Exam 2B, Spring 1999

1. Identify the acid, base,conjugate acid, and conjugate base in the following reaction:

HI(aq) + (CH₃)NH₂(aq) → (CH₃)NH₃⁺(aq) + I^–(aq)

2. Identify the Lewis acid and Lewis base in the following reaction:

Co²⁺(aq) + 6 H₂O(l) → ← Co(H₂O)₆²⁺(aq)

3. Complete and balance the following reactions:

a. HNO₃(aq) + H₂O(l)

b. NH₄⁺(aq) + H₂O(l)

c. H₂CO₃(aq) + HS^–(aq)

d. HCN(aq) + PO₄^3–(aq)

4. Find the pH of the following solutions at 25 °C:

a. 0.0012 M nitric acid

b. 1.00 g of hydrogen bromide dissolved in 1.00 L of water

c. 7.3×10^–5 M solution of calcium hydroxide.

5. Find the hydronium ion and hydroxide ion concentrations for the following solutions at 25 °C:

a. a perchloric acid solution with pH = 4.16

b. a solution prepared by dissolving 1.00 g of rubidium hydroxide in 1.00 L of water

c. a 9.2×10^–4 M solution of magnesium hydroxide

d. a potassium hydroxide solution with pOH = 2.8

6. For each of the following, indicate the stronger acid.

a. H₂S, H₂Te

b. HClO₃, HClO₂

c. NH₃, NH₂^–

7. A 0.0012 M solution of an acid was found to be 0.064% ionized at 25 °C. Find the pK_a of the acid.

8. Find the pH of a 0.21 M solution of hydrocyanic acid, HCN, at 25 °C.

Answers