1. Lecture 193/3/06

2. QUIZ 1. True or False: Buffer solutions are always at pH 7. 2. For each pair, which will have a lower pH? 1. 0.1 M HNO 3 or0.1 M NH 4 NO 3 2. 0.1 M HNO 3 or 0.3 M HNO 3 3. 0.1 M HNO 3 or 0.1 M H 2 SO 4 4. 0.1 M HNO 3 or 0.1 M NaNO 3 5. 0.1 M HNO 3 or 0.1 M HNO 2 6. 0.1 M NaNO 3 or 0.1 M HNO 2 7. 0.1 M NaNO 3 or 0.1 M Al(NO 3 ) 3

3. Optional Spring Break Quizzes 1. 1-page essay - how chemistry impacted you during spring break 2. 1-page critique of 2+ page magazine article involving chemistry (must turn in article as well) Both due on Monday after Spring Break

4. Buffer Capacity How much acid/base can be neutralized by a buffer with 0.25 M CH 3 COOH and 0.25 M of CH 3 COO - in 1 L.

5. Sulfanilic acid, which is used in making dyes is made by reacting aniline with sulfuric acid. The acid has a pK a value of 3.23. The sodium salt of the acid is quite soluble in water. If you dissolve 1.25 g of the salt in 125 mL of solution, what is the pH of the solution?