V. Results and Discussion One of the objectives of this exercise is to synthesize acetylsalicylic acid (aspirin) from salicylic acid. The mechanism for this synthesis is through nucleophilic acyl substitution. Acetic anhydride was the acetylation reagent used with the salicylic acid. The mechanisms and the reaction involved in the synthesis are seen in the following figure. 1.00 gram of fine white salicylic acid powder was weighed in a clean, dry 125mL Erlenmeyer flask. 3mL of strong smelling, clear colorless acetic anhydride liquid was then measured in a 10mL graduated cylinder in the fume hood, and poured into the Erlenmeyer flask. The flask was then gently swirled while 5 drops of 85% phosphoric acid was added to the flask. During this time, the solution in the flask was whitish and cloudy. Phosphoric acid was used in the synthesis to become a source of H+ ions that would catalyze the reaction. Phosphoric acid is a liquid that doesn 't contain much water, since water will cause side reactions and reduce the yield of acetylsalicylic acid. A side reaction is the production of acetic acid from the water in phosphoric acid reacting with the acetic anhydride. Another reason for the use of phosphoric acid is that it creates a relatively strong conjugate base, since the acid catalysis step needs to be reversible. Sulfuric acid is also used in acetylsalicylic acid synthesis since it is 98% pure. In using concentrated sulfuric acid, there would be less of the side reactions,
Transformations Presented in E. Coli Using the pGlo Gene Introduction In biology, genetic transformations involve the transfer of a gene into an organism to give that organism a new gene to express (Blaber, 2004). Genetic transformations can be used for therapy, vaccinations, and in tissue renewal (Rivera,2014). In 1928, a man named Frederick Griffith discovered the term genetic transformations and their use (Griffiths,2000). To test these new genetic transformations a substance called pGlo is used to allow for replication and to see the results because of the bioluminescence.
In this diagram we can see that acetaminophen consists of a benzene ring core, with hydroxyl and amide functional groups in proxy. Benzene (C6H6) is a hydrocarbon composed of 6 carbon atoms (92.26% of the molecule) and 6 hydrogen atoms (7.74% of the molecule) with alternating double and single bonds (resonance bonds) and is aromatic because of this. Benzene is a natural part of petroleum, usually <1.0% by weight, but is found in many things used today. Benzenes most common use is to produce ethylbenzene, with over half of the benzene used in the production of ethylbenzene. Benzene is a clear, colourless and highly volatile liquid which is soluble in water at an average room temperature (23.5o).
After that, a spin vane was inserted into the vial while adding 0.75 mL of 1M H2SO4 solution. During the addition of the sulphuric acid, the solution was stirred at room temperature until the amino acid (L-Phe) completely dissolved. An ice bath was prepared and used for cooling the L-Phenylalanine solution at a temperature of 40C (a selected temperature lower than 50C). Once the solution was cooled, the first portion
Lab Report 5: Acetylsalicylic Acid (Aspirin) Synthesis Name: Divya Mehta Student #: 139006548 Date Conducted: November 19th 2014 Date Submitted: November 26th 2014 Partner’s Name: Kirsten Matthews Lab Section: Wednesday 2:30 L9 IAs Name: Brittany Doerr Procedure: For the procedure, see lab manual (CH110 Lab Manual, Fall 2014) pages 96-98. Wilfrid Laurier University Chemistry Department. Fall 2014. Acetylsalicylic Acid (Aspirin) Synthesis.
Aspirin is considered a “polydrug” due to its variety of uses stretching from pain-relief to disease prevention. Salicylic acid is derived from the bark and leaves of the willow tree. Salicylic acid belongs to a group of phytochemicals which have been shown to have positive effects on human health. Salicylic acid is a phenolic compound that can be found in a variety of plants and is a crystal organic carboxylic acid. However, it is more commonly viewed as the primary metabolite and active compound of acetyl salicylic acid, which has been used as an anti-inflammatory drug by physicians for over 100 years.
