R.
N PODAR SCHOOL
CHEMISTRY PROJECT
Measuring the Amount of Acetic Acid in Vinegar
Name: Samyak Oswal
Class: XII A
Board Roll no:
CERTIFICATE
This is to certify that Samyak Oswal of standard XII has
completed the Chemistry project in partial fulfilment of
the curriculum of ALL INDIA SENIOR SECONDARY
CERTIFICATE EXAMINATION (AISSCE). This
project was carried out at R.N. PODAR SCHOOL
laboratory during the academic year 2022-23.
ACKNOWLEDGEMENT
I would like to express my deepest regards to the
principal, Mrs. Avnita Bir, for providing us with the
infrastructure and facilities for the project.
I would further like to extend my thanks to my
chemistry teacher Ms. Meeta Pathak under whose
guidance this project was performed. Her constant
support and invaluable guidance helped me to achieve
completion of this project.
I also want to express my gratitude to the Chemistry
Department of the school and Chemistry laboratory
incharge, Neha ma’am.
Last but not the least, I want to thank my family for
their moral support.
INDEX
1. Aim
2. Introduction
3. Theory
4. Material Requirements
5. Procedure
6. Observations and calculations
7. Result
8. Precautions
9. Bibliography
AIM
To measure the amount of acetic acid in 3 different
kinds of vinegar.
INTRODUCTION
Vinegar is a solution made from the fermentation of ethanol
(CH3CH2OH), which in turn was previously fermented from sugar.
The fermentation of ethanol results in the production of acetic acid
(CH3COOH).
There are many different types of vinegar, each starting from a
different original sugar source (e.g., rice, wine, malt, etc.). The
amount of acetic acid in vinegar can vary, typically between 4 to 6%
for table vinegar, but up to three times higher (18%) for pickling
vinegar.
In this project, we will determine the amount of acid in different
vinegars using titration, a common technique in chemistry.
THEORY
Titration is a way to measure the unknown amount of a chemical in a
solution (the titrant) by adding a measured amount of a chemical
with a known concentration (the titrating solution). The titrating
solution reacts with the titrant, and the endpoint of the reaction is
monitored in some way. The concentration of the titrant can now be
calculated from the amount of titrating solution added, and the ratio
of the two chemicals in the chemical equation for the reaction.
To measure the acidity of a vinegar solution, we can add enough
hydroxyl ions to balance out the added hydrogen ions from the acid.
The hydroxyl ions will react with the hydrogen ions to produce
water. In order for a titration to work, we need three things: a
titration solution (contains hydroxyl ions with a precisely known
concentration), a method for delivering a precisely measured volume
of the titrating solution, and a means of indicating when the endpoint
has been reached.
For the titrating solution, we’ll use a solution of sodium hydroxide
(NaOH). Sodium hydroxide is a strong base, which means that it
dissociates almost completely in water. So for every NaOH molecule
that we add to the solution,we can expect to produce a hydroxyl ion.
To dispense an accurately measured volume of the titrating solution,
we will use a burette. A burette is a long tube with a valve at the
bottom and graduated markings on the outside to measure the
volume contained in the burette. The burette is mounted on a ring
stand, directly above the titrant solution. The surface of the liquid in
the burette forms a curve called a meniscus. To measure the volume
of the liquid in the burette we read from the bottom of the meniscus.
In this experiment, we will use an indicator solution called
phenolphthalein. Phenolphthalein is colourless when the solution is
acidic or neutral. When the solution becomes slightly basic,
phenolphthalein turns pinkish, and then light purple as the solution
becomes more basic. So when the vinegar solution starts to turn
pink, we know that the titration is complete.
MATERIALS REQUIRED
Apparatus: 125 mL conical flask, 25 mL burette,
ring stand, burette clamp, 10 ml pipette
Chemicals: 4 M NaOH, phenolphthalein, Apple
cider vinegar, chilli vinegar, glacial acetic acid
PROCEDURE
Pour 10 ml of vinegar in a conical flask using a pipette.
Add distilled water to dissolve the vinegar so that the volume of the
solution becomes 20 mL.
Add 3 drops of phenolphthalein solution.
Use the burette clamp to attach the burette to the ring stand. The
opening at the bottom of the burette should be just above the height
of the Conical flask we use for the vinegar and phenolphthalein
solution.
