Prepare one 10-CM x 4. 3 CM TTL with four marks for spotting. Prepare four microscopes to spot the plates.
Prepare a chromatography column packed with alumina. Place a lose plug of ton in a Pasteur pipette and push it gently into a position using a glass rod. Using a file, score the Pasteur pipette about 1 CM below the cotton plug. To break the tip off the pipette, put your thumbs together at the place that scored and push quickly with both thumbs. Add 1. 25 g of alumina to the pipette while tapping the column gently with your finger.When all the alumina has been added, tap the column with your finger for several seconds to ensure that the alumina is tightly packed. Clamp the colon in a vertical position so that the bottom of the column is just above the height of the est.
. Tubes you will be using to collect the fractions. Place test tube 1 under the column. Running the column. Using a Pasteur pipette, add 3 ml of hexane to the column. The column must be completely moistened by the solvent.
Drain the excess hexane until the level of hexane reaches the top of the alumina.Once hexane has been added to the alumina, the top of the column must not be allowed to run dry. When the level of the hexane reaches the top of the alumina, add the solution of fluorine and fluorine tot eh column using a Pasteur pipette.
Begin collecting the element in test tube 2. Just ass the solution penetrates the column; add 1 ml f hexane and drain until the surface of the liquid has reached the alumina. Add another ml of hexane.
As fluorine lutes off the column, some solvent will evaporate, leaving solid fluorine on the tip of the pipette.Using a Pasteur pipette, dissolve this solid off the column with a few drops of acetone. After you have added all the hexane, change to the more polar solvent (70% hexane-30% acetone). When changing solvents, do not add the new solvent until the last solvent has nearly penetrated the alumina.
The yellow band (fluorine) should now move down the column. Just before the yellow band reaches the OTTOMH of the column, place test tube 3 under the column. When the element becomes colorless again, place test tube 4 under the column and stop the procedure.Tube should contain fluorine and tube 3, fluorine. Test the purities of these samples using the TTL. You must spot the solution fro tube 2 several times in order to apply enough sample on the plate to be able to see the spots.
Using a warm water bath and a stream of nitrogen gas, evaporate the solvent from test tubes 2 and 3. As soon as all the solvent has evaporated from each of the tubes, remove them from the water bath. Determine the melting points of fluorine and fluorine.