Information Stock acetic acid concentration: 1.0184 mol/L Stock sodium acetate concentration: 1.0166 mol/L pKa of acetic acid = 4.75   a) Calculate the pH of the stock acetic acid solution and the pH of the stock sodium acetate solution b) Calculate the pH of the undiluted buffer c) Calculate the pH of the 50% buffer *The file included explains how the buffers were prepared

Chemistry
10th Edition
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
icon
Related questions
Question

Information

Stock acetic acid concentration: 1.0184 mol/L

Stock sodium acetate concentration: 1.0166 mol/L

pKa of acetic acid = 4.75

 

a) Calculate the pH of the stock acetic acid solution and the pH of the stock sodium acetate solution

b) Calculate the pH of the undiluted buffer

c) Calculate the pH of the 50% buffer

*The file included explains how the buffers were prepared

Part C: Preparation and Dilution of a Buffer
Use a graduated cylinder to measure volumes.
• Obtain 100 mL of 1 M acetic acid and 100 mL of 1 M sodium acetate solutions from the stock
bottles. Record the actual concentrations of these solutions as indicated on the stock bottles.
Measure the pH of these two solutions using the pH meter.
Prepare a buffer solution by mixing 100 mL 1 M acetic acid with 100 mL 1 M sodium acetate
solution. Stir.
Prepare a 50% buffer solution by adding 100 mL of this buffer to 100 mL deionized water;
stir.
Prepare a 25% buffer solution by adding 100 mL of 50% buffer to 100 mL deionized water;
stir.
• Measure the pH of the 3 buffer solutions. Save buffer solutions for next part.
Addition of strong base to buffered and unbuffered solutions:
• Clean the burette used in part A/B, rinse and then fill with 3 M NaOH
• With a graduated cylinder, measure 75 mL of the original buffer solution into a 200 mL
Berzelius beaker and place the magnetic stir bar in this solution. Set up your burette, stirrer
and pH probe as in part A/B. Using the burette, add ~1 mL of 3 M NaOH to the buffer, read
and record the pH. Continue adding base in 1 mL increments until 15 mL of NaOH has been
added. Record the pH after each 1 mL addition of NaOH.
Repeat the addition of NaOH in the same manner, using 75 mL of the 50% buffer. Record
the pH after every 1 mL addition until a total of 15 mL of NaOH has been added.
Repeat the addition of NaOH in the same manner, using 75 mL of the 25% buffer. Record
the pH after every 1 mL addition until a total of 15 mL of NaOH has been added.
• Repeat the addition of NaOH in the same manner, using 75 mL of deionized water.
Record the pH after every 1 mL addition until a total of 15 mL of NaOH has been added.
Transcribed Image Text:Part C: Preparation and Dilution of a Buffer Use a graduated cylinder to measure volumes. • Obtain 100 mL of 1 M acetic acid and 100 mL of 1 M sodium acetate solutions from the stock bottles. Record the actual concentrations of these solutions as indicated on the stock bottles. Measure the pH of these two solutions using the pH meter. Prepare a buffer solution by mixing 100 mL 1 M acetic acid with 100 mL 1 M sodium acetate solution. Stir. Prepare a 50% buffer solution by adding 100 mL of this buffer to 100 mL deionized water; stir. Prepare a 25% buffer solution by adding 100 mL of 50% buffer to 100 mL deionized water; stir. • Measure the pH of the 3 buffer solutions. Save buffer solutions for next part. Addition of strong base to buffered and unbuffered solutions: • Clean the burette used in part A/B, rinse and then fill with 3 M NaOH • With a graduated cylinder, measure 75 mL of the original buffer solution into a 200 mL Berzelius beaker and place the magnetic stir bar in this solution. Set up your burette, stirrer and pH probe as in part A/B. Using the burette, add ~1 mL of 3 M NaOH to the buffer, read and record the pH. Continue adding base in 1 mL increments until 15 mL of NaOH has been added. Record the pH after each 1 mL addition of NaOH. Repeat the addition of NaOH in the same manner, using 75 mL of the 50% buffer. Record the pH after every 1 mL addition until a total of 15 mL of NaOH has been added. Repeat the addition of NaOH in the same manner, using 75 mL of the 25% buffer. Record the pH after every 1 mL addition until a total of 15 mL of NaOH has been added. • Repeat the addition of NaOH in the same manner, using 75 mL of deionized water. Record the pH after every 1 mL addition until a total of 15 mL of NaOH has been added.
Expert Solution
steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Acid-Base Titrations
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Chemistry
Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning
Chemistry
Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education
Principles of Instrumental Analysis
Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning
Organic Chemistry
Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education
Chemistry: Principles and Reactions
Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning
Elementary Principles of Chemical Processes, Bind…
Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY