ApchemWiki | RecentChanges | Preferences
Answer the following questions on a separate section in your lab notebook.
1. Explain the proper way of cleaning a buret to be used in a titration.
2. For each titration you performed:
2a. On the graph of the pH curve, draw dotted lines to show what the pH is at the equivalence point (all trials) and the half-way point (only for weak acid/base).
2b. Using your graph information, determine the Ka / Kb of the weak acid/base.
2c. Using your lab information, calculate the theoretical pH at the equivalence point.
3. On the pH curve of the strong acid and base, draw (in pencil) the pH curve of two weak acid and two weak base:
3a. You will calculate the pH of the initial weak acid/base solution (before titration) assuming that the concentration are the same as the strong acid/base.
3b. The second point you calculated will be at the half-way point.
3c. The rest of the pH curve you will guesstimate using your knowledge of pH curves.
3d. Use the acid ionization and base dissociation equilibrium constant values from the chapter of AP book or at end of AP book.
4. After you make your updated pH curves of weak and strong acids, where there are areas that were common to strong and weak acids?
5. Using each the weak acid or weak base pH curves, separate the curves into 3 distinct areas and explain what are the main species in the bucket at each point and how does that explain the calculation you are doing to determine the pH/pOH of the solution.