Chromatography Lab Report

Materials and Methods:

For the chromatographic separation of plant pigments, pieces of spinach were ground with acetone to produce a watery extract. A line of extract was applied 1 cm from the bottom of a strip of chromatography paper. The line dried and the extract was reapplied. Once that dried, the paper was placed into a jar containing a small amount chromatography solvent (small enough that the line was not drowned by the solvent) which is made of 1 part acetone and 9 parts petroleum ether. The lid was placed on the jar and was only removed once the pigments had separated and the solvent had almost reached the top. The distance travelled from the original line or extract to the separated pigments was then measured and recorded on a table

Chlorophyll A, Chlorophyll B, carotenes, anthocyanins and xanthophylls (a carotenoid) are the most important. Chlorophyll A should be represented by a blue-green color, Chlorophyll B should be represented by a yellow-green color, carotenes should be represented by an orange or yellow color, xanthophylls should be represented by a yellow color and anthocyanins should be represented by bright colors sort of like fall leaves (pink, purple and red). The results that were obtained from the experiment show the presence of Chlorophyll A, Chlorophyll B, carotenes and xanthophylls, but does not show the presence of anthocyanins. Some sources of error for this experiment could have been improperly placing the mixture of acetone and leaves on the chromatography paper, drowning the chromatography paper in the chromatography solvent or leaving the paper in the solvent for too long of a time frame. This experiment allows us to view the different components of plants and demonstrates how useful chromatography is in identifying the parts that make up a

Photosynthesis is dependent on light and the more light a pigment can absorb, the faster photosynthesis can occur. This is helpful information because it gives us a good idea in regards to what wavelength of light a plant should be exposed to if the maximum efficiency of photosynthesis is desired. Some sources of error in this experiment could include not properly calibrating the spectrophotometer after each measurement, not getting enough of the pigment into the mixture with the acetone or improperly reading and calculating the values off of the