Question 1

The concentration of Mg2+ in seawater is 5.0 * 10-2 M. What hydroxide concentration is needed to remove 90% of the Mg2+ by precipitation? (For Mg(OH)2, Ksp = 1.2 * 10-11.)

Accepted Answer

4.9 * 10<s...

Question 2

Assuming equal concentrations of conjugate base and acid, which one of the following mixtures is suitable for making a buffer solution with an optimum pH of 9.2-9.3?

Accepted Answer

A)  CH3COONa / CH3COOH (Ka = 1.8 * 10-5) 
B)  NH3 / NH4Cl (Ka = 5.6 * 10-10) 
C)  NaOCl / HOCl (Ka = 3.2 * 10-8) 
D)  NaNO2 / HNO2 (Ka = 4.5 * 10-4) 
E)  NaCl / HClF) None of the above
G) A) and E)

Question 3

How many moles of NaF must be dissolved in 1.00 liter of a saturated solution of PbF2 at 25°C to reduce the [Pb2+] to 1.0 * 10-6 M? The Ksp for PbF2 at 25 °C is 4.0 * 10-8.

Accepted Answer

The answer of How many moles of NaF must be...

Question 4

Calculate the equilibrium constant Kc for the net reaction shown below.
AgI(s)+ 2NH3(aq)  Ag(NH3)2+(aq)+ I-(aq)
For AgI, Ksp = 8.3 * 10-17; for Ag(NH3)2+, Kf = 1.5 * 107.

Accepted Answer

1.2 * 10<s...

Question 5

Calculate the equilibrium constant Kc for the following overall reaction:
AgCl(s)+ 2CN-(aq)  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 6

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)  8.40F) All of the above
G) B) and C)

Question 7

The solubility product for chromium(III) fluoride is Ksp = 6.6 * 10-11. What is the molar solubility of chromium(III) fluoride?

Accepted Answer

A)  1.6 * 10-3 M
B)  1.2 * 10-3 M
C)  6.6 * 10-11 M
D)  2.2 * 10-3 M
E)  1.6 * 10-6 MF) A) and B)
G) B) and E)

Question 8

Calculate the minimum concentration of Mg2+ that must be added to 0.10 M NaF in order to initiate a precipitate of magnesium fluoride. (For MgF2 , Ksp = 6.9 * 10-9.)

Accepted Answer

A)  1.4 * 107 M
B)  6.9 * 10-9 M
C)  6.9 * 10-8 M
D)  1.7 * 10-7 M
E)  6.9 * 10-7 MF) None of the above
G) A) and B)

Question 9

Will Fe(OH)3 precipitate from a buffer solution that is 0.60 M CH3COOH and 0.10 M CH3COONa, if the solution is also made to be 0.001 M in Fe3+? For Fe(OH)3, Ksp = 6.8 * 10-36.

Accepted Answer

The answer of Will Fe(OH)3 precipitate from a buffer solution...

Question 10

Describe how to prepare 500.mL of a cyanic acid (HCNO)/sodium cyanate (NaCNO)buffer having a pH of 4.80. [Ka(HCNO)= 2.0 * 10-4]

Accepted Answer

Dissolve amounts of the two compounds eq...

Question 11

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/LF) A) and D)
G) C) and D)

Question 12

At 25 °C, the base ionization constant for NH3 is 1.8 * 10-5. Determine the hydroxide ion concentration in a 0.150 M solution of ammonia at 25 °C.

Accepted Answer

1.6 * 10<s...

Question 13

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 14

Will a precipitate of magnesium fluoride form when 300.mL of 1.1 * 10-3 M MgCl2 are added to 500.mL of 1.2 * 10-3 M NaF? [Ksp (MgF2) = 6.9 * 10-9]

Accepted Answer

A)  Yes, Q > Ksp
B)  No, Q sp
C)  No, Q = Ksp
D)  Yes, Q spE) A) and B)
F) A) and C)

Question 15

Will a precipitate (ppt) form when 300.mL of 2.0 * 10-5 M AgNO3 are added to 200.mL of 2.5 * 10-9 M NaI? Answer yes or no, and identify the precipitate if there is one.

Accepted Answer

A)  Yes, the ppt is AgNO3(s) .
B)  Yes, the ppt is NaNO3(s) .
C)  Yes, the ppt is NaI(s) .
D)  Yes, the ppt is AgI(s) .
E)  No, a precipitate will not form.F) A) and D)
G) A) and E)

Question 16

At 25 °C, the base ionization constant for NH3 is 1.8 * 10-5. Determine the pH of a solution prepared by adding 0.0500 mol of solid ammonium chloride to 100.mL of 0.150 M ammonia.

Accepted Answer

The answer of At 25 °C, the base ionization constant...

Question 17

Calculate the concentration of chloride ions in a saturated lead(II) chloride (Ksp = 2.4 * 10-4) solution.

Accepted Answer

A)  2.4 * 10-4 M
B)  4.8 * 10-4 M
C)  3.9 * 10-2 M
D)  1.2 * 10-1 M
E)  7.8 * 10-2 MF) C) and D)
G) A) and E)

Question 18

Will a precipitate (ppt) form when 20.0 mL of 1.1 * 10-3 M Ba(NO3) 2 are added to 80.0 mL of 8.4 *10-4 M Na2CO3?

Accepted Answer

A)  Yes, the ppt is Ba(NO3 ) 2.
B)  Yes, the ppt is NaNO3.
C)  Yes, the ppt is BaCO3.
D)  Yes, the ppt is Na2CO3.
E)  No, a precipitate will not form.F) B) and C)
G) C) and D)

Question 19

The molar solubility of lead(II) iodate in water is 4.0 * 10-5 mol/L. Calculate Ksp for lead(II) iodate.

Accepted Answer

A)  1.6 * 10-9
B)  6.4 * 10-14
C)  2.6 * 10-13
D)  4.0 * 10-5
E)  4.0 * 10-15F) A) and B)
G) A) and E)

Question 20

Which of the following is the most acidic solution?

Accepted Answer

A)  0.10 M CH3COOH and 0.10 M CH3COONa
B)  0.10 M CH3COOH
C)  0.10 M HNO2
D)  0.10 M HNO2 and 0.10 M NaNO2
E)  0.10 M CH3COONaF) A) and E)
G) D) and E)

Exam 16: Acid-Base Equilibria and Solubility Equilibria

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]

Correct AnswerverifiedShow Answer

Will a precipitate (ppt) form when 20.0 mL of 1.1 * 10-3 M Ba(NO3) 2 are added to 80.0 mL of 8.4 *10-4 M Na2CO3?

Correct AnswerverifiedShow Answer

The solubility product for chromium(III) fluoride is Ksp = 6.6 * 10-11. What is the molar solubility of chromium(III) fluoride?

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

Correct AnswerverifiedShow Answer

Calculate the equilibrium constant Kc for the net reaction shown below. AgI(s)+ 2NH3(aq) Ag(NH3)2+(aq)+ I-(aq) For AgI, Ksp = 8.3 * 10-17; for Ag(NH3)2+, Kf = 1.5 * 107.

Correct Answerverified1.2 * 10View AnswerShow Answer

Describe how to prepare 500.mL of a cyanic acid (HCNO)/sodium cyanate (NaCNO)buffer having a pH of 4.80. [Ka(HCNO)= 2.0 * 10-4]

Correct AnswerverifiedDissolve amounts of the two compounds eq...View AnswerShow Answer

At 25 °C, the base ionization constant for NH3 is 1.8 * 10-5. Determine the hydroxide ion concentration in a 0.150 M solution of ammonia at 25 °C.

Correct Answerverified1.6 * 10View AnswerShow Answer

Calculate the minimum concentration of Mg2+ that must be added to 0.10 M NaF in order to initiate a precipitate of magnesium fluoride. (For MgF2 , Ksp = 6.9 * 10-9.)

Correct AnswerverifiedShow Answer

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

Correct Answerverified1.6 * 10View AnswerShow Answer

Calculate the concentration of chloride ions in a saturated lead(II) chloride (Ksp = 2.4 * 10-4) solution.

Correct AnswerverifiedShow Answer

The concentration of Mg2+ in seawater is 5.0 * 10-2 M. What hydroxide concentration is needed to remove 90% of the Mg2+ by precipitation? (For Mg(OH)2, Ksp = 1.2 * 10-11.)

Correct Answerverified4.9 * 10View AnswerShow Answer

Which of the following is the most acidic solution?

Correct AnswerverifiedShow Answer

Assuming equal concentrations of conjugate base and acid, which one of the following mixtures is suitable for making a buffer solution with an optimum pH of 9.2-9.3?

Correct AnswerverifiedShow Answer

Will Fe(OH)3 precipitate from a buffer solution that is 0.60 M CH3COOH and 0.10 M CH3COONa, if the solution is also made to be 0.001 M in Fe3+? For Fe(OH)3, Ksp = 6.8 * 10-36.

