Chromatography of Photosynthetic Pigments
In this experiment a process of chromatography was used to separate chlorophyll a, chlorophyll b, xanthophyll, and beta carotene. When these pigments were obtained they were used to measure the wavelengths by way of spectrophotometer of each and the total of all the pigments wavelength. Introduction
Photosynthesis is a process by which plants use the sunlight to convert it from light energy into chemical energy. This equation shows us how it is done, 6CO2 + 6H2O + light energy --> C6H12O6 + 6O2. The pigments called chlorophylls in the plants are what trap the light energy. Carotenoids also help aid the chlorophylls by also absorbing light. The two chlorophylls found in green plants are chlorophyll a and chlorophyll b. The purpose of this lab is to extract the pigments from spinach leaves and separate them by using chromatography to determine each of the pigments absorption spectra. Methods and Materials
For this experiment I used a 10mL pipette, a 100mL graduated cylinder, a rubber stopper, chromatography paper, forceps, cuvettes, spinach leaves, hexane-acetone, acetone, and the spectrophotometer to record the wavelength.
To start the experiment I first pipette 10mL of hexane-acetone into a 100mL graduated cylinder and put the rubber stopper on to prevent any of the solution from evaporating. While letting the hexane-acetone set I then prepared my chromatography strip but first cutting it to 20 centimeters and then cutting one end to a point. Then I used 2-3 spinach leaves and a quarter to leave a green residue line containing the pigments of the spinach leaves. I then inserted the strip with the spinach pigments into the cylinder I prepared earlier with the hexane-acetone. When the chromatography strip was properly into the cylinder I then put the rubber stopper onto the cylinder checking the progress of how far the solvent moved every 5 minutes. After 20 minutes the solvent reached to about 1 cm...
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