Exam 2B, Spring 2004

1. Complete and balance the following reactions:

a. H₂SO₄(aq) + KOH(aq)

b. C₆H₅NH₂(aq) + HBr(aq)

c. HOBr(aq) + H₂O(l)

d. Mg(OH)₂(s) + HNO₃(aq)

2. Complete and balance the following reaction and identify the acid, the base, the conjugate acid, and the conjugate base:

CO₃^2–(aq) + CH₃CH₂CO₂H(aq)

3. Identify the Lewis acid and the Lewis base in the following reaction.

Al(OH)₃(s) + OH^–(aq) → Al(OH)₄^–(aq)

4. Identify the stronger acid in pair given below. Briefly (5 words or less) justify your reasoning.

a. H₂O or H₂S

b. H₂SeO₄ or H₂TeO₄

5. Calculate the pH and pOH of the following solutions:

a. 2.0×10^–4 M perchloric acid.

b. 2.0×10^–4 M potassium hydroxide.

c. 3.0×10^–4 M calcium hydroxide.

6. Consider the reaction shown below, which has ΔH = 131 kJ/mol.

C(s) + H₂O(g) → ← CO(g) + H₂(g)

a. Which way will the reaction shift if the pressure is decreased by expanding the volume?

b. Which way will the reaction shift if the temperature is lowered?

7. Estimate the pH of a 2.0×10^–4 M solution of HNO₂. K_a = 7.2×10^–4

Answers