Experiment: Cyclohexanone from Cyclohexanol aq Abstract: The primary objective of this experiment was to create cyclohexene from the dehydration of cyclohexanol with phosphoric acid. Through the use of simple distillation it was possible to separate the solution. The Agilent 7890A Gas Chromatography System was used to determine the purity of the distillate which verified the success of the separation. Introduction: Alkenes can be prepared by from alcohols by an acid catalyzed dehydration reaction. In the experiment a secondary alcohol (cyclohexanol) is heated with acid (phosphoric acid).
Distillation is used to purify a compound by separating it from a non-volatile or less-volatile material. When different compounds in a mixture have different boiling points, they separate into individual components when the mixture is carefully distilled. The boiling point is the temperature at which the vapor pressure of the liquid phase of a compound equals the external pressure acting on the surface of the liquid. The external pressure is usually the atmospheric pressure. Different compounds boil at different temperatures because each has a different, characteristic vapor pressure: compounds with higher vapor pressures will boil at lower temperatures.
This was so that the mussel samples would not go bad due to heat or harsh solvents. They were extracted with a mild solvent, and then concentrated by evaporation. The team found that the vapor was not toxic, but the residue after was. Other extractions were done to see how the residue separated when added with other mixtures of nonpolar solvents. In the toxic mussels, the visible light absorption spectrum revealed a pattern that was characteristic of phytoplankton pigments.
A binding material can be separated by dissolving the tablet in ether since three active ingredients are soluble. Then, aqueous K2HPO4 and KOH are used to extract the ether solution with the conjugate base of the Aspirin layer and the conjugate base of the Acetaminophen, respectively. The caffeine can be isolated from the left over layer by evaporating the ether. Two separated solutions form solid by acidifying with HCl and the solid residue can be collected by vacuum filtration. According to the Revell's lab experiment, aspirin, acetaminophen, caffeine recoveries are 60% or higher, <10% and <5%, respectively.
The purpose of the lab was to determine which reactant was the limiting reactant, and to see how much of the other reactant was used. The true molarity of a compound can be defined as the amount of moles per liter of that substance. The equation of this single displacement chemical reaction done during this lab is 2Al(s) + 3CuCl(aq) → 3Cu (s) + 2AlCl2 (aq). In the reaction, the solid Aluminum replaces the Copper in Copper (II) Chloride to produce solid copper, and Aluminum Chloride. In order to find which reactant is the limiting reactant, an equation based on the molarity of the Copper (II) Chloride may be used, or the products of the reaction may be observed.
Purpose: The reduction of carbonyl compounds is an important synthetic method to create alcohols. Aldehydes and ketones can be reduced by a variety of reagents to yield their respective alcohol products. Among the most useful reagents for accomplishing these reductions are the complex metal hydrides such as lithium aluminum hydride (LiAlH4 or LAH) and sodium borohydride (NaBH4). LAH and NaBH4 differ in their reactivities towards different classes of carbonyl compounds. LAH is highly reactive and will reduce acid chlorides, esters, carboxylic acids, amides, and nitriles as well as aldehydes and ketones.
Nitration of Methylbenzoate Aim: The aim of the experiment is to successfully perform the nitration of Methylbenzoate by the recrystalisation method and in doing so obtaining a melting point and the infra-red spectra graph of the product. Introduction: Methylbenzoate is an aromatic compound and it is structurally related to Benzene. It has an electron rich aromatic ring which makes it vulnerable to electrophiles this in turn making them react. A common electrophile is used in this reaction, which is the NO2+ nitronium ion. It is produced by reacting nitric acid and sulphuric acid simultaneously.
Micro – scale Reduction of a Ketone to an Alcohol: Benzophenone to Diphenylmethanol with Sodium Borohydride Abstract: Purpose of experiment 2.1 was to perform reduction reaction of benzophenone to diphenylmethanol with sodium borohydride as a reducing agent. The reducing agent was used in excess to ensure complete reduction of the carbonyl group. The product was isolated as a solid by filtration and its purity was checked using Thin Layer Chromatography with different ratios of mixture of polar and non – polar solvents and by checking its melting point, which was 520C - 620C. Infra – Red spectroscopy was not performed, however previously printed graphs were compared and analysed based on tables in Chemistry Laboratory Manual. Purpose of the Experiment: To produce diphenylmethanol from the reduction of benzophenone by using sodium borohydride as a reducing agent.
Although the salicin in willow bark has analgesic properties, purified salicylic acid was bitter and irritating when taken orally. Salicylic acid was neutralized with sodium to produce sodium salicylate, which was better-tasting but still irritated the stomach. Salicylic acid could be modified to produce phenylsalicylate, which was better tasting and less irritating, but released the toxic substance phenol when metabolized. Felix Hoffman and Arthur Eichengrün first synthesized the active ingredient in aspirin, acetylsalicylic acid, in 1893. In this laboratory exercise, you can prepare aspirin (acetylsalicylic acid) from salicylic acid and acetic anhydride using the following reaction: salicylic acid (C7H6O3) + acetic anhydride (C4H6O3) --> acetylsalicylic acid (C9H8O4) + acetic acid (C2H4O2) How to Make Aspirin - Acetylsalicylic Acid - Objectives & Materials First gather the chemicals and equipment used to synthesize the aspirin: Materials * 3.0 g salicylic acid * 6 mL acetic anhydride* * 5-8 drops of 85% phosphoric acid or concentrated sulfuric acid* * distilled water (about 50 mL) * 10 mL ethanol * 1% iron III chloride (optional, to test purity) *Use extreme caution when handling these chemicals.
0.200 g KOH .1 mol of KOH56.11 g= 0.00356 mol of KOH Given the 1:1 stoichiometry of the reaction, 2-naphthol is the limiting reagent Theoretical yield = 0.5 g Percent yield=actual yieldtheoretical yield .100% 0.3189 g0.5g .100% 63.8 % | Conclusion A 63.8% yield of nerolin was recovered in the reaction of 2-naphthol and ethyl iodide. Given the stoichiometry of the reaction being 1:1, 2-naphthol was found to be the limiting reagent. Since the percent yield was not very high, it is plausible to assume that some errors may occurred that contributed for the lower yield. Those errors may be caused by the incomplete dryness of the product, loss of product during extraction and wrong amount of reagents. If the experiment was to be