CONTENTS
i
1.
ACKNOWLEDGEMENTS
2.
INTRODUCTION
3.
HISTORY OF SOFT DRINKS
4.
THEORY
5.
AIM
6.
APPARATUS & CHEMICALS
7.
PROCEDURE A. pH B. Test for Carbon Dioxide C. Test for Glucose D. Test for Phosphate E. Test for Alcohol F. Test for Sucrose
8.
RESULT
9.
CONCLUSION
10. BIBIOGRAPHY
ACKNOWLEDGEMENTS
We would like to thank our Chemistry teachers, Mrs.Malini and Mrs. Sri Vidya, for their kind help
without which this project would not have been possible. We would also like to thank our lab assistant Ms.Ambika for her extraordinary help and ·
support.
HISTORY OF SOFT DRINKS The firs marketed soft drinks (non-carbonated) m the Western world appeared in the 17th century. They were made from water and lemon juice sweetened with honey. In 1767, the drinkable man-made glass of carbonated water was created by Englishmen Doctor Joseph Priestley. Carbonated water was for sale by the end of the 1700s; 1886 is key year for soft drink history; Coca-Cola, Dr Pepper, and Moxie were all introduced to the pharmacy-going public. Soft drinks have been under scrutiny for a variety of reasons. The foremost being the hazards posed by these drinks to health. Obesity, diabetes, gastric disorders are some of the major health problems caused by these drinks. Famous soft drink companies like Pepsi, Coca Cola etc have also been surrounded by controversy. In General, what started out as a healthy accompaniment to nutrition has morphed into a toxic addiction.
THEORY Soft drinks are generally composed of alcohol, carbgohydrates, carbon dioxide, phosphate ions etc. Soft drinks induce a sense of warmth and lightness. They taste tangy or sweet. Carbon dioxide is responsible for the formation of fizz on shaking the bottle. It is dissolved in water to form carbonic acid which is responsible for the tangy taste. Carbohydrates are naturally occurring organic compounds and are a major source of energy for our body. The general formula of carbohydrates is Cx (H20)y. On the basis of their behavior on hydrolysis, carbohydrates are classified ad: Monosaccharide, Disaccharides and Polysaccharides. Glucose is a monosaccharide with formula C6H1206. It occurs freely in nature: in ripe grapes, honey, sweet fruits etc. Sucrose is one of the most useful disaccharides in our daily life. It is readily available in nature; in juices, seeds and in many flowers. The main source of sucrose is sugar can juice which contains 15-20% of sucrose. The molecular formula of sucrose in C 12H22011 . It hydrolyses to give a mixture of glucose and fructose. Cold drinks are acidic in nature, due to presence of citric acid, phosphoric acid, caffeine etc. It's acidity can be measured by measuring the pH value.
AIM: To study and qualitatively analyze the contents of soft drinks available in the market. -
APPARATUS AND CHEMICALS REQUIRED: Apparatus •
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Test Tubes Test Tube Holder Test Tube Stand Stop Watch Beaker Bunsen Burner pHPaper Tripod Stand China Dish Wire Gauge WaterBath
Chemicals: Iodine Solution Potassium Iodide Sodium Hydroxide Lime Water Fehling's A&B Solution Concentrated Nitric Acid Benedict Solution Ammonium Molybdate •
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PROCEDURE:
A. pH Experiment: Small samples of cold drinks of different brands were taken in a test tube and put on the pH paper. The change in colour of pH paper was noticed and was compared with standard pH scale.
OBSERVATION: Sl.No Narne Of The Drink
,.
Colour Change
pH Value
1
Coca Cola
Pinkish
2-3
2
Sprite
Dark Orange
3
3
Fanta
Orange
3-4
Inference: Soft Drinks are generally acidic because of the presence of citric acid and phosphoric acid. pH values of cold drinks of different brand are different due to the variation in amount of acidic content.
B.
TEST FOR CARBON DIOXIDE
Experiment: As soon as the bottles were opened, one by one the sample was passed through lime water. The lime water turned kilky.
