Pts during the addition of naoh in part b which

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7. (3 pts) During the addition of NaOH in Part B , which buffer species reacted with the NaOH? Provide the balanced formula unit equation for this reaction.
PART B: Buffered Acetic Acid vs. NaOH (5 pts) Table 2 : Relevant volumes and pH readings during the NaOH titration of the buffer.
8. (3 pts) Based on the volume of NaOH added in Step 9 of the Data Analysis, determine the buffering capacity of the buffered acetic acid solution. You may disregard the volume of “1 L” from the definition and refer to the volume used of the original buffer. Be sure to include the correct units.
5 A. M. Bohnsack Fall 2018 (revised Z. Baranová)
Grading Rubric – Weak Acids and Buffers was 9.4 mL and then converted to 0.0094 liters. The NaOH added was then multiplied by the molarity which was 0.25 M and that gave a buffering capacity of 0.00235 moles of NaOH. 9. (6 pts) At volumes below the volume determined in Step 9 of the Data Analysis, discuss the relative changes in pH following subsequent NaOH additions. What happened to the pH following subsequent additions of NaOH after the Step 9 volume was reached? Why? Include the titration curve and second derivative curve from the Part B Data Analysis.
Graph 7: Titration Curve for Part B Buffered Acetic Acid vs. NaOH Graph 8: Second derivative curve for Part B Buffered Acetic Acid vs. NaOH 6 A. M. Bohnsack Fall 2018 (revised Z. Baranová)
Grading Rubric – Weak Acids and Buffers PART C: Buffered Acetic Acid vs. HCl (5 pts) Table 3 : Relevant volumes and pH readings during the HCl titration of the buffer. Titration Conditions HCl added (mL) pH Initial 0 mL 4.4 Buffering capacity reached 8.7 mL 3.6 Equivalence point 10.21 mL 3.36

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