4. After the propan-2-ol has turned dark green, pour the propan-2-ol into a 100cm^3 glass
beaker.
5. Take a thin strip of chromatography paper and draw a line with a sharp pencil gently and
a ruler across the paper on the mat side. 1cm from the bottom. Draw a small ‘x’ in the
centre of the line.
6. Using a capillary tube, take up a small amount of the green solution from the 100cm^3
glass beaker and drop a suitable amount of sample onto the small ‘x’. Allow the drop to
dry for 30 seconds.
7. Add another drop onto the first one and allow another 30 seconds drying time before
adding a third drop.
8. Repeat steps 1-7 for your other leaf.
9. Hang the chromatography papers inside the 500cm^3 glass beaker so that the bottoms of
the papers are 1-2mm from the bottom of the beaker. Secure the papers by placing
bulldog clips on the top of the papers and sliding a spatula through the arms of the clips.
If the papers are too long, fold them on the top end until the papers are the correct length.
Take the papers out of the beaker and place carefully on one side.
10. Add a small amount of propan-2-ol to the 500cm^3 beaker. The solvent should be no
more than 3-5mm deep.
11. Carefully add the papers back into the beaker so that the propan-2-ol touches the bottoms
of the papers. The propan-2-ol should not be above the line drawn on the chromatography
paper.
12. The propan-2-ol should start to move slowly up the chromatography papers by capillary
action, separating out the pigments.
13. After 30 minutes, take the chromatography papers out of the beaker and allow them to
dry.
Figure 6: The displayed chromatographic technique for extracted pigments
, Figure 7: The produced paper chromatograms. The mobile phase is propan-2-ol
Figure 8: The calculated Rf values
EQUIPMENT LIST:
Leaves from two different plants
Propan-2-ol
Capillary tubes
10cm^3 measuring cylinder
Sharp pencil
Spatula
Scissors
beaker.
5. Take a thin strip of chromatography paper and draw a line with a sharp pencil gently and
a ruler across the paper on the mat side. 1cm from the bottom. Draw a small ‘x’ in the
centre of the line.
6. Using a capillary tube, take up a small amount of the green solution from the 100cm^3
glass beaker and drop a suitable amount of sample onto the small ‘x’. Allow the drop to
dry for 30 seconds.
7. Add another drop onto the first one and allow another 30 seconds drying time before
adding a third drop.
8. Repeat steps 1-7 for your other leaf.
9. Hang the chromatography papers inside the 500cm^3 glass beaker so that the bottoms of
the papers are 1-2mm from the bottom of the beaker. Secure the papers by placing
bulldog clips on the top of the papers and sliding a spatula through the arms of the clips.
If the papers are too long, fold them on the top end until the papers are the correct length.
Take the papers out of the beaker and place carefully on one side.
10. Add a small amount of propan-2-ol to the 500cm^3 beaker. The solvent should be no
more than 3-5mm deep.
11. Carefully add the papers back into the beaker so that the propan-2-ol touches the bottoms
of the papers. The propan-2-ol should not be above the line drawn on the chromatography
paper.
12. The propan-2-ol should start to move slowly up the chromatography papers by capillary
action, separating out the pigments.
13. After 30 minutes, take the chromatography papers out of the beaker and allow them to
dry.
Figure 6: The displayed chromatographic technique for extracted pigments
, Figure 7: The produced paper chromatograms. The mobile phase is propan-2-ol
Figure 8: The calculated Rf values
EQUIPMENT LIST:
Leaves from two different plants
Propan-2-ol
Capillary tubes
10cm^3 measuring cylinder
Sharp pencil
Spatula
Scissors
