The purpose and goal of this experiment is to separate a mixture of fluorene and 9-fluorenone through the method of column chromatography, and then determine the purity of the isolated compounds through thin-layer chromatography (TLC), as well as melting point analysis. Through column chromatography, gravity is utilized to move the solvent and compounds down the column, where the changes in the solvent polarity assists in eluting the desired compounds to separate fractions. Each fraction solvents can then be evaporated to obtain the compounds of interest. Through TLC, a thin layer of polar and hydrophilic silica gel on an inert sheet is used to spot the sample on the bottom of the sheet and is then developed in a jar of eluent, where through …show more content…
A small piece of cotton is then put into the bottom of the column, along with a 0.5 cm thick layer of sand (put on top of the cotton). 20 mL of petroleum ether, and with a dry funnel on top of the column, 7 g of alumina (Aluminum Oxide) is put into the column. To ensure that no alumina adheres to the sides, a glass rod in a rubber stopper can be put to use through the gentle tapping of the column with it; in addition, additional petroleum ether can also be put to use by rinsing the inner walls of the column with it. To cover the alumina, another 0.5-1 cm layer of sand is put to use. For the solvent to drain into an Erlenmeyer flask, the stopcock is to be open until the solvent level exactly reaches the top of the alumina, where the stopcock is then immediately shut off in order to prevent air bubbles from developing in the solid support. To load the sample into the column bed, 0.5 mL of a pre-made solution, containing 200 mg of fluorine and 9-fluorenone, as well as 0.5 mL of petroleum ether is to be carefully put on top of the column bed with a Pasteur pipet. At this point, the stopcock is to be open again until the top of the liquid level is at the top of the alumina. Next, with 1 mL of petroleum ether, the addition and draining process is then done a total of three more times, where upon the third draining, 10 mL of petroleum ether is be put into to the top of the column bed and put to drain into a small beaker (label it “Fraction 1”). After every 2-3 mL, a watchglass is used to collect a drop of eluent to determine if all white solid has been eluted (there may be a need of 10-20 mL of petroleum ether). Once all eluted, another small beaker (label it “Fraction 2”) can replace the beaker for “Fraction 1.” In “Fraction 2,” 5 mL of petroleum ether is used to elute (stop when yellow band starts to elute), followed by a change of eluent to dichloromethane.
The unknown bacterium that was handed out by the professor labeled “E19” was an irregular and raised shaped bacteria with a smooth texture and it had a white creamy color. The slant growth pattern was filiform and there was a turbid growth in the broth. After all the tests were complete and the results were compared the unknown bacterium was defined as Shigella sonnei. The results that narrowed it down the most were the gram stain, the lactose fermentation test, the citrate utilization test and the indole test. The results for each of the tests performed are listed in Table 1.1 below.
Once the mixture had been completely dissolved, the solution was transferred to a separatory funnel. The solution was then extracted twice using 5.0 mL of 1 M
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.
Biology Lab Report Lab No. 18: Biochemical Genetics: Smooth Peas Wrinkled Peas Data Presentation: The diagram of cotyledon for smooth and wrinkled pea is attached to the next page. The table of starch presents is below: Type of Pea Starch Present? (Color change) Smooth
In this experiment, column chromatography and thin layer chromatography were used to separate a mixture of fluorene and 9-fluorenone. These two methods were then compared, and the results were analyzed. In column chromatography, 0.1010 g of mixture was separated. During the separation, fluorene eluted first. This compound was white in color once dried with the rotary evaporator. A percent yield of 93.47% was calculated for fluorene. The product that eluted first was confirmed to be fluorene by the IR spectrum obtained and the experimental melting point. The IR spectrum RM-02-CC1 was the spectrum obtained for this compound. Aromatic carbon- hydrogen bonds, carbon-carbon double bonds and hydrogens attached to sp2 carbons were shown by peaks 3038
In this experiment, an acid-base extraction was done to separate a mixture of an unknown acid and fluorene, a neutral compound. The possible unknown acids were 2-chlorobenzoic acid, 3-chlorobenzoic acid, and 3-methylbenzoic acid. The purification of the isolated unknown acid was performed by recrystallization and its identity was established by analyzing the melting point range of the pure product and comparing it to the provided standards. In addition, a mixed melting point experimentation enhanced the fidelity of the unknown's identity when approximately equal amounts of the unknown and one of the standards (at a time) were mixed and the melting point range was recorded.
