In this experiment, the goal is to separate naphthalene and benzoic acid from one gram of a crude mixture containing them both, using extraction. A general requirement of a solvent in extraction is solvating one of the pure compounds in solution but not the other. Position in the separatory funnel is determined by density of each layer. The denser layer will be on the bottom of the separatory funnel while the less dense layer will be the top layer of the separatory funnel. For extraction to be used as an effective method for separation, the components of a mixture that need to be recovered must not be soluble in the same solvent. Benzoic acid is not soluble in water, but is soluble in diethyl ether. In benzoic acid, the benzene ring is nonpolar …show more content…
The aqueous layer was on the bottom because it was denser than the organic layer. The aqueous layer contained the benzoic acid and the organic layer contained the naphthalene. The drying step was partially successful in the experiment because it rid the organic layer of excess water. In the end, the melting point range of the naphthalene was 55-62 °C, unlike the actual determined melting point of 80.2 °C. There is a possibility that less than needed sodium sulfate had been added to the organic layer mixture because the melting point could have been negatively affected by excess water not absorbed by the sodium sulfate. The acidification step was successful, because it allowed the Benzoic acid to precipitate out. There was a 58% yield of benzoic acid from the crude sample, and a 98% yield of naphthalene and benzoic acid, which is great as far as results go. It means enough hydrochloric acid, HCl, was added for the conjugate acid, benzoic acid, of the base, benzoate that was in the aqueous layer Erlenmeyer flask before the addition of the acid. The separation of naphthalene and benzoic acid seemed successful as far as turnout of product came. Out of the 1.00 g of crude sample started with, 0.40 g of naphthalene was recovered and 0.58 g of benzoic acid was recovered. But as far as comparing the observed Mel-temp melting points to the actual melting points, there was a big difference between the values observed and the real melting point values. The Mel-temp temperatures for benzoic acid and naphthalene were 85-95 °C and 55-62 °C, respectively. The actual values of temperature for benzoic acid and naphthalene were122.4°C and 80.2°C, respectively. This showed that the “pure” samples were still impure in some way. It seemed as though maybe not enough vacuum filtration and drying time were causations of impure samples, probably tainted by water. The crude sample Mel-temp temperature was 55-63 °C. This
The theoretical weight was 599.6 mg. This yields a percent yield of 3.7%. Table 1 also illustrates the experimental melting point of 99.3-102.1◦C. A melting point that has a range larger than 3◦C is indicative of impurities in the sample. A few possibilities of impurities could have been unreacted norbornene, and water. Evidence that supports that there was unreacted norbornene in the final sample was the fact that the product was a jelly-like structure. Norbornene by itself has a jelly-like structure. However, once norbornene reacted with the acid-catalyst (H2O2), then it should have changed the chemical structure of the molecule and once the solution was brought back down to room temperature, crystals should have formed. Since a jelly-like, or oil-like product was present at the end of the reaction, then this is indicative that there was unreacted norbornene in the sample. The second impurity that may have been present in the final product was water. Instead of adding 3 mL of sodium bicarbonate and then 3 mL of brine, 3 mL of brine was added first and then 3 mL of sodium bicarbonate was added. This experimental error caused excess aqueous solution to be added to the diethyl ether. Since excess water was added to the final product, about 4x the amount of anhydrous sodium sulfate was needed in order to remove the water from the product. This was another indication that there was too much water in
Firstly, an amount of 40.90 g of NaCl was weighed using electronic balance (Adventurer™, Ohaus) and later was placed in a 500 ml beaker. Then, 6.05 g of Tris base, followed by 10.00 g of CTAB and 3.70 g of EDTA were added into the beaker. After that, 400 ml of sterilized distilled water, sdH2O was poured into the beaker to dissolve the substances. Then, the solution was stirred using the magnetic stirrer until the solution become crystal clear for about 3 hours on a hotplate stirrer (Lab Tech® LMS-1003). After the solution become clear, it was cool down to room temperature. Later, the solution was poured into 500 ml sterilized bottle. The bottle then was fully wrapped with aluminium foil to avoid from light. Next, 1 mL of 2-mercaptoethanol-β-mercapto was added into fully covered bottle. Lastly, the volume of the solution in the bottle was added with sdH2O until it reaches 500 ml. The bottle was labelled accordingly and was stored on chemical working bench.
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.
The purpose of the experiment was to use the method of simple distillation to separate hexane, heptane, and a mixture of the two compounds into three different samples. After separation, gas chromatography determined the proportions of the two volatile compounds in a given sample.
There were many things that I learned in Module 7 . Some of them where: what is the difference between an acid and a base; what is pH; what is equilibrium, what is Le Châtelier’s principle; and what is oxidation. Here are some of the things that I learned in lesson 07.01 (Acids and Bases) and lesson 07.02 (Acid-Base Reactions).
