Caffeine And Hydrochloride Lab Report

Many manufactures release the caffeine content of their products publically, but not always, and new products and flavors are continuously introduced to the market. If quality checks are not performed, manufactures may alter the caffeine and benzoic acid content to suit the demands without public knowledge. To ensure the levels of caffeine and benzoic acid in products do not exceed the established safe limits and to inform the public of the amount of these compounds being consumed, various methods of analysis have been performed. Before the introduction of modern techniques, spectrophotometric methods alone were used to determine concentration of a compound in a mixture.6 The caffeine content in coffee, tea, soft drink, and energy drinks were determined using an immunoassay.7 The caffeine content in mixtures also used to have to be extracted before quantification.8

← I would repeat the experiment with the caffeine solution more times, so that the results I would get will be more

Caffeine is a wildly use drug in today’s society. Caffeine is a methylated xanthine which acts as a mild central nervous system stimulant (MS & RL, 2001). It is a stimulant which acts upon the central nervous system and increases alertness, wakefulness and restlessness and it increases the release of catecholamine from renal medullar (Fernandez, 2016; Collines, 2007). It is present in many beverages. Caffeine is found in coffee, tea, soft drinks, products containing chocolate (cocoa) and some medication (Collines, 2007). It is used as a cardiac and respiratory stimulant (Collines, 2007).Caffeine is the most frequently ingested pharmacologically active substance in the world (Collines, 2007).

In the first acid extraction of benzocaine, the compound was dissolved in the organic solvent of dichloromethane. When the mixture was shaken with HCl, benzocaine’s amine group gained a proton and became more soluble in water than dichloromethane. This allowed the newly formed hydrochloric salt to migrate to the aqueous layer. However, the addition of NaOH to the acidic aqueous layer regenerated benzocaine by deprotonation, making it insoluble in the aqueous layer. The precipitation of an ionic salt was therefore recovered by vacuum filtration and had a tested melting point range of 85.1C-87.4C compared to 88C-90C, the literature melting point of benzocaine. The similarity in melting point ranges, but low percent yield of 30.37% proves that the extract was somewhat successful. Lower yields may be the result of spillage performed in the lab. In the second basic extraction, the organic layer now included benzoic acid and benzamide. When treated with NaOH to deprotonate benzoic acid, the newly formed sodium benzoate transitioned to the aqueous layer as a sodium salt. Benzoic acid is regenerated once again after the addition of HCl and became insoluble in the aqueous layer after protonation. Its precipitation was then filtered out for a 65.87% recovery. Compared to its literature melting point of 122.41C, the resulting 120.9C-123.5C melting range of the sample also supports the accuracy of the separation due to its similarities and high percent yield. In conclusion, the usage of base and acid liquid extraction was mostly successful in this experiment because it was able to efficiently and properly isolate the impure mixture into two separate components of benzocaine and benzoic acid. By performing the techniques of extraction and vacuum filtration, the similarities between literature and tested

5.    Prepare the caffeine solution by dissolving 10g of caffeine tablets in 100ml of water in a beaker. Label the beaker ‘caffeine’. Similarly, add 10g of coffee to 100ml of water in another beaker and label it ‘coffee’.

These layers can be separated through the use of a seperatory funnel which drains the bottom layer into a separate container. This method uses the understanding of partition ratios of solutes to different paired solvents to produce an equilibrium leaning towards one solvent over another, thereby extracting a compound from one liquid to the other (Padias 128-37). For example, consider a mixture containing two solutes, solute A and solute B, and two immiscible solvents, solvent A and solvent B. If solute A dissolves well into solvent A, but not very well into solvent B, and solute B dissolves well into solvent B but not very well into solvent A, there would be a higher ratio of solute A in solvent A than in solvent B, and a higher ratio of solute B into solvent B than in solvent A. One can then see that, through the use of different solvents, two dissolved solutes can be separated from a mixture. This ratio of a solute concentration to different solvents is defined by K, the distribution constant. Successive filtrations yield’s a higher percentage of products.

The effects of caffeine and alcohol on daphnia are expressive of whether these substances are harmful or beneficial to the organism. By understanding the results of this experiment, it may also be understood how these substances effect humans. In this study, one daphnia was exposed to increasing levels of alcohol, while the other was exposed to increasing levels of caffeine, each in order to test the hypothesis that when given amounts of caffeine and alcohol, the daphnia will be affected the same way a human would. The effect of each substance was measured by the daphnia’s heart rate one minute after the substance was added. Results reveal that alcohol slows the heart rate, while caffeine increases heart rate. Furthermore, caffeine shows a

In this experiment, thin layer chromatography (TLC) was used to identify and compare polarity of two molecules, caffeine and acetaminophen. Chromatography is defined as the separation of a mixture of chemicals as they flow at different rates over a stationary phase based on their relative polarity. Caffeine, the more polar molecule had a greater affinity for the polar silica gel stationary phase causing it to consistently have a lower retention factor regardless of the mobile phase. This methodology can be effectively used to distinguish and analyze the polarity various of chemical mixtures such as within medicines, inks, etc.

