Exam 2B, Spring 2000

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

a. C₆H₅NH₂(aq) + HBr(aq)

b. C₂H₅COOH(aq) + H₂O(l)

c. (C₂H₅)₃N(aq) + H₂O(l)

d. HNO₂(aq) + KOH(aq)

2. Find the pH, pOH, [H₃O⁺], and [OH^–] for the following solutions at 25 °C.

a. 0.025 M perchloric acid.

b. 4.2×10^–4 M calcium hydroxide

c. acetic acid solution with pH = 3.15

d. ammonia solution with pH = 10.32

e. 0.00056 M sodium hydroxide

3. Indicate the stronger acid in each pair. Explain your reasoning in 5 words or less.

a. HNO₃ vs. H₂SO₄

b. CCl₃COOH vs. CH₃COOH

c. H₂Se vs. H₂Te

d. H₂SeO₄ vs. HSeO₄^–

4. Find the pH of a 0.072 M solution of hypobromous acid, HOBr. Show the appropriate chemical reaction required to solve the problem.

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