The acid-dissociation constants of phosphoric acid (H2PO3)are Kal = 7.5 × 10-3, Ka2 = 6.2 × 10-8, and Ka3 = 4.2 × 10-13 at 25.0°C. What is the pH of a 2.5 M aqueous solution of phosphoric acid?

A) 1.82 B) 0.40 C) 2.51 D) 0.86 E) 0.13 A) 1.82 B) 0.40 C) 2.51 D) 0.86 E) 0.13

Calculate the pOH of a solution at 25.0 °C that contains 1.94 × 10-10 M hydronium ions.

A) 1.94 B) 4.29 C) 7.00 D) 14.0 E) 9.71 A) 1.94 B) 4.29 C) 7.00 D) 14.0 E) 9.71

The pH of a 0.55 M aqueous solution ammonia, NH3, at 25.0°C is 11.50. What is the value of Kb for NH3?

A) 2.0 × 10-9 B) 1.1 × 10-9 C) 6.0 × 10-5 D) 1.8 × 10-5 E) none of the above A) 2.0 × 10-9 B) 1.1 × 10-9 C) 6.0 × 10-5 D) 1.8 × 10-5 E) none of the above

The Ka of acetic acid (HC2H3O2)is 1.8 × 10-5. What is the pH at 25.0°C of an aqueous solution that is 0.100 M in acetic acid?

A) +2.87 B) -2.87 C) -11.13 D) +11.13 E) +6.61 A) +2.87 B) -2.87 C) -11.13 D) +11.13 E) +6.61

The conjugate base of HSO4- is __________.

A) OH- B) H2SO4 C) SO42- D) HSO4+ E) H3SO4+ A) OH- B) H2SO4 C) SO42- D) HSO4+ E) H3SO4+

Exam 16: Acid-Base Equilibria

The acid-dissociation constants of phosphoric acid (H₂PO₃)are K_al = 7.5 × 10^-³, K_a2 = 6.2 × 10^-⁸, and K_a3 = 4.2 × 10^-¹³ at 25.0°C. What is the pH of a 2.5 M aqueous solution of phosphoric acid?

(Multiple Choice)

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Question 21

Calculate the pOH of a solution at 25.0 °C that contains 1.94 × 10^-¹⁰ M hydronium ions.

(Multiple Choice)

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Question 22

The K_a for formic acid (HCO₂H)is 1.8 × 10^-4. What is the pH of a 0.10 M aqueous solution of sodium formate (NaHCO₂)?

(Multiple Choice)

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Question 23

What is the pH of a sodium acetate solution prepared by adding 0.820 grams of sodium acetate to 100.0 ml of water at 25.0°C? The K_a at 25.0°C for acetic acid is 1.8 × 10^-5.

(Short Answer)

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Question 24

The pH of a 0.55 M aqueous solution ammonia, NH₃, at 25.0°C is 11.50. What is the value of K_b for NH₃?

(Multiple Choice)

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Question 25

What is the concentration (in M)of hydroxide ions in a solution at 25.0 °C with pH = 4.153?

(Multiple Choice)

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Question 26

What is the pH of an aqueous solution at 25.0 °C that contains 3.98 × 10^-⁹ M hydroxide ion?

(Multiple Choice)

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Question 27

The pH of a 0.55 M aqueous solution of hypobromous acid, HBrO, at 25.0°C is 4.48. What is the value of K_a for HBrO?

(Multiple Choice)

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Question 28

HZ is a weak acid. An aqueous solution of HZ is prepared by dissolving 0.020 mol of HZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 4.93 at 25.0°C. The K_a of HZ is __________.

(Multiple Choice)

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Question 29

A Lewis acid is an electron-pair acceptor, and a Lewis base is an electron-pair donor.

(True/False)

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Question 30

Z^- is a weak base. An aqueous solution of NaZ is prepared by dissolving 0.350 mol of NaZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 8.93 at 25.0°C. The K_b of Z^-is __________.

(Multiple Choice)

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Question 31

Of the following, __________ is a weak acid.

(Multiple Choice)

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Question 32

What is the pOH of an aqueous solution at 25.0 °C that contains 3.98 × 10^-9 M hydronium ion?

(Multiple Choice)

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Question 33

The acid-dissociation constant, K_a, for gallic acid is 4.57 × 10^-3. What is the base-dissociation constant, K_b, for the gallate ion?

(Multiple Choice)

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Question 34

The K_a of acetic acid (HC₂H₃O₂)is 1.8 × 10^-⁵. What is the pH at 25.0°C of an aqueous solution that is 0.100 M in acetic acid?

(Multiple Choice)

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Question 35

What is the pH of a 0.035 M aqueous solution of barium hydroxide?

(Multiple Choice)

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Question 36

A solution of ammonia is 2.0% ionized at 25.0°C. What was the original concentration (in M)of the ammonia solution? The K_b at 25.0°C for ammonia is 1.8 × 10^-5.

(Short Answer)

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Question 37

The conjugate base of HSO₄^- is __________.

(Multiple Choice)

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Question 38

Using the data in the table, which of the conjugate bases below is the weakest base?