Observation SL.NO 1
NAME OF THE DRINK COCA COLA
CONCLUSION C02 IS PRESENT
2
SPRITE
C02 IS PRESENT
3
FANTA
C02 IS PRESENT
Inference All the soft drinks contain dissolved carbon dioxide in water. The carbon dioxide (CO2) dissolves in water to form carbonic acid, which is responsible for its tangy taste.
Chemical Reaction: Ca(OH)2(s) + C02 (g)
CaC03 (s) + H20(s)
C.
TEST FOR GLUCOSE
Experiment: Glucose is a reducing sugar acid. Its presence is detected by the following test:-
1. Benedict'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 dimks.
Observation: Sl.No Name
of the Observation
Conclusion
Drink 1
Coca Cola
Reddish Colour Precipitate
2
3
Sprite
Fanta
Reddish Colour
Glucose is Present Glucose is
Precipitate
Present
Reddish Colour
Glucose is
Precipitate
Present
Inference: All the samples gave positive test for glucose with Benedict's reagent. Hence all the drinks contain glucose.
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 water bath for I 0 minutes. Appearance of brown precipitate confirmed the presence of glucose in cold drinks.
Observation: Sl.No 1
2
3
Name of The Drink Coca Cola
Sprite
Fanta
Observation
Conclusion
Reddish Brown
Glucose is
Precipitate
Present
Reddish Brown
Glucose is
Precipitate
Present
Reddish Brown
Glucose is
Precipitate
Present
Inference: All samples gave positive test for glucose with Fehling's (A &B) solutions. Hence all the cold drinks contain glucose.
D. TESTFORPHOSPHATE Experiment: Small samples of each brand of cold drinks were taken in separate test tubes and Ammonium Molybdate followed by concentrated Nitric Acid (HNO3) was added to if The solution was heated. Appearance of canary
-
yeallow precipitate
confirmed the presence of phosphate ions in cold drinks.
Observation: Sl.No
Name of the
Observation
Conclusion
Drink 1
2
3
Coca Cola
Sprite
Fanta
Canary Yellow
Phosphate is
Precipitate
Present
Canary Yellow
Phosphate is
Precipitate
Present
Canary Yellow
Phosphate is
Precipitate
Present
Inference: All the soft drinks samples gave positive test for phosphate ions. Hence all the cold drinks contain phosphate.
E.
TEST FOR ALCOHOL
Experiment
Samples of each brand of cold drinks are taken in sample test tube and iodine followed by potassium iodide and sodium hydroxide (NaOH) solution is added to each test tube. Then the test tube are heated in hot water bath for 30 minutes yeallow colored precipitate confirmed the presence of alcohol in cold drinks. Observation: SL.NO NAME
OF THE OBSERVATION CONCLUSION
DRINK 1
COCA COLA
YELLOWPPT
ALCOHOL IS PRESENT
2
SPRITE
YELLOWPPT
ALCOHOL IS PRESENT
3
FANTA
YELLOWPPT
ALCOHOL IS PRESENT
Inference: All the Brands of Cold Drinks Contain Alcohol. Chemical Reaction: CH3CH20H+4I2+4NaOH
--7
CHI3 + HCOONa + 5Nai + 5H20
F.TEST FOR SUCROSE
Experiment: 5ml samples of each brand of cold drinks were taken in separate china dishes and were heated very strongly until changes occur. Black coloured residue left confirmed the presence of sucrose in cold drinks.
Observation: Sl.No 1
Name of the Drink
Coca Cola
Observation
Black Residue
Conclusion
Sucrose is Present
2
Sprite
Black Residue
Sucrose is Present
3
Fanta
Black Residue
Sucrose is Present
Inference: All the brands of cold drinks contain sucrose. But amount of sucrose varies in each brand of drink. Fanta contains highest amount of sucrose.
Result: After conduction several tests, it was concluded that the different brands of cold drinks namely: 1. Coca Cola 2. Sprite 3. Fanta
All contains glucose, alcohol, sucrose, phosphate and carbon dioxide. All cold drinks are acidic in nature. On comparing the pH value of different brands Coca Cola is the most acidic.
Among the four samples of cold drinks taken, Sprite has the maximum amount of dissolved carbon dioxide and Fanta has the minimum amount of dissolved carbon dioxide.
BIBLIOGRAPHY www.google.com www .icbse.net www .about.com NCERT textbook for class XII
