Introduction: Chromatography is a technique used to separate small quantities of mixtures into its individual components. This is done by distributing the components between two phases: stationary and mobile. The stationary phase is the system in which the materials to be separated are absorbed. The mobile phase is the mixture of solvents that flows through the stationary phase. Separation for each substance is based on the different affinities each has for each phase, low affinity for moving phase and high affinity for stationary phase. Both of these experiments work based on polarity differences between components in the sample.
In this lab there were two chromatography experiments, food color paper chromatography and amino acid thin layer
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This mixture was then poured into a chromatography jar and its lid closed. The liquid mixture was swirled to mix the developing solvent components. Then using 10 cm x 5 cm sheet of Whatman silica gel flexible plate a 5-cm-long line about 2 cm up from the short edge of the sheet was drawn with a pencil. Then using a centimeter ruler four small marks were measured at 1 cm intervals along the line on the short part of the silica gel plate. Then the amino acid solutions; glycine, alanine, phenylalanine and the unknown 936, were spotted from left to right on the marks made. After the spots were dried it was placed inside the chromatography jar. When the solvent had moved within 1- 2 cm from the top of the silica gel plate, it was removed and the location of the solvent was marked with a pencil. Then the chromatogram was placed to dry again. When the chromatogram had dried it was sprayed with a ninhydrin solution under the fume hood. This solution helped visualize the pink spots of colors on the paper. Then the location of each amino acid was outlined with a pencil and the composition of the unknown was determined using the calculated Rf …show more content…
The Red 3 dye traveled the farthest reaching almost the same distance as the solvent front. This was probably because it was a nonpolar compound like the mobile phase. The Food Color Green and Food Color Blue traveled the same distance, 14 mm, this was probably due to them being very similar in their chemical structure.
In the amino acid thin layer chromatography, the unknown 936 amino acid was determined to be Phenylalanine. This was because it had traveled the same distance as Phenylalanine. Both of these were the only ones in the chromatogram that traveled the farthest in the silica gel plate. All the amino acid tested showed a pink color in the chromatograph.
The results showed that polarity of the solvent was the deciding factor in determining how far each compound would travel. If the mobile phase was non-polar then the non-polar compounds would travel farther up than the polar compounds. If the mobile phase was polar, the polar compounds would travel farther up than the non-polar compounds. The thin-layer chromatography was polar and the paper chromatography was
The purpose of the Unknown White Compound Lab was to identify the unknown compound by performing several experiments. Conducting a solubility test, flame test, pH paper test, ion test, pH probe test, conductivity probe test, and synthesizing the compound will accurately identified the unknown compound. In order to narrow down the possible compounds, the solubility test was used to determine that the compound was soluble in water. Next, the flame test was used to compare the unknown compound to other known compounds such as potassium chloride, sodium chloride, and calcium carbonate. The flame test concluded that the cation in the unknown compound was potassium. Following, pH paper was used to determine the compound to be neutral and slightly
To uncover organic compounds like carbohydrates, lipids, proteins and nucleic acid, by using tests like Benedict, Lugol, Biuret and Beta Carotene. Each test was used to determine the presents of different organic molecules in substances. The substances that were tested for in each unknown sample were sugars, starches, fats, and oils. Moreover, carbohydrates are divided into two categories, simple and complex sugars. Additionally, for nonreducing sugars, according to Stanley R. Benedict, the bond is broken only by high heat to make make the molecules have a free aldehydes (Benedict). As for Lipids, there are two categories saturated and unsaturated fats. One of the difference is that saturated fats are mostly solids and have no double bond (Campbell Biology 73). The Beta Carotene test works by dissolving in a lipid, thus giving it color to make it visible. Moreover, proteins are made out of amino acids that are linked by a polypeptide bond (Campbell Biology 75). The purpose of this experiment was to determine whether an unknown class sample or food sample had any carbohydrates, lipids, or proteins in it. The expected result of the lab was that some substances would be present while other would be absent.
The objective of this experiment was to perform extraction. This is a separation and purification technique, based on different solubility of compounds in immiscible solvent mixtures. Extraction is conducted by shaking the solution with the solvent, until two layers are formed. One layer can then be separated from the other. If the separation does not happen in one try, multiple attempts may be needed.
A convenient method of separating a mixture of organic compounds is recognized as liquid-liquid extraction, which involves the dispersion of a substance between two immiscible solvents using preferential solubility. Strategically using the differences in solubility of the interested solute, the compound can be transferred from one liquid part to the other during extraction. Organic acids and bases can be separated from each other by using an organic solvent like diethyl ether and a polar solvent such as water. Diethyl ether is an appropriate solvent since it wil...
