Paper chromatography is an important separation technique that depends upon differences in how strongly the dyes are adsorbed onto the paper (stationary phase) and how soluble the dyes are in the developing solvent (mobile phase). In paper chromatography, a small amount of the mixture to be separated is placed close to the edge of a piece of paper. The edge of the paper is then immersed in a developing solution. As the developing solution ascends up the paper by capillary action, the. components of the sample are carried along at different rates. Each component of the mixture will move a definite distance on the paper in proportion to the distance that the solvent moves. The dyes travel different distances because they all have different polarities – that is, the atoms in some dye molecules share their electrons more unequally than in others. The more polar dyes are more attracted to the stationary phase and thus aren’t carried as far by the mobile phase, while the more nonpolar dyes have less affinity for the paper and are carried further by the rubbing alcohol. It is important to use alcohol because water has a different polarity than alcohol, so if we were to use water instead of alcohol, the dyes would have different relative affinity for the mobile phase, which would affect how far those components would travel along the paper.
According to data the guilty party is Mr. Bunsen because after comparison of all experiments with the unknown sample, Mr. Bunsen’s Rf calculations were the closest to the Rf calculations of the unknown. In our sodium hydroxide solution the compounds that were chromatographed were separated the furthest and produced Rf calculations for all of the suspects except Ms. Buchner. Changing the solvent allowed us to have a better resolution of the separated components. Acetic acid separation for the samples were very small sodium chloride solution was also similar to Acetic acid. Conclusion
The unknown of NaCl and Acetic...
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