Use a funnel to fill the burette with a 4 M solution of sodium
hydroxide up to the 0ml mark.
Put the vinegar solution to be titrated under the burette
Slowly drip the solution of sodium hydroxide into the vinegar
solution. Swirl the flask gently to mix the solution, while keeping
the opening underneath the burette.
At some point we will see a pink colour in the vinegar solution when
the sodium hydroxide is added, but the colour will quickly disappear
as the solution is mixed. When this happens, slow the burette to
drop-by-drop addition.
When the vinegar solution turns pink and remains that colour even
with mixing, the titration is complete. Close the tap (or pinch valve)
of the burette.
Note the level of the sodium hydroxide solution in the burette.
For each vinegar that we test, repeat the titration at least three times.
Adding phenolphthalein to conical
flask
End point of titration- light pink
coloured solution
OBSERVATIONS AND
CALCULATIONS
EXPERIMENT 1: Apple cider vinegar
S.no Volume of vinegar(in Volume of NaOH
ml) used(in ml)
1. 10ml 4.9
2. 10ml 5.1
3. 10ml 5.1
Final volume of NaOH=5.1ml
Calculations:
We know that
Molarity of vinegar * volume of vinegar = Molarity of NaOH * volume of
NaOH
Molarity of vinegar=x
Volume of vinegar=10ml
Molarity of NaOH=4
Volume of NaOH=5.1ml
So, x*10=4*5.1
Therefore,
x=2.04 moles/litres
Molar mass of acetic acid=60g
Strength = molarity* molar mass
= 2.04*60
Strength=122.4 gram/litres
Burette reading of 5.1ml
EXPERIMENT 2: Chilli vinegar
S.no Volume of vinegar(in Volume of NaOH
ml) used(in ml)
1. 10ml 2.8
2. 10ml 2.6
3. 10ml 2.6
Final volume of NaOH= 2.6ml
Calculations:
Molarity of vinegar=x
Volume of vinegar=10ml
Molarity of NaOH=4
Volume of NaOH=2.6ml
So, x*10=4*2.6
Therefore,
x=1.04 moles/litre
Molar mass of acetic acid=60g
Strength = molarity* molar mass
= 1.04*60
Strength=62.4 gram/litres Burette reading 2.6ml
EXPERIMENT 3: Glacial acetic acid
S.no Volume of vinegar(in Volume of NaOH
ml) used(in ml)
1. 10ml 14.3
2. 10ml 14.1
3. 10ml 14.1
Final volume of NaOH=14.1ml
Calculations:
Molarity of vinegar=x
Volume of vinegar=10m
Molarity of NaOH=4
Volume of NaOH=14.1ml
So, x*10=4*14.1
Therefore,
x=5.64 moles/litre
Molar mass of acetic acid=60g
Strength = molarity* molar mass
= 5.64*60
Burette reading of 14.1ml
Strength=338.4 gram/litres
RESULT
Strength of apple cider vinegar = 122.4 g/L.
Strength of chili vinegar = 62.4 g/L.
Strength of glacial acetic acid = 338.4 g/L.
Therefore, order of amount of acetic acid in different
kinds of vinegars is:
Glacial acetic acid> Apple cider vinegar> Chili vinegar
PRECAUTIONS
Transference of measured vinegar into a measuring
flask should be done very carefully.
Measuring must be performed carefully.
Look at the meniscus of solution at eye level to
avoid parallax.
Look at the lower meniscus in the light coloured
solution and upper meniscus in the dark coloured
solution because of visibility.
Do not forget to add distilled water to the vinegar.
BIBLIOGRAPHY
https://www.icbse.com/projects/chemistry-project-
to-measure-the-amount-of-acetic-acid-in-vinegar-
y34#:~:text=Pour%201.5%20ml%20of%20vinegar
,burette%20to%20the%20ring%20stand.
https://chem.libretexts.org/Ancillary_Materials/Lab
oratory_Experiments/Wet_Lab_Experiments/Gener
al_Chemistry_Labs/Online_Chemistry_Lab_Manu
al/Chem_10_Experiments/11%3A_Titration_of_Vi
negar_(Experiment)
https://schoolworkhelper.net/titration-of-vinegar-
lab-answers/
