Vallipurathanpalayam, Erode
PROJECT WORK
Subject : CHEMISTRY
Title of the Project : Comparative study of commercial antacids
Name of the Student : NIVEDHA K.P.
Board Roll Number :
Class & Section : XII-E
Academic Year : 2023-24
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Bonafide certificate
This is to certify that the CHEMISTRY project titled Comparative study
of commercial antacids is a Bonafide work carried out in CS ACADEMY,
ERODE during the academic year 2023-24 by NIVEDHA K.P. of Grade
XII-E, Reg No.
Subject teacher Principal
This project is submitted for All India Senior School Certificate Internal
Examination held on
Internal Examiner External Examiner
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ACKNOWLEDGEMENT
First and foremost, I would like to thank my School Director and the
Executive Director for having provided me with the facilities required
for my project. I extend my heartfelt thanks and profound gratitude to Mr
AmitKumar., Principal for his support during my project work.
It gives me great pleasure in expressing my gratification to
Mr.P.SathishKumar., Academic Coordinator for guiding us to
proceed forward.
I wholeheartedly express my deep sense of indebtedness and appreciation
to our teacher Mr.THIRUPAL REDDY (CHEMISTRY) for his
motivation, guidance and constant encouragement for the successful
completion of the task.
I extend my recognitions to all the faculty members of the Chemistry
department for their support during my project work.
Finally, an honorable mention goes to my family for their understanding
and provision throughout the process of completing the project.
With regards
NIVEDHA K.P.
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S.No Topics Page no.
1 Introduction 5
2 Objective 7
3 Theory 8
4 Experiment 15
5 Observation and Result 12
6 Conclusion 19
7 Bibliography 20
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INTRODUCTION
Gastric acid is a digestive fluid, formed in the stomach. It has a pH of
to 3.5 and is composed of 0.5 % hydrochloric acid (𝐻𝐶𝑙). It is produced by
cells lining the stomach, which are coupled to systems to increase acid
production when needed. There exists a mechanism present in the body to
maintain equilibrium in such cases. The stomach lining also contains
specialized cells called goblet cells that secrete mucus. The mucus forms a
protective layer on the stomach wall, preventing damage from the acidic
environment. Additionally, specialized cells called surface epithelial cells
secrete bicarbonate ions (𝐻𝐶𝑂3−) into the mucus layer, which helps to
neutralize any excessacid that might come into contact with the stomach
lining.
To counter this situation, substances like Antacids or literally anti - acids,
have been developed. Antacids are commercial products that neutralize the
excess acid in the stomach providing a sensation of relief to the person. The
action of antacids is based on the fact that a base can neutralize an acid
forming salt and water. Common antacids satisfy the condition – right
amount of alkali that can neutralize the acid. If the content of alkali in the
antacid is too high, no doubt acidity is relieved, but it’ll create alkaline
conditions that makes the digestive enzymes ineffective. To make sure that
the pH of the stomach remains in a specific range, many substances are
added to the antacids.
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OBJECTIVE
This project aims at analyzing some of the commercial antacids to
determine which one of them is the most effective by conducting a
quantitative analysis. Motives behind selecting this research project:
Consumerism, in the era of global industrialization, plays a very
important role. There are various product options available for
consumers to choose from. Different manufacturers selling their
products, attempting to sway public opinion in their favor, marketing
their products regardless of their effectiveness in functionality. Hence it
becomes the consumer’s right to experiment and know the most
effective, efficient, and value for money product. There are various
methods to conclude that a product out of all the given competitors is the
best. Experimental research is the most rational and convincing one of
those methods. The result of this analysis could be used to inform
oneself as to which antacid is the best and provides best relief.
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THEORY
Acid-Base Reaction:
Sodium hydroxide is a strong base, and when it comes into contact with
stomach acid (hydrochloric acid, 𝐻𝐶𝑙), an acid-base reaction occurs.
The hydroxide ions ( 𝑂𝐻− ) from sodium hydroxide react with the
hydrogen ions (𝐻∓) from hydrochloric acid.
𝑁𝑎𝑂𝐻 + 𝐻𝐶𝑙 → 𝑁𝑎𝐶𝑙 + 𝐻₂𝑂
In this reaction, sodium hydroxide ( 𝑁𝑎𝑂𝐻 ) and hydrochloric acid
(𝐻𝐶𝑙) combine to form sodium chloride (𝑁𝑎𝐶𝑙), also known as table
salt, and water (𝐻₂𝑂).
Neutralization:
The acid-base reaction between sodium hydroxide and hydrochloric
acid leads to neutralization. Sodium hydroxide, being a strong base,
accepts the hydrogen ions from the hydrochloric acid, effectively
neutralizing the acidic environment in the stomach.
