Question 1

Which,if any,of the following aqueous mixtures would be a buffer system?

Accepted Answer

A)  CH3COOH,NaH2PO4
B)  H2CO3,HCO3-
C)  H2PO4-,HCO3-
D)  HSO4-,HSO3-
E)  None of these will be a buffer solution.F) B) and C)
G) A) and C)

Question 2

A 20.0-mL sample of 0.25 M HNO3 is titrated with 0.15 M Na OH.What is the pH of the solution after 30.0 mL of NaOH have been added to the acid?

Accepted Answer

A)  2.00
B)  1.60
C)  1.05
D)  1.00
E)  None of these choices is correct.F) C) and E)
G) A) and D)

Question 3

A solution is prepared by adding 100 mL of 0.2 M hydrochloric acid to 100 mL of 0.4 M sodium formate.Is this a buffer solution,and if so,what is its pH?

Accepted Answer

A)  It is a buffer,pH > pKa of formic acid.
B)  It is a buffer,pH a of formic acid.
C)  It is a buffer,pH = pKa of formic acid.
D)  It is a buffer,pH = pKb of sodium formate.
E)  Since hydrochloric acid is a strong acid,this is not a buffer.F) D) and E)
G) All of the above

Question 4

A buffer is prepared by adding 0.5 mol of solid sodium hydroxide to 1.0 L of 1.0 M acetic acid (CH3COOH) .What is the pH of the buffer?

Accepted Answer

A)  The pH will be pKa - 0.30,where pKa is that of acetic acid.
B)  The pH will be greater than the pKa for acetic acid.
C)  The pH will be less than the value in answer a.
D)  The pH will be equal to the pKa for acetic acid.
E)  More information is needed to solve the problem.F) None of the above
G) C) and E)

Question 5

Calculate the solubility of copper(II)carbonate,CuCO3,in 1.00 mol L-1 NH3.Ksp = 3.0 $\times$ 10-12 for CuCO3,Kf = 5.6 $\times$ 1011 for Cu(NH3)42+

Accepted Answer

0.16 mol L...

Question 6

Citric acid has an acid dissociation constant of 8.4  ×	imes×  10-4.It would be most effective for preparation of a buffer with a pH of

Accepted Answer

A)  2
B)  3
C)  4
D)  5
E)  6 F) B) and C)
G) A) and E)

Question 7

A 10.0-mL sample of 0.75 M CH3CH2COOH is titrated with 0.30 M NaOH.What is the pH of the solution after 22.0 mL of NaOH have been added to the acid?
Ka = 1.3  ×	imes×  10-5

Accepted Answer

A)  5.75
B)  4.94
C)  4.83
D)  4.02
E)  3.95 F) A) and C)
G) A) and E)

Question 8

A buffer is to be prepared by adding solid sodium acetate to 0.10 M CH3COOH.Which of the following concentrations of sodium acetate will produce the most effective buffer?

Accepted Answer

A)  3.0 M CH3COONa
B)  2.5 M CH3COONa
C)  2.0 M CH3COONa
D)  1.5 M CH3COONa
E)  0.30 M CH3COONaF) A) and B)
G) A) and C)

Question 9

The solubility of calcium chromate is 1.56  ×	imes×  10-3 g/100 mL of solution.What is the Ksp for CaCrO4?

Accepted Answer

A)  2.4  ×	imes×  10-4
B)  1.5  ×	imes×  10-5
C)  7.6  ×	imes×  10-6
D)  1.0  ×	imes×  10-8
E)  ×	imes×  10-8 F) A) and E)
G) A) and C)

Question 10

The indicator propyl red has Ka = 3.3  ×	imes×  10-6.What would be the approximate pH range over which it would change color?

Accepted Answer

A)  3.5-5.5
B)  4.5-6.5
C)  5.5-7.5
D)  6.5-8.5
E)  None of these choices is correct. F) A) and E)
G) A) and D)

Question 11

A 25.0-mL sample of 1.00 M NH3 is titrated with 0.15 M HCl.What is the pH of the solution after 15.00 mL of acid have been added to the ammonia solution? Kb = 1.8  ×	imes×  10-5

Accepted Answer

A)  10.26
B)  9.30
C)  9.21
D)  8.30
E)  8.21 F) D) and E)
G) A) and E)

Question 12

Calculate the solubility of magnesium sulfate,MgSO4,when placed into a 0.10 M MgCl2 solution.
Ksp = 5.9  ×	imes×  10-3

Accepted Answer

A)  4.2  ×	imes×  10-2 M
B)  5.9  ×	imes×  10-2 M
C)  7.7  ×	imes×  10-2 M
D)  3.5  ×	imes×  10-5 M
E)  3.5  ×	imes×  10-6 M F) A) and E)
G) B) and D)

Question 13

An acetic acid buffer containing 0.50 M CH3COOH and 0.50 M CH3COONa has a pH of 4.74.What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer?

Accepted Answer

A)  4.77
B)  4.71
C)  4.68
D)  4.62
E)  None of these choices is correct.F) A) and D)
G) C) and D)

Question 14

A 20.0-mL sample of 0.30 M HBr is titrated with 0.15 M NaOH.What is the pH of the solution after 40.3 mL of NaOH have been added to the acid?

Accepted Answer

A)  2.95
B)  3.13
C)  10.87
D)  11.05
E)  13.14F) A) and D)
G) A) and E)

Question 15

When a strong acid is titrated with a weak base,the pH at the equivalence point

Accepted Answer

A)  is greater than 7.0.
B)  is equal to 7.0.
C)  is less than 7.0.
D)  is equal to the pKa of the acid.
E)  is equal to the pKb of the base.F) B) and E)
G) A) and B)

Question 16

Calculate the solubility of silver chromate,Ag2CrO4,in 0.005 M Na2CrO4.Ksp = 2.6  ×	imes×  10-12

Accepted Answer

A)  1.4  ×	imes×  10-4 M
B)  3.4  ×	imes×  10-5 M
C)  1.1  ×	imes×  10-5 M
D)  1.6  ×	imes×  10-6 M
E)  ×	imes×  10-6 M F) A) and E)
G) A) and C)

Question 17

Fe(NO3)3 (0.00100 mol)and KSCN (0.200 mol)are added to water to make exactly 1 liter of solution.The red complex ion FeSCN2+ is produced.Calculate the concentrations of Fe3+(aq)and FeSCN2+(aq)at equilibrium,if Kf of the FeSCN2+ is 8.9 $\times$ 102.

Accepted Answer

[Fe³⁺] = 5.6

10

Question 18

If the pH of a buffer solution is greater than the pKa value of the buffer acid,the buffer will have more capacity to neutralize added base than added acid.

Accepted Answer

A) True 
 B)False

Question 19

A change in pH will significantly affect the solubility of which,if any,of the following compounds?

Accepted Answer

A)  BaF2
B)  CuCl
C)  CuBr
D)  AgI
E)  None of the solubilities will be significantly affected.F) A) and D)
G) A) and C)

Question 20

A 50.0-mL sample of 0.50 M HCl is titrated with 0.50 M NaOH.What is the pH of the solution after 28.0 mL of NaOH have been added to the acid?

Accepted Answer

A)  0.85
B)  0.75
C)  0.66
D)  0.49
E)  3.8F) A) and C)
G) C) and E)

Exam 19: Ionic Equilibria in Aqueous Systems

A 50.0-mL sample of 0.50 M HCl is titrated with 0.50 M NaOH.What is the pH of the solution after 28.0 mL of NaOH have been added to the acid?

Correct AnswerverifiedShow Answer

Calculate the solubility of copper(II)carbonate,CuCO3,in 1.00 mol L-1 NH3.Ksp = 3.0 ×\times× 10-12 for CuCO3,Kf = 5.6 ×\times× 1011 for Cu(NH3)42+

Correct Answerverified0.16 mol L...View AnswerShow Answer

When a strong acid is titrated with a weak base,the pH at the equivalence point

Correct AnswerverifiedShow Answer

If the pH of a buffer solution is greater than the pKa value of the buffer acid,the buffer will have more capacity to neutralize added base than added acid.

Correct AnswerverifiedShow Answer

The solubility of calcium chromate is 1.56 ×\times× 10-3 g/100 mL of solution.What is the Ksp for CaCrO4?

Correct AnswerverifiedShow Answer

A buffer is prepared by adding 0.5 mol of solid sodium hydroxide to 1.0 L of 1.0 M acetic acid (CH3COOH) .What is the pH of the buffer?

Correct AnswerverifiedShow Answer

A 20.0-mL sample of 0.30 M HBr is titrated with 0.15 M NaOH.What is the pH of the solution after 40.3 mL of NaOH have been added to the acid?

Correct AnswerverifiedShow Answer

A 20.0-mL sample of 0.25 M HNO3 is titrated with 0.15 M Na OH.What is the pH of the solution after 30.0 mL of NaOH have been added to the acid?

Correct AnswerverifiedShow Answer

Fe(NO3)3 (0.00100 mol)and KSCN (0.200 mol)are added to water to make exactly 1 liter of solution.The red complex ion FeSCN2+ is produced.Calculate the concentrations of Fe3+(aq)and FeSCN2+(aq)at equilibrium,if Kf of the FeSCN2+ is 8.9 ×\times× 102.

Correct Answerverified[Fe3+] = 5.6 10View AnswerShow Answer

A change in pH will significantly affect the solubility of which,if any,of the following compounds?

Correct AnswerverifiedShow Answer

Citric acid has an acid dissociation constant of 8.4 ×\times× 10-4.It would be most effective for preparation of a buffer with a pH of

Correct AnswerverifiedShow Answer

Calculate the solubility of silver chromate,Ag2CrO4,in 0.005 M Na2CrO4.Ksp = 2.6 ×\times× 10-12

Correct AnswerverifiedShow Answer

Which,if any,of the following aqueous mixtures would be a buffer system?

Correct AnswerverifiedShow Answer

The indicator propyl red has Ka = 3.3 ×\times× 10-6.What would be the approximate pH range over which it would change color?

Correct AnswerverifiedShow Answer

An acetic acid buffer containing 0.50 M CH3COOH and 0.50 M CH3COONa has a pH of 4.74.What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer?

Correct AnswerverifiedShow Answer

A 10.0-mL sample of 0.75 M CH3CH2COOH is titrated with 0.30 M NaOH.What is the pH of the solution after 22.0 mL of NaOH have been added to the acid? Ka = 1.3 ×\times× 10-5

Correct AnswerverifiedShow Answer

A buffer is to be prepared by adding solid sodium acetate to 0.10 M CH3COOH.Which of the following concentrations of sodium acetate will produce the most effective buffer?

Correct AnswerverifiedShow Answer

A solution is prepared by adding 100 mL of 0.2 M hydrochloric acid to 100 mL of 0.4 M sodium formate.Is this a buffer solution,and if so,what is its pH?

Correct AnswerverifiedShow Answer

Calculate the solubility of magnesium sulfate,MgSO4,when placed into a 0.10 M MgCl2 solution. Ksp = 5.9 ×\times× 10-3

Correct AnswerverifiedShow Answer

A 25.0-mL sample of 1.00 M NH3 is titrated with 0.15 M HCl.What is the pH of the solution after 15.00 mL of acid have been added to the ammonia solution? Kb = 1.8 ×\times× 10-5

Correct AnswerverifiedShow Answer

Correct Answer
verified

Calculate the solubility of copper(II)carbonate,CuCO₃,in 1.00 mol L^-1 NH₃.K_sp = 3.0 $\times$ 10^-12 for CuCO₃,K_f = 5.6 $\times$ 10¹¹ for Cu(NH₃)₄²⁺

Correct Answer
verified
0.16 mol L...
View Answer

Correct Answer
verified

If the pH of a buffer solution is greater than the pK_a value of the buffer acid,the buffer will have more capacity to neutralize added base than added acid.

Correct Answer
verified

The solubility of calcium chromate is 1.56 $\times$ 10^-3 g/100 mL of solution.What is the K_sp for CaCrO₄?

Correct Answer
verified

A buffer is prepared by adding 0.5 mol of solid sodium hydroxide to 1.0 L of 1.0 M acetic acid (CH₃COOH) .What is the pH of the buffer?

Correct Answer
verified

Correct Answer
verified

A 20.0-mL sample of 0.25 M HNO₃ is titrated with 0.15 M Na OH.What is the pH of the solution after 30.0 mL of NaOH have been added to the acid?

Correct Answer
verified

Fe(NO₃)₃ (0.00100 mol)and KSCN (0.200 mol)are added to water to make exactly 1 liter of solution.The red complex ion FeSCN²⁺ is produced.Calculate the concentrations of Fe³⁺(aq)and FeSCN²⁺(aq)at equilibrium,if K_f of the FeSCN²⁺ is 8.9 $\times$ 10².

Correct Answer
verified
[Fe³⁺] = 5.6 10
View Answer

Correct Answer
verified

Citric acid has an acid dissociation constant of 8.4 $\times$ 10^-4.It would be most effective for preparation of a buffer with a pH of

Correct Answer
verified

Calculate the solubility of silver chromate,Ag₂CrO₄,in 0.005 M Na₂CrO₄.K_sp = 2.6 $\times$ 10^-12

Correct Answer
verified

Correct Answer
verified

The indicator propyl red has K_a = 3.3 $\times$ 10^-6.What would be the approximate pH range over which it would change color?

Correct Answer
verified

An acetic acid buffer containing 0.50 M CH₃COOH and 0.50 M CH₃COONa has a pH of 4.74.What will the pH be after 0.0020 mol of HCl has been added to 100.0 mL of the buffer?

Correct Answer
verified

A 10.0-mL sample of 0.75 M CH₃CH₂COOH is titrated with 0.30 M NaOH.What is the pH of the solution after 22.0 mL of NaOH have been added to the acid? K_a = 1.3 $\times$ 10^-5

Correct Answer
verified

A buffer is to be prepared by adding solid sodium acetate to 0.10 M CH₃COOH.Which of the following concentrations of sodium acetate will produce the most effective buffer?

Correct Answer
verified

Correct Answer
verified

Calculate the solubility of magnesium sulfate,MgSO₄,when placed into a 0.10 M MgCl₂ solution. K_sp = 5.9 $\times$ 10^-3

Correct Answer
verified

A 25.0-mL sample of 1.00 M NH₃ is titrated with 0.15 M HCl.What is the pH of the solution after 15.00 mL of acid have been added to the ammonia solution? K_b = 1.8 $\times$ 10^-5

Correct Answer
verified