Chemistry 12
12/Oct/2011
Titration- Analysis of Aspirin Tablets
Objective: Determine the percentage of aspirin (acetylsalicylic acid) present in two different commercial tablets by titrating the solution with a base. Also determine whether the aspirin is a strong or weak acid according to the Bronsted- Lowry and Lewis theories and deduce the formula of the acid- base reaction.
Independent Variable: The amount of base (NaOH) in moles that are needed to neutralize the solution.
Dependent Variable: Percentage of aspirin (acetylsalicylic acid) found in each tablet.
Materials:
* Balance * 2 aspirin samples from different brands * 50 cm3 conical flask * 10.00cm3 of 95% alcohol * 0.100 mol dm-3 sodium hydroxide * Phenolphthalein
…show more content…
H804 | | |
Percentage of aspirin: 0.5207 g | X | 100% | / | 0.100 g | = | 520.65 % C9H804 |
Percent Uncertainty: 0.10 ml | x | 100% | / | 28.90 ml | = | -+ 0.35% | 0.001 g | x | 100% | / | 0.603 g | = | -+ 0.17 % |
-+ 0.35% | + | -+ 0.17 % | = | -+ 0.52% |
Trial 3
NaOH needed to neutralize: 27.90 ml NaOH | 1 L | 0.10 mol NaOH | = | 0.00279 mol NaOH -+0.11ml | | 1000 ml | 1 L NaOH | | | |
Grams of Aspirin: 0.00279 mol NaOH | 1 mol C9H8O4 | 180.157 g C9H804 | = | 0.5026 g C9H8O4 | | 1 mol NaOH | 1 mol C9H804 | | |
Percentage of aspirin: 0.5026 g | X | 100% | / | 0.100 g | = | 502.64 % C9H804 |
Percent Uncertainty: 0.10 ml | x | 100% | / | 27.90 ml | = | -+ 0.36% | 0.001 g | x | 100% | / | 0.599 g | = | -+ 0.17 % |
-+ 0.36% | + | -+ 0.17 % | = | -+ 0.53% |
Aspirin B
Trial 1
NaOH needed to neutralize: 5.30 ml NaOH | 1 L | 0.10 mol NaOH | = | 0.00053 mol NaOH -+0.11ml | | 1000 ml | 1 L NaOH | | | |
Grams of Aspirin: 0.00053 mol NaOH | 1 mol C9H8O4 | 180.157 g C9H804 | = | 0.0955 g C9H8O4 | | 1 mol NaOH | 1 mol C9H804 | | |
Percentage of aspirin: 0.0955 g | X | 100% | / | 0.100 g | = | 95.48 % C9H804 |
Percent Uncertainty: 0.10 ml | x | 100% | / | 5.30ml | = | -+ 1.89% | 0.001 g | x | 100% | / | 0.217 g | = | -+ 0.46 % |
-+ 1.89% | + | -+ 0.48 % | = | -+ 2.35 % | Trial 2
NaOH needed to neutralize: 5.60 ml NaOH | 1 L | 0.10 mol NaOH | = | 0.00056 mol NaOH -+0.11ml | | 1000 ml | 1 L NaOH | | | |
Grams of
The goal of this experiment was to find out active chemical components in Anacin and Tylenol, using Thin Layer Chromatography technique. This technique uses the difference in the intermolecular forcer and polarity to separate mixtures. Comparing Rf values were then used to determine the active chemical components in the two analgesics. The overall result was that Acetaminophen exists in Tylenol and Acetylsalicylic Acid exists in Anacin.
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.
This experiment involved three steps: synthesis of aspirin, isolation and purification, and the estimation of purity of the final product. The synthesis involved the reaction of salicylic acid and acetic anhydride in the presence of a catalyst, phosphoric acid, H3PO4. When the aspirin was prepared, it was isolated and filtered. The percentage yield of the synthesis was calculated to be 78.42%. The experimental melting point range of aspirin was determined to be 122 -132°C. Due to its wide range, and lower value than that of the theoretical melting point of 136°C, it was
The goal of this experiment was to synthesize aspirin. In this experiment aspirin, also known as acetylsalicylic acid, was synthesized from salicylic acid and acetic anhydride. In the reaction the hydroxyl group on the benzene ring in salicylic acid reacted with acetic anhydride to form an ester functional group. This method of forming acetylsalicylic acid is an esterification reaction. Since this esterification reaction is not spontaneous, sulfuric acid was used as a catalyst to initiate the reaction. After the reaction was complete some unreacted acetic anhydride and salicylic acid was still be present in the solution as well as some sulfuric acid, aspirin, and acetic acid. Crystallization, which uses the principle of
The independent variable for the experiment was the paper towels. The dependent variable was the absorbency and strength. The constants for the experiment were the size of the paper towels that were used, the amount of water, the size of the beaker, the size of the cylinder and the amount of the weight.
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.
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.
The purpose of this lab was to synthesize aspirin, determine the theoretical yield, compare the percent yield to the theoretical yield and test the purity of aspirin by adding Iron (III) chloride to the product.
Variables: In this experiment, the temperature (in degrees Celsius) of the chemicals is the independent variable. To change the temperature, the materials are placed in a bath of water being heated by a hotplate.
Independent variable: We will change the amount of drops of Hydrochloric acid added to the Amylase. ( 5 drops, 10 drops, 15 drops)
In this lab a acid-base indicator phenolphthalein was used to determine endpoint of a reaction HCl(aq) and KOH(aq). At the end point all of the HCl(aq) would have reacted with KOH(aq), and the pH becomes 7. The phenolphthalein would changed colours from colourless to pink indication when enough KOH(aq) was added. The purpose of numerous trials was to use the average volume of the 3 trials with similar measurements.