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Essay for column chromatography
Using column chromatography to separate fluorene and 9-fluorenone
Quiz on column chromatography
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In this experiment, Column Chromatography was used to separate and purified a mixed sample of Fluorine and Fluorenol. This was done by relying on this differences in polarity. Because of OH group present in the Fluorenol, that makes this substance much more polar, which cause it to move down the column at a much slower rate. After the procedures were done, the solution was collected into 13, 3 mL vials. By using TLC, the different compounds were separated and combined. Fractions #1-3 contained Flourine, #4-10 contained Fluorenol, and #11-13 did not show any significant signs of either compound. The lower determined Rf values for Fluorenol indicated that it was a more polar substance that Fluorine. Out of the beginning amount of 0.0680 grams
Fluorescence measurement provides very important information about the photochemistry of a particular molecule. The first part of this experiment was dealing with the fluorescence behavior of a Leucophor PAF. Information from both spectrophotometry and fluorimetry was used to measure the quantum yield as well as to explain why Leucophor PAF was use as commercial optical brightener. The second part of this experiment dealing with fluorescence quenching of quinine bisulphate solution (QBS) is the presence of sodium chloride.
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
Compounds resulting from heterocyclic chemistry form a huge family of variations of organic compounds with cyclic or acyclic structures having carbons and at least another element with the most common being sulfur, oxygen, fluorine or nitrogen 49. Such heterocyclic compounds must have their rings having heteroatoms and the rings could be unsaturated or saturated as well 1. These compounds are usually classified as aromatic or alicyclic heterocycles 6. The latter contain cyclic analogues of thioethers, ethers and amines 6. It has been studied before that the families of nitrogen- sulfur heterocycles have aromatic compounds that are very stable19. Also, fluorinated compound using trifluoromethyl group is often used to reduce in vivo metabolism of potential drugs, in addition to improving cellular membrane permeability (LogP)88. Sulfur and Nitrogen organic compounds heterocycles are basically drawn from aromatic heterocycles realized when a heteroatom occupies the position of a carbon atom in the ring of an organic aromatic
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
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.
The procedure for this laboratory assignment is on the following pages. 3) Separation of Carboxylic Acid, Phenol and Neutral Substance. The purpose of this acid/base extraction is to separate a mixture of equal parts of benzoic acid(strong acid) and 2-naphthanol(weak base) and 1,4- dimethoxybenzene(neutral) by extracting from tert-butylmethyl ether(very volatile).The goal of this experiment was to identify the three components in the mixture and to determine the percent recovery of each from the mixture. 4) Separation of a Neutral and Basic Substance. A mixture of equal parts of a neutral substance containing either naphthalene or benzoin and a basic substance containing either 4-chloroaniline or ethyl 4-aminobenzoate were to be separated by extraction from an ether solution. Once the separation took place, and crystallization was carried out, it became possible to determine what components were in the unknown mixture, by means of a melting point determination.
Sub-Sub-point: The main fluoride chemical that is added to water is not what most people would call a naturally occurring compound. It is a corrosive acid captured in the air pollution control devices of the phosphate fertilizer industry.
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.
The isomerization procedure was done in order to create dimethyl fumarate from dimethyl maleate. Dimethyl maleate and dimethyl fumarate are cis and trans isomers, respectively. This procedure was done via a free radical mechanism using bromine. The analysis of carvones reaction was done in order to identify the smell and optical rotation of the carvone samples that were provided. The odor was determined by smelling the compound and the optical rotation was determined using a polarimeter.
To remove the impurity, the fluorene had to be recrystallized and purified. In an aside step, 15 mL of ethanol was heated until the solvent was boiling. Ethanol is the ideal solvent to crystallize fluorene, because it is polar. Though fluorene is nonpolar, fluorene is not too soluble or insoluble in ethanol. The decision for selecting this solvent came from past experimentations as well. At first, methanol would have been a good solvent for fluorene, but methanol evaporates very quickly. A greater amount of methanol would have been required to dissolve the impure fluorene, but a little amount of ethanol is only needed to dissolve the impure fluorene completely. Once the ethanol solvent was boiling, a small amount was added to the flask, just enough to cover the impure fluorene solids. That flask was then heated on a hot plate, and additional hot ethanol was added continuously until the fluorene completely dissolved (10). As soon as the solid dissolved, the flask was stoppered and placed into an ice-water bath (11). Crystallization happened almost
In this experiment, a mixture of three substances (benzoic acid, 2-naphthol, and 1-4 dimethoxybenzene) will be separated based off acidity strength using the liquid-liquid extraction technique through a separatory funnel. Benzoic acid and 2-napthol will be converted into ionic salts when reacting with their appropriate bases (sodium bicarbonate and sodium hydroxide). Both ionic salts will then form solids through the addition of acidic HCl. Neutral 1,4 – dimethoxybenzene forms a solid through the evaporation of ether. Each compound will then be purified through recrystallization, using the processes of dissolving the solid in either water or methanol, and isolating the solid through vacuum filtration. After a week of evaporation, the compounds will then be examined for both
According to the graph on amylase activity at various enzyme concentration (graph 1), the increase of enzyme dilution results in a slower decrease of amylose percentage. Looking at the graph, the amylose percentage decreases at a fast rate with the undiluted enzyme. However, the enzyme dilution with a concentration of 1:3 decreased at a slow rate over time. Additionally, the higher the enzyme dilution, the higher the amylose percentage. For example, in the graph it can be seen that the enzyme dilution with a 1:9 concentration increased over time. However, there is a drastic increase after four minutes, but this is most likely a result of the error that was encountered during the experiment. The undiluted enzyme and the enzyme dilution had a low amylose percentage because there was high enzyme activity. Also, there was an increase in amylose percentage with the enzyme dilution with a 1: 9 concentrations because there was low enzyme activity.
LAB REPORT 1st Experiment done in class Introduction: Agarose gel electrophoresis separates molecules by their size, shape, and charge. Biomolecules such as DNA, RNA and proteins, are some examples. Buffered samples such as glycerol and glucose are loaded into a gel. An electrical current is placed across the gel.
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.
Chemistry: Acid-Base Titration. Purpose: The objective of this experiment were: a) to review the concept of simple acid-base reactions; b) to review the stoichiometric calculations involved in chemical reactions; c) to review the basic lab procedure of titration and introduce the student to the concept of a primary standard and the process of standardization; d) to review the calculations involving chemical solutions; e) to help the student improve his/her lab technique Theory: Titration was used to study acid-base neutralization reaction quantitatively. In acid-base titration experiment, a solution of accurately KHP concentration was added gradually to another solution of NaOH concentration until the chemical reaction between the two solutions was completed. The equivalence point was the point at which the acid was completely reacted with or neutralized by the base.