"Purification of caffeine by sublimation" Essays and Research Papers

Sort By:
Satisfactory Essays
Good Essays
Better Essays
Powerful Essays
Best Essays
Page 12 of 50 - About 500 Essays
  • Powerful Essays

    Daphnia Caffeine Experiment

    • 3335 Words
    • 14 Pages

    EFFECT OF CAFFEINE ON HEART RATE LECTURER : MDM ZAKIAH BINTI ZAKARIA TITLE The effect of caffeine on heart rate OBJECTIVE To determine the effect of caffeine on heart rate of daphnia INTRODUCTION Caffeine‚ medically known as trimethylzanthine. Its chemical formula is C8H10N4O2. When in pure form‚ caffeine is a white crystalline powder that taste very bitter. 1The most common way of acquiring pure caffeine is the process of decaffeinating coffee and tea. Caffeine is found

    Premium Caffeine Tea Coffee

    • 3335 Words
    • 14 Pages
    Powerful Essays
  • Satisfactory Essays

    Caffeine in Tea Samples

    • 2358 Words
    • 10 Pages

    T4/13/13 Chemistr y Pr oject to Deter mine the Caffeine in Tea Samples Chemistry‚ C++‚ Physics‚ Maths‚ Biology‚ Social Science Home Biology C++ Chemistry IP Maths Physics Social Science Ty pe tex t to s earc h here... Home > Chemistry > Chemistry Project to Determine the Caffeine in Tea Samples Chemistry Project to Determine the Caf f eine in Tea Samples Determination of Caffeine in Tea Samples ACKNOWLEDGEMENTS First of all T would like to thank my cousin brother M r. Ne e raj Naithani Research

    Premium Coffee Caffeine Tea

    • 2358 Words
    • 10 Pages
    Satisfactory Essays
  • Powerful Essays

    Caffeine and Reaction Time

    • 1286 Words
    • 6 Pages

    Daniel Kim 12-3-12 HBS‚ period 1 Reaction time experiment Caffeine and Reaction Time 1) Identify the Problem or Question How does the consumption of caffeine affect the reaction time of the nervous system? 2) Introduction Purpose of the experiment: To identify the whether or not caffeine increases or decreases the reaction time of the nervous system. In our experiment‚ we have decided to use all the “cases” which will test how fast a signal from our brain will be sent to our

    Premium United States Psychology Management

    • 1286 Words
    • 6 Pages
    Powerful Essays
  • Good Essays

    HPLC Analysis of Caffeine

    • 980 Words
    • 4 Pages

    Date: 9-10-13 Title: HPLC analysis of Caffeine Lab Partners: Objectives: 1) The main objective of this lab is to gain experience in using and reading results from the HPLC machine. 2) The first step is to inject a series of caffeine standards into the machine in order to get results/values of peak height and area. 3) The next step is to investigate the effects of a series of HPLC parameters on Retention time‚ peak height and peak area. 4) To use above data from peak height and area

    Premium Chromatography High performance liquid chromatography

    • 980 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Caffeine Persuasive Essay

    • 1569 Words
    • 7 Pages

    Do you know why children should not drink coffee? These days lifestyle of children has been changing regarding the way that children drink. Caffeine is one of the biggest problems in the world. Most companies make many things from caffeine such as coffee‚ tea‚ chocolate‚ soda‚ and Energy Drinks. However‚ children under 18 years old don’t know if these things can be dangerous for their health. Children eat or drink these things because parents didn’t tell them that are not good for their health.

    Premium Coffee Caffeine

    • 1569 Words
    • 7 Pages
    Good Essays
  • Good Essays

    Caffeine C and E

    • 369 Words
    • 2 Pages

    most common risk factor of liver cancer‚ so American adults may have something to celebrate as they sip their morning cup. A study of one hundred twenty-four older adults‚ ages sixty-five to eighty-eight‚ with mild cognitive impairment found that caffeine and coffee intake was associated with a reduced risk of developing Dementia and early onset Alzheimer’s. Coffee is known to be problematic for acid reflux and heartburn. Acid reflux and heartburn can be caused by coffee due to the way it relaxes

    Premium Coffee Caffeine Gastroesophageal reflux disease

    • 369 Words
    • 2 Pages
    Good Essays
  • Good Essays

    -------------------------------------------------   Isolation of Caffeine from Coffee Date of laboratory work: 10/9/2012 5:00-7:45 Date of report written: 10/15/2012 Introduction: The purpose is to isolate caffeine from coffee by using the organic solvent dichloromethane (CH2Cl2) that is also referred to as direct contact. Calcium carbonate (CaCO3) is used to remove the tannins from the coffee. Afterwards an extraction is used to separate the organic layer (bottom) from

    Premium Solvent Chemistry Caffeine

    • 873 Words
    • 4 Pages
    Good Essays
  • Good Essays

    The purpose of module E is to learn several DNA techniques in the lab including DNA purification with solubility and absorption‚ plasmid transfection of E.coli‚ colony screening by PCR and quantitative PCR. First part of the experiment E1 show the purification method of DNA through solubility. E. coli lysate mixed organic solvents to purify the DNA present in solution. First‚ the lysate was mixed with phenol/chloroform‚ then vortexed‚ and centrifuged. We extracted the aqueous layer and combined

    Premium Bacteria Escherichia coli DNA

    • 499 Words
    • 2 Pages
    Good Essays
  • Powerful Essays

    Title: Purification of Egg white protein Name: Michael Johnson Partner: David Logad & Nandita Date: 2nd – 9th September 2004 Group: Thursday 11:30am - 3:30pm Introduction Salting Out In 1888 Hofmeister that it can be possible to dehydrate a protein by adding salt to the solution‚ salting out. When a protein in a aqueous solution it is surrounded by water‚ in fact there can be up to 0.35g of water tightly bound to 1g of protein (Simpson 2004). Also the effectiveness of the salting out

    Premium Protein Egg white

    • 2864 Words
    • 12 Pages
    Powerful Essays
  • Good Essays

    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

    Free Caffeine Coffee Tea

    • 1109 Words
    • 5 Pages
    Good Essays
Page 1 9 10 11 12 13 14 15 16 50