buffer? (For formic acid, Ka = 1.7 * 10-4)

The pH at the equivalence point of a titration may differ from 7.0 due to

Write a net ionic equation for the reaction that occurs when a small amount of hydrochloric acid is added to a buffer solution containing NH4Cl and NH3.

The solubility of lead(II)iodide is 0.064 g/100 mL at 20oC. What is the solubility product for lead(II)iodide?

Bromothymol blue is a common acid-base indicator. It has a Ka equal to 1.6 * 10-7. Its un-ionized form is yellow and its conjugate base is blue. What color would a solution have at pH = 5.8?

What volume of 0.0500 M sodium hydroxide should be added to 250. mL of 0.100 M HCOOH to obtain a solution with a pH of 4.50? [Ka(HCOOH)= 1.7 * 10-4]

Calculate the concentration of fluoride ions in a saturated barium fluoride (Ksp = 1.7 * 10-6)solution.

Calculate the pH of a solution that is 0.410 M in HOCl and 0.050 M in NaOCl. [Ka(HOCl)= 3.2 * 10-8]

Calculate the equilibrium constant Kc for the following overall reaction: AgCl(s)+ 2CN-(aq) →\rarr→ Ag(CN)2-(aq)+ Cl-(aq) For AgCl, Ksp = 1.6 * 10-10; for Ag(CN)2-, Kf = 1.0 * 1021.

A titration of an acid and base to the equivalence point results in a noticeably acidic solution. It is likely this titration involves

What is the effective pH range for a sodium acetate/acetic acid buffer? (For CH3COOH, Ka= 1.8 * 10-5)

Over what range of pH is a HOCl - NaOCl buffer effective?

Calculate the pH of a buffer solution that contains 0.25 M benzoic acid (C6H5CO2H)and 0.15M sodium benzoate (C6H5COONa). [Ka = 6.5 * 10-5 for benzoic acid]

Will a precipitate form (yes or no)when 50.0 mL of 1.2 * 10-3 M Pb(NO3)2 are added to 50.0 mL of 2.0 * 10-4 M Na2S? If so, identify the precipitate.

Introduction

Atoms, Molecules, and Ions

Stoichiometry

Reactions in Aqueous Solution

Gases

Energy Relationships in Chemical Reactions

The Electronic Structure of Atoms

The Periodic Table

Chemical Bonding I: the Covalent Bond

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Introduction to Organic Chemistry

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Thermodynamics

Redox Reactions and Electrochemistry

The Chemistry of Coordination Compounds

Nuclear Chemistry

Organic Polymerssynthetic and Natural

Filters

The K_sp for silver(I)phosphate is 1.8 * 10^-18. Calculate the molar solubility of silver(I)phosphate.

The K_sp value for lead(II)chloride is 2.4 * 10^-4. What is the molar solubility of lead(II)chloride?

Methyl red is a common acid-base indicator. It has a K_a equal to 6.3 * 10^-6. Its un-ionized form is red and its anionic form is yellow. What color would a methyl red solution have at pH = 7.8?

To 1.00 L of a 0.100 M aqueous solution of the week base pyridine (C₅H₅N)is added 1.00 mL of 14.0 M NaOH. What fraction of the pyridine molecules in the resulting solution react with water to release hydroxide ions? [K_b(C₅H₅N)= 1.7 * 10^-9]

What is the optimum pH of a sodium formate/formic acid buffer? (For formic acid, K_a = 1.7 * 10^-4)

Write a net ionic equation for the reaction that occurs when a small amount of hydrochloric acid is added to a buffer solution containing NH₄Cl and NH₃.

The solubility of lead(II)iodide is 0.064 g/100 mL at 20^oC. What is the solubility product for lead(II)iodide?

Bromothymol blue is a common acid-base indicator. It has a K_a equal to 1.6 * 10^-7. Its un-ionized form is yellow and its conjugate base is blue. What color would a solution have at pH = 5.8?

What volume of 0.0500 M sodium hydroxide should be added to 250. mL of 0.100 M HCOOH to obtain a solution with a pH of 4.50? [K_a(HCOOH)= 1.7 * 10^-4]

Calculate the concentration of fluoride ions in a saturated barium fluoride (K_sp = 1.7 * 10^-6)solution.

Calculate the pH of a solution that is 0.410 M in HOCl and 0.050 M in NaOCl. [K_a(HOCl)= 3.2 * 10^-8]

Calculate the equilibrium constant K_c for the following overall reaction: AgCl(s)+ 2CN^-(aq) $\rarr$ Ag(CN)₂^-(aq)+ Cl^-(aq) For AgCl, K_sp = 1.6 * 10^-10; for Ag(CN)₂^-, K_f = 1.0 * 10²¹.

What is the effective pH range for a sodium acetate/acetic acid buffer? (For CH₃COOH, K_a= 1.8 * 10^-5)

Calculate the pH of a buffer solution that contains 0.25 M benzoic acid (C₆H₅CO₂H)and 0.15M sodium benzoate (C₆H₅COONa). [K_a = 6.5 * 10^-5 for benzoic acid]

Will a precipitate form (yes or no)when 50.0 mL of 1.2 * 10^-3 M Pb(NO₃)₂ are added to 50.0 mL of 2.0 * 10^-4 M Na₂S? If so, identify the precipitate.