Ethyl Acetate Lab Report

This experiment combined all the knowledge of the previous labs performed throughout the semester. An unknown mixture containing an organic acid or base and an organic neutral compound in nearly equal amounts needs to be separated to its separate components. An understanding of solubility, extraction, crystallization and vacuum filtration is necessary in order to

Part 1: Esters aromas are very distinct and often pleasant, they are often used in food aroma and fragrances.1 Esters chemical properties are distinguished by their low molecular weight and low boiling points, caused by their dipole-dipole and dispersion interaction.2 Esters are the result of a condensation reaction, in which a carboxylic acid, an alcohol, and an acid catalyst react to create a water molecule and an ester.

The mole is a convenient unit for analyzing chemical reactions. Avogadro’s number is equal to the mole. The mass of a mole of any compound or element is the mass in grams that corresponds to the molecular formula, also known as the atomic mass. In this experiment, you will observe the reaction of iron nails with a solution of copper (II) chloride and determine the number of moles involved in the reaction. You will determine the number of moles of copper produced in the reaction of iron and copper (II) chloride, determine the number of moles of iron used up in the reaction of iron and copper (II) chloride, determine the ratio of moles of iron to moles of copper, and determine the number of atoms and formula units involved in

Abstract: One mixture of two unknown liquid compounds and one mixture of two unknown solid compounds were separated, isolated, purified, and characterized by boiling point. Two liquid unknowns were separated, isolated, and purified via simple distillation. Then, the process of an acid-base extraction and washing were used to separate two unknown compounds into two crude compounds: an organic acid and a neutral organic compound. Each crude compound was purified by recrystallization, resulting in a carboxylic acid (RCO2H) and a pure organic compound (RZ). The resulting mass of the pure carboxylic acid was 1.688g with a percent recovery of 31.80%, the boiling range was 244-245 °C, and its density was 2.0879g/mL. The resulting mass of the pure organic solid was 2.4902g with a percent recovery of 46.91%, the boiling range was 52.0-53.4°C, and its density was 1.5956 g/mL.

In this experiment, an alkyne—diphenylacetylene—was prepared by a double dehydrobromination. Potassium hydroxide (KOH) and high heat were used to accomplish this. The precipitate of this reaction was collected by vacuum filtration. It was then washed with water and recrystallized using ethanol. The product was then isolated again before the weight was taken for further analysis of percent yield. The melting point was also taken to identify that it was the desired product.

Discussion As part of the experiment, the percent composition of each component of the mixture was calculated. 51% of the components were retrieved from filtration while 49% of the solvents were retrieved from dissolving the components in a solvent. The original mixture was one globular solid-like structure.

Note: Your prelab/lab report is to be done in your carbon copy lab notebook (sold in FIU bookstore)

Objective: The objective of this experiment is to use acid-base extraction techniques to separate a mixture of organic compounds based on acidity and/or basicity. After the three compounds are separated we will recover them into their salt forms and then purify them by recrystallization and identify them by their melting points.

1-butanol and ethanoic acid, and the product, 1-butyl-ethanoate exist in the same mixture due to the reflux setup, the reaction can never go to completion. Moreover, when isolating and purifying the ester, 1-butyl-ethanoate, some of the product will be lost. This will also occur when separating the ester in distillation, hence, it is not possible to obtain 100% of the product. So, if a theoretical yield were to be calculated, it would not be very accurate. The resulting value of the theoretical yield would most probably represent the maximum yield of the experiment as opposed to an actual yield of how much product will be obtained in the end. Therefore, it is not possible to get the theoretical yield in the experiment due to the lost of product (the ester) throughout the process in numerous occasions.

In this experiment, the relative rates of free-radical chain bromination where determined. Five arenes were used for this comparison along with two controls for each set. One set was kept in the dark while the other was put under light. This allowed for better observation of the reactions, as the light set would proceed fast to show which arenes reacted slowest, while the dark set would proceed slowly to show relative differences between the faster reacting arenes. The time it took for the arenes to react was recorded to determine the relative rates of the reactions.

Preparation of 3,3,5-trimethylcyclohexanol mixture: Isopropanol (12.5 mL, 163 mmol) and a KOH pellet were added to NaBH4 (17.8 mmol, 673mg) before 3,3,5 trimethylcyclohexanone (20 mmol, 3.16 mL) was added to the suspension. The reaction mixture was stirred (30 minutes, room temp.) and then added to brine (10.0 mL) in a separatory funnel. The product was extracted from the aqueous layer using 10% hexane (3 x10mL) before the combined organic layers were washed with brine (10.0 mL), dried with Na2SO4, and concentrated. The crude product was distilled using a vacuum aspirator to produce a clear, colorless liquid containing cis-3,3,5-trimethylcyclohexanol (1) and trans-3,3,5-trimethylcyclohexanol (2) (BP: ~105°C, 977mg, 38.6% yield), characterized

To prepare and purify an ester: 1-pentyl ethanoate, using pent-1-ol and ethanoic acid. An annotated reaction showing this reaction is shown below:

In this experiment, the concentration of acetic acid in a sample of vinegar was calculated. The sample used for the experiment was sample 4, created on 2/22/2017. The concentration was calculated by titrating the vinegar with NaOH. Unfortunately, NaOH does not form a