Biology Report

Chromatography of Plant Pigment And Photosynthesis

Part A: Chromatography of Plant Pigments

Introduction

Paper chromatography is a technique used to separate a mixture into its component molecules. The molecules of the solution move freely up the chromatography paper at different rates because of the differences in solubility and hydrogen bonding with the paper. The purpose of this lab is to observe the separation of plant pigments (in this case, spinach leaves) using chromatography and to calculate the rate of photosynthesis (Rf value) for the spinach pigment. Hypothesis: As the time elapsed, the pigments have traveled up the chromatography paper until its end and the distance results have been obtained.

Materials and Methods

Chromatography vial was obtained and labeled with initials. In a well ventilated area, the cap was removed and with a disposable pipette 1ml of chromatography solvent was added. The vial was closed and placed aside to ensure the atmosphere is saturated with solvent vapors. Chromatography strip was given to each group and the groups measured 1.5 cm from the end, drew a line across and formed a pointed end with scissors. A fresh piece of spinach leaf was rubbed with the edge of the coin to ensure the different portions of spinach pigments are traced on chromatography paper. The chromatography strip was placed in the vial and was left undisturbed. After solvent reached approximately 1 cm from the top, the strip was taken out of the vial and marked the location of the solvent front. Once the strip has dried, the middle of each pigment was marked. The distance was measured from the original spinach extract line to each middle mark on the strip. Rf values were calculated by the use of the following formula:

Rf = Distance pigment traveled

Distance solvent traveled

Results

Results are listed below.

Band Number | Pigment |...