ACKNOWLEDGEMENT
It would be my utmost pleasure to express my
sincere thanks to my chemistry teachers and my
parents in providing a helping hand in this project.
Their valuable guidance, support and supervision
all through this project titled “DETERMINATION
OF THE CONTENTS OF COLD DRINKS” are
responsible for the attaining its present form.
Snehangshu Roy
Class XI
PURPOSE
In recent days, soft drink brands were put into
various questions regarding their purity. News
flashed that they contain harmful pesticides which
arouse mainly the interest in knowing its contents
because I have been drinking them for years. I
wanted to confirm that whether the charge
imposed upon these brands are tire or not.
Another fact which inspired me to do this project
is that I am in touch with qualitative analysis
whose knowledge with other factors helped me to
do so.
AIM:
COMPARATIVE STUDY AND
QUANTITATIVE ANALYSIS OF
DIFFERENT BRANDS OF
COMMERCIALLY AVAILABLE
COLD DRINKS
CONTENTS
● Introduction
● Theory
● Apparatus
● Chemical Required
● Detection of pH
● Test for Carbon Dioxide
● Test for Glucose
● Test for Phosphate
● Result
● Conclusion
INTRODUCTION
The era of cold drinks began in 1952 but the
industrialization in India marked its beginning
with launching of Limca and Goldspot by
parley group of companies. Since, the
beginning of cold drinks was highly profitable
and luring, many multinational companies
launched their brands in India like Pepsi and
Coke. Nowadays, it is observed in general that
majority of people viewed Sprite, Miranda and
Limca to give feeling of lightness while Pepsi
and Thumbs to activate pulse and brain.
THEORY
Cold drinks of different brands are composed
of alcohol, carbohydrates, carbon dioxide,
phosphate ions etc. These soft drinks give
feeling od warmth, lightness and have a tangy
taste which is liked by everyone. Carbon
dioxide is responsible for the formation of
forth on shaking the bottle.
The carbon dioxide gas is dissolved in water to
form carbonic acid which is also responsible
for the tangy taste. Carbohydrates are the
naturally occurring organic compound and are
major source of energy to our body. General
formula of carbohydrates is Cx(H2O)y. On the
basis of their molecular size carbohydrates are
classified as – Monosaccharide, Disaccharides
and Polysaccharides. Glucose is a
monosaccharide with formula C6H12O6. It
occurs in the free state in ripen grapes bones
and also in many sweet fruits. It is also present
in human blood to the extent of about 0.1%.
Sucrose is one of the most useful
disaccharides in our daily life. It is widely
distributed in nature in juices, seeds and also
in flowers of many plants. The main source of
sucrose is sugar can juice which contain
15-20% sucrose and sugar beet which has
about 10-17% sucrose. The molecular formula
of sucrose is C12H22O11. It is produced by a
mixture of glucose and fructose. It is
non-reducing in nature whereas glucose is
reducing. Cold drinks are bit acidic in nature
and their acidity can be measured by finding
their pH value. The pH values also depend
upon their acidic contents such as citric acid
and phosphoric acid.
APPARATUS
● Test Tube
● Test tube holder
● Test tube stand
● Stop Watch
● Beaker
● Burner
● pH Paper
● Tripod stand
● China Dish
● Wire Gauge
● Water Bath
CHEMICALS REQUIRED
● Fehling’s A & B Solution
● Lime Water
● Concentrated HNO3
● Benedict Solution
● Ammonium Molybdate
DETECTION OF pH
Small samples of clod drinks of different brands
were taken in a test tube and put on the pH paper.
The change in the color of pH paper was noticed
and was compared with the standard pH scale.
Sl.No Drink Color pH
1 Coca Cola Pink 2.5-3
2 Sprite Red 3
3 Limca Pinkish 4
4 Fanta Light 3-4
Orange
INFERENCE
Soft drinks are generally acidic because of the
presence of citric acid and phosphoric acid. pH
values of cold drink of different brands are
different due to the variation in amount of acidic
contents.
TEST FOR CARBON DIOXIDE
As soon as the bottles were opened, one by one
the sample was passed through lime water. The
lime water turned milky.
Time for Milkiness to appear:
Coca-Cola: 26 seconds
Sprite: 21 seconds
Limca: 35 seconds
Fanta: 36 seconds
INFERENCE
All the soft drinks contain dissolved carbon dioxide
in water. The carbon dioxide dissolves in water to
form carbonic acid, which is responsible for its
tangy taste.
CHEMICAL REACTIONS INVOLVED
Ca(OH)2(s) + CO2(g) ----------> CaCO3(s) + H2O(s)
TEST FOR GLUCOSE
Glucose is a reducing sugar acid. Its presence is
detected by the following test:
1.BENEDICTS’S REAGENT TEST:
Small samples of cold drinks of different
brands were taken in a test tube and a few
drops of Benedict’s reagent were added. The
test tube was heated for few seconds
formation of reddish color confirmed the
presence of glucose in cold drinks. All the
drinks viz Sprite, Fanta, Limca and Coca-Cola
gave a positive test.
2.FEHLING’S SOLUTION TEST:
Small samples of cold drinks of different
brands were taken in a test tube and a few
drops of Fehling’s A solution and Fehling’s B
solution was added in equal amount. The test
tube was heated in a water bath for 10
minutes. Appearance of brown precipitate
confirmed the presence of glucose in cold
drinks. Again, all drinks tested Positive.
INFERENCE:
Positive tests indicate the presence of glucose
in all the soft drinks.
TEST FOR PHOSPHATE
Small samples of each brand of cold drinks were
taken in separate test tubes and Ammonium
Molybdate followed by concentrated Nitric Acid
was added to it. The solution was heated.
Appearance of canary-yellow precipitate
confirmed the presence of phosphate ions in cold
drinks.
All the soft drinks, viz Sprite, Coca-Cola, Fanta and
Limca gave a positive test for phosphate ions.
INFERENCE:
All the cold drinks contained phosphate ions in
solution.
CHEMICAL REACTION INVOLVED
NaHPO4 + 12(NH4)2MoO4 + 21HNO3 + 3H ------>
(NH4)3PO4.12MoO3+21NH4NO3 +12H2O
The yellow ppt is known as ammonium
phosphomolybdate.
CONCLUSION
DISADVANTAGES OF COLD DRINKS:
1.Soft drinks are little more harmful than sugar
solution. As they contain sugar in large
amount which cause problems in diabetes
patients.
2.Soft drinks can cause weight gain as they
interfere with the body’s natural ability to
suppress hunger feeling.
3.Soft drinks have ability to dissolve the calcium
so they are also harmful for our bones.
4.Soft drinks contain “phosphoric acid” which
has a pH of 2.8. So they can dissolve a nail in
about 4 days.
5.For transportation of soft drinks syrup the
commercial truck must use the hazardous
matter place cards reserved for high consive
material.
6.Soft drinks have also ability to remove blood
so they are very harmful to our body.
USES OF COLD DRINKS:
1.Cold drinks can be used as toilet cleaner.
2.They can remove rust spots from chrome
car humpers
3.They clean corrosion from car battery
terminals.
4.Soft drinks are used as an excellent
detergent.
BIBLIOGRAPHY
Following books and websites were sources of my
project.
1.QUALITATIVE ANALYSIS BY VOGEL
2.ORGANIC CHEMISTRY – MORRISON AND BOYD
3.Comprehensive Chemistry Lab Manual
4.www.google.com
5.www.wikipedia.com
6.www.lcbse.com
7.www.unoregon.edu
TEACHER’S REMARKS:
