For both solid-liquid and liquid-liquid extraction techniques, solvents should be chosen by their miscibility in water (should be immiscible), they should have relatively low boiling points for faster and easier extraction, and they should be unreactive with the other substances being used in the experiment. The latter two components can be converted to their calcium salts which are insoluble in water. : an American History (Eric Foner), The Methodology of the Social Sciences (Max Weber), Principles of Environmental Science (William P. Cunningham; Mary Ann Cunningham), Brunner and Suddarth's Textbook of Medical-Surgical Nursing (Janice L. Hinkle; Kerry H. Cheever), Psychology (David G. Myers; C. Nathan DeWall). was added to the aqueous layer to help break up any emulsion is because a difference in trailer
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ball flask and placed in a steam bath so that the solvent would evaporate and leave a green The nucleophile attacks electrophile and reacts as an acid/base reaction, getting rid of the emulsions. was purified. COMPARING CAFFEINE CONTENT IN DIFFERENT SAMPLES OF TEA. of the separated solution. When dichloromethane was added, two layers formed: an organic and aqueous layer. To further perform the separation of caffeine Chloroform will - Filter Paper The basic property of caffeine comes from the lone pair of electrons found around the nitrogen. for ~15 minutes. A caffeine extraction experiment is a typical chemistry lab experiment. Introduction: Caffeine, nitrogencontaining basic compounds, is alkaloid and has a bitter taste that we extracted from tea plants and coffee. From the top of the funnel, methylene chloride was poured into the solution in increments of 5 mL. Individual spikes on the graph indicate the unique bond energies of certain functional groups. A cup of coffee or tea provides a 25- to 100-mg "Dose" of caffeine, which stimulates the central nervous system in a widely exploited manner. 9. Caffeine has a greater affinity for methylene chloride and will easily dissolve in this solvent over water; however caffeine is not the only organic substance found in tea that is capable of reacting with methylene chloride. 4. Tannins contained in coffee and are what give the coffee its dried. Today, caffeine is easily extracted and is used to make a variety of . The remaining solution was heated briefly until the volatile solvent evaporated, leaving behind solid caffeine. requirements? Placed 9-10g of tea leaves in a 400mL beaker. The extraction of the benzoic acid ,3-nitroaniline and 9-flourene mixtures by adding different amounts of solvents and extracting the acidic, basic and the organic . extraction of caffeine from tea lab report introduction. = .03 g / .25 g x 100 = 12 %. From the calculations made we can conclude that it is more efficient to extract caffeine from tea using two extractions instead of just one large amount. Caffeine is water soluble but so are some tannins and gallic acid which is formed in the process of boiling tea leaves. This spike represents the alkene portion of the caffeine molecule. compound. 11. The solution was transferred to a separate 100ml beaker to prevent mixing the bottom beaker. Using a separatory funnel extract three times with 15.0ml of dichloromethane gently rocking bath and forth the funnel venting the funnel often each time. A second crop of caffeine may form in the filtrate as the solvent evaporates. Correct writing styles (it is advised to use correct citations) The caffeine can then be extracted from the water by methylene chloride in almost pure form. Max. The funnel was inverted and opened so the gases would escape. Be sure to release the pressure 1. To remove the dichloromethane, the solution was transferred to a ball flask and placed in a steam bath so that the solvent would evaporate and leave a green residue. We added hexane to the left over residue and then dissolved the greenish-white caffeine residue in 5 mL of hot acetone the solution was a cloudy white. When isolated using Na 2 CO 3 solution, the tannins will become a salt. 0000061959 00000 n
Introduction Discussion Mass of Caffeine Mass of 100 cm3 round bottom flask, extracted caffeine, and magnetic stirrer - Mass of empty 100 cm3 round bottom flask and magnetic stirrer 49. Lab report for Experiment Purpose: What is the purpose of this lab? [1],[2],[3], Experiment 1: Isolation of Caffeine from Tea Leaves, Figure 3: Obtained IR Spectrum Graph of Caffeine. In commercial application, caffeine supplements pharmaceuticals and certain beverages such as coffee or tea. - Separatory Funnel The solution was cooled and a vacuum filtration was done to remove the caffeine crystals. Organic and Biological Chemistry. 0000001319 00000 n
