Upload
others
View
7
Download
0
Embed Size (px)
Citation preview
Vinegar Titration 😊Name:______________________________ PURPOSE: To determine the percentage and concentration of acetic acid in vinegar.
MATERIALS:
Burette Retort stand Burette Clamp Erlenmeyer Flask Gloves
Funnel Phenolphthalein Graduated pipette Pi pump Waste container
Safety glasses 1.0M NaOH Vinegar Beaker Paper towels
PROCEDURE:
Part 1: Setting up apparatus
1) Rinse the burette and graduated pipette with water several times
2) Attach the burette to the clamp, insert the funnel into the burette and make sure that the
stopcock is closed.
3) Put on all necessary safety equipment
4) Pour sodium hydroxide into the beaker
5) Pour sodium hydroxide from the beaker into the burette. Get as close to the zero mark as
possible
6) Pour any remaining sodium hydroxide back into the flask, and stopper the flask
7) Using the graduated pipette and pi pump, pour 25 mL of vinegar into the erlenmeyer flask
8) Add 3 drops of phenolphthalein to the vinegar in the erlenmeyer flask
9) Place the Erlenmeyer flask under the burette so that the tip of the burette is just inside
the Erlenmeyer flask.
Part 2: Raw Titration
1) Record the initial volume of the burette
2) Open the stopcock so that a thin stream of sodium hydroxide flows out
3) Swirl the flask continuously as the sodium hydroxide is flowing into the vinegar
4) Once the solution turns and stays light pink, close the stopcock
5) Record the volume of sodium hydroxide used
6) Pour the vinegar solution into the waste container
Part 3: Titration
1) Refill the buret with sodium hydroxide like in part 1, steps 4 to 7
2) Fill the flask with 25 ml vinegar, like in part 1, steps 8 to 9
3) Place the flask under the burette so that the tip of the burette is just inside the flask
4) Open the stopcock so that the sodium hydroxide drips into the vinegar
5) Swirl the flask with vinegar as the sodium hydroxide is dripping into it
6) As soon as the pink color appears and stays, close the stopcock. The final state of the
solution should be light pink.
7) Record the volume of sodium hydroxide used
8) Pour vinegar solution into the waste container
9) Repeat steps 1 to 8 a total of 3 times
OBSERVATIONS:
Trial Raw 1 2 3
Volume of Vinegar
Volume of NaOH:
Initial reading
Volume of NaOH:
Final reading
Volume of NaOH used:
Final - Initial
SOURCES OF ERROR:
Along with your list of errors, answer the question below:
1) How would not clearing an air bubble from the tip of a burette
ANALYSIS:
1) Calculate the average volume of NaOH used (do not include raw data) (1 mark)
2) How many moles of NaOH is this? (1 mark)
3) Write the neutralization reaction for vinegar (2 marks)
4) How many moles of vinegar is neutralized? (2 mark)
5) What is the concentration of the vinegar (1 mark)
6) Calculate the %v/v for the vinegar (1 mark)
7) Write the total ionic equation for the neutralization of vinegar (2 marks)
CONCLUSION:
The concentration of vinegar in your sample was 5% v/v.
1) How does this compare to your finding
2) Why is this different from the value that you calculated? If you did get 5% v/v, which is
unlikely, what did you do to make your experimental value so precise?
DIVISION OF LABOUR
Part 1 Name:_______________________
● Separate Title Page: 1 mark
● Testable Question: 1 mark
● Materials: 1 mark
● Procedure: 5 marks
● Conclusion: 2 marks
Part 2 Name: _______________________
Test Design for the procedure
● Part 1: 5 marks
● Part 2: 2 marks
● Part 3: 3 marks
Part 3 Name: _______________________
● Observations: 5 marks
● Sources of Error: 5 marks
○ Detailed Errors List: 3 marks
○ Question 1: 2 marks
Part 4 Name: ______________________
Analysis
Questions 1 to 7, 10 marks total