Chromatography Lab Report Example | Topics and Well Written Essays - 1500 words

Chromatography - Lab Report Example Unknown mixtures of dyes were also resolved into their respective components using paper chromatography. Chromatography is a separation technique that determines the components of a mixture. Drug tests of blood and urine samples as well as determining the presence of harmful substances in drinking and groundwater are the most common uses of chromatography. The solid or liquid stationary phase holds the mixture to be separated. In addition, it is the medium to which the mobile phase passes through. On the other hand, the liquid or gaseous mobile phase passes along the stationary phase and in the process carries the components of the mixture with it. In the end of the experiment, separate bands are observed, representing the different components that move along the stationary phase at different rates. The chromatogram is the pattern of separated bands produced after chromatography. Each band is characterized by its retention factor, which is the ratio of the distance between the origin line and the band of the component and the distance between the origin line and the solvent front. In paper chromatography, a specialized paper made of cellulose is used as the stationary phase. The best mobile phase for a particular separation experiment depends on which solvent system the sample components have different Rf values. Thus, measurement of Rf values of the individual sample components in a variety of solvents is necessary in deciding which solvent to use as the mobile phase. This experiment was conducted to determine, through paper chromatography, the retention factors (Rf) of the seven pure food dyes, red 3 (R3), red 40 (R40), blue 1 (B1), blue 2 (B2), yellow 5 (Y5), yellow 6 (Y6), and green 3 (G3), approved by the Food and Drug Administration (FDA) and dissolved in three different solvent systems, distilled water, 70% isopropyl alcohol, and 0.10% sodium chloride (NaCl)