Ka and Kb Calculations

Acetic Acid is a weak monoprotic acid. It's concentration is 0.20M and it's equilibrium concentration of H+ ions is 0.0019M. Calculate it's Ka value.

• 1.8x10 -5

• 1.8x10 -15

• .0019

• 5.56x10 -10

Formic Acid is a weak monoprotic acid. It's initial concentration is 0.10M and it's equilibrium concentration of H+ ions is 0.0042M. Calculate it's Ka value.

• .150

• 12.56x10 -6

• 1.8x10 -4

• None of these are correct

Isobutlyamine is a weak base. It's initial concentration is 0.55M and it's equilibrium concentration of OH- ions is 0.0040M. Calculate it's Kb value.

• .055

• 4.0 x 10 -3

• 1.6 x 10 -5

• 2.9 x 10 -5

Acetic Acid is a weak monoprotic acid. It's concentration is 0.20M and it's Ka value is 1.8x10 -5. Calculate it's pH value.

• .698

• 2.72

• 11.28

• None of the answers are correct

Ammonia is a weak base. It's concentration is 0.150M and it's Kb value is 1.7x10 ^-5. Calculate it's pH value.

• 2.80

• 11.2

• Both answers are correct

• None of the above are correct

Butylamine is a weak base. It's concentration is 0.230M and it's equilibrium concentration of OH- ions is 8.6x10^-6M. Calculate it's Kb value and pOH.

• 3.2x10 -10 and 9.49

• 8.6x10 -10 and 9.07

• 3.2x10 -10 and 4.93

• None of the above

Which of the following substances has the greatest solubility in water?

• MgCO₃, Ksp = 3.5 × 10^–8

• CuBr, Ksp = 5.0 × 10^–9

• NiCO₃, Ksp = 1.3 × 10^–7

• AgCN, Ksp = 2.2 × 10^–16

• AgIO₃, Ksp = 3.1 × 10^–8

Consider the following balanced redox reaction

Mn²⁺(aq) + S₂O₈^2– (aq) + 2 H₂O(l) →

MnO₂(s) + 4 H⁺ (aq) + 2 SO₄^2– (aq)

Which of the following statements is true?

• Mn²⁺(aq) is the oxidizing agent and is reduced.

• Mn²⁺(aq) is the oxidizing agent and is oxidized.

• Mn²⁺(aq) is the reducing agent and is oxidized.

• Mn²⁺(aq) is the reducing agent and is reduced.

• Manganese does not change its oxidation number in this reaction.

In a 0.0100 M solution of a hypothetical weak acid HW, it is found that the [H₃O+] = 2.50 x 10^-3 M. K_a for the acid is:

• 6.25 x 10^-4

• 8.33 x 10^-4

• 2.50 x 10^-1

• 6.25 x 10^-2

• 6.25 x 10^-6

A student mixes 0.080 moles of nitric acid in water to form 1.0 liter of solution and measures the pH of the resulting solution. What pH value should the student obtain?

• 0.08

• 1.39

• 1.10

• -1.10

• 5.25