Paper Chromatography Separation of Inorganic Cations

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1 - 46. When the solvent front on the chromatogram is approximately 1 cm from the top,remove the paper. Mark the solvent front quickly with a pencil (before the solventevaporates and you can no longer see where it was). Allow the chromatogram to dry(you can use an oven set at 60 o C). Circle the visible spots and record their colours inon your report (Table 1). Not all the spots will be visible at this stage, the variouschemical treatments in the next steps will help show where they are.7. Working in a fumehood, place your dried chromatogram in a closed dessicatorcontaining a beaker containing 6M ammonia solution for 2 to 3 minutes. You may seefumes arising from the paper, the ammonia is neutralizing any residual HCl on thechromatogram. Circle any new spots that appear and note their colours. Record yourobservations in Table 1.8. In a fumehood, spray the chromatogram lightly with a 1% solution ofdimethylglyoxime (DMG) - do not soak the paper completely. Circle and record thecolours of any new spots. If no new spots are visible, hold the paper over ammoniaagain as in step 7. Dry the chromatogram in an oven. Be careful not to char the paper.9. Finally, working in a fumehood, spray the paper lightly with a solution of 0.5% oxine(8-hydroxyquinoline) solution. Circle any new spots and record any colour changes tothe spots.10. Dry the chromatogram and calculate the R f values of each spot and that of yourunknown. Record your values in Table 2.
1 - 5Experiment 1 - ReportName_______________________________________Date________________________Unknown #’s__________________________________Questions:1. What is the structure of the stationary phase (cellulose)?2. What species are likely to exist in the moving phase (water/hydrochloricacid/acetone)?3. What is the nature of the attractions between the stationary phase (cellulose) and themoving phase (hydrochloric acid/water/acetone and the species being separated.4. What is the effect of the ammonia, dimethylglyoxime and oxine that leads to some ofthe colourless spots becoming visible?
Page 1 and 2: 1 - 1EXPERIMENT 1Paper Chromatograp
Page 3: 1 - 3Figure 2: Folding the paper fo
Page 7: 1 - 7ConclusionsWhat ions were pres

Paper Chromatography Separation of Inorganic Cations

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