Rinse again with 50 mL of water. of Americans consume some form of caffeine daily. Tea bags are used as the source of caffeine for this experiment. apparatus, The apparatus filtered slower than expected. The weight of the round-bottom flask empty was 54. Another source of lesser yield originated from techniques used to prevent the contamination of the methylene chloride solution. Extract the tea solution with 6 mL of dichloromethane (CH2Cl2, also called methylene chloride or DCM). Organic Chemistry. The objective of the experiment is to learn how to extract caffeine from tea, using basic organic chemistry techniques. Hot plate. The ground solid is then treated with a solvent that removed desired components selectively. and the organic layer was drained in the same 50mL Erlenmeyer used before. A liquid-liquid extraction was then performed to extract the caffeine from the mixture by adding dichloromethane. All rights reserved. The crystalline solid that precipitated was weighed 0000001144 00000 n
Total water used = 275 mL. dichloromethane (140mg/ml) than it is in water (22mg/ml). Using the proper extraction methods, the caffeine within a tea bag could potentially be isolated to yield a pure solid; the mass of this solid would reflect the actual yield of caffeine in the tea. cite it correctly. Erlenmeyer. Since we are not interested in Caffeine is the principle stimulant found in tea and coffee, and it can account for up to approximately 5% of the mass of the tea leaves. Use an organic solvent to extract the caffeine and related compounds from the water. 22 Round bottom Flask + Caffeine Calculate the mass percent caffeine in the tea leaves. Give at least three characteristics of chloroform that make it a good extracting solvent for caffeine. sodium sulfate Sodium sulfate serves as a drying agent in most reactions to absorb all excess water from the solution. Caffeine. Retrieved February 2, 2014, from http://employees.oneonta.edu/knauerbr/ch. Chromium and natural anhydrous caffeine are also included to help regulate blood sugar [6] levels and improve energy levels. Mass of round bottom flask with caffeine: 61 g, Total caffeine extracted: 61 g 61 g = 0 g, Mg of caffeine in 10 tea bags: 21 2 = 9 g x 55 mg = 521 mg, Percent recovery: 521 47 100 = 9 %, Copyright 2023 StudeerSnel B.V., Keizersgracht 424, 1016 GC Amsterdam, KVK: 56829787, BTW: NL852321363B01, The Methodology of the Social Sciences (Max Weber), Forecasting, Time Series, and Regression (Richard T. O'Connell; Anne B. Koehler), Campbell Biology (Jane B. Reece; Lisa A. Urry; Michael L. Cain; Steven A. Wasserman; Peter V. Minorsky), Biological Science (Freeman Scott; Quillin Kim; Allison Lizabeth), Chemistry: The Central Science (Theodore E. Brown; H. Eugene H LeMay; Bruce E. Bursten; Catherine Murphy; Patrick Woodward), Civilization and its Discontents (Sigmund Freud), Brunner and Suddarth's Textbook of Medical-Surgical Nursing (Janice L. Hinkle; Kerry H. Cheever), Business Law: Text and Cases (Kenneth W. Clarkson; Roger LeRoy Miller; Frank B. You may use it as a guide or sample for Ashwagandha root extract (125.00 mg), capsicum fruit extract (25.00 mg), and black pepper fruit extract (5.00 mg) may also help boost metabolism and suppress appetite. Added 4 of Calcium Chloride and Minutes, Collect the suspended solution in a After single extraction with 15mL, 0.178g of caffeine is in the water and 0.122g is in the dichloromethane. Save the purified caffeine in a sealed vial. The mass of caffeine from 2 Lipton tea bags was only 18.18% of the theoretical yield but in consideration of all the factors responsible for error, 18.18% is an acceptable value. To remove the dichloromethane, the solution was transferred to a 2. Caffeine Content in Tea/Coffee Sample (Extraction with water) TEA/COFFEE SAMPLES AMOUNT OF CAFFEINE (gm) Brook Bond Red Label 0.01 AVT 0.03 Eastern Eastea 0.02 Palat 0.04 3 Roses 0.02 Methylene chloride was added 2 more times to assure that all of the caffeine was reacted with. Sodium carbonate and hot water were added to the tea bags and was let to stand for about 7 minutes in order to bring the caffeine molecules out of the tea bags and into the aqueous solution. 4.6 = (17.8 100x) / (15x) X = 0.105g of caffeine in the water (0.178g 0.105g) = 0.073g in dichloromethane Total caffeine in dichloromethane is 0.195g. We waited until the solution was cool to the An emulsion will probably form. product Caffeine Weight = 0 The aqueous sodium carbonatesolution was cooled and we extracted it twice with separate 30-mL portions of dichloromethane into a separatory funnel. The purpose of this experiment was to perform a liquid-liquid extraction method to extract the caffeine from the tea bags that were provided, and then recrystallize the caffeine. solution, transfer to a The aim of this experiment is to extract caffeine from a sample of tea leaves by the Soxhlet extraction method. It has a density of 1 g/m. caffiene and the round Added 4.8g of Calcium Chloride and 125mL of water over the tea leaves. The CaCl2 stopped clumping together when excess water was removed. Student groups should develop their own procedure to test their selected variables. The yield was determined to be 1.2152 % of caffeine per one gram of instant tea. This new feature enables different reading modes for our document viewer. Although caffeine is capable of dissolving in water by forming hydrogen bonds, the