CHEMISTRY PROJECT

INTRODUCTION A soft drink, also referred to as soda, soda pop, or fizzy drinks, is a non-alcoholic beverage usually containing water and a flavouring agent. Many of these beverages are carbonated and sweetened with either sugar, or high-fructose corn syrup, and they may contain additional ingredients such as fruit juice. They are called “soft” in contrast to “hard” because “hard” generally refers to drinks with a significant alcohol content. Small amount of alcohol may be  present in a soft drink, but it it must be less than 0.5 % of the total total volume if the drink is to be considered non-alcoholic.

Types of soft drinks: Widely, soft drink includes cola cola , lemon lime , root beer , orange soda , grape soda , cream soda , ginger ale , flavoured water, sparkling lemonade , sparkling water , iced tea, sweet tea , squash and fruit punch. Soft drinks do not contain milk or any other dairy products. Beverages that are not soft drinks include hot chocolate, hot tea, coffee, milk shake, juice and iced tea Some people drink soda pop as if it is water, some even instead of water. Sure , the primary ingredient is water , but , with all the other “ stuff ” it contains it can have a toxic , poisonous ,lethal , venomous , seriously harmful effect on your entire body. Drinking soda pop is sure way to age faster. Soda pop has an alarming amount of sugar, calories and harmful additives in it that have absolutely no nutritional value. Studies have linked soda to osteoporosis, obesity, tooth decay and heart disease. And we wonder why we can‟t lose weight and why we have health problems. We encourage illness and disease little  by- little every day by not preventing preventing their cause.

APPARATUS REQUIRED: Test Tubes

Test Tube Holder Test Tube Stand Stop Watch Beaker Burner  pH Paper Tripod Stand China Dish Wire Gauge Water Bath

CHEMICALS REQUIRED: Lime Water Benedict „s Solution Fehling‟s Solution A & Fehling‟s Solution B Concentrated Nitric Acid (HNO 3) Ammonium Molybdate Iodine Solution Potassium Iodide Solution Sodium Hydroxide

Finding pH EXPERIMENT: Few drops of the soft drink sample of each brand was taken in separate test tubes and put on the pH paper. The change in the colour of pH paper was noted for each sample and was compared with the standard pH scale.

OBSERVATION: SR. NO.

NAME OF THE SOFT

COLOUR CHANGE

 pH value

1. 2. 3. 4.

DRINK FANTA LIMCA COCA COLA SPRITE

INFERENCE: The acidic nature of soft drinks is because of the presence of citric acid and  phosphoric acid in them . pH values of soft drinks of different brands are different due to the variation in amount of acidic contents in them.

TEST FOR CARBON DIOXIDE EXPERIMENT: As soon as the bottles of soft drinks were opened, the gas evolved from the samples was  passed through lime water. Simultaneously Simultaneously the time interval for which which the soft drink  produced the brisk effervescence was noted.

OBSERVATON: SR. NO.

1. 2. 3. 4.

NAME OF THE SOFT DRINK FANTA LIMCA COCA COLA SPRITE

TIME TAKEN(SEC)

CONCLUSION

CO2 is present CO2 is present CO2 is present CO2 is present

INFERENCE: The lime water turned milky. All the soft drink samples contained dissolved carbon dioxide in water. The carbondioxide (CO2) dissolves in water to form carbonic acid, which is responsible for soft drink‟s tangy taste.

TEST FOR GLUCOSE Glucose is a reducing sugar due to the presence of an aldehyde in its structure. Its presence is detected using the following tests:

1. BENEDICTS’S REAGENT TEST: EXPERIMENT: Soft drink samples of different brands were taken in test tubes and a few drops of Benedict‟s reagent was added to each test tube. The test tubes were heated for a few seconds. Formation of reddish colour precipitate confirms the presence of glucose in soft drinks.

OBSERVATON: Sr. No. 1.

Name of the soft drink Fanta

2.

Limca

3.

Coca cola

4.

