Results:
Limiting Reactant: Eq 1 Limiting reactant = Benzoin
Theoretical yield of Benzil:
Eq 2
Theoretical Yield Benzil | 0.296 g | Mass of Crude Benzil | 0.188 g | Mass of Final Benzil | 0.127 g | % Yield | 43% | % Recovery | 66% |
Table 1: Mass of crude/final Benzil, % yield, and % recovery
Percent Yield: % Yield = (Final product/Theoretical product) x 100 Eq 3 = (0.127 g/0.296 g) x 100 = 43% yield
Percent Recovery % Recovery = (Final product/Crude product) x 100 Eq 4 = (0.127 g/0.188 g) x 100 = 66% recovery
Theoretical Yield Benzilic Acid:
Eq 5
Theoretical Yield Benzilic Acid | 0.109 g | Final Benzilic Acid | 0.060g |
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The percent yield, calculated using the theoretical and final amount of benzil, was 43% (see Eq 3). The percent recovery, calculated using the crude and final amount of benzil, was 66% (Eq 4). The melting points of crude and final benzil were 82.5 – 85.6C and 94.2C respectively (Table 3). The literature value for pure benzil is 95C and the final crystallized benzil temperature value is very close to the literature value. This testifies the purity of the experimental benzil. The melting point value of the crude was much lower and the range was much wider due to the impurities. For further conformation of the purity of experimental benzil, the infrared spectroscopy was observed. . The following functional groups were determined on the infrared spectroscopy according to their corresponding wavenumbers: aromatic, sp2 C-H bonds, and C=O/carbonyl group (Table 4). Benzil incorporates all of the above functional groups. The melting and infrared spectroscopy confirmed that the final product created was Benzil.
In the following reaction, benzil was rearranged to from benzilic acid by reacting it with potassium hydroxide in ethanol. 0.100 benzil was utilized and the theoretical yield of benzilic acid was 0.109 grams (see Eq 5). The final yield and weight of benzilic acid was 0.60 grams. The final yield and theoretical yield were used to calculate the percent yield, 55% (similar to Eq 3). The melting point of benzilic acid was 148.3C and the literature value for
Throughout today’s society, media contributes to almost everyone’s daily life. From informative news channels to comical television shows, media proves to be effective in advertisement, releasing messages and informing the audience. Although media proves to be wildly effective in advertising, releasing messages and informing the audience, periodically destructive and misleading messages are provided to the audience and directly influencing women. Cultural critics widely agree that media tends to negatively influence women and all the critics point to research which supports the belief that women are portrayed as subordinate to men, having no
The original 1.0 gram of the 50/50 mixture of the benzoic acid and benzil contain 0.5 gram of benzil. Thus, from 0.5 gram of benzil, only 0.266 gram of benzil was collected. The percent recovery of benzil was calculated to be 53.2%. This low percent recovery could be due to filtration errors. Some amount of benzil remained on the filtration paper that contained the MgSO4. In order for determining the purity of the
The purpose of this experiment was to synthesize the Grignard reagent, phenyl magnesium bromide, and then use the manufactured Grignard reagent to synthesize the alcohol, triphenylmethanol, by reacting with benzophenone and protonation by H3O+. The triphenylmethanol was purified by recrystallization. The melting point, Infrared Spectroscopy, 13C NMR, and 1H NMR were used to characterize and confirm the recrystallized substance was triphenylmethanol.
The hydrobenzoin (meso) product of the benzil was isolated through the techniques of recrystallization and vacuum filtration. Because there NaBH4 was the limiting reagent in the experiment, 0.005604moles of NaBH4 should yield 1.2008g of hydrobenzoin (meso). The mass of the isolated product was 0.613g, resulting in a 51.1% yield. There are many reasons to account for the loss of 48.9% of
In this lab, liquid-liquid extraction was performed to isolate a mixture of benzocaine and benzoic acid. 2.0107 grams of the mixture was first weighed out for the trials. When HCl was added to the mixture for the first acid extraction of benzocaine, an emulsion formed during inversion and venting that prevented a defined separation of the two layers. 8 mL of water was therefore added before continuing the extraction. The addition of NaOH then turned the top aqueous layer basic, indicated by the pH strips that turned blue when tested. A vacuum filtration isolated 0.29 grams of benzocaine and a MelTemp apparatus measured the crystal’s melting point ranges to be 85.1C-87.4C. For the base extraction of benzoic acid, the aqueous layers were retrieved
It has recently been brought to my attention that our school is looking to adopt a sustainable menu into our meal program and I would like to give my viewpoint on the matter. As one many students here at Oxford Academy this change will affect me directly. Although people may at first oppose this conversion I think if we are able to overcome the first obstacles, this change would bring a great positive impact to the environment and the health of our students.
Abstract: One mixture of two unknown liquid compounds and one mixture of two unknown solid compounds were separated, isolated, purified, and characterized by boiling point. Two liquid unknowns were separated, isolated, and purified via simple distillation. Then, the process of an acid-base extraction and washing were used to separate two unknown compounds into two crude compounds: an organic acid and a neutral organic compound. Each crude compound was purified by recrystallization, resulting in a carboxylic acid (RCO2H) and a pure organic compound (RZ). The resulting mass of the pure carboxylic acid was 1.688g with a percent recovery of 31.80%, the boiling range was 244-245 °C, and its density was 2.0879g/mL. The resulting mass of the pure organic solid was 2.4902g with a percent recovery of 46.91%, the boiling range was 52.0-53.4°C, and its density was 1.5956 g/mL.