𝑁𝑎𝑂𝐻 + 𝐻𝐶𝑙 → 𝑁𝑎𝐶𝑙 + 𝐻₂𝑂
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The sodium chloride formed (𝑁𝑎𝐶𝑙) is a salt that is easily dissolved in
the stomach fluid and does not contribute to acidity. During the
process, hydrogen ions from the acid (proton donor) or a hydronium
ion and hydroxide ions from the base (proton acceptor) react together to
form a water molecule. In the process, a salt is also formed when the
anion from acid and the cation from base react together. Neutralization
reactions are generally classified as exothermic since heat is released
into the surroundings. Acids are proton donors which convert into
conjugated bases. They are generally pure substances which contain
hydrogen ions or cause them to be produced in solutions. Hydrochloric
acid and sulfuric acid are common examples. In water, these break
apart into ions:
𝐻𝐶𝑙 + 𝐻2𝑂 ⇌ 𝐻3𝑂 + + 𝐶𝑙 −
𝐻2𝑆𝑂4 + 2𝐻2𝑂 ⇌ 2𝐻3𝑂 + + 𝑆𝑂4 2 −
Bases are proton acceptors which convert into conjugated acids. They
are generally substances which contain hydroxide ion or produce it in
solution. Alkalis are the soluble bases, i.e. a base which contains a
metal from group 1 or 2 of the periodic table. To produce hydroxide
ions in water, the alkali breaks apart into ions as below:
𝑁𝑎𝑂𝐻 ⇌ 𝑁𝑎+ + 𝑂𝐻−
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pH Increase:
By neutralizing the excess stomach acid, the pH level in the stomach is
increased. The pH scale measures the acidity or alkalinity of a
substance, with values below 7 being acidic, 7 being neutral, and values
above 7 being alkaline or basic. The introduction of sodium hydroxide
raises the pH in the stomach towards a more neutral or basic range,
reducing the acidity.
USES:
This medication is used to treat the symptoms of too much stomach
acid such as stomach upset, heartburn, and acid indigestion. It is also
used to relieve symptoms of extra gas such as belching, bloating, and
feelings of pressure/discomfort in the stomach/gut.
By neutralizing stomach acid, antacids relieve symptoms such as
burning behind the breast bone or throat area (oesophagus) caused by
acid reflux, a bitter taste in the mouth, a persistent dry cough, pain
when lying down, or regurgitation. Some antacids are also used for
completely unrelated medical conditions, for example:
Aluminum antacids: lower elevated blood phosphate levels and
prevent the formation of kidney stones.
Calcium carbonate antacids: treat calcium deficiency
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Magnesium oxide antacids: treat magnesium deficiency
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EXPERIMENT
REQUIRMENTS:
A. Apparatus:
1. Burettes
2. Pipettes
3. Titration Flasks
4. Measuring Flasks
5. Beakers
6. Weight box
7. Filter Paper
8. Fractional weights
B. Chemicals:
1. Sodium Hydroxide(𝑁𝑎𝑂𝐻)
2. Sodium Carbonate(𝑁𝑎2𝐶𝑂3)
3. Hydrochloric acid(𝐻𝐶𝑙)
4. Phenolphthalein
5. Methyl Orange
6. Samples of Antacids
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PROCEDURE:
1. First prepare 1 litre of approximately N/10 solution of 𝐻𝐶𝑙 by
diluting 10ml of the given 10𝑀 𝐻𝐶𝑙 acid to 1litre.
2. Next prepare 1litre of approx. N/10 𝑁𝑎𝑂𝐻 solution by dissolving
4.0g of 𝑁𝑎𝑂𝐻 to make1litre of solution.
3. Similarly prepare N/10 𝑁𝑎2𝐶𝑂3 solution by weighing exactly
1.325g of anhydrous 𝑁𝑎2𝐶𝑂3 and then dissolving it in water to
prepare exactly 0.25L or 250 ml of 𝑁𝑎2𝐶𝑂3 solution.
4. Now, standardize the 𝐻𝐶𝑙 solution by titrating it against the
standard 𝑁𝑎2 𝐶𝑂3 solution using methyl orange as indicator.
5. Similarly standardize the 𝑁𝑎𝑂𝐻 solution by titrating it against
standardized 𝐻𝐶𝑙 solution using phenolphthalein as indicator. Stop
the titration when the pink color of the solution disappears.
6. Now, powder the four antacid samples and weigh 0.5 g of each.
7. Add 25 ml of the standardized 𝐻𝐶𝑙 to each of the weighed samples
taken in conical flasks. Make sure that the acid is in slight excess
so that it neutralize all the basic character of the tablet powder.
8. Add a few drops of phenolphthalein indicator and warm the flask
over a bunsen burner till most of the powder dissolves.
9. Filter the insoluble material. Titrate this solution against the
standardized 𝑁𝑎𝑂𝐻 solution till a permanent pinkish tinge is
obtained.Repeat the same experiment for all other samples too.
