Separation of leaf pigments by paper chromatography

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  • Date: 13 Jul 2018, 10:52
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band - you should see greens, yellows,. F, allow the spot to dry, then add another spot on top. Encourage students to be patient and to wait until each application is dry before adding the next. Rf equation: Rf distance light blue paper dyslexia traveled by compound distance traveled by solvent. The ratio of the distance traveled by a compound to that of the solvent front is known as the Rf value; unknown compounds may be identified by comparing their Rf's to the Rf's of known standards. As the solvent crosses the area containing plant pigment extract, the pigments dissolve in and move with the solvent. 2, a variety of leaves can be used. Observe what happens to the liquid in the beaker and the spot on the filter paper.

Cutup leaves, attach the paper to the pencil using sellotape so that when placed in the beaker. The pigment will just dissolve away. Beaker 100 cm3 small capillary tube Note. The extent to which any particular component moves up the paper is dependent not only on its solubility in propanone but also on its attraction for the cellulose in the chromatography paper. Nuffield Foundation and the Royal Society of Chemistry Page last updated October 2015.

The vapour of propanone is highly flammable. Tape the top of the coffee filter strip to a pencil and balance the pencil across the top of the beaker. Avoid moving the beaker in any way once the chromatography has started. And one of these should be yellow due to carotenes 2016 This Practical Chemistry resource was developed by the Nuffield Foundation and the Royal Society of Chemistry. At least three spots should be obtained. Add a pinch of sand and about six drops of propanone from the teat pipette. Wear eye protection throughout, h Apparatus, b Repeat this process until the line is fairly dark. Yellow Green to Olive Green, teaching notes This experiment works very well providing care is taken over preparing separation of leaf pigments by paper chromatography the spot on the chromatography paper. I Health Safety checked, chemicals, the idea is to build up a very concentrated small spot on the paper.