Salicylic Acid Testing Observations
- The indicator that showed the presence of Salicylic Acid in the aspirin was the change in color from white to dark purple. The color that indicated the lack of Salicylic Acid was light yellow.
Conclusion
The weight of crude aspirin obtained from 4g of Salicylic Acid was 4.74g. After recrystallization, approximately 2.9g of recrystallized aspirin was obtained. After calculating the molar mass of Salicylic Acid and aspirin, the theoretically obtainable weight of aspirin was 5.217g. The percentage of theoretical crude aspirin obtained was 90.85%. The percentage of theoretical recrystallized aspirin obtained was 55.58%. During the Salicylic Acid testing, the crude aspirin tested positive by changing to dark purple color, which occurs due to the Salicylic Acid reacting with methanol and iron(III) chloride. After recrystallizing the crude aspirin, the aspirin was tested negative by changing to light yellow color. There is a possibility that these results are not entirely accurate due to human error. A few of the steps that require the use of a few drops of an chemical substance. However, there was no exact way to measure a few drops. As a result, it was possible to place too much or too little of the chemical substance, which can affect product of the reaction.
Questions
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What is acetylation? Into what general class of reactions does acetylation fall?
Acetylation replaces the alcohol functional group (-OH) with acetyl functional group (CH3CO-). The general class of reaction it falls into is
Aspirin, Caffeine and Salicylamide were extracted from an over-the-counter pain reliever (BC Powder). These components were separated by manipulating their solubilities by adjusting the acidity and basicity of the solution. By doing this, the three components were forced into conjugate acid (or base) forms, causing selective solubility in either an aqueous or organic solvent. These layers were then separated by use of a separation funnel. Once separated, the components extracted were characterized by measuring the melting point and performing a TLC analysis. Also, the recovered aspirin from the first part of the experiment was recrystallized and compared to that of the
Separation and Purification of the Components of an Analgesic Tablet. Cora Bruno, Lab Section E. Aspirin, Caffeine and Acetaminophen were separated from four analgesic tablets of Excedrin using extraction techniques. 5% wt/vol NaHCO3, 4M HCL, ethyl acetate and deionized water were used to separate the three active components. MgSO4 was used to dry each extraction. Aspirin was isolated using a hot water bath and weighed to determine the percent theoretical recovery and the actual percent recovery of aspirin. After separation, Aspirin (ASA), Caffeine (CAF), and Acetaminophen (ACE) were purified and identified using Thin Layer Chromatography (TLC). Standards and purified ASA, CAF, and ACE were spotted on the silica gel (stationary phase) of the
In experiment two, the drug Panacetin was separated by a series of chemical reactions into its three components: sucrose, aspirin, and an unknown active ingredient, either acetanilide or phenacetin. The purpose of this lab was to determine what percentages of each component is present in the pain-killer. The initial step was to dissolve Panacetin in dichloromethane. However, sucrose is insoluble in dichloromethane because organic molecules are soluble in organic solvents, and dichloromethane is an inorganic solvent, so only aspirin and the unknown dissolved. By using gravity filtration, sucrose was filtered from the solution and 0.30g of solid was collected.
Acetic Anhydride and p-Aminophenol were heated in a vial attached to an air condenser to synthesize crude acetaminophen, resulting in 0.097 grams (47.48% yield). The crude acetaminophen was then recrystallized in a solvent of water and methanol over heat resulting in 0.082 grams (39.61% yield) of pure acetaminophen. Melting points of both crude and pure acetaminophen were taken, and found to be 165.9 - 170.9°C and 168.2 - 171.5°C, respectively. The literature melting point of acetaminophen is 169.5 – 171.0°C, indicating that our final product was pure.
In determining the melting point range of the aspirin, a capillary tube (sealed at one end) was one-third-filled with the dried aspirin. The capillary tube and a thermometer were immersed in an oil bath. The temperature at which the solid started to melt and the temperature when the entire sample was completely liquefied were recorded as the melting point temperature range.
