Abstract This work describes 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
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There has been much debate in recent years among politicians‚ military officials‚ and civilians on whether or not the U.S. should be fully withdrawn from Afghanistan‚ regardless of the country’s economic and military capabilities. There has also been a proposed timetable‚ which President Obama says is in effect and currently being executed‚ to have up to ninety percent of our military personnel out of the country by no later than 2014. It is imperative that we extract our forces out of Afghanistan
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Extraction of DNA from Cheek Cells Gene Smith February 29th 2013 INTRODUCTION DNA‚ deoxyribonucleic acid‚ is the genetic material of every living organism and is found in the nucleus of eukaryotic cells. DNA is often called the ‘blueprint for life’ because it contains the necessary information to carry out all the living processes of the cell (1).The purpose of this lab was to extract DNA from human cheek cells. The isolated DNA could be used inmapping or sequencing‚ PCR‚ crime scene investigation
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Isolation‚ purification and characterization 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
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Name: Cindy Nguyen Date: 7/11/12 Classifying Acids and Bases Purpose: To observe the typical properties of acids and bases. Hypothesis: The typical properties of acids are identical to the typical properties of bases. Materials: * * Goggles * Well plate * 2 strips of magnesium ribbon * Sodium hydrogen carbonate (baking soda)‚ NAHCO3 * Red litmus paper * Blue litmus paper * Conductivity tester * Beakers of: * Tap water * Dilute
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Extraction of Caffeine from Lipton Yellow Label Teal Leaves Arlie Bamiano‚ Jealine Bernabe‚ Petrenne Caimbon*‚ Jhia Caso Department of Biology‚ University of Santo Tomas Abstract In order to extract pure caffeine from Lipton Yellow Label tea leaves‚ several extractions and phase transition techniques were employed to 6.5029 grams of sample. Initially‚ the tea leaves were boiled in water to extract tea from the leaves (Solid-Liquid Extraction). After extracting the tea‚ several steps of
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concept of a conjugate acid-base pair. Using equilibrium law and K‚ explain the relationship between the strength of an acid/base and its conjugate. Conjugate Acid-Base Pair: Conjugate acids and bases were presented by Bronsted-Lowry‚ who was a chemist who proposed the theory that both acids and bases required the transfer of a proton in order for there to be a reaction. An acid will donate a proton (proton donor)‚ forming what is considered to be a conjugate base. When the base accepts a proton (proton
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also ductile‚ making it a very useful metal. Aluminium readily makes alloys with copper‚ zinc‚ magnesium‚ manganese and silicon. Aluminium foil is 92-99% pure aluminium. Other uses of aluminium alloys include computers (all Apple MacBooks are made from aluminium)‚ cooking utensils‚ transportation (aircraft‚ rockets and cars mainly because of their high strength-to-weight ratio)‚ packaging‚ water treatment‚ street lighting etc. Aluminium is the most abundant metallic element in the lithosphere‚ thought
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Acid-Base Titrations 6-3: Concepts in Acid-Base Titrations Titrations provide a method of quantitatively measuring the concentration of an unknown solution. In an acid-base titration‚ this is done by delivering a titrant of known concentration into an analyte of known volume. (The concentration of an unknown titrant can also be determined by titration with an analyte of known concentration and volume.) Titration curves (graphs of volume vs. pH) have characteristic shapes. The graph can be used
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Exercise 10: Acid/Base Balance Worksheet Assignment Due: Week 1 Student instructions: Follow the step-by-step instructions for this exercise found in your text and record your answers in the spaces below. Submit this completed document by the assignment due date found in the Syllabus. Please make sure that your answers are typed in RED. Please type your Name and Student ID Number here: Michael Rowland 4035527 Respiratory Acidosis and Alkalosis Activity 1: Normal Breathing
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