H2O + NaHCO3 (5ml of 3M and 5ml H2O) to a separatory funnel, shake mixture, allow layers to separate and draw off lower layer into a 25ml Erlenmeyer flask 2. Add additional 5ml of water to funnel, shake as before. Add 15 ml NaCl to the funnel. Shake Bottom layer is white and NaCl was added to the mixture and allowed layers to separate.
As a result, the laboratory experiment was determined to be successful and the two product samples obtained and completed calculations displayed that overall bromide was a stronger nucleophile as the chloride ion was more electronegative than bromide, which allowed it to hold electrons in closerE. In conclusion, since bromide is less electronegative and has more electrons, it was able to share the unpaired electrons more easily than chlorideA. These results were expected, as the alkyl bromide would be the major product of procedure A as it followed the SN2 mechanism which was based on nucleophile strength and the product from procedure B would be a near-equal mixture as it followed the SN1 reaction mechanismC. The methods used during this experiment allowed for a successful completion and determination of the better nucleophile, but other additions and observations would have been interesting and beneficial as well. A possible examination of the two sample products collected using pH tested values or observation of sample spotted chromatography paper under a
Using the scopula, take a small amount of the substance and add it to the spot plate. Add deionized water to the section with the substance. Stir to see if the substance dissolves or not. Record your observations.
Abstract: Using Ion Exchange Chromatography, cellulase was purified. After purification, it was analyzed using a DNS test. The purified protein did not respond to the DNS the way it was expected to.
Begin collecting samples with the pure hexane. Keep adding hexane so that the silica gel column does not run dry. Collect one 20 ml sample. Repeat with 90:10 hexane and collect 4 20-mL bottles. Repeat with 80:20 hexane and collect 2 20-mL samples.
Create wells: put a comb template in the middle of the tray; wait until the mixture becomes solid. After, remove the comb standing straight. 4. Remove rubber ends: transfer the gel tray into the horizontal electrophoresis and fill it with the concentrated electrophoresis buffer. 5. Materials and methods: Experiment: 1st, prepared milk samples should be already done by the teacher.
To the first Erlenmeyer flask with the ferrous salt add about 1/3 of the 0.75N sulfuric acid. Dissolve the salt by gently swirling it in the dilute acid. Add about 5mL of the Zimmerman-Reinhardt Reagent (this reagent contains phosphoric acid which complexes yellow ferrous ions into colorless compounds which do not obscure the endpoint; it also contains manganous ions which inhibit the oxidation of any chloride ions in the sample). The use of a white background underneath the flask aids in the detecting of the endpoint. Repeat with second sample.
Tank Chromatography Introduction: Chromatography is a method used to separate both organic and inorganic compounds so that they can be analysed. Scientists often use chromatography to figure out which basic constituents makes up a specific mixture. Chromatography relies on the principle of selective absorption. A botanist named M.S. Tswett in 1906 first discovered chromatography.
The sample was subjected to steam distillation as illustrated in Figure 1. A total of 50ml of distillate was collected while recording the temperature for every 5.0 ml of distillate. The distillate was transferred into a 250ml Erlenmeyer flask and 3.0 g of NaCl was added. The flask was cooled and the content was transferred into a 250-ml separatory funnel. Then 25.0ml of hexane was added and the mixture was shaken for 5 minutes with occasional venting. The aqueous layer was discarded and the organic layer was left inside. About 25.0ml of 10% NaOH was then added and the mixture was shaken as before. The aqueous layer was collected and then cooled in an ice bath. It was then acidified with enough 6.00 M HCl while the pH is being monitored with red litmus paper. Another 25.0 ml of hexane was added and the mixture was shaken as before. The hexane extract was saved and a small amount of anhydrous sodium sulfate was added. The mixture was then swirled for a couple of minutes then filtered. A small amount of the final extracted was tested separately with 1% FeCl3 and Bayer’s reagent.