Extraction of Caffeine from Tea Leaves
The purpose of this experiment is to extract caffeine from tea leaves using different solubility characteristics of caffeine in different solvents. The technique used in this experiment is liquid-liquid extraction. Caffeine are known stimulants that has physiological effects on humans such increasing alertness and reducing tiredness and sleep. This organic substance is also a diuretic and causes vasodilation of blood vessels. There are side effects of caffeine with high dosage such as insomnia and headaches and prolong usage may lead to dependence on caffeine. Caffeine can be found in tea leaves, coffee, kola nuts and cocoa beans with varying amounts. About 5% of the leaf weight comprises …show more content…
Caffeine, tannins (phenolic substances) and a little chlorophyll can also be found in tea leaves. Hot water extraction can be used to separate caffeine from the tea leaves (mainly cellulose) as water can form hydrogen bonds with water and solubilise (water has higher solubility at higher temperatures). However, tannins are also water soluble but they display acidic properties instead. Thus, a basic salt like sodium carbonate can be added to bind to tannins to form a salt. Although now both the tannins salt and caffeine are water soluble, using an organic solvent, dichloromethane, renders tannins salt insoluble. Caffeine is more soluble in dichloromethane (14g/100g) than in water (2g/100g). Caffeine will dissolve in the dichloromethane phase while tannins salts remain in the aqueous phase. Addition of sodium sulphate will act as a drying agent and evaporation of the dichloromethane solution would yield pure caffeine which is white in …show more content…
However, the percentage yield and melting points did not meet the expected results. 0.812% caffeine yield of crude caffeine was obtained, which is much lower than the expected percentage yield of 5%. The melting point of the caffeine obtained, 221 ºC, was also lower than the expected melting point of crude caffeine which is 238 ºC. This shows that the caffeine obtained is not pure and there were possible mistakes that occurred during the experiments that caused caffeine loss.
One of the possible reasons for the poor result could be that the techniques were basic. We used a hot water extraction, and organic solvent extraction and a rotary evaporator technique which could not have given us crude caffeine. Further purification steps needs to be conducted in order to obtain crude
Click here to unlock this and over one million essaysShow More
Therefore, liquid-liquid and acid-base extraction techniques were successfully performed to separate the components of the Excedrin tablet. According to the TLC analysis results, the compounds (aspirin, acetaminophen, and caffeine) were successfully isolated from the analgesic (Excedrin tablet). In figure 1, the separation of the compound in the TLC analysis correlates with the TLC analysis in figure 2. Furthermore, Rf index calculations of the TLC analysis demonstrated that the compounds (aspirin, acetaminophen, and caffeine) were separated. The Rf calculations of aspirin in table 1 shows an Rf value of .491; however, in table 2 the Rf value of aspirin was calculated to be .784.
According to Yong, Coffee Berry Borers are beetles that can make holes into coffee berries and lay eggs in the bean itself. The experiment was to see why the Coffee Berry Borer can withstand caffeine while other beetles clearly can’t stand its own with the poisonous caffeine. Ceja-Navarro and his team set up an experiment where they tested the beetles by first examining the feces of their normal diet. Then they promptly fed the beetles with an antibiotic and once again examined the feces. The feces of the beetles that were fed antibiotics was chock full of caffeine.
In “Java Man,” Malcolm Gladwell insists upon the importance and reliance that humans have on caffeine, and he states that “there is no drug quite as effortlessly adaptable as caffeine” (248). He highlights the significance of caffeine by revealing the history and using claims from popular advertisements such as Coca-Cola, historical figures like Paul Erdös, and scientific facts of how caffeine effectively works in humans’ bodies. Not only does Gladwell shares historical context, he also conveys a humorous tone and uses compelling evidence. By showing the significance of caffeine, Gladwell dates back to the eighteenth century to show how caffeine has affected people throughout history. First, the author uses a Coca-Cola advertisement from the
First, two grams on an unknown white compound were given. The possible compounds the known could be were CaCO3, KNO3, NH4Cl, CaCl2, K2SO4, (NH4)2SO2, Ca(NO3)2, NaC2H2O2, K2CO3, MgCl2, Na2CO3, 0.1 M AgNO3, MgSO4, NaCl, 0.2 M BaCl2, KCl, NaSO4, Mg(s), HCl, HNO3, NaOH, HC2H3O2, H2SO4, and KOH. The solubility test required using a scale to measure .575 of our unknown white compound. The unknown compound was measured in a 100 mL beaker.
In this lab, three unknown compounds were separated from a mixture and identified by melting point. Unknown mixture #124 has components of acid, base and neutral compound. The compounds were identified by melting point and matched up with the known melting points from a given list. In order to identify the compound it was important to separate by dissolving the mixture in an organic solvent which was not soluble in water, and then extracting the solution first with HCl, and then dilute sodium hydroxide solution. From the separation mixture, the aqueous layer were obtained and labeled as TT-1 (base), TT-2(acid) and TT-3 (neutral) in three different test tubes for later recovery.
The chloroform and caffeine mixture was collected and into a conical flask labeled A. The remainder of the solution was discarded. This was repeated for beakers B and C. 9. Sodium sulphate was then added to each beaker to dry the liquid by getting rid of any remaining water from the solution. The sodium sulphate was then filtered and discarded.
Malcolm Gladwell’s Java Man a description of caffeinated beverages depicts in western culture. He provides information to reinforce his argument of caffeine embodies in the work-ethic of society. Gladwell discusses examples of caffeinated beverages through examples of historical, social, and the modern’s purpose to illustrate the cultural importance of caffeine in the west. Gladwell’s writing style establishes factual background information in the social class. In the eighteenth century, caffeinated beverage known as coffee symbolized the rise of the middle class; meanwhile, cocoa, or chocolate, represented the luxury of the aristocracy.
Intro: Separation and purification of an unknown/complex compound can be done by using techniques such as liquid-liquid extraction, solid-liquid extraction, recrystallization, melting point, and thin layer chromatography. In this experiment, these techniques were used to separate excedrin’s components containing caffeine, excedrin, and acetaminophen, Each component has its own chemical properties and characteristics such as polarity, reactivity, and solubility. Knowing how to separate and purify compounds from each other is an important skill within in a lab setting. A few techniques for first initially separating compounds apart are liquid-liquid extraction and solid liquid extraction. Liquid-Liquid extraction involves using a seperatory funnel and release on varying solubities and different solids in immiscible solvents.
Although the value of the isolated caffeine is nearly double that of the pure caffeine, it appears that caffeine was separated from Excedrin, but the sample was not pure. It still had other analgesics present. This is concluded from the location
Unfortunately, it is possible to have an overdose of caffeine or a caffeine withdrawal. If too much caffeine is ingested, it can cause hallucinations and confusion. If someone is used to having caffeine on a regular basis, and then doesn’t have it for a while, it can cause irritability, drowsiness, nausea, and anxiety. Caffeine can also cause raised levels of stomach acid, which can cause heartburn. It is not a good thirst quencher because it signals your body to get rid of water.
How strong the effects of the stimulant are is an area of debate, but some studies show that any amount above 400 milligrams of caffeine per day is unsafe for adults, and particularly dangerous for children (Mayo Clinic). Drinking amounts above this causes a variety of neurological side effects, such as irritability, insomnia, nausea, and anxiety (Drugs.com). Studies have also found that L-Theanine, a major chemical found in caffeinated tea, makes these effects stronger and more pronounced, as it allows your body to absorb the caffeine more efficiently (J, Bryan). But you do not need to consume a large amount of caffeine to experience these side effects, even in the average person just a small dosage can cause pronounced symptoms, though they are less severe in strength (Mayo Clinic). Certain people and groups are vastly more susceptible to caffeine than others as well (Persad, Leeana Aarthi Bagwath).
Whenever a consumer uses an energy drink a series of effects begin in his/her body. The organism receives an instant boost as the caffeine successfully manages to block the duties of the adenosine, a chemical located in the brain whose function is involved with sleeping. After the completion of the process caffeine forces part of the neurons in the brain to lighten up, which later on causes the body to release the hormone adrenaline. When the hormone is active it forces the liver to provide the bloodstream with additional
Coffee is one of the most popular drinks in the world. In fact, it is estimated that every year, more than 400 billion cups of coffee are consumed all across the world. For many, it is the choice of drink early in the morning before work while for others it is the drink of choice when they want to burn the midnight oil. Well, whatever the case, there are many benefits in drinking coffee and some are quite shocking and unexpected too! 1.