B calculate the pk a pk a log k a pk a 5 pk a 474 c

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b.) Calculate the pK a :
c.) Calculate the pH:
6. (2 pts) What was the measured pH of the buffer solution prior to the addition of NaOH? Use the theoretical pH calculated in Discussion Question 5 and the following equation to determine and discuss the % error of your results: 13 A. M. Bohnsack Spring 2019 (revised Z. Baranová)
Worksheet & Grading Rubric – Weak Acids and Buffers
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. 14 A. M. Bohnsack Spring 2019 (revised Z. Baranová)
Worksheet & Grading Rubric – Weak Acids and Buffers
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.
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