- The student conducted an experiment to quantify the amount of caffeine in different tea samples. - Through extraction with petroleum ether, they determined that Ripple tea contained 0.55mg of caffeine while Tetley Green tea contained 0.30mg, showing Ripple tea had a higher caffeine content. - The aim was to perform a quantitative analysis of the presence of caffeine in various tea samples through a extraction and weighing procedure under a teacher's guidance for a school chemistry examination.

1. CHEMISTRY
INVESTIGATORY PROJECT
AIM: QUANTITATIVE ANALYSIS OF
PRESENSE OF CAFFEINE IN DIFFERENT
TEA SAMPLES

2. KENDRIYAVIDYALAYA NO.2
KATARI BAGH, KOCHI-04DEPARTMENTOF
CHEMISTRY
CERTIFICATE
This is to certify that VIMAL KUMAR, a student of class XII-B has
successfully completed the research on the project carried out in the
chemistry lab under the guidance of Mrs. Biji Kuriakose (PGT Chemistry)
during the year 2016-17 in partial fulfillment of chemistry practical
examination conducted by AISSCE, New Delhi.
Signature of Chemistry Teacher Signature of Principal
Date: Signature of
Roll No. External Examiner

3. ACKNOWLEDGEMENT
In the accomplishment of this project successfully, many people
have bestowed upon me their blessings and the heart pledged
support, this time I am utilizing to thank all the people who
have been concerned with project.
Primarily I would thank god for being able to complete this
project with success. Then I would like to thank my principal
Mrs. Lissiama Daniel and Chemistryteacher Mrs. Biji Kuriakose
whose valuable guidance has been the ones that helped me
patch this project and make it full proof success her suggestions
and her instructions has served as the major contributor
towards the completion of the project.
Then I would like to thank my parents and friends who have
helped me with their valuable suggestions and guidance has
been helpful in various phases of the completion of the project.
Last but not the least I would like to thank my classmates who
have helped me a lot.

4. CONTENTS
01.
AIM
02.
CERTIFICATE
03.
ACKNOWLEDGEMENT
04.
INTRODUCTION
06.
REQUIREMENTS 07.
PROCEDURE
08.
OBSERVATION
09.
CONCLUSION
10.
BIBLIOGRAPHY
05.
THEORY

5. INTRODUCTION
Caffeine is a central nervous system and metabolic
stimulant, and is used both recreationally and medically to
reduce physical fatigue and to restore alertness when drowsiness
occurs. It produces increased wakefulness, faster and clearer
flow of thought, increased focus, and better general body
coordination. The amount of caffeine needed to produce effects
varies from person to person, depending on body size and degree
of tolerance. Effects begin less than an hour after consumption,
and a moderate dose usually wears off in about five hours
Caffeine has a number of effects on sleep, but does not affect
all people in the same way. It improves performance during
sleep deprivation but may lead to subsequent insomnia. In shift
workers it leads to fewer mistakes caused by tiredness. In
athletics, moderate doses of caffeine can improve
sprint, endurance, and team sports performance, but the
improvements are usually not very large. Some evidence suggests
that coffee does not produce the ergogenic effects observed in
other caffeine sources. High doses of caffeine, however, can
impair athletic performance by interfering with coordination.

6. There is also evidence that caffeine may be helpful at high
altitude.
Caffeine constitutes about 3% of tea's dry weight. Tea also
contains small amounts of theobromine and theophylline, which
are stimulants and xanthines similar to caffeine.

7. THEORY
The most important methylated alkaloid that occurs
naturally is caffeine. Its molecular formula is CsH10N4O2. Its
IUPAC name is 1, 3, 7-trimethylxanthene and common name is
1-methylated thiobromine. Purely it is white, crystalline solid in
the form of needles. Its melting point is 1230
c. It is the main
active principle component of tea leaves. It is present in tea
leaves up to 3% and can be extracted by first boiling the tea
leaves with water which dissolves many glycoside compounds in
addition to caffeine. The clear solution is then treated with lead
acetate to precipitate the glycoside compounds in the form of
lead complex. The clear filtrate is then extracted with extracts
caffeine because it is more soluble in it then water.

