Chromatography Lab

The intermolecular forces are pulling the molecules between the stationary phase, the chromatography paper and the mobile phase, the solvent. The molecules of the chromatography paper are trying to pull the molecules to where they are while the molecules of the molecules with them to the top of the paper. 4. Draw a picture of how the chromatography worked. Explain your picture using the following terms: stationary phase, mobile phase and intermolecular forces.

If you put too much of a sample on your chromatography paper, you could possibly have that color bleed into the color next to it, which would mess up your results. If you put too little of a sample on the paper, your color

Which one of the statements concerning valence bond (VB) and molecular orbital (MO) bond theories is correct?

Answer: Once the chromatogram has been completed and is ready to be measured and calculated, on the plate that was used to perform the chromatogram you should see where the red and blue have completely separated. The red food coloring dye should be lower on the plate than the blue food coloring dye.

On a thin chromatography plate, five spots were placed ( as shown in table 2) and the plate was developed using chloroform/methanol. This was later visualized with dragendorff’s reagent under the UV light. All separated components were observed, identified and recorded.

Sephadex chromatography (gel-filtration chromatography) separates molecules on the basis of their size. It is a form of column chromatography in which the stationary phase consist out of cross-linked gel particles. The gel particles are usually in bead form and consist of agarose. Molecules of varying size move through a bed of permeable beads, diffusing into the beads. Small molecules are able to diffuse further into the pores of the beads, thus these smaller molecules move through the bed slowly. Large molecules do not enter or enter less and thus move through the bed faster or quickly. Sephadex chromatography may be used for the determination of molecular size, for the separations of specific components in a mixture, or for preparation of macromolecules.

Aim The objective of this experiment was to separate a mixture of two compounds (ferrocene and acetylferrocene) using adsorption column chromatography. Introduction Adsorption column chromatography is a technique that uses a solid stationary phase which is fixed and a liquid mobile phase that moves slowly through the packed column. This technique uses the property of polarity as the compounds have a greater affinity towards the respective phases (either stationary or mobile) which leads the compounds moving at different rates through the packed column and separating from one another.

     After the column the separated compounds enter the detector, which measures a physical or chemical property of each, now relatively pure, compound and creates a proportional electronic signal. By calibrating with a standard mixture of known compounds, the nature of the compound in the

Repeat steps 1-8 using .093 g Azo Grenadine dye. Complete 7 trials for each dye As predicted in the hypothesis a color change did occur, accompanied by effervescence. The color change appeared to take place at a more rapid pace towards the beginning of the trial. This was likely due to the fact that the rate of the color change would be expected to slow as the concentration of the original solution decreased as the dye molecules were oxidized or fragmented. The solution faded from a deep red to an orange color and finally to the control yellow.

This would improve the quality of the chromatograms, as the bands produced would be less faint, as in Chromatogram B, where the bands are only just distinguishable, especially through a photograph. The chromatograms in both the paper and thin-layer chromatography could also be improved by using a larger stationary phase. A larger piece of paper or thin-layer plate would increase the surface area of the stationary phase, and give the mobile phase, made up of solvents, more time to travel up the stationary phase. This would allow the pigments within the sample of plant extract to spread out more, and also give more accurate Rf values. To produce more accurate results and improve the chromatograms produced, the chromatography method could have been repeated three times for each investigation, for example three paper chromatograms with acetone as the mobile phase, and three with the mixed solvents, and then three thin-layer chromatograms with the mixed solvent as the mobile

In GC the mobile phase is a gas and the stationary phase is a solid in column form (generally metallic or glass tube), in this type of chromatography the analyte must pass through the high pressure gas cylinder (mobile phase) this analyte will then being to react with the walls of the column containing the stationary phase and depending on the attraction each compound has with this stationary phase it will elute at different times, i.e. The retention time.

So as long as the correct solvent and type of chromatography paper are used, a component can be identified from its retention

The following procedure dealt with a chromatogram. The materials needed are: a pencil, safety goggles, scissors, chromatography paper strip, capillary tube, spinach plant pigment extract, test tube, cork stopper, graduated cylinder, chromatography solvent (alternative isopropyl alcohol), metric ruler, stopwatch or clock with a secondhand, hook/fashioned paperclip, paper towels, test tube rack, and mortar and pestle. First we obtained a strip of chromatography paper and cut it so it would fit inside a test tube (with it barely touching the bottom of the tube). Also, when touching the strip, touch the sides only. Then we attached (firmly) the top of the strip to a hook (or fashioned paperclip at bottom of the cork stopper). Make sure it fits in the test tube. Next we used the pencil to draw a faint line across the strip two centimeters from the bottom tip of the strip. We placed the cork and strip in place, and we put a mark on the test tube one centimeter below the top of the stopper.

Chromatography Investigation Chromatography is a highly regarded technique used to separate the components of a mixture. It is based on the principle that each component possesses a unique affinity for a stationary phase and a mobile phase. The components that are more inclined to enter the mobile phase will migrate further on the chromatogram and distinguish themselves from the other components. The type of solvent used in chromatography is known to directly affect the separation of the mixture. In this experiment, thin-layer and column chromatography will be utilized to separate the numerous chlorophyll and carotenoid pigments of a spinach extract.

There are terms brought about like the “capillary action” which pertains to the capillary property of water in reaction to the substance. There are also terms like “Retention factor value” meaning the distance run by a component spot, divided by the distance run by the solvent in thin layer chromatography. Also