2. The pKa of acetic acid is 4.76. Calculate the expected pH of each of the solutions (tubes 1-5) before and after addition of 1.0mL of HCl. Hints: Remember HCl is a strong acid, Ka=[H+][A]/[HA], I(nitial) C(hange) E(quilibrium) tables are useful, and the assumption you can use to solve equilibrium problems, especially to use the HendersonHasselbalch equation. Also, for repetitive calculations, using an Excel Spreadsheet (or a similar program) is highly encouraged. In that case, show a sample calculation and upload your Excel file with your pre-lab assignment (multiple files can be up loaded). Whether you use a spreadsheet or not, tabulate your results in your pre-lab assignment. Please remember significant figures. 3. Calculate the pH of the solution in tube 6 in Part II after the addition of HCl. 4. Do your answers in questions 2 and 3 make sense in terms of what you know about buffers? Concisely explain why or why not. Included in your answer should be which buffer works best at resisting pH changes and which you would predict would be the worst. Part II: Buffer Capacity of Acetate Buffers Obtain 6 clean, dry 15mL tubes. Label the tubes and prepare the buffers according to the table below. **Use pipets for all volume measurements* Cover each tube with parafilm, mix by inversion, measure the pH and record in your notebook. To each tube, add 1.0mL of 0.1MHCl. Mix well, measure the pH again and record in your notebook