Correct AnswerverifiedShow Answer

Will a precipitate of magnesium fluoride form when 300.mL of 1.1 * 10-3 M MgCl2 are added to 500.mL of 1.2 * 10-3 M NaF? [Ksp (MgF2) = 6.9 * 10-9]

Correct AnswerverifiedShow Answer

How many moles of NaF must be dissolved in 1.00 liter of a saturated solution of PbF2 at 25°C to reduce the [Pb2+] to 1.0 * 10-6 M? The Ksp for PbF2 at 25 °C is 4.0 * 10-8.

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Will a precipitate (ppt) form when 300.mL of 2.0 * 10-5 M AgNO3 are added to 200.mL of 2.5 * 10-9 M NaI? Answer yes or no, and identify the precipitate if there is one.

Correct AnswerverifiedShow Answer

The molar solubility of lead(II) iodate in water is 4.0 * 10-5 mol/L. Calculate Ksp for lead(II) iodate.

Correct AnswerverifiedShow Answer

At 25 °C, the base ionization constant for NH3 is 1.8 * 10-5. Determine the pH of a solution prepared by adding 0.0500 mol of solid ammonium chloride to 100.mL of 0.150 M ammonia.

Correct AnswerverifiedShow Answer

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]

Correct Answer
verified

Will a precipitate (ppt) form when 20.0 mL of 1.1 * 10^-3 M Ba(NO₃) ₂ are added to 80.0 mL of 8.4 *10^-4 M Na₂CO₃?

Correct Answer
verified

The solubility product for chromium(III) fluoride is K_sp = 6.6 * 10^-11. What is the molar solubility of chromium(III) fluoride?

Correct Answer
verified

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

Correct Answer
verified

Calculate the equilibrium constant K_c for the net reaction shown below. AgI(s)+ 2NH₃(aq) Ag(NH₃)₂⁺(aq)+ I^-(aq) For AgI, K_sp = 8.3 * 10^-17; for Ag(NH₃)₂⁺, K_f = 1.5 * 10⁷.

Correct Answer
verified
1.2 * 10
View Answer

Describe how to prepare 500.mL of a cyanic acid (HCNO)/sodium cyanate (NaCNO)buffer having a pH of 4.80. [K_a(HCNO)= 2.0 * 10^-4]

Correct Answer
verified
Dissolve amounts of the two compounds eq...
View Answer

At 25 °C, the base ionization constant for NH₃ is 1.8 * 10^-5. Determine the hydroxide ion concentration in a 0.150 M solution of ammonia at 25 °C.

Correct Answer
verified
1.6 * 10
View Answer

Calculate the minimum concentration of Mg²⁺ that must be added to 0.10 M NaF in order to initiate a precipitate of magnesium fluoride. (For MgF₂ , K_sp = 6.9 * 10^-9.)

Correct Answer
verified

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

Correct Answer
verified
1.6 * 10
View Answer

Calculate the concentration of chloride ions in a saturated lead(II) chloride (K_sp = 2.4 * 10^-4) solution.

Correct Answer
verified

The concentration of Mg²⁺ in seawater is 5.0 * 10^-2M. What hydroxide concentration is needed to remove 90% of the Mg²⁺ by precipitation? (For Mg(OH)₂, K_sp = 1.2 * 10^-11.)

Correct Answer
verified
4.9 * 10
View Answer

Correct Answer
verified

Correct Answer
verified

Will Fe(OH)₃ precipitate from a buffer solution that is 0.60 M CH₃COOH and 0.10 M CH₃COONa, if the solution is also made to be 0.001 M in Fe³⁺? For Fe(OH)₃, K_sp = 6.8 * 10^-36.

Correct Answer
verified

Will a precipitate of magnesium fluoride form when 300.mL of 1.1 * 10^-3 M MgCl₂ are added to 500.mL of 1.2 * 10^-3 M NaF? [K_sp (MgF₂) = 6.9 * 10^-9]

Correct Answer
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How many moles of NaF must be dissolved in 1.00 liter of a saturated solution of PbF₂ at 25°C to reduce the [Pb²⁺] to 1.0 * 10^-6 M? The K_sp for PbF₂ at 25 °C is 4.0 * 10^-8.

Correct Answer
verified

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

Correct Answer
verified

Will a precipitate (ppt) form when 300.mL of 2.0 * 10^-5 M AgNO₃ are added to 200.mL of 2.5 * 10^-9 M NaI? Answer yes or no, and identify the precipitate if there is one.

Correct Answer
verified

The molar solubility of lead(II) iodate in water is 4.0 * 10^-5 mol/L. Calculate K_sp for lead(II) iodate.

Correct Answer
verified

At 25 °C, the base ionization constant for NH₃ is 1.8 * 10^-5. Determine the pH of a solution prepared by adding 0.0500 mol of solid ammonium chloride to 100.mL of 0.150 M ammonia.

Correct Answer
verified