Lab Report On Chromatography And Lab

After analyzing the results of the paper chromatography, the next step was the determination of the absorption spectrum for the spinach leaf pigments chlorophyll a, chlorophyll b, xanthophyll, and carotenoids. The amount of absorbance was determined with the help of the spectrophotometry, which quantitatively measured the fraction of the light passing through each pigment extract solution, indicated on the absorbance scale. The wavelength was increased every 20-nm, starting with 400-nm, and reaching 740-nm. The results are shown in Table 1 and Table

In this chromatography lab filter paper was used to examine the different pigments of spinach and red cabbage. There were two hypotheses for both plants. The hypothesis for the red cabbage was that there would be multiple pigments evident. The hypothesis for the spinach was similar in that there would be different pigments present. Both hypotheses were accepted in that there were multiple pigments found on the filter paper of each sample.

In the beginning of this experiment, our TA added water, salt, and 75/25 hexane/acetone to spinach leaves to a blender and blended the mixture to assume equal amounts for each group and to avoid erros if each student had to do the blending. The addition of the water to the mixture allowed the it to separate into a distinct organic layer after being run in a centrifuge, which was available to be collected at the top of the centrifuge. Salt reduces solubility, which will force the organic parts of the mixture (the desired pigments for example) to separate into the organic layer at the top. Lastly, 75/25 hexane/acetone is added because this is a moderately polar solvent and will useful for both the non-polar and polar pigments present within the spinach leaves. A mixed solution of hexanes and acetone must be used because acetone is very polar, while hexane in very non-polar, and the spinach leaves contain both non-polar and polar pigments in them that are important in the extraction and for further analysis. The mixture was placed in the centrifuge so the solids in the mixture (mostly cellulose) could be separated from the liquids into separate distinct layers for further extraction and testing. In the tube, the organic substances separated into the top layer, whereas the water layer remains at the bottom of the tube below the solid layer made up of mainly cellulose.

The importance of Chromatography is for the separation of compounds in a mixture. The separation happens between the stationary and the mobiles phases. This experiment itself is based on the non-covalent interactions between the stationary phase, the different compounds and the solvent.

The pigments of fresh, frozen and canned spinach were extracted by grinding the mixture until observing a powder-looking appearance. The sand was used to destroy the cell walls of spinach and free the pigments while any traces of water were being removed by the drying agent (MgSO4). Following this, the mixtures were transferred to three labeled test tubes in which 2.0 mL of acetone were added to each. The acetone washes the photopigments from the cells and cytoplasm. In this manner, using a fixed speed vortex mixer, the mixture was shaken vigorously for 10 minutes.

The procedure for this lab was to punch 30 uniform leaf disks in several spinach leaves, label three plastic cups with: Light, Ambient Light, and Dark. Then prepare a 0.2% solution of sodium bicarbonate and water in a larger beaker and add 2 drops of liquid soap to the solution. Remove the plunger from the syringe and place 10 leaf disk into the syringe. Insert the tip of the syringe into the solution and draw 15-20mL into the syringe. Then seal the tip of the syringe using your index finger and the leaf disk should began to sink.

In this paper, the author want to know whether human genetic patents affect subsequent scientific research and product development. They use the administrative data on successful and unsuccessful patent applications filed with the USPTO and then link the exact gene sequences required for each application with subsequent scientific research and business investment data. By using these data, they found patented genes have more valuable prior to being patented than non-patented genes. They used two quasi-experimental approaches to text their hypothesis. In the end, they found both of the approaches suggest that on average gene patents have had no effect on follow-on innovation. “This evidence of selection motivates two

Once the application of the spinach extract was finished, acetone, the solvent, was poured into the beaker. Then the cylinder was placed into the beaker to absorb the solvent with a jar top placed on top of it to hold it in place. The chromatography cylinder stayed in the beaker until the pigments in the spinach extract had been separated into different colors and was about 4-5 cm from the top of the paper. After this, the chromatography cylinder was removed to dry for the different pigments could be observed.<p>

The purpose of this experiment was to take spinach leaves and extract the chlorophyll and carotenoid pigments by using acetone as the solvent. The chlorophyll and carotenoid pigments were extracted by using column chromography and alumina was used as the solvent. Solvents of different polarities were used, starting with the least polar, to extract the certain components from the leaves. They were then analyzed by using thin- layer chromatography.

Goal: The first goal of today’s laboratory is to separate components of spinach dyes using different eluants. The four eluants will be using are ethanol, chloroform, 9:1 petroleum ether : ethanol, and petroleum ether. The second goal of the lab is to separate fluorine and fluorenone by column chromatography. Thin layer chromatography (TLC) was used to measure the polarity and separate the components in the mixtures. TLC was chosen because of its simplicity, high sensitivity, and speedy separation. For each part of the lab, we measured the retention factor on the TLC plate. To measure the retention factor, we used the formula:

The separation of the spinach is caused by each compound’s solubility and its adsorption to the silica gel. Each compound is dissolved in the solutions to a different extent, and they travel with it as it moves up the TLC strip. The compounds will be attracted to the OH groups on the silica’s surface if they are polar, causing more polar molecules to move more slowly up the strip. The compounds are separated when they all move at different speeds up the TLC.

The solvents that were used in the column chromatography were hexanes, 75/25 hexanes/acetone solvent, and acetone. The adsorbent used in the column chromatography was alumina, which is polar. All of the pigments moved through the column based on their polarity. Hexanes were used because they are nonpolar due to their hydrocarbon chain and was used as the initial solvent before the extract was placed in the Pasteur pipette. Carotene, which is nonpolar hydrocarbon chain, was the first pigment extracted. The nonpolar solvent was used because it is soluble in the nonpolar carotene, thus moving it through the column quickly. To elute the next pigment of chlorophyll the solvent was the hexane acetone mix. This mixture is slightly more polar because

Lab Report Assistant This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable file which can be sent to an instructor.

This experiment focus on pigments quantification from chloroplast. Pigments are extracted from frozen chloroplasts extracted from barley leaves. Dilution was made using buffer. In order to get final concentration acetone (100%) was added into each dilution. Thereafter total concentration of pigments is determined

In this lab, a few pieces of spinach were grinded to extract all of the pigment molecules from the leaves. The extract was then put through a piece of filter paper to filter out the large bits of spinach. The extract was then put in a microcentrifuge to help separate the pigment molecules from any larger pieces left in the extract. The extract was placed on a single spot on a piece of filter paper. The filter paper was then placed into a chromatography solvent to separate the pigment molecules further. The distance that the pigment molecules went were measured, and then the Rf for each were found. It was found that the leaves of spinach used contained the following pigments; xanthophyll 2, chlorophyll a, and beta-carotene. The pigments xanthophyll 1 and chlorophyll b were not found in this experiment, most likely due to an error in the technique or procedure. Furthermore, the hypothesis was found to be partially accurate due to the fact that chlorophyll a, xanthophyll 2, and beta-carotene were found, but chlorophyll b and xanthophyll 1 were not found. The Rf found experimentally for xanthophyll 2 was 0.15, and the actual Rf is 0.15, which means that there was a zero percent error. The Rf found experimentally for chlorophyll a was 0.52, but the actual Rf is 0.59, which indicates there is twelve percent error. Finally, the Rf found experimentally for beta-carotene was 0.84, but the actual Rf is 0.98, which indicates that there was a fourteen percent error. The Rf