Ensure gloves are worn at all times when handling strong acids and bases within the experiment of the preparation of benzocaine. 4-aminobenzoic acid (3.0g, 0.022 moles) was suspended into a dry round-bottomed flask (100cm3) followed by methylated sprits (20 cm3). Taking extra care the concentrated sulphuric acid of (3.0 cm3, 0.031 moles) was added. Immediately after the condenser was fitted on, and the components in the flask were swirled gently to mix components. It should be ensured that the reactants of the concentrated sulphuric acid and the 4-aminobenzoic acid were not clustered in the ground glass joint between the condenser itself and the flask. In order to heat the mixture to a boiling point, a heating mantle was used and then further left for gently refluxing for a constituent time of forty minutes. After the duration of the consistent forty minutes the rou...
The hypothesis that was formed in this experiment was that decantation and distillation were the techniques that would be successful in separating the three layered substances. The oil on top of the mixture was to be decanted solely, and the salt and sand layers would be distilled and separated together on filter paper on top of boiling hot water. The reason that the oil is decanted is because it doesn’t mingle with the salt and sand layers, and in addition it was the top layer, which was thought to have been easy to separate first. And as for the sand and salt, sand doesn’t mix and dissolve in water compared to salt, which does in fact dissolve, so distillation was thought to be the proper solution to separating the two
Then the reaction tube was capped but not tightly. The tube then was placed in a sand bath reflux to heat it until a brown color was formed. Then the tube was taken out of the sand bath and allowed to cool to room temperature. Then the tube was shaken until a formation of a white solid at the bottom of the tube. After formation of the white solid, diphenyl ether (2 mL) was added to the solution and heated until the white solid was completely dissolved in the solution. After heating, the tube was cooled to room temperature. Then toluene (2 mL) was added to the solution. The tube was then placed in an ice bath. Then the solution was filtered via vacuum filtration, and there was a formation of a white solid. Then the product was dried and weighed. The Final product was hexaphenylbenzene (0.094 g, 0.176 mmol,
The purpose of this experiment was to learn and preform an acid-base extraction technique to separate organic compounds successfully and obtaining amounts of each component in the mixture. In this experiment, the separation will be done by separatory funnel preforming on two liquids that are immiscible from two layers when added together. The individual components of Phensuprin (Acetylsalicylic acid, Acetanilide, and Sucrose as a filler) was separated based upon their solubility and reactivity, and the amount of each component in the mixture was obtained. Also, the purity of each component will be determined by the melting point of the component.
For this experiment we have to use physical methods to separate the reaction mixture from the liquid. The physical methods that were used are filtration and evaporation. Filtration is the separation of a solid from a liquid by passing the liquid through a porous material, such as filter paper. Evaporation is when you place the residue and the damp filter paper into a drying oven to draw moisture from it by heating it and leaving only the dry solid portion behind (Lab Guide pg. 33.).
In order to separate the mixture of fluorene, o-toluic acid, and 1, 4-dibromobenzene, the previously learned techniques of extraction and crystallization are needed to perform the experiment. First, 10.0 mL of diethyl ether would be added to the mixture in a centrifuge tube (1) and shaken until the mixture completely dissolved (2). Diethyl ether is the best solvent for dissolving the mixture, because though it is a polar molecule, its ethyl groups make it a nonpolar solvent. The compounds, fluorene and 1, 4-dibromobenzene, are also nonpolar; therefore, it would be easier for it to be dissolved in this organic solvent.
Preparing Benzoic Acid from Benzylalcohol Planning (a) Problem The aim of this experiment is to synthesize benzioc acid, with the highest possible yield, by oxidizing benzylalcohol. Hypothesis We expect the percentage yield to be about 50% due to several processes such as cooling and filtering. Possible Variables - Time - Temperature (of water) - Filter Planning (b) Apparatus/ Materials - Round bottomed flask under reflux - benzylalcohol - HCl - Na2O4 - Büchner funnel - beakers - sodium carbonate Procedure The benzioc acid is synthesized by heating benzylalcohol in a round bottomed flask under reflux. In addition to that, we use Na2O4 as a oxidizing agent. After that, we use HCl to precipitate it.
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.
When benzoic acid paired with 1.0 M NaOH, it was observed that both compounds were soluble. Upon the addition of 6.0 M HCl into this solution, benzoic acid became insoluble. Benzoic acid was also insoluble in 1.0 M HCl. Ethyl 4-aminobenzoate was found to be insoluble in 1.0 M NaOH and soluble in 1.0 M HCl. But then, after adding 6.0 M NaOH into the test tube C (mixture of ethyl 4-aminobenzoate and 1.0 M HCl), a white powdery solid (undissolved compound) was formed. These demonstrate that both the acid and base became more soluble when they were ionized and less soluble when they were
Preparation of Ethanol and Ethanoic Acid Introduction to report ---------------------- This report contains 5 practical experiments to produce ethanoic acid from ethanol. The first practical is the preparation of ethanol from glucose using yeast during the process of fermentation; this has been demonstrated in class. In this practical the glucose is converted into ethanol and carbon dioxide by respiratory enzymes from the yeast. The ethanol solution will be between 5-15% and the ethanol will be separated from the yeast by filtering.