paper chromatography (2)

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  • 1. GROUP 5 BS MLS 2-DDate Performed: November 10, 2012Date Submitted: November 16, 2012

2. Experiment No. 1 Paper ChromatographyI. Objectives1. To apply the principles involved in chromatography2. To practice chromatography in determining the solubility of an organic solute in different. 3. II. Flow Diagram of the Procedure 4. Discussing what should be doneCutting of Oslo Paper 5. Materials and Reagents 6. Grinding, Adding alcohol, Extracting of Leaves 7. Transferring of ExtractSpot on the oslo paperon the beaker 8. Set-up w/ eachPreparing the set-up Oslo paper 9. Observing 10. Finding the heightReturningof the solute and solvent the equipment 11. Chromatography is a techniquethat is used to separate and to identifycomponents of a mixture. In this lab experiment, weprepared 3 cut pieces of Oslo paper, leafextract and the set up place whereinthere should be ether with water on the1st test tube, toluene with water on the2nd and isopropyl alcohol with water onthe 3rd test tube. We have spotted theextract on the Oslo and place each insidethe test tube then we observed. 12. III. Results and Observation 1st TrialSOLVENT Maximum height Maximum height Rf Value of solute of solventEther 7.1 cm 7.1 cm1Toluene 7.2 cm 7.2 cm1Isopropyl 1.9 cm 3 cm0.63Alcohol 2nd Trial SOLVENTMaximum height Maximum height Rf Value of solute of solventEther 5.5 cm 5.6 cm 0.98Toluene 5.4 cm 5.4 cm1Isopropyl 1.5 cm 1.6 cm 0.94Alcohol 13. GUIDE QUESTIONS:1. Which solvent yields the highest Rf value? What does itindicate? This indicates that the spot is more strongly attracted to toluene than that of the paper. The solute is reabsorbed and displaced by the solvent, the higher the Rf value.2. Can Rf value be used to identify a substance in the mixture?Why? Yes. Because the movement of any spot on the paper can be qualified by calculating the Rf value . For this reason, substance in the mixture can be recognized and identified. Rf value is useful mainly for expressing the relative mobility of two or more solutes in a particular chromatography system.3. How are the components of a sample mixture separated andidentified in paper chromatography? Components of a sample are separated by passing them, through sheets of absorbent material. The key to the separation is that the different components of the mixture in each spot will rise at different rates, and so will be found to have reach different height on the paper. 14. IV.LearningsA.Values1. Teamwork must always be observed during the experiment.2. Selection of the right solvent combination for chromatography is the very important. Its also the most time consuming part of the process, so we must be patient.3. Keeping records will help you organize your data. 15. IV. LearningsB. ConceptsOne of the most effective technique for bothidentifying and separating mixtures is chromatography.Chromatography literally means color writing.Chromatography typically involves two phases onemoving phase (the mobile phase) through or the past, theother is the stationary phase. The technique takesadvantage of the fact that different components of themixture interact differently with two phases. Some will bestrongly attracted to (adsorbed onto) the stationary phase,while others will be more attracted (soluble in) to themobile phase. As the mobile phase moves through thestationary phase, the components more strongly adsorbedto the stationary phase will lag behind their more mobilecounterparts, thereby effecting a separation. 16. Chromatography of leavesMost leaves are green due to chlorophyll. This substance is important in photosynthesis(the process by which plants make their food). In this experiment, the different pigments present in a leaf are separated using paper chromatography.TEST TUBESTRIP OF CHROMATOGRAPHY PAPER SPOT OF PIGMENTSOLVENT (ETHER, ISOPROPHYL ALCOHOL, TOLUENE) 17. Performing a chromatographic experiment is basically a three-step process:1)application of the sample,2) "developing" the chromatogram by allowing the mobile phase to move up thepaper, and3) calculating Rf values and making conclusions.In order to obtain a measure of the extent of movement of a component in a paperchromatography experiment, we can calculate an "Rf value" for each separatedcomponent in the developed chromatogram. An Rf value is a number that is definedas: maximum height reached by the leaf extractmaximum height reached by the solvent 18. The distance traveled by the spot is measured to the MIDDLE of the spot.Max. height solvent reached 19. V. Application to Medical FieldAs a medical technologists, we canuse chromatography to : analyse drugs and also test blood and urine samples use it to separate and purify different substances chromatography can detect the presence of drugs in a persons blood used as a technique to separate the additives, vitamins, preservatives, proteins and amino acids 20. Prepared by:Mejia, May KimberlyGroup Leader Members: Mendoza, Syrah Mercado, Judy Ann Ortega, Jenny Rose Ortiz, Collen May Panganiban, Kathleen Panopio, Gabrielli 21. THANK YOU


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