Unit 5: Acids and Bases Review

Which equation show NH₃ act as an acid?

• NH₃ + H₂O <--> NH^₄+ + OH^-

• NH₃ + H₂O <--> NH₂^- + H₃O⁺

• NH₃ + H₂O <--> NH₂^- + OH^-

• NH₃ + H₂O <-->NH^₄+ + H₃O⁺

Which equation show NH₃ act as an base?

• NH₃ + H₂O <--> NH^₄+ + OH^-

• NH₃ + H₂O <--> NH₂^- + H₃O⁺

• NH₃ + H₂O <--> NH₂^- + OH^-

• NH₃ + H₂O <-->NH^₄+ + H₃O⁺

What is the conjugate acid (bottom row) of the base (top row) of each of the following?

• H2SO4

• H2O

• H3O+

• NH3

• H2O

• OH-

• NH4+

• HCO3-

• H2CO3

• HSO4-

Calculate the pH and the pOH of each of 0.200 M HCl at 25 °C for which the substances ionize completely.

• pH = 0.7, pOH = 13.3

• pH = 1, pOH = 13

• pH = 0.3, pOH = 13.7

• pH = 12, pOH = 2

What are the hydronium and hydroxide ion concentrations in a solution whose pH is 6.52?

• [H₃O+]: 3.02 x 10^-7 M, [OH-]: 3.31 x 10^-8 M

• [H₃O+]: 2.10 x 10^-6 M, [OH-]: 4.76 x 10^-9 M

• [H₃O+]: 3.02 x 10^-7 M, [OH-]: 3.02 x 10^-7 M

• [H₃O+]: 1.20 x 10^-6 M, [OH-]: 8.32 x 10^-9 M

The hydronium ion concentration in a sample of rainwater is found to be 1.7 x 10^-6 M at 25 °C. What is the concentration of hydroxide ions in the rainwater?

• 1.7 x 10^-7 M

• 1.7 x 10^-6 M

• 5.9 x 10^-6 M

• 5.9 x 10^-9 M

Why does the neutralization reaction of a strong acid and a weak base give a weakly acidic solution?

• The resulting solution is neutral because all neutralization reactions result in a neutral solution.

• The resulting solution is strongly acidic due to the complete dissociation of the strong acid.

• The resulting solution is weakly acidic due to the incomplete dissociation of the weak base.

• The resulting solution is weakly acidic because the strong acid completely neutralizes the weak base.

Why is the ionization constant, K_a, for H₂SO₄ is larger than the ionization constant for H₂SO₃?

• H₂SO₄ is a stronger acid because it is more stable after gaining a proton.

• H₂SO₃ has a larger atomic size, making it a stronger acid.

• H₂SO₄ has a higher molecular weight, which increases its Ka.

• H₂SO₄ dissociates more because it is a strong acid.

What is the ionization constant (K_a) at 25 °C for the weak acid CH₃NH₃⁺?

The conjugate acid of the weak base is CH₃NH₂ and has a K_b = 4.4 × 10⁻⁴ and K_w = 1 x 10^-14

• 4.4 x 10^-3

• 2.3 x 10^-11

• 6.4 x 10^-5

• 7.1 x 10^-6

Are the concentrations of hydronium ion and hydroxide ion in a solution of an acid or a base in water directly proportional or inversely proportional?

• Directly proportional

• Inversely proportional

• Neither directly nor inversely proportional

• Depends on the solution