"Effect of caffeine on daphnia" Essays and Research Papers

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    EXTRACTION OF CAFFEINE FROM TEA LEAVES ABSTRACT Caffeine extraction from the commercial tea leaves (Lipton Yellow Label Tea) that was done is multiple extraction. 4 tea bags were used in the experiment; tea leaves were weighed having 8.5333 grams. The leaves were boiled in a beaker with 150ml of water; the aqueous tea extract was transferred in a seperatory funnel mixed with DCM (20ml)‚ done thrice. The DCM layer was washed with 20ml 6M NaOH in the seperatory funnel; the organic layer

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    Extraction of caffeine from tea bags ABSTRACT Caffeine extraction from the commercial tea leaves (Lipton Yellow Label Tea) that was done is multiple extraction. 4 tea bags   were used in the experiment; tea leaves were weighed having 8.5333 grams. The leaves were boiled in a beaker with 150ml of water; the aqueous tea extract was transferred in a seperatory funnel mixed with DCM (20ml)‚ done thrice. The DCM layer was washed with 20ml 6M NaOH in the seperatory funnel; the organic layer was dried

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    Extraction of Caffeine from Tea Leaves Marc Tugaoen‚ Kristine Vanzuela‚ Rafael Villanueva‚ Justeen Wong Department of Chemistry‚ University of Santo Tomas‚ Manila‚ Philippines Abstract This experiment has been divided into 4 set-ups‚ first was the solid-liquid extraction‚ next was the liquid-liquid extraction‚ then the sublimation and last was the melting point determination. The solid-liquid and liquid-liquid extraction were both done during the first meeting‚ the DCM layer was filtered and

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    percent of the caffeine molecule dissociates in water‚ proving that the compound is a weak electrolyte. A substance that completely dissociates in a solution‚ such as water‚ is considered an electrolyte and can therefore conduct electricity. This dissociation is caused by the atoms’ minimal nuclear charge‚ allowing the substance to break apart entirely into its ions. Ions are mobile‚ which induces a current and contributes to the substance’s high electrical conductivity. Caffeine is composed of atoms

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    Abstract: Caffeine‚ (C8 H10 N4 O2) a white‚ crystalline alkaloid known as a nervous system stimulant found commonly in tea leaves and coffee‚ can be extracted using the method of sublimation with the use of Methylene Chloride (CH2Cl2) and Sodium Hydroxide; both can repeatedly rinse the green (unroasted) coffee beans from the caffeine. Keywords: Caffeine‚ Methylene Chloride‚ Sodium Hydroxide‚ Anhydrous Sodium Sulfate I. Introduction Caffeine is an alkaloid of the methylxanthine family. Its chemical

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    Caffeine Concerns How many times have you felt a bit tired and decided to rely on an energy drink‚ a cup of coffee‚ or a can of cola to charge your body with caffeine and boost your energy levels to maximum? If your answer is “frequently” then you are on a precarious path to poor health. Not only does caffeine have numerous emotional side effects‚ it will also disrupt your sleep‚ and cause harm to your body. For all of its immediate benefits‚ caffeine is one of the most harmful substances in the

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    The effect of caffiene

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    The effects of caffeine on the heart rates of Daphnia. Introduction In the water flea‚ Daphnia‚ the single‚ small heart is easily visible when viewed under a low power microscope. The heart rate can be monitored and measured in different conditions‚ such as change in water temperature‚ or in this case‚ the concentration of chemicals added to the water they habitat. A change in daphnia heart rate under the influence of a concentration of caffeine solution creates a procedure providing an interesting

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    Extraction of Caffeine from Thea sinensis Abstract Extraction of Caffeine from Thea sinensis main objective is to isolate‚ purify characterized caffeine from tea leaves. Sublimation technique was used to get the % yield which is 0.07%. The melting point of the standard caffeine with the sublimate is 229°C. Introduction The active ingredient that makes tea and coffee valuable to humans is caffeine. Caffeine is an alkaloid; a class of naturally occurring compounds containing nitrogen and

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    Caffeine Ruler Reaction Time Test * OBSERVATION/ASK QUESTION * INTRODUCTION/RESEARCH * HYPOTHESIS * EXPERIMENT/DATA * CONCLUSION Materials
 ·    Ruler ·    Paper
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 ·    Chart ::OBSERVATION:: Those drinking coffee appear to be more alert in class. Does drinking coffee improve mental and physical function? } } { { Can the effects of coffee alter coordination? ::HYPOTHESIS:: Caffeine improves your mental &

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    Isolation of caffeine from tea leave Abstract:- Introduction:- Caffeine is probably the most commonly used addictive drug. This drug is found in a number of things ingested by people. It belongs to a group of nitrogen bases called purines. Because caffeine possesses these base-like properties‚ it is described as an alkaloid. They usually taste bitter and often are physiologically active in humans. The structure of caffeine is shown below. Figure 1: Structure of Caffeine In this experiment

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