Components containing caffeine were composed into stock solutions. These solutions were diluted to 1: 10 substance: mobile phase. A stock solution of caffeine was diluted 1:50. A sequence of diluted caffeine solutions were prepared for use as a standard (ppm): 1, 2, 4, and 10. Solutions of acetaminophen, acetylsalicylic acid, and Goody’s Powder were developed to differentiate chromatographic peaks observed. These solutions were subjected to HPLC for examination of the observed peak area and retention time for the set of compounds. Comparison of retention time allowed for the differentiation of peaks observed. The peak area obtained was utilized to determine the relative concentration of caffeine present in Goody’s Powder based on the relationship obtained in the standard. The content of caffeine present in Goody’s Powder by percent weight was identified.

The following procedures and materials were thought up by my partner and me, which was done on a small scale due to lack of time to perform a full fledge experiment that involved a large sample size. Our project consisted of a sample size of ten people in which each subject was given a survey to complete and a consent form to sign stating what the experiment was about. We also expressed with the up most confidence that their scores and identities within this research will be kept confidential. We articulated to each subject to not drink any caffeine four hours prior to the experiment so that we would not have any type of bias. My partner and I obtained ten cups (regular coffee cups) on day 1 and filled each cup with 200ml of water, in which five out of the ten cups had the caffeine pill ( dissolve in water before giving to subject)

In the solid-liquid extraction all water soluble components were sepreated along with the caffeine including the tannins. To further isolate the caffeine and obtain a purer product it was necessary to add sodium carbonate(Zhao et al. 208). This acidic- base reaction (tannins being the acid electrophile and sodium carbonate the base nucleophile) forms conjugate base phenolic salts. Tannins are acidic and thus have an–OH group directly bound to their aromatic ring the addition of a weaker base allows for the deprotonation of said –OH group. Then when the methylene chloride was added the tannins, now a phenolic salt, were insoluble thus resulting in the formation of two layers (organic and aqeous). The aqeuous layer now contains the tannins and chlorphyll and the organic layer the caffeine. This occurs because caffeine is more soluble in the methylene chloride and thus is separtaed into the same layer and the tannin salts and chlorophyll which are insoluble in the methylene chloride remain in the aqeous layer. The organic layer is extracted and undergeos this same washing process again in order to extract the maximum amount of product. Once enough caffeine was extracted a drying agent of anyhydrous sulfate was added to remove any of the excess water in the organic layer and placed in a hot chamber to evaporate off the methylene chloride. The remaining crystals underwent recrystalization to obtain a pure substance. (Zhao et al. 208).

Based on my data, I think my isolation was somewhat of a success and in some ways not. I was able to obtain a pure recovery from the crude caffeine of 21.46%. It is not significant amount, but it seemed to be enough. A reason for some loss in my data was that some of the crystals were lost in the process of removing the inner tube. In addition, although I was unable to perform the NMR, I perform the IR, but my spectra resemble more like a blank. I obtain 0.05 grams of pure crystal caffeine but it could be that during my removable of the inner tube that when both of the tube accidently bumped that I lost some of the crystals, which resulted in not enough caffeine for me to get an IR spectra with all the peaks.

First, saturate the TLC trough with 30 ml of ethyl acetate: methanol solution for 10 mins. Next, spread the silica gel into into a 0.2 micrometer film over the Aluminum plate. Then, to dry the plate for usage, heat the plates in an oven at 110 Celsius for 5 min. Apply the samples 1 cm above the base of the plate using a sample applicator, along with nitrogen gas to allow the bands to simultaneously dry. Place the TLC Plate into the chromatography trough, and allow the plate to develop until the 10cm mark. Follow up by scanning the TLC plate in a densitometer to obtain a chromatogram of the separated samples. The Peak of caffeine observed on the chromatogram can be matched to the real plate and be scraped off for the retrieval of caffeine.

Who has the same solid that I have? Submitted by: Leslie Tran October 11th, 2017 Abstract: The properties of an unknown compound were determined and used to identify which other groups in the lab section had the same unknown compound. Using a variety of tests such as determining the relative solubility of the unknown, its relative melting point, the electrical conductivity of the substance and its aqueous solutions, its appearance in flame, its reactivity, and the acidity/basicity of the aqueous solutions, these observations were used to compare with another unknown compound.

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.