"Effects of nicotine and caffeine on blackworm" Essays and Research Papers

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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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    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
 ·    Pencil
 ·    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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    In this lab‚ caffeine was extracted from black tea‚ and green tea through a vacuum filtration‚ and a rotovap. The melting point of the sample of black tea was 219.12-236.05 ˚c‚ and for the green tea it was 176.22-227.6 ˚c. The % error of the melting point indicates how much error there was from the melting point taken experimentally. The % error of the melting point for black tea was 0.44%‚ and for green tea it is 3.15%.Since the theoretical melting point of caffeine is between 235-237 ˚c‚ we can

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    Extraction of Caffeine from Lipton® Tea Leaves Nathaniel Camangon*‚ Kaila Bumagat‚ Franz Mari Burgos‚ Remigio Callanta Department of Chemistry‚ College of Science‚ University of Santo Tomas‚ Manila‚ Philippines Abstract This experiment mainly focuses on the extraction of pure caffeine by multiple extraction from commercially acquired tea leaves and determining its purity by melting point determination. A 0.02% yield of pure caffeine was obtained from 10.4978g of tea leaves (4 tea bags).

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    of alkaloid caffeine from tea leaves Date Submitted: September 3‚ 2014 Abstract Caffeine is one of the main constituents of tea leaves. In this experiment‚ 0.0039 g of pure caffeine was isolated from tea leaves. This was done through solid-liquid extraction followed by multiple liquid-liquid extraction. Then crude material obtained was then purified by sublimation. The isolated caffeine was subjected to thin layer chromatography (TLC) together with a standard caffeine. The Rf value

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    This I Believe I believe in caffeine. I believe in caffeine because it keeps me alert‚ not quite awake‚ but alert. After a full night of studying‚ cramming on procrastinated homework‚ or just refusing to go to sleep‚ caffeine keeps you alert enough to be aware of the happenings of your day. But why would a 17 year old girl believe in caffeine‚ a chemical usually depended upon by truck drivers and stressed out adults working a daily 9-5? This is because of a 17 year old girl’s awareness of the

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    the extraction of caffeine from tea leaves to determine its % caffeine. The extraction process selectively dissolves one or more compounds in a mixture into an appropriate solvent. In this experiment‚ it was visible in the process wherein the components of the tea leaves were dissolved in two solvents‚ water and dichloromethane (DCM)‚ with DCM used for multiple extractions. The organic layer was evaporated and the determined % caffeine was 0.12%. Furthermore‚ the purified caffeine was subjected to

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