Ever wonder about the chemical makeup of tablets that people take for pain relief? Before a tablet can be successfully made, the limiting and excess reactants must be considered. The limiting reactant will affect the amount of the product that can be made. Another reason why the starting reactants must be determined carefully is to make reduce the amount of the reactant in excess so that reactants are not wasted. This experiment uses an Alka-Seltzer tablet. Alka-Seltzer dissolves in water and is an antacid and a pain reliever1. The Alka-Seltzer tablet has many uses such as relief of headaches, ingestion, heart burns, or even upset stomachs2. The active ingredients in an Alka-Seltzer tablet is aspirin, also known as acetyl-salicylic acid (C8H12O4), citric acid (C6H8O7), and sodium bicarbonate (NaHCO3)2. The aspirin in the Alka-Seltzer tablet helps with pain relief. Because of the acid-base chemistry (Brønsted-Lowry), citric acid and sodium bicarbonate produce O2, which makes the tablet fizz when it is dropped in liquid. The Brønsted-Lowry theory shows how the Brønsted-Lowry acid donates a hydrogen ion while the Brønsted-Lowry base accepts the hydrogen ions3. The remaining NaHCO3 that is in excess post reaction with the citric acid is what is used to neutralize stomach acid which helps relief heart burn2. The problem in
Both Aspirin and the Unknown are soluble in dichloromethane, due to their non-polar characteristics. To separate the two components, sodium bicarbonate was added (see figure 3). Sodium bicarbonate reacted with aspirin and converted it to a salt, also forming water and carbon dioxide. It was observed that the solution "fizzed" when this reaction took place, showing the release of carbon dioxide. The newly formed salt then traveled to an aqueous layer where it was soluble, while the unknown remained in the dichloromethane layer. The two layers were then separated. To collect an aspirin solid, the combination of the addition of HCl and the process of vacuum filtration helped to break down the salt and form a solid. Then the solid was placed in the Fisher Scientific Biotemp Oven to dry it to a constant mass of 0.091 g, 32.97% of the total composition. The
We made sure the solution is strongly acidic by testing it with litmus paper getting a pH of 2. We then cooled the mixture to room temperature swirling the flask occasionally in an ice bath. We collected the aspirin by vacuum filtration and washed the aspirin on the filter with cold distilled water. We let it air dry for 30-35 minutes and then weighed the aspirin. It weighed out at 0.513g. The unknown component was calculated and weighed at 0.738g.
Very little bit of aspirin will precipitate at pH 7, so the reported weight of aspirin will be low.
Aspirin is one of the most consumed painkillers created up to this date due to its reliability and low expense. It is often used to relieve minor aches and pains, reduce fever and as an anti-inflammatory medication. Due to its wide range of uses, the demand for this pharmaceutical is very high. As a result, manufacturers who produce this drug must be efficient in order to reduce the time taken to produce this drug and produce the in very high quantities.
0.1 gram of commercial aspirin was weighed in a tray and was then added to a second test tube containing 2.0 mL of Iron (III) chloride, which was measured using a 10 mL graduated cylinder, to test for phenols. This was repeated once more to validate results.
By using the pH paper to measure the solutions A through E it would point out what substance is an acid and which one was basic. Also, by adding Bromothymol blue and Phenolphthalein afterwards to the solution it would indicate what color it would turn to when mixed into an acid and a base.
The isolation of aspirin, acetaminophen, and caffeine from Excedrin utilized the differing acidities and polarities of the three compounds. Extraction involved separating the three components by reacting them with HCL and NaOH, while thin layer chromatography involved separating the isolated compounds on a TLC plate. The binder was the first component extracted; followed by aspirin, acetaminophen, and caffeine was extracted last since it is a neutral and polar compound. The entire process can be seen in figure 1. The most utilized methods of extraction were gravity filtration and vacuum filtration which are displayed in figures 3 and 4 respectively. These methods were utilized to separate compounds based upon their differing
The purpose of the lab was to synthesize aspirin and oil of wintergreen, and to determine its purity using recrystallization process, determining its melting point and using back-titration. To synthesize aspirin, salicylic acid and anhydride was used to drive the reaction to completion. In the synthesis of oil of wintergreen we reacted salicylic acid and methanol to produce methyl salicylate. This reaction is an example of a condensation reaction where the carboxylic acid and alcohol group combine to form an ester. In producing aspirin, we wanted to obtain the purest form, so we removed impurities such as unreacted salicylic acid and acetic acid. Acetic acid was removed by rinsing the sample in water because acetic acid is soluble in water. Salicylic, however, was removed by using the recrystallization process because it is insoluble in water. To recrystallize, we dissolved a sample of crude aspirin in warm ethanol and let it cool. Because aspirin is less soluble in ethanol than salicylic acid, it will crystallize out of the solution. To obtain the purified aspirin sample, we then filtered the solution to separate it from the impurities. To determine qualitatively the purity of the recrystallized aspirin, we determined its melting point using a melting point apparatus. Using the idea of freezing point depression, the presence of impurities will lower the melting point of the substance. Thus, by comparing the melting point to the actual
The purpose of this experiment is to separate a mixture of salicylic acid and naphthalene using extraction, recrystallization and sublimation techniques. Extraction is the separation of compounds from a mixture based on their relative solubilities in different solvents. Sublimation is the process of separation by which a substance transitions from the solid phase into the gas phase, skipping the liquid phase. Recrystallization involves dissolving a substance in an appropriate solvent then crystallizing it as it cools (impurities remain in solution). The melting points of the substances were determined in order to assess their purity and the percent recovery of pure naphthalene and salicylic acid were calculated. According to the results, the melting point of pure naphthalene was between 86°C -89°C range, whereas for pure salicylic acid was 167°C -170°C. Both determined melting points were higher compared to the literature value of 80.26°C and 158.6°C for pure naphthalene and salicylic acid respectively. Lastly, the percent recovery for pure naphthalene and salicylic acid were 17.7% and 71.2% accordingly.