Objective: In steam distillation lab (lab 3), we must obtain pure Eugenol from cloves through the process of steam distillation. In the crystallization lab (lab 4) part 1, we must acquire the best possible pure crystallization of acetylsalicylic acid from aspirin and in part 2 we must obtain a similar pure crystallization of benzil from an impure mixture of benzil.
The product obtained had a melting point of approximately 107 °C and a weight of .324 grams. Some of the product would not dissolve in water and so was removed through vacuum filtration, which left .141 g not dissolved in solution. It took 13.2 mL of sodium hydroxide to turn the solution of the product dissolved in water pink. A molecular weight of 138.63 g/mol was calculated from the data. These results indicate that the product was 2-methylbenzoic acid, the Grignard reagent was 2-methylphenylmagnesium bromide, and the unknown bromide solution was 2-methylbromobenzene. Calculations showed that the limiting reagent of the Grignard preparation was magnesium and that the experiment had a 23.13 % yield.
In order to isolate benzoic acid, benzocaine and 9-fluorenone, each component needed to be separated from one another. All three compounds began together in one culture tube, dissolved in methylene chloride and formed into a homogenous mixture. In this culture tube, two milliliters of aqueous three molar hydrochloric acid was added, which immediately formed two layers, the top acidic aqueous layer was clear in color and contained benzocaine, and the bottom organic formed was yellow and contained benzoic acid and 9-fluorenone. Benzocaine’s amino group is protonated by the aqueous layer hydronium. This protonation forms the conjugate acid of benzocaine, benzocaine hydrochloride. Thus, the conjugate acid, benzocaine hydrochloride is a salt in which is soluble in water and furthermore can be isolated from the organic mixture. When testing out the pH levels in benzocaine, the pH test strip was dark blue in color, indicating a pH level of around 5 to 7. When isolating benzoic acid, two milliliters of aqueous three molar sodium hydroxide was added, which deprotonates the carboxylic group in benzoic acid, forming its conjugate base, sodium benzoate. As with benzocaine hydrochloride, sodium benzoate is a water soluble ionic salt in the aqueous layer that can then be separated from the bottom organic layer containing the 9-fluorenone. The pH test strip was a vibrant red for benzoic acid, indicating a pH of 2. Now the 9-fluorenone is left, deionized water is added to remove any excess
After 10 minutes the reaction liquid was separated from the solid using a vacuum filtration system and toluene. The product was stored and dried until week 2 of the experiment. The product was weighed to be 0.31 g. Percent yield was calculated to be 38.75%. IR spectra data was conducted for the two starting materials and of the product. Melting point determination was performed on the product and proton NMR spectrum was given. The IR spectrum revealed peaks at 1720 cm-1, which indicated the presence of a lactone group, and 1730 cm-1, representing a functional group of a carboxylic acid (C=O), and 3300cm-1, indicating the presence of an alcohol group (O-H). All three peaks correspond with the desired product. A second TLC using the same mobile and stationary phase as the first was performed and revealed Rf Values of 0.17 and 0.43for the product. The first value was unique to the product indicating that the Diels-Alder reaction was successful. The other Rf value of 0.43 matched that of maleic anhydride indicating some
Experiment 4A: Determination of a Partition Coefficient for Benzoic Acid in Methylene Chloride and Water, and Experiment 4B: Solvent Extraction I: Acid-Base Extraction Using the System Benzoic Acid, Methylene Chloride, and Sodium Bicarbonate Solution
Technological advances and the development of social networking sites should be a reason for us to reconsider the existence of the United States Postal Services. Honestly, who would use inconvenient and slow mail, when they can electronically communicate with the whole world at the press of a button? I don’t find any use in preserving the US Postal service – there is no need to waste time and effort in changing, reorganizing, and revitalize an ineffective business to meet the needs of the changing world!
The purpose of this lab was to synthesize triphenylmethanol from benzophenone and bromobenzene by the formation of a Grignard compound with the reagents bromobenzene and magnesium metal. The bromobenzene was first transformed into the Grignard compound and was then reacted with the benzophenone to make the final product. The mixture was then mixed with sulfuric acid and the organic layer was extracted via a separatory funnel. The mixture was then recrystallized from methanol and was allowed to dry and the percent yield, melting point, and the IR was obtained. The mass of the product obtained was 5.45 grams and the percentage yield was determined to be 41.95%. The melting point range obtained from the final product was 89-91°C
Before the start of the experiment, the theoretical yield was to be calculated. First, the limiting reagent was determined from the reagents by comparing the amount of moles. Among the three reagents involved in this experiment - camphor, sodium borohydride, and methanol, camphor was found to be the limiting reagent. The moles of camphor was less than the combined moles of the other two reagents. The theoretical yield, which is the amount of product that could be possibly produced after the completion of a reaction (“Calculating Theoretical and Percent Yield”), was found to be 0.25 g. Once the product was achieved, a percent yield of 97% was determined. As a result, the reduction of camphor to isoborneol was successful.