Organic Compounds contain Carbon, a versatile bonding element due to its ability to form four stable bonds. They can be separated from mixtures and identified through Thin Layer Chromatography (TLC). TLC is a simple, and rapid analytical technique that provides qualitative information about a sample. It is based on the principle that different compounds will have different attractions to the stationary and mobile phases. Typically, already characterized compounds can be identified chemically. This allows scientists to determine if compounds have desirable structures, and if reaction conditions of unwanted products can be altered. However, with complex compounds that were never characterized, this process is insufficient. Instead, IR Spectroscopy is used. It measures the vibrations of bonds, producing a spectrum of the different energies absorbed by the molecule. By comparing the energies with standard correlation values, the identity of an unknown compound can be determined. In this experiment, the identity of an unknown organic compound will be determined using these methods. Procedure: …show more content…
The solution was placed into a separation funnel, in which the top and bottom layers were slowly filtered out into two different beakers. The bottom layer solution was heated until the ethyl acetate evaporated and only the organic compound remained. Next, a TLC technique was prepared employing silica gel as the stationary phase and 1:1 ethyl acetate hexane as the mobile phase. In order to develop a standard, a TLC plate was spotted with benzoic acid (BA), benzophenone (BZ), biphenyl (BI), and a mixture off the three. After incubating the plate in the chamber with the mobile phase, it was analyzed under a UV light. Then, the Rf values for the known compounds were calculated using the Retention Factor
2. The TLC results showed two different spots that traveled different distances on the TLC plate, one for ethyl vanillin and one for ethyl vanillin alcohol which proves there is no evidence of the starting material in our final product. The product (ethyl vanillin alcohol) was more polar and interacted more with the solvent than our starting material (ethyl vanillin). This increase in polarity is due to the extra alcohol group in the ethyl vanillin alcohol and the smaller Rf value also indicates it is more polar and pure than the ethyl vanillin.
There are millions of different organic compounds. Most of them are found in mixtures and in order to achieve a pure form they need to be separated, isolated, and purified. However, there are endless numbers of possible mixtures, which make it impossible to have a pre-designed procedure for every mixture. So chemists often have to make their own procedures. The purpose of this experiment was to prepare the student to the real world by them designing their own procedure which will help them understand the techniques of separation and purification better. The goal was to extract two of the components of the
0.300 grams of biphenyl/ p-toluidine sample was weighed. Next, 10 mL of dichloromethane was measured in a graduated cylinder. The dichloromethane was transferred to a small beaker then the solid mixture was dissolved in it. A Thin Layer Chromatography (TLC) was conducted with the dissolved mixture in 20% Ethyl Acetate and 80% Hexane solution. The TLC plate was observed to be impure with two spots. To being extraction, a separatory funnel was placed inside of the hood and the stopcock was closed. A flask was placed under the funnel then the mixture was added to the funnel. Next, 10 mL of 3M HCL was measured in a graduated cylinder and
Identifying the three components of the unknown mixture, a 1.5 g sample was obtained and dissolved in 30 mL of diethyl ether. This solution was then poured into a separatory funnel with a funnel with the stopcock closed, and inverted twice so that there would be a formation of different layers in the mixture. In order to extract the base from the mixture, approximately 14 mL of 10% hydrochloric acid was added into the funnel and mixed. To mix the hydrochloric acid thoroughly the funnel was gently shaken with the pressure released by removing the stopper intermittently. The solution then separated into an aqueous layer at the bottom, and an organic layer at the top (containing the acid).1 The aqueous layer (containing the base) was released into an
During this investigation the question we looked to answer was: what are the identities of the unknown compounds? In an effort to answer the question, our group designed a method in which the relationships between the unknown compounds in plastic bags were compared so that their identities could be determined. The mole (mol) provides a measure of the number of atoms present in the sample of a compound. One mole of an element or compound contains
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.
Introduction: The fundamental techniques of organic chemistry lab, commonly known as SIPCAn, include separation, isolation, purification, characterization, and analysis (1). Through SIPCAn, students learn the fundamental techniques of organic chemistry laboratory. Mastering these techniques are necessary in order to perform more complicated experiments and to carry out organic reactions and synthesis. The information gained from SIPCAn included boiling point, melting point, and density can be used to identify unknown compounds. Simple distillation was used to purify a compound by separating it from a
Benzophenone (1.00g, 0.0054 mole) was measured and added into a 100 mL round-bottom flask. Next, 95% of EtOH (15 mL) was measured and placed in the round-bottom flask and a stir bar was added. The mixture was heated on a sand bath until the benzophenone dissolved completely. The round-bottom flask was removed from the sand bath and it cooled for a few minutes. A preliminary TLC was conducted with 20% ethyl acetate and 80% hexanes solution.
After the unknown tablet’s identity has been discovered and all the UV analyses are compared, an iodine analysis can be done. The plates were placed in a jar containing a few iodine crystals and sealed off with a cap before warming it gently on a warm hot plate until the spots begin to appear. A few spots become visible, as well as their distinct relative colors, which allows for direct comparison between the colors of the reference spots to those on the unknown plate(s). The plates were removed from the jar, observations were recorded into the lab notebook, and the experiment is now
Different reagents were used for the tests with the reagents reacting with the molecules in a specific way indicated by a change of color. Controls were provided to ensure integrity of the process. The results indicated the presence or absence of the organic molecules in the various substances provided. They proved that using these tests, one can accurately determine what organic molecules a substance contains. This will help in determining the composition of various substances within the cell or even outside the body and how they affect normal cell
Part 2 to determine the empirical formula and percentage yield of the compound synthesized in Part 1. Spectrophotometry is a routine laboratory test that has the added advantage
Samples A, B, and U were prepared by depositing 1-3mg of the solid- compound A, B, and the unknown- in a test-tube; dissolved with acetone. A TLC plate was made by drawing a horizontal line at the top and bottom of the plate with four ticks- A, B, U and A+U or B+U. The solutions were distributed to the ticks with a spotting capillary tube; however, based on the results from the melting point analysis, the determined unknown- compound A or B- and the unknown would be place on the fourth tick.
By Using specific methods of compounds detection, we can match an unknown compound with a known compound because similar compounds will display similar characteristics. In this experiment, identifications of the unknown ketone was accomplished using thin layer chromatography, melting point, and NMR spectrometry. Thin layer chromatography is very quick but sensitive way of determining the components of a mixture or a specific compound from a list of knowns. This method is the one which was utilized in the
The objective of this lab was to use qualitative and quantitative measurements and observations to properly identify, and then confirm the identity of an unknown compound. After identification, the compound would have to be synthesized, in our case, through an acid-base reaction, followed by confirming its identity with the original unknown compound.
Objective: The objective of this experiment is to use acid-base extraction techniques to separate a mixture of organic compounds based on acidity and/or basicity. After the three compounds are separated we will recover them into their salt forms and then purify them by recrystallization and identify them by their melting points.