The specific purpose of this experiment is to determine the composition of vapor and liquid phases for different mixtures of a pair of volatile liquids using refractive values and distillation techniques involving the construction of two different types of phase diagrams. Moreover, these different phase diagram might be analyzed and compared individually in order to have a better understanding about the multiple types of phase equilibrium and phase change that occurs. For the procedure, the two components are benzoic acid and o-toluic acid. The first step of this experiment is to accomplish the part A: run samples A1 to A5 and B1 to B5. For this step, place a beaker of silicon oil on top of a hot plate until the temperature reaches 135 +/-
Introduction The purpose of this experiment was to synthesize para-chlorophenoxyacetic acid. The way that this acid is formed is through a SN2 reaction with chloroacetate and chlorophenolate. During a SN2 reaction, everything occurs in one step. The leaving group, which is usually electronegative, will fall off while the nucleophile attacks the back of the carbon.1
CLAIRE MUNTING 29/01/2018 Criterion C EFFECTS OF SURFACE AREA OF CALCIUM CARBONATE UPON RATE OF REACTION Calcium Carbonate Chips 1 Introduction: Within the current investigation, the effects of the surface area of Calcium Carbonate (CaCO3) in combination with Hydrochloric acid (HCl) upon its rate of reaction. CaCO3, commonly referred to as limestone, is an organic substance and is, in a sense, the crystallised “carbonic salt” of the element, calcium2. In addition to being a salt, the pH level of Calcium Carbonate is 9.91, and it is therefore, a basic substance, due to the fact that it is comprised of a pH level higher than 7, which is neutral3. HCl, however, is the bodily acid found in the stomach of human beings.
Arsenate can replace inorganic phosphate in step 6 of glycolysis that produces 1,3-bisphosphoglycerate instead of glyceraldehyde 3-phospahte. This yields 1-arseno-3-phosphoglycerate instead, which is unstable and quickly hydrolyzes, forming the next intermediate in the pathway, 3-phosphoglycerate. This is the same product that is normally formed in step 7. This is a problem because the product forms before it should and therefore does not reach the enzyme so the energy released cannot be harvested to generated ATP. Arsenate wastes energy by the uncoupling phosphotransfer reaction so its very POISONOUS.
The results of the phenol-sulfuric acid analysis conducted in this experiment suggest that the data acquired was relatively precise but inaccurate with respect to the given carbohydrate concentrations of the soda and Gatorade samples. Using a standard curve generated from a glucose solution with a known concentration, the carbohydrate concentration of the samples was determined (in terms of glucose) and a low coefficient of variation was calculated. However, a high percent relative error was apparent in the analysis of both samples. This may have been due to the fact that the analysis was conducted assuming glucose was the carbohydrate of interest, while, in fact, a significant portion of the monosaccharides would have existed as fructose (a
Introduction 1.1 Aim: To determine the kinetic parameters, Vmax and Km, of the alkaline phosphatase enzyme through the determination of the optimum pH and temperature. 1.2 Theory and Principles (General Background): Enzymes are highly specific protein catalysts that are utilised in chemical reactions in biological systems.1 Enzymes, being catalysts, decrease the activation energy required to convert substrates to products. They do this by attaching to the substrate to form an intermediate; the substrate binds to the active site of the enzyme. Then, another or the same enzyme reacts with the intermediate to form the final product.2 The rate of enzyme-catalysed reactions is influenced by different environmental conditions, such as: concentration
Aim: To find out the relationship between the greater concentration of sodium thiosulfate when mixed with hydrochloric acid and the time it takes for the reaction (the time it takes for the solution to turn cloudy) to take place and to show the effect on the rate of reaction when the concentration of one of the reactants change. Introduction: The theory of this experiment is that sodium thiosulfate and hydrochloric acid reach together to produce sulfur as one of its products. Sulfur is a yellow precipitate so, the solution will turn to yellow color while the reaction is occurring and it will continue until it will slowly turn completely opaque. The reaction of the experiment happens with this formula: “Na2 S2 O3 + HCL =
Acids are proton donors in chemical reactions which increase the number of hydrogen ions in a solution while bases are proton acceptors in reactions which reduce the number of hydrogen ions in a solution. Therefore, an acidic solution has more hydrogen ions than a basic solution; and basic solution has more hydroxide ions than an acidic solution. Acid substances taste sour. They have a pH lower than 7 and turns blue litmus paper into red. Meanwhile, bases are slippery and taste bitter.
Introduction The goal of the experiment is to examine how the rate of reaction between Hydrochloric acid and Sodium thiosulphate is affected by altering the concentrations. The concentration of Sodium thiosulfate will be altered by adding deionised water and decreasing the amount of Sodium thiosulphate. Once the Sodium thiosulphate has been tested several times. The effect of concentration on the rate of reaction can be examined in this experiment.
Abstract The unknown concentration of benzoic acid used when titrated with standardized 0.1031M NaOH and the solubility was calculated at two different temperatures (20◦C and 30◦C). With the aid of the Van’t Hoff equation, the enthalpy of solution of benzoic acid at those temperatures was determined as 10.82 KJ. This compares well with the value of 10.27KJ found in the literature.