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PRECAUTIONS:
1. Avoid touching the antacid with your fingers.
2. Be careful not to lose any solid when crushing the antacid tablet.
3. Avoid touching hot surfaces when working near the hot plate and
be cautious when transporting heated solutions.
4. The hot plate should not be left unattended.
5. Dilute 𝐻𝐶𝑙 and 𝑁𝑎𝑂𝐻 were corrosive and can damage your eyes
and cause skin irritation.
6. The burette must be rinsed out with 𝑁𝑎𝑂𝐻 before use to prevent
dilution of the solution.
7. It should be made sure that there were no air bubbles in the burette
tips.
8. Burette readings should be recorded to the nearest 0.05 cm3.
9. Sodium hydroxide should be removed from the burette as soon as
possible after the titration. It was because 𝑁𝑎𝑂𝐻 is corrosive and it
reacted with carbon dioxide in the air to form sodium carbonate
which was a white solid and clogged the tip of the burette easily.
10. Rinse all apparatus thoroughly using Distilled water. Any residual
chemicals could cause variations in pH readings
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OBSERVATION AND RESULT
OBSERVATION:
➢ Standardization of HCl solution:
Volume of 0.1N 𝑁𝑎2𝐶𝑂3 taken = 20 ml
Indicator used = Methyl Orange
SERIAL BURETTE READINGS VOLUME
No. OF ACID
INITIAL READING FINAL READING USED (ml)
1. 0 17 17
2. 18 35 17
Applying normality equation,
𝑁1 𝑉1 = 𝑁2 𝑉2
(𝑎𝑐𝑖𝑑) (𝑏𝑎𝑠𝑒)
𝑁1 × 17 = 0.1 × 20
Normality of HCl,
2
𝑁1 = = 0.11 ≈ 0.1
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➢ Standardization of NaOH Solution:
Volume of the given 𝑁𝑎𝑂𝐻 solution taken = 20.0 ml
Indicator used = Phenolphthalein
SERIAL BURETTE READINGS VOLUME
No. OF ACID
INITIAL READING FINAL READING USED (ml)
1. 0 16 16
2. 17 33 16
Volume of acid used = 16 ml
Applying normality equation,
𝑁1 𝑉’1 = 𝑁’2 𝑉’2
(acid) (base)
0.11 × 16 = 𝑁’2 × 20
Normality of HCl,
(0.11 × 16)
𝑁’2 = = 0.09 ≈ 0.1
20
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➢ Analysis of antacid tablets:
• Weight of the antacid tablet powder = 0.5 g
• Volume of 𝐻𝐶𝑙 solution added = 30 ml
• Volume of sample solution taken = 20 ml
for titration
VOLUME OF (𝑵𝒂𝑶𝑯)
USED FOR
ANTACID
NEUTRALIZING
UNUSED (𝑯𝑪𝑳)
1. Eno Pineapple 29
2. Eno Lemon 24
3.Digene Lime 9
4.Omez 24
5. Pephyrous 40
6. Gelusil 22
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RESULT:
• 1g of Eno Pineapple required 29 ml of Sodium Hydroxide (𝑁𝑎𝑂𝐻)
to titrate it completely.
• 1 g of Eno Lemon required 24 ml of Sodium Hydroxide (𝑁𝑎𝑂𝐻)
solution to titrate it completely.
• 1 g of Digene lime required 9 ml of Sodium Hydroxide (𝑁𝑎𝑂𝐻) to
titrate it.
• 1 g of Omez required 24 ml of Sodium Hydroxide (𝑁𝑎𝑂𝐻) to
titrate it completely.
• 1 g of Pephyrous required 40 ml of Sodium Hydroxide (𝑁𝑎𝑂𝐻) to
titrate it completely.
• 1 g of Gelusil required 22 ml of Sodium Hydroxide (𝑁𝑎𝑂𝐻) to
titrate it completely.
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CONCLUSION
Antacids play a very important role in relieving many patients suffering
from gastric hyperacidity, commonly referred to as gastritis. This project
was undertaken to analyze the best commercially available antacid
according to the amount of hydrochloric acid they could neutralize.
After exploring many books and websites to find out more about
antacids, we were clear of its role and its applications. Various antacids
could neutralize a specific amount of the acid.
• Pephyrous was the poorest among all antacids.
• Eno pineapple had a slightly higher alkaline nature while Eno
lemon and Omez proved to neutralize to same amount. Gelusil
had a higher concentration of the base.
Digene had the highest basic character. Thus, on the basis of the
experiment conducted, it was adjudged that Digene was the best
commercially available antacid.
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BIBLIOGRAPHY
1. https://www.slideshare.net/vinayleokumar/chemistry-
investigatory-project-on-antacids
2. http://www.reachoutmichigan.org/funexperiments/quick/csustan/
antacid
3. http://ien2.uneche.maine.edu/genchemlabs/Antacid /antacid2
4. http://www.pharmaceutical-drug-manufacturers.com
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