(Multiple Choice)

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Question 39

HA is a weak acid. Which equilibrium corresponds to the equilibrium constant K_b for A^-?

(Multiple Choice)

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Question 40

Showing 21 - 40 of 134

Exam 16: Acid-Base Equilibria

The acid-dissociation constants of phosphoric acid (H2PO3)are Kal = 7.5 × 10-3, Ka2 = 6.2 × 10-8, and Ka3 = 4.2 × 10-13 at 25.0°C. What is the pH of a 2.5 M aqueous solution of phosphoric acid?

Calculate the pOH of a solution at 25.0 °C that contains 1.94 × 10-10 M hydronium ions.

The Ka for formic acid (HCO2H)is 1.8 × 10-4. What is the pH of a 0.10 M aqueous solution of sodium formate (NaHCO2)?

What is the pH of a sodium acetate solution prepared by adding 0.820 grams of sodium acetate to 100.0 ml of water at 25.0°C? The Ka at 25.0°C for acetic acid is 1.8 × 10-5.

The pH of a 0.55 M aqueous solution ammonia, NH3, at 25.0°C is 11.50. What is the value of Kb for NH3?

What is the concentration (in M)of hydroxide ions in a solution at 25.0 °C with pH = 4.153?

What is the pH of an aqueous solution at 25.0 °C that contains 3.98 × 10-9 M hydroxide ion?

The pH of a 0.55 M aqueous solution of hypobromous acid, HBrO, at 25.0°C is 4.48. What is the value of Ka for HBrO?

HZ is a weak acid. An aqueous solution of HZ is prepared by dissolving 0.020 mol of HZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 4.93 at 25.0°C. The Ka of HZ is __________.

A Lewis acid is an electron-pair acceptor, and a Lewis base is an electron-pair donor.

Z- is a weak base. An aqueous solution of NaZ is prepared by dissolving 0.350 mol of NaZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 8.93 at 25.0°C. The Kb of Z- is __________.

Of the following, __________ is a weak acid.

What is the pOH of an aqueous solution at 25.0 °C that contains 3.98 × 10-9 M hydronium ion?

The acid-dissociation constant, Ka, for gallic acid is 4.57 × 10-3. What is the base-dissociation constant, Kb, for the gallate ion?

The Ka of acetic acid (HC2H3O2)is 1.8 × 10-5. What is the pH at 25.0°C of an aqueous solution that is 0.100 M in acetic acid?

What is the pH of a 0.035 M aqueous solution of barium hydroxide?

A solution of ammonia is 2.0% ionized at 25.0°C. What was the original concentration (in M)of the ammonia solution? The Kb at 25.0°C for ammonia is 1.8 × 10-5.

The conjugate base of HSO4- is __________.

Using the data in the table, which of the conjugate bases below is the weakest base?

HA is a weak acid. Which equilibrium corresponds to the equilibrium constant Kb for A-?

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The acid-dissociation constants of phosphoric acid (H₂PO₃)are K_al = 7.5 × 10^-³, K_a2 = 6.2 × 10^-⁸, and K_a3 = 4.2 × 10^-¹³ at 25.0°C. What is the pH of a 2.5 M aqueous solution of phosphoric acid?

Calculate the pOH of a solution at 25.0 °C that contains 1.94 × 10^-¹⁰ M hydronium ions.

The K_a for formic acid (HCO₂H)is 1.8 × 10^-4. What is the pH of a 0.10 M aqueous solution of sodium formate (NaHCO₂)?

What is the pH of a sodium acetate solution prepared by adding 0.820 grams of sodium acetate to 100.0 ml of water at 25.0°C? The K_a at 25.0°C for acetic acid is 1.8 × 10^-5.

The pH of a 0.55 M aqueous solution ammonia, NH₃, at 25.0°C is 11.50. What is the value of K_b for NH₃?

What is the pH of an aqueous solution at 25.0 °C that contains 3.98 × 10^-⁹ M hydroxide ion?

The pH of a 0.55 M aqueous solution of hypobromous acid, HBrO, at 25.0°C is 4.48. What is the value of K_a for HBrO?

HZ is a weak acid. An aqueous solution of HZ is prepared by dissolving 0.020 mol of HZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 4.93 at 25.0°C. The K_a of HZ is __________.

Z^- is a weak base. An aqueous solution of NaZ is prepared by dissolving 0.350 mol of NaZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 8.93 at 25.0°C. The K_b of Z^-is __________.

What is the pOH of an aqueous solution at 25.0 °C that contains 3.98 × 10^-9 M hydronium ion?

The acid-dissociation constant, K_a, for gallic acid is 4.57 × 10^-3. What is the base-dissociation constant, K_b, for the gallate ion?

The K_a of acetic acid (HC₂H₃O₂)is 1.8 × 10^-⁵. What is the pH at 25.0°C of an aqueous solution that is 0.100 M in acetic acid?

A solution of ammonia is 2.0% ionized at 25.0°C. What was the original concentration (in M)of the ammonia solution? The K_b at 25.0°C for ammonia is 1.8 × 10^-5.

The conjugate base of HSO₄^- is __________.

HA is a weak acid. Which equilibrium corresponds to the equilibrium constant K_b for A^-?