Many advertisements sometimes mislead its consumers when selling out protein powder products. One particular manufacturer is claiming that when testing 1 gram of Tough Guy protein powder in 100 ml of H2O, the final concentration would measure between 0.40 mg/ml protein. To determine if the manufacturer is claiming to be true or not an experiment was conducted. By determining the amount of protein that is presented when Tough Guy protein powder is diluted in water by adding Bio-Rad assay (measuring the concentration of protein within a known and unknown samples). Measurement of color change will be needed by placing the solution into a spectrophotometer at 595 nm. Thus, determining its results.
Separations are important techniques in chemistry that are used to separate various components of a mixture. They are carried out by mixing two immiscible liquids containing certain solutes together in a separatory funnel, allowing them to separate, then extracting the distinct layers that form. The ratio of the concentration of solute present in the upper layer to the concentration in the lower layer is called the partition coefficient. The efficiency of a separation is described by this partition coefficient. If the coefficients for the two layers are largely different, then the separation can be carried out in a single step. If they aren’t, a more complex process is necessary.1,2 Countercurrent chromatography is a technique used carry out separations in these kinds of cases. It uses a continuous liquid-liquid partitioning process to streamline the usual extraction procedure.
In this laboratory, the degree of absorbance for the pigments in a leaf sample were observed using mechanisms that involved pigment isolation from a leaf extract, obtaining wavelength measurements, and displaying the measurements on an absorption spectra.
[IMAGE][IMAGE][IMAGE] As Iodine indicates the symbol means irritant (harmful). Therefore I will be careful with this chemical that it doesn’t get to my skin. 6) Chemicals should be placed in the tray so that if they spill they don’t drop all over the place and accidents from occurring could be stopped. Apparatus: The apparatus that I require for this investigation is: 1) Test tubes (4): These will be used to place the amylase and starch solution in 2) Test tube rack: This will be used to place the test tubes into 3) Graduated pipettes (2): These will be used to measure the amount of Amylase/starch solution needed.
Chromatography has been developed over the past century and has an important contribution in many areas of modern science. However the main original work of M.S.Tswett was published in a book Chromatographic Adsorption Analysis.
The material and equipment used was a sample of candy such as M&M’s, skittles, and Reese’s pieces. Set food colors for comparison. Filter paper or coffee filters. 0.1% salt solution {1/8 tsp salt in 3 cups of water}. Clear plastic 9 oz cups. Blow dryer. Also you will need some toothpicks and small {1 oz} plastic cups. This are the materials and equipment we used for this experiment .the objective of the experiment is to use the technique of paper chromatography to show that it can be used to separate from each other in a mixture. To understand the principles of paper chromatography.
the resulting amino acid would be sodium glycinate (see fig. 3), an example of a
As explained by Saferstein “Chromatography is a means of separating and tentatively identifying the components of a mixtur... ... middle of paper ... ... ively place the suspect or perpetrator behind bars. Analyzing soil compounds can be measured by the levels of organic molecules including n-alkanes, fatty alcohols and fatty acids, which are all found in the waxy outer layer of plant matter (Geddes, 2008). It basically states that compounds can remain in the soil for thousands of years, which explains that each area being tested has its unique organic profile.
The choice of mobile phase depends on the chemical nature of the compound of interest and could be purely organic, inorganic or a mixture of both in gradient. Most commonly used mobile phases are organic solvents like acetonitrile or methanol. Some HPLC analysis require the use of water free solvents as mobile phase and in such cases acids like formic acid, phosphoric acid, trifluoroacetic or salts which will assist in separation of components in the sample are used.
0.498 • Plate II o Solution 5: Beverage A Rf: 0.519 o Solution 6: Beverage B Rf: 0.535 o Solution 7: Beverage C Rf: 0.3 Permanganate Test Substance Tested Observations Rxn? Fresh Aqueous Aspartame Stayed purple No Solution 4 Brown w/ precipitate Yes Solution 6 Brown w/ precipitate
... point, the complete and full separation of the components, as those seen in the first part of the experiment, did not happen. This source of determinate error decreased the Rf values. Furthermore, upon placing my TLC plate into the solution I stumbled and threw the TLC plate in the jar. The solution splashed up on the TLC plate, rushing solution to move up and absorb on the TLC plate without capillary action. Because not all the solution that splashed up was not absorbed, it may have either dragged down some of the ink components or allowed for faster capillary action. This source of indeterminate error skewed the result of the Rf values, either increasing or decreasing the distance traveled of the ink. I don’t believe that this was a great source of error because the components of the unknown ink and the pen #3 still rose to similar values with similar separation.