greater affinity that caffeine has for methylene chloride breaks these bonds. into the 50 ml Erlenmeyer flask. that a pure sample of caffeine could be retrieved. To accomplish this the tannins Dont Next it was divided in 2 portions. Safety Lab coat, goggles, gloves. Although we had a crystalline caffeine substance before, we had to recrystallize it in order to remove the impurities (that caused it to have a green tinge to it rather than pure white). touch. Title Page no. There could have been an error with the balances, or the ball flask could not have been dried enough after washing. dichloromethane was added. must be performed in order to isolate the caffeine from coffee by use of organic and inorganic 2nd Official lab report 10% of lab grade. . Caffeine is found in many plants with coffee and tea being the most familiar. The solubility of caffeine is 22 mg/mL (25 C) and 670 mg/mL (100 C). 30-34) Edition: 1st Chapter: Chap. Caffeine is classified as an alkaloid meaning We began the experiment by measuring 5 grams of coffee grounds and 30ml of distilled The other important spike appears around 1600 Hz and 1750 Hz. INTRODUCTION Caffeine presents in tea and coffee. In this experiment, the organic solvent dichloromethane (CH2Cl2) is used to. To ensure that no water interferes with the interaction of caffeine and methylene chloride, sodium sulfate could be used to absorb any excess water that may have escaped from the tea solution1. separate beaker (Organic and Add 5-8 mL of hot acetone to dissolve the crude caffeine and transfer the solution to a 50 mL Erlenmeyer flask for recrystallization. funnel. Experimental. The dipole moment of the molecule outweighs the weak van der waals forces making it the strongest intermolecular force in caffeine. We believe that adding the hexane before the hot acetone to the residue during the recrystallization process caused the low amount of caffeine we successfully extracted in thisexperiment. After removing the tea leaves from ten tea bags the tea was weighed and placed in one large tea bag to be boiled for ten minutes in a large beaker filled with ~150 mL of water. A water/1-propanol/sodium chloride ternary system was found to be a suitable replacement for the more traditional water/organochlorine solvent systems. Caffeine is a base which can react with acids to form salts. The nucleophile attacks electrophile and reacts as an acid/base will be able to extract the tannin salt from the mixture. Includes: 1. If necessary, cool in an ice-water bath. Chemical Structures and Calculations, Percent Yield = Actual Yield / Theoretical Yield x 100 III. It was then distilled, and then the remaining dichloromethane was evaporated, leaving crude, greenish-white crystalline caffeine. 0000006403 00000 n
Experimental. Using a hot plate, it was boiled for 15 minutes. Caffeine is more soluble in organic substances so the dichloromethane was used with a separatory funnel to extract the caffeine from the aqueous sodium carbonate (the aqueous layer) and into the organic layer. In this experiment, we aimed to extract caffeine from the tea leaves in the tea bags provided beginning with a solid-liquid extraction method and then a liquid-liquid extraction. More caffeine was separated from water when doing two extractions (0.195g), using 30mL once separated less caffeine from water (0.174g). Take 500 ml beaker add 200 ml of distilled water to it. Following this, a separatory funnel was used to pour the mixture in. Caffeine is soluble in water at approximately 2.2 mg/ml at 25C, 180 mg/ml at 80 C, and 670 mg/ml at 100C. BioOrganic Lab. solubility difference in order to separate the desired compound. 2. 2. We couldnt calculate the yield of the procedure because of an error in the weighting. Work Cited temperature. Lab Report: Extraction of Caffeine from Tea Bags Measure out 10ml of tea solution and add it to a centrifuge tube. Due to the reaction, pressure built up inside the funnel, requiring the stopcock to be opened to release excess gas following each inversion. With a No. from our coffee grounds. Theory: Caffeine can be isolated from coffee beans through a series of solid-liquid extraction and liquid- 0000005958 00000 n
This is why the tea was boiled with water, because the caffeine is soluble in it. The purity of our extract should not have been affected because we vacuum filtered the cool solution that contained the crystals twice. 0000001542 00000 n
Tea bags. Caffeine is more soluble in methylene chloride than water because both caffeine and methylene chloride are organic substances while water is inorganic. Extracting Caffeine from Tea. Interpreting Infra-red Spectra. During the extraction the emulsions or solid insoluble 2021-22, Test Bank Varcarolis Essentials of Psychiatric Mental Health Nursing 3e 2017, Laporan Praktikum Kimia Dasar II Reaksi Redoks KEL5, Quick Books Online Certification Exam Answers Questions, 1.1 Functions and Continuity full solutions. but Tannins are acidic. Acknowledgement 3 2. Retrieved from IR Spectroscopy Tutorial:
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