Exam 2B, Spring 2002

1. Complete and balance the following acid/base reactions. Label the acid, base, conjugate acid, and conjugate base for each reaction.

a. aqueous perchloric acid plus solid magnesium hydroxide

b. aqueous nitric acid plus water

c. HBr(aq) + CN^–(aq)

d. HClO₃(aq) + H₂O(l)

2. Write the chemical reaction needed to determine the pH and give the pH for the following solutions.

a. 0.0010 M hydroiodic acid.

b. 0.0010 M calcium hydroxide

3. Indicate the stronger acid in each pair. Explain your reasoning in 5 words or less. For the stronger acid, write out the balanced reaction of the acid with water.

a. CF₃COOH vs. CH₃COOH

b. H₄SiO₄ vs. H₃PO₄

c. HCrO₄^– vs. HMnO₄

4. Complete the following reactions and indicate which direction equilibrium will favor:

a. HBrO₂(aq) + ClO₂^–(aq)

b. NH₃(aq) + HF(aq)

5. A 0.0010 M solution of fluoroacetic acid (CH₂FCO₂H, K_a = 2.6×10^–3) was prepared. Find the pH.

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