Benzocaine Lab Report

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

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

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

In this experiment, the purpose was to determine the effect of the nicotine alkaloid in tobacco on the heart rate of Daphnia. To make certain that the effect of only one variable was being measured in this experiment, a control group was used as a reliable baseline comparison for the experimental group. It was found that the control group had an average heart rate difference of 30.67 beats per minute as shown in Table A. A difference this large in the control group was unexpected, because it was believed that the heart rate may stay fairly constant for no stimulant was added. However, this unanticipated difference may have resulted from the human handling and the heat from the microscope light.

The structure and molecular weight and formula for benzoic acid are as seen in Figure 1. This chemical is used as a preservative, and is deemed safe for consumption under specific levels.5

Dispense .5 mL water into the already weighed conical vial, replace cap and face insert on its down side.

Sodium benzoate was found in the aqueous layer and methylene chloride was added to separate the immiscible layers. Once separated, and all the organic and soluble layers were combined separately, the crude samples were heated. After crystals were formed, they were weighed to find our actual yield. Acetanilide had a percent yield of 74% and Benzoic acid had a percent yield of 54%, Table 1. The results showed that there was a higher percentage of Acetanilide

Since the neutralization reaction yields H2CO3, it's decomposition would produce carbon dioxide gas, which would bubble out of the solution. The neutralized solution was placed back into the funnel and the aqueous layer drained; after this washes with 10 mL of concentrated brine and 10 mL distilled water were performed to remove the NaCl and water produced during the neutralization out of the organic layer containing 2-chloro-2-methylbutane. The latter was then dried with anhydrous sodium sulfate, after which the percent yield of the liquid product was

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

In this experiment, the pKa, dissociation constant, of 2-naphthol was determined by measuring the UV-visible absorption spectra of solution of the acid at different pH values.

From the above data the decomposition of benzoyl peroxide was slower at lower temperatures for both the C=O and RO=OR groups. Though as the temperature was increased the amount of decomposition also increased resulting in smaller amounts of C =O and RO= OR being detected though the use of an IR. While an larger amount of these two groups were detected for the temperatures around 101C and 113C in comparison to the control which was taken.

Abstract Bromobenzene was reacted with Magnesium and anhydrous ether to create a Grignard reagent. Benzophenone was added to the reagent in order to produce triphenylmethanol. The final product’s melting point was measured at 40.5-44°C; too low to be triphenylmethanol. The final product was determined to be benzophenone, indicating that no reaction occurred. Grignard reagents were likely deactivated by water, causing the reaction to not occur.

In this experiment, methyl benzoate was synthesized from benzoic acid and methanol with acid catalyze using Fisher Esterification. First benzoic acid and methanol were mixed in 100 mL round bottom flask. We cooled the mixture in ice and poured 3 mL of conc. H2SO4 and swirled to mix compounds. Then we refluxed the mixture for 1 hour. We let the solution cool and then decanted into a separatory funnel containing 50 mL of water and rinsed the round bottom flask with 35 mL of tert-butyl methyl ether and added that to a separatory funnel. We shook and vented thoroughly and drained the aqueous layer which contained a bulk of methanol and H2SO4. We washed the solution in the separatory funnel with 25 mL of water, followed by 25 mL of sat. sodium bicarbonate

What was your null hypothesis? – As the concentration of benzoquinone increases the absorption will show no change.

Samples of benzophenone, malonic acid, and biphenyl were each tested with water, methyl alcohol, and hexane. Benzophenone was insoluble in water as it is nonpolar while water is highly polar. Benzophenone was soluble in methyl alcohol, dissolving in 15 seconds, because methyl alcohol is intermediately polar as benzophenone is nonpolar. Methyl alcohol is polar but not as much as water. Thus, the nonpolar benzophenone was soluble in methyl alcohol. Benzophenone was partially soluble in hexane because hexane is nonpolar as is benzophenone. Thus, benzophenone was dissolved in hexane. Malonic acid was soluble in water because both malonic acid and water are polar. It took 25 seconds for malonic acid to dissolve in water. Malonic acid was soluble in methyl alcohol because malonic acid is polar and methyl alcohol is intermediately polar, allowing malonic acid to dissolve in the methanol in 15 seconds. Malonic acid was insoluble in hexane because hexane is nonpolar while malonic acid is polar. Biphenyl was insoluble in water as water is highly polar whilst biphenyl is nonpolar. Biphenyl was partially soluble in methanol which is intermediately polar whilst biphenyl is nonpolar, allowing it to dissolve a little. Biphenyl was soluble in hexane because both biphenyl and hexane are nonpolar molecules. Biphenyl dissolved in hexane in 10 seconds.