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16.116 You can measure the pH in the Acids and Bases simulation (eChapter 16.4) for aqueous solutions of 13 different compounds. (a) List the compounds available in the simulation, and identify each as a strong acid, a weak acid, a strong base, or a weak base. (b) For each compound, measure and record the pH of a 0.05 M solution.

16.117 (a) Using data from the Acids and Bases simulation (eChapter 16.4), calculate the K_a of HNO₂. (b) Determine the percent ionization of HNO₂ at 2.0 M, 0.20 M, 0.020 M, and 0.0020 M concentrations. (c) Explain the trend in percent ionization using Le Châtelier's principle.

16.118 The Introduction to Aqueous Acids animation (eChapter 16.5) illustrates the ionization in water of two different strong acids and one weak acid. (a) Given that all three ionize to produce hydrogen ion in water, what is it about the behavior of the weak acid that makes it different from the strong acids? (b) What is the consequence of this difference in terms of pH?

16.119 The Introduction to Aqueous Bases animation (eChapter 16.5) illustrates the ionization of a weak base. (a) Write the equation that corresponds to the ionization of ammonia in water. (b) In the animation the ammonia molecule ionizes, producing aqueous hydroxide. What is it about the behavior of ammonia in water that makes ammonia a weak base?

16.120 The K_b of ammonia is 1.8 x 10^-5. (a) Calculate the concentration of aqueous ammonia that would have a pH of 8.5. Use the Acids and Bases simulation (eChapter 16.4) to check your answer. (b) What is the percent ionization of ammonia at this concentration?

16.121 Use the Equilibrium Constant simulation (eChapter 16.6) to experiment with the ionization of a weak acid. Choose the HA H⁺ + A^- reaction, and enter the K_a of acetic acid (1.8 x 10^-5). (a) Enter a starting HA concentration of 0.1 M, and determine the equilibrium concentration of H⁺ (b) By what percentage did the concentration of HA change? (c) By what percentage did the concentration of H⁺ change? (d) Calculate pH and pOH of the 0.1 M solution of acetic acid.