"Rf values will be unique for each solvent. However, the general order of the Rf values should be the same because the more nonpolar pigments move farther in nonpolar organic solvents. A recent plant physiology manual (Reiss 1994) identifies six pigments from spinach leaves extracted with hexane and chromatographed with petroleum ether-acetone-chloroform (3:1:1) on silica-gl chromatography. The pigments and their Rf's were: carotene - 0.98 chlorophyll a - 0.59 chlorophyll b - 0.42 pheophytin - 0.81 xanthophyll 1 - 0.28 xanthophyll 2 - 0.15 The color of the bands can be a general guide to identify the pigments. Carotene is orange. Chorophylls are green. Chlorophyll a is a blue-green. Chlorophyll b is a yellow-green. Xanthophylls are yellow. Phaeophytin is chlorophyll lacking the central magnesium ion. Pheophytin is an olive-green."
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Oct 31st, 2014
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