Sprite

Change seen

Conclusion

Reddish  precipitate Reddish  precipitate Reddish  precipitate Reddish  precipitate

Presence of glucose Presence of glucose Presence of glucose Presence of glucose

INFERENCE: All the samples gave positive test for glucose g lucose with Benedict‟s reagent. Hence all the soft drinks contain glucose. The principle of Benedict's test is that when reducing sugars are heated in the presence of an alkali, they get converted to powerful reducing compounds 2+ known as enediols. Enediols reduce the cupric ions (Cu ) present in the Benedict's reagent + to cuprous ions (Cu ) which get precipitated get precipitated as insoluble red copper(I) red copper(I) oxide.

2. FEHLING’S SOLUTION TEST

EXPERIMENT: Small samples of soft drinks of different brands were taken in test tubes and a few drops of Fehling‟s A and Fehling‟s B solution were added add ed in equal amounts. The test tubes were heated in a water bath for 10 minutes . Appearance reddish precipitate confirms the presence of glucose in soft drinks.

OBSERVATON: Sr. No. 1.

Name of the soft drink Fanta

2.

Limca

3.

Coca Cola

4.

Sprite

Change seen

conclusion

Reddish  precipitate Reddish  precipitate Reddish  precipitate Reddish  precipitate

Presence of glucose Presence of glucose Presence of glucose Presence of glucose

INFERENCE: All the samples gave positive test for glucose with Fehling‟s (A & B) solutions. Hence all the soft drinks contain glucose. The bistartratocuprate(II) complex oxidizes the aldehyde to a carboxylate anion, and in the process the copper(II) ions of the complex are reduced to copper(I) ions. Red copper(I) oxide then precipitates out of the reaction mixture, which indicates a positive result .

TEST FOR PHOSPHATE EXPERIMENT: Small samples of each brand of soft drinks were taken in separate test tubes and concentrated Nitric Acid (HNO 3) was added, then Ammonium Molybdate solution was added. The solution was heated. Appearance of canary-yellow  precipitate confirms the presence of phosphate ions in soft drinks.

OBSERVATON: Sr. No. 1.

Name of the soft drink Fanta

2.

Limca

3.

Coca Cola

4.

Sprite

Change seen

conclusion

Canary yellow  precipitate Canary yellow  precipitate Canary yellow  precipitate Canary yellow  precipitate

PO43- is present PO43- is present PO43- is present PO43- is present

INFERENCE: All the soft drinks samples gave positive test for phosphate ions. Hence all the cold drinks contain phosphate

TEST FOR ALCOHOL EXPERIMENT: Small samples of each brand of soft drinks were taken in separate test tubes and Iodine followed by Potassium Iodide and Sodium Hydroxide (NaOH) solution was added to each test tube. Then the test tubes were heated in hot water bath for 30 minutes. Appearance of yellow coloured precipitate confirms the presence of alcohol in cold drinks.

OBSERVATON: Sr. No. 1. 2. 3. 4.

Name of the soft drink Fanta Limca Coca Cola sprite

Change seen

Conclusion

INFERENCE: All the soft drink samples gave negative test for alcohol. Hence none of the soft drinks contain alcohol.

TEST FOR SUCROSE EXPERIMENT: 5 ml samples of each brand of soft drinks were taken in separate china dishes and were heated very strongly . Formation of a black black coloured residue confirms the presence of sucrose.

OBSERVATON: Sr. No.

Change seen

Conclusion

1.

Name of the soft drink Fanta

Black residue

2.

Limca

Black residue

3.

Coca Cola

Black residue

Sucrose is  present Sucrose is  present Sucrose is

4.

Sprite

Black residue

 present Sucrose is  present

INFERENCE: All the brands of soft drinks contain sucrose. But the amount of sucrose varies in each brand of soft drink. Fanta contains the highest amount of sucrose.

RESULT: After conducting several tests, it was concluded that the different brands of soft drinks namely: 1. Fanta 2. Limca 3. Coca Cola 4. Sprite All contains glucose, 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 acidic and Limca is least acidic acidic of all the four  brands taken. 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.