8. Effects of caffeine:
Positive effects
Acetylcholine is associated with attention, concentration,
learning, and memory but there is no conclusive evidence
yet that caffeine has any effect on memory and cognitive
function.
Low doses of caffeine show increased alertness and
decreased fatigue.
Caffeine has been shown to increase the metabolic rate.
Negative effects
Caffeine can increase blood pressure in non-habitual
consumers.
High blood pressure is associated with an increase in strokes,
and cerebral vascular disease, which in turn increase the
risk of multi-infarct dementia.
Caffeine may reduce control of fine motor movements (e.g.
producing shaky hands)
Caffeine can contribute to increased insomnia and sleep
latency.

9. REQUIREMENTS
Tetley Green tea
Ripple tea
Sodium Carbonate
Petroleum Ether
beakers
glass rod
 filter paper
Separating funnel
Water

10. PROCEDURE
First of all, 50 grams of tea leaves were taken as sample and
150 ml of water was added to it in a beaker.
Then the beaker was heated up to extreme boiling.
The solution was filtered and 1gm Sodium Carbonate was
added to the filtrate, to convert tannins into water soluble
salts.
After that, the solution was transferred to a separating
funnel.
20 mL. of Petroleum ether was added to it.
Soon after, two layers appeared in the separating funnel.
We separated the lower layer.
This was repeated 2-3 times to extract maximum possible
caffeine present in the solution.

11. The solution then exposed to atmosphere in order to allow
ether to get evaporated.
The residue left behind was caffeine.
Then we weighed it and recorded the observations.
Similar procedure was performed with other sample of
tealeaves as well, and quantity of caffeine was observed in
them.

12. OBSERVATION
Ripple Tea
Weight of china dish - 43.60gms
Weight of china dish with precipitate -44.15gms.
Amount of caffeine - 0.55gms
 Tetley Green Label Tea (Lipton)
Weight of china dish - 43.60gms.
Weight of china dish with precipitate - 43.90gms.
Amount of caffeine - 0.30gms.

13. CONCLUSION
TEA SAMPLE AMOUNT OF CAFFEINE
Ripple Tea 0.55 mg.
Tetley Green Tea 0.30 mg.
Order of quantities of caffeine in different samples of tea leaves:
0
100
200
300
400
500
600
Ripple tea Tetley Green
Tea
Amountofcaffeine(mg.)
AMOUNT OF CAFFEINE IN EACH SAMPLE
Amount of caffeine
Ripple Tea > Tetley Green Tea

14. BIBLIOGRAPHY
Help from internet.
Help from teachers.

15. KENDRIYAVIDYALAYA NO.2
KATARI BAGH, KOCHI-04DEPARTMENTOF
CHEMISTRY
CERTIFICATE
This is to certify that MANJEET SINGH, a student of class XII-B has
successfully completed the research on the project carried out in the
chemistry lab under the guidance of Mrs. Biji Kuriakose (PGT Chemistry)
during the year 2016-17 in partial fulfillment of chemistry practical
examination conducted by AISSCE, New Delhi.
Signature of Chemistry Teacher Signature of Principal
Date: Signature of
Roll No. External Examiner

16. KENDRIYAVIDYALAYA NO.2
KATARI BAGH, KOCHI-04DEPARTMENTOF
CHEMISTRY
CERTIFICATE
This is to certify that BALAKRISHNA PRABHU B.N., a student of class
XII-B has successfully completed the research on the project carried out in
the chemistry lab under the guidance of Mrs. Biji Kuriakose (PGT
Chemistry) during the year 2016-17 in partial fulfillment of chemistry
practical examination conducted by AISSCE, New Delhi.
Signature of Chemistry Teacher Signature of Principal

17. Date: Signature of
Roll No. External Examiner