"Effect of caffeine on daphnia" Essays and Research Papers

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    Extraction of Caffeine from Tea Leaves Introduction Caffeine is soluble in boiling water and as a result it is easily extracted from tea bags by steeping in hot water. This process leaves behind the water insoluble portions of the tea bag. However‚ water extracts more than just caffeine‚ so a final separation is done with an organic solvent that will dissolve primarily caffeine. The organic solvent used in this experiment is Dichloromethane (CH₂Cl₂). Dichloromethane is less polar than water

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    essay aims to find out coffee’s beneficial effects on human body.coffee is one of the most popular beverages in the world‚ more and more populations all over the world love to begin their day with a cup of coffee.Almost a third of the world’s people drinks coffee. But coffee was not recognized a healthy drink. It has a history of being blamed for many disease.Coffee can stimulants parts of the human body‚ such as heart and muscles because of its caffeine content.Caffeine is a natural stimulant existent

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    The Health Effects of Caffeine on the Human Body Caffeine‚ known as a “drug” is something that many people consume on a daily basis. It is very common and can be consumed in many different ways. Caffeine can be consumed through drinks‚ medicine and/or foods. In one way or another‚ caffeine is used as a stimulant to help during the day when most being to feel tired or sluggish. Caffeine is considered a pick me up and helps to boost ones energy level in order to complete daily tasks. The taste of caffeine

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    Weight (g) Tea Leaves 5.5783 Crude Caffeine 0.0246 Empty Beaker 117.5350 Beaker + Crude Caffeine 117.5596 The table above shows the weight of the sample tea leaves‚ the crude caffeine content in the sample‚ the empty beaker used in the extraction‚ and the beaker with the crude caffeine. It is induced from there that for that amount of sample tea leaves‚ which is equivalent to three bags of Nature’s Pride Tea; there is a 0.0246 g content of crude caffeine for every 3 servings of this tea.

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    proposition. Related Literature and Studies Downsides in Caffeine New research from John Hopkins Medical School shows that performance increases due to caffeine intake are the result of caffeine drinkers experiencing a short-term reversal of caffeine withdrawal. In essence‚ coming off caffeine reduces your cognitive performance and has a negative impact on your mood. Drinking caffeine triggers the release of adrenaline. When caffeine puts your brains and body into this hyper-aroused state‚ your

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    TITLE: Effect of the caffeine on the heart rate OBJECTIVE: To investigate the effect of the caffeine on the heart rate of living organisms. INTRODUCTION: * Daphnia Daphnia are small‚ planktonic crustaceans‚ between 0.2 and 5 mm in length. Daphnia are members of the order Cladocera‚ and are one of the several small aquatic crustaceans commonly called water fleas because of their saltatory swimming style (although fleas are insects and thus only very distantly related). They

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    MULTIPLE EXTRACTION OF CAFFEINE FROM DRIED TEA LEAVES USING DICHLOROMETHANE Delos Reyes‚ K.‚ Dizon‚ G.J.‚ Enriquez‚ J.R.‚ Estrada‚ G. and Garcia C. Group 4 2G Med Tech Organic Chemistry Laboratory ABSTRACT Caffeine was extracted from dried tea leaves by multiple extraction technique. 10g of tea leaves was boiled in a solution of 4.4 g anhydrous sodium carbonate and 100ml distilled water and was extracted three times using 20 ml of dichloromethane. Theresidue was collected by decanting

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    extraction method to extract the caffeine from the tea bags that were provided‚ and then recrystallize the caffeine. The solvents used in the experiment were an aqueous sodium carbonate and dichloromethane (DCM). Anhydrous calcium chloride pellets were used to dry the solution and emulsion layer and the DCM was then decanted. After washing the anhydrous calcium chloride pellets with more DCM‚ the solvent was evaporated‚ leaving greenish-white crystalline caffeine residue weighing about .25 mg.

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    Describe an alternative method for evaporation of the CH2Cl2 Can be steamed and then rinsed with ethyl acetate for several hours‚ and then rinsed with water‚ or can be soaked in a bath of CO2 and run through water‚ making carboxylic acid. (2) Caffeine: (4) Repeated exposure can produce general deterioration of health by an accumulation in one or many human organs. First Aid Measures: Eye contact - Immediately flush eyes with plenty of water for at least 15 minutes. Cold water may be used. WARM

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    The article‚ Biotreatment of wastewater using aquatic invertebrates‚ Daphnia magna and Paramecium caudatum‚ mainly pertains to the idea of cleaning dirty‚ polluted water. Every since we‚ as a society‚ have switched from an agrarian to an industrial way of life‚ our waters have become increasingly polluted. Thus‚ scientists have researched conducted experiments in order to attain clean water. One of the failed attempts of attaining clean water was one in which they tried to use chemicals. Unfortunately

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