Question 1

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 B)
G) B) and E)

Question 2

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

Question 3

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 × 10−5

Accepted Answer

A)  10.26
B)  9.30
C)  9.21
D)  8.30
E)  8.21F) None of the above
G) C) and D)

Question 4

A lab technician adds 0.20 mol of NaF to 1.00 L of 0.35 M cadmium nitrate, Cd(NO3) 2. Which of the following statements is correct? Ksp = 6.44 × 10−3 for CdF2.

Accepted Answer

A)  Cadmium fluoride precipitates until the solution is saturated.
B)  The solution is unsaturated and no precipitate forms.
C)  The solubility of cadmium fluoride is increased by the presence of additional fluoride ions.
D)  One must know K sp for cadmium nitrate to make meaningful predictions on this system.
E)  The presence of NaF will raise the solubility of Cd(NO 3) 2.F) C) and D)
G) None of the above

Question 5

What is the pH of a solution that consists of 0.50 M H2C6H6O6 (ascorbic acid)  and 0.75 M NaHC6H6O6 (sodium ascorbate) ? For ascorbic acid, Ka = 6.8 × 10−5

Accepted Answer

A)  3.76
B)  3.99
C)  4.34
D)  4.57
E)  5.66F) B) and C)
G) A) and D)

Question 6

Write the ion product expression for silver sulfide, Ag2S.

Accepted Answer

A)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
B)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
C)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
D)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >
E)   2S. 
A)     
B)     
C)     
D)     
E)    " class="answers-bank-image d-inline" rel="preload" >F) None of the above
G) A) and B)

Question 7

For a diprotic acid H2A, the relationship Ka1 > Ka2 is always true.

Accepted Answer

A) True 
 B)False

Question 8

A 25.0-mL sample of 0.10 M C2H3NH2 (ethylamine)  is titrated with 0.15 M HCl. What is the pH of the solution after 9.00 mL of acid have been added to the amine? Kb = 6.5 × 10−4

Accepted Answer

A)  11.08
B)  10.88
C)  10.74
D)  10.55
E)  10.49F) A) and D)
G) A) and C)

Question 9

Increasing the concentrations of the components of a buffer solution will increase the buffer capacity.

Accepted Answer

A) True 
 B)False

Question 10

When a weak acid is titrated with a strong 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 p K a of the acid.
E)  is equal to 14.0 − p K b, where p K b is that of the base.F) B) and E)
G) B) and D)

Question 11

A buffer is prepared by adding 300.0 mL of 2.0 M NaOH to 500.0 mL of 2.0 M CH3COOH. What is the pH of this buffer? Ka = 1.8 × 10−5

Accepted Answer

A)  4.57
B)  4.52
C)  4.87
D)  4.92
E)  4.97F) A) and C)
G) B) and C)

Question 12

A popular buffer solution consists of carbonate (CO32−)  and hydrogen carbonate (HCO3−)  conjugate acid-base pair. Which, if any, of the following such buffers has the highest buffer capacity?

Accepted Answer

A)  0.9 M CO 3 2− and 0.1 M HCO 3 −
B)  0.1 M CO 3 2− and 0.9 M HCO 3 −
C)  0.5 M CO 3 2− and 0.5 M HCO 3 −
D)  0.1 M CO 3 2− and 0.1 M HCO 3 −
E)  They all have the same buffer capacity.F) A) and D)
G) None of the above

Question 13

The salts X(NO3) 2 and Y(NO3) 2 (where X+ and Y+ are metal ions)  are dissolved in water to give a solution which is 0.1 M in each of them. Which of the answers gives the concentration of chloride ions will precipitate the most YCl2 without precipitating any XCl2? Given Ksp values: XCl2, 2 × 10−5 YCl2, 1 × 10−10

Accepted Answer

A)  1 M Cl −
B)  0.1 M Cl −
C)  0.01 M Cl −
D)  0.001 M Cl −
E)  0.0001 M Cl −F) A) and D)
G) A) and E)

Question 14

Which of the following has the highest buffer capacity?

Accepted Answer

A)  0.10 M H 2PO 4 −/0.10 M HPO 4 2−
B)  0.50 M H 2PO 4 −/0.10 M HPO 4 2−
C)  0.10 M H 2PO 4 −/0.50 M HPO 4 2−
D)  0.50 M H 2PO 4 −/0.50 M HPO 4 2−
E)  They all have the same buffer capacity.F) D) and E)
G) B) and D)

Question 15

The solubility of aluminum hydroxide in water __________ when dilute nitric acid is added to it.

Accepted Answer

A)  increases
B)  decreases
C)  does not change
D)  first increases, then decreases
E)  first decreases, then increasesF) B) and C)
G) A) and B)

Question 16

A lab technician adds 0.015 mol of KOH to 1.00 L of 0.0010 M Ca(NO3) 2. Ksp = 6.5 × 10−6 for Ca(OH) 2) . Which of the following statements is correct?

Accepted Answer

A)  Calcium hydroxide precipitates until the solution is saturated.
B)  The solution is unsaturated and no precipitate forms.
C)  The concentration of calcium ions is reduced by the addition of the hydroxide ions.
D)  One must know K sp for calcium nitrate to make meaningful predictions on this system.
E)  The presence of KOH will raise the solubility of Ca(NO 3) 2.F) All of the above
G) C) and D)

Question 17

Use the following information to calculate the solubility product constant, Ksp, for CuCl. A saturated solution of CuCl in water was prepared and filtered. From the filtrate, 1.0 L was measured out into a beaker and evaporated to dryness. The solid CuCl residue recovered in the beaker was found to weigh 0.041g.

Accepted Answer

A)  K sp = 1.7 × 10 y9
B)  K sp = 1.7 × 10 y7
C)  K sp = 1.7 × 10 −5
D)  K sp = 4.3 × 10 −4
E)  K sp = 2.1 × 10 −2F) A) and B)
G) A) and E)

Question 18

If 10.0 g of NaF and 20.0 g of HF are dissolved in water to make one liter of solution, what will the pH be? For HF, Ka = 6.8 × 10−4.

Accepted Answer

A)  7.13
B)  2.54
C)  1.57
D)  3.17
E)  4.86F) A) and E)
G) A) and D)

Question 19

A phosphate buffer (H2PO4−/HPO42−)  has a pH of 8.3. Which of the following changes will cause the pH to increase?

Accepted Answer

A)  Dissolving a small amount of Na 2HPO 4
B)  Dissolving a small amount of NaH 2PO 4
C)  Adding a small amount of dilute hydrochloric acid
D)  Adding a small amount of dilute phosphoric acid
E)  Making the buffer more concentrated by removing some waterF) All of the above
G) C) and D)

Question 20

A 20.0-mL sample of 0.50 M H2C6H6O6 (ascorbic acid, a diprotic acid)  was titrated with 0.50 M NaOH. The following data were gathered during the titration. 2C6H6O6 (ascorbic acid, a diprotic acid)  was titrated with 0.50 M NaOH. The following data were gathered during the titration.   What is Ka2 for ascorbic acid? A) 6.8 × 10 −5 B) 6.2 × 10 −6 C) 6.2 × 10 −7 D) 6.2 × 10 −8 E) 2.8 × 10 −12" class="answers-bank-image d-inline" rel="preload" > What is Ka2 for ascorbic acid?

Accepted Answer

A)  6.8 × 10 −5
B)  6.2 × 10 −6
C)  6.2 × 10 −7
D)  6.2 × 10 −8
E)  2.8 × 10 −12F) C) and D)
G) A) and B)

Exam 19: Ionic Equilibria in Aqueous Systems

Correct Answer
verified

Correct Answer
verified

For a diprotic acid H₂A, the relationship K_a1 > K_a2 is always true.

Correct Answer
verified

What is the pH of a solution that consists of 0.50 M H₂C₆H₆O₆ (ascorbic acid) and 0.75 M NaHC₆H₆O₆(sodium ascorbate) ? For ascorbic acid, K_a = 6.8 × 10⁻⁵

Correct Answer
verified

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

Correct Answer
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A phosphate buffer (H₂PO₄⁻/HPO₄²⁻) has a pH of 8.3. Which of the following changes will cause the pH to increase?

Correct Answer
verified

Which of the following has the highest buffer capacity?

Correct Answer
verified

A buffer is prepared by adding 300.0 mL of 2.0 M NaOH to 500.0 mL of 2.0 M CH₃COOH. What is the pH of this buffer? K_a = 1.8 × 10⁻⁵

Correct Answer
verified

If 10.0 g of NaF and 20.0 g of HF are dissolved in water to make one liter of solution, what will the pH be? For HF, K_a = 6.8 × 10⁻⁴.

Correct Answer
verified

The solubility of aluminum hydroxide in water __________ when dilute nitric acid is added to it.

Correct Answer
verified

A 25.0-mL sample of 0.10 M C₂H₃NH₂(ethylamine) is titrated with 0.15 M HCl. What is the pH of the solution after 9.00 mL of acid have been added to the amine? K_b = 6.5 × 10⁻⁴

Correct Answer
verified

A 25.0-mL sample of 1.00 M NH₃is 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 × 10⁻⁵

Correct Answer
verified

A 20.0-mL sample of 0.50 M H₂C₆H₆O₆(ascorbic acid, a diprotic acid) was titrated with 0.50 M NaOH. The following data were gathered during the titration. What is K_a2 for ascorbic acid?

Correct Answer
verified

Increasing the concentrations of the components of a buffer solution will increase the buffer capacity.

Correct Answer
verified

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 Answer
verified

A lab technician adds 0.20 mol of NaF to 1.00 L of 0.35 M cadmium nitrate, Cd(NO₃) ₂. Which of the following statements is correct? K_sp = 6.44 × 10⁻³ for CdF₂.

Correct Answer
verified

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 Answer
verified

A popular buffer solution consists of carbonate (CO₃²⁻) and hydrogen carbonate (HCO₃⁻) conjugate acid-base pair. Which, if any, of the following such buffers has the highest buffer capacity?

Correct Answer
verified

A lab technician adds 0.015 mol of KOH to 1.00 L of 0.0010 M Ca(NO₃) ₂. K_sp = 6.5 × 10⁻⁶ for Ca(OH) ₂) . Which of the following statements is correct?

Correct Answer
verified

Write the ion product expression for silver sulfide, Ag₂S.

Correct Answer
verified

Exam 19: Ionic Equilibria in Aqueous Systems

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

For a diprotic acid H2A, the relationship Ka1 > Ka2 is always true.

Correct AnswerverifiedShow Answer

What is the pH of a solution that consists of 0.50 M H2C6H6O6 (ascorbic acid) and 0.75 M NaHC6H6O6 (sodium ascorbate) ? For ascorbic acid, Ka = 6.8 × 10−5

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

A phosphate buffer (H2PO4−/HPO42−) has a pH of 8.3. Which of the following changes will cause the pH to increase?

Correct AnswerverifiedShow Answer

Which of the following has the highest buffer capacity?

Correct AnswerverifiedShow Answer

A buffer is prepared by adding 300.0 mL of 2.0 M NaOH to 500.0 mL of 2.0 M CH3COOH. What is the pH of this buffer? Ka = 1.8 × 10−5

Correct AnswerverifiedShow Answer

If 10.0 g of NaF and 20.0 g of HF are dissolved in water to make one liter of solution, what will the pH be? For HF, Ka = 6.8 × 10−4.

Correct AnswerverifiedShow Answer

The solubility of aluminum hydroxide in water __________ when dilute nitric acid is added to it.

Correct AnswerverifiedShow Answer

A 25.0-mL sample of 0.10 M C2H3NH2 (ethylamine) is titrated with 0.15 M HCl. What is the pH of the solution after 9.00 mL of acid have been added to the amine? Kb = 6.5 × 10−4

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 × 10−5

Correct AnswerverifiedShow Answer

A 20.0-mL sample of 0.50 M H2C6H6O6 (ascorbic acid, a diprotic acid) was titrated with 0.50 M NaOH. The following data were gathered during the titration. What is Ka2 for ascorbic acid?

Correct AnswerverifiedShow Answer

Increasing the concentrations of the components of a buffer solution will increase the buffer capacity.

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 lab technician adds 0.20 mol of NaF to 1.00 L of 0.35 M cadmium nitrate, Cd(NO3) 2. Which of the following statements is correct? Ksp = 6.44 × 10−3 for CdF2.

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

A popular buffer solution consists of carbonate (CO32−) and hydrogen carbonate (HCO3−) conjugate acid-base pair. Which, if any, of the following such buffers has the highest buffer capacity?

Correct AnswerverifiedShow Answer

A lab technician adds 0.015 mol of KOH to 1.00 L of 0.0010 M Ca(NO3) 2. Ksp = 6.5 × 10−6 for Ca(OH) 2) . Which of the following statements is correct?

Correct AnswerverifiedShow Answer

Write the ion product expression for silver sulfide, Ag2S.

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

For a diprotic acid H₂A, the relationship K_a1 > K_a2 is always true.

Correct Answer
verified

What is the pH of a solution that consists of 0.50 M H₂C₆H₆O₆ (ascorbic acid) and 0.75 M NaHC₆H₆O₆(sodium ascorbate) ? For ascorbic acid, K_a = 6.8 × 10⁻⁵

Correct Answer
verified

Correct Answer
verified

A phosphate buffer (H₂PO₄⁻/HPO₄²⁻) has a pH of 8.3. Which of the following changes will cause the pH to increase?

Correct Answer
verified

Correct Answer
verified

A buffer is prepared by adding 300.0 mL of 2.0 M NaOH to 500.0 mL of 2.0 M CH₃COOH. What is the pH of this buffer? K_a = 1.8 × 10⁻⁵

Correct Answer
verified

If 10.0 g of NaF and 20.0 g of HF are dissolved in water to make one liter of solution, what will the pH be? For HF, K_a = 6.8 × 10⁻⁴.

Correct Answer
verified

Correct Answer
verified

A 25.0-mL sample of 0.10 M C₂H₃NH₂(ethylamine) is titrated with 0.15 M HCl. What is the pH of the solution after 9.00 mL of acid have been added to the amine? K_b = 6.5 × 10⁻⁴

Correct Answer
verified

A 25.0-mL sample of 1.00 M NH₃is 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 × 10⁻⁵

Correct Answer
verified

A 20.0-mL sample of 0.50 M H₂C₆H₆O₆(ascorbic acid, a diprotic acid) was titrated with 0.50 M NaOH. The following data were gathered during the titration. What is K_a2 for ascorbic acid?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

A lab technician adds 0.20 mol of NaF to 1.00 L of 0.35 M cadmium nitrate, Cd(NO₃) ₂. Which of the following statements is correct? K_sp = 6.44 × 10⁻³ for CdF₂.

Correct Answer
verified

Correct Answer
verified

A popular buffer solution consists of carbonate (CO₃²⁻) and hydrogen carbonate (HCO₃⁻) conjugate acid-base pair. Which, if any, of the following such buffers has the highest buffer capacity?

Correct Answer
verified

A lab technician adds 0.015 mol of KOH to 1.00 L of 0.0010 M Ca(NO₃) ₂. K_sp = 6.5 × 10⁻⁶ for Ca(OH) ₂) . Which of the following statements is correct?

Correct Answer
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Write the ion product expression for silver sulfide, Ag₂S.

Correct Answer
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