1 Paperchromatografie of chlorophyl

Material:

  * Some leaves
  * Mortar met pestle
  * (Clean silversand)
  * aceton?
  * petroleumether 40-60°C?
  * liquid (petroleumether 40-60°C - aceton 9:1)
  * chromatograficpaper
  * capillair
  * pencil

·        Do everything in a fire free room .
  * Put the leave partikels in the mortar.


  * Add a little silversand and polish them.
  * Add a little aceton.
  * Polish again until a green liquid arises. (extract).
  * Take  a slip of chromatografiepaper.
  * Just touch the edges. (not the whole paper with your fingers)
  * Draw a line down below at 2 cm of the edge with a pencil (= startline)
  * Put the filtreerpapier on a clean background and draw with the capillair a line of chlorophyll
on the start line


2

  * Dry the spot with a föhn. Repeat this 10 to 20 times.
  * Try to keep the spot as small as possible.
  * Pour the liquid (acetone/ petroleum) into a cilinder glas. Not more than 1.5 cm high.
  * Hang the paper on the cork with the bottom in the liquid
  * De chlorophyll spot must be above the liquid and the edges of the paper must not touch the side
of the glass.
  * When the liquid is almost above (after 25 minutes), remove the chrmomatogramme
  * Mark with the pencil the front and the place of the coloured spots.

The distance (rF-value) is calculated for every spot by dividing  the distance (A) by the distance
between start and front(B).De rF- value is by a certain T and a certain liquid characteristic for a
matter. The rF- values of the chlorophyll can be looked up.

What is Rf value?:  It is the distance travelled by the sample or analyte divided by distance
travelled by the solvent front in chromatography. For example, if a compound travels 2.1 cm and the
solvent front travels 2.8 cm, the R[f] is 0.75 The R[f] for a compound is a constant from one
experiment to the next only if the chromatography conditions below are also constant:
  * solvent system
  * adsorbent
  * thickness of the adsorbent
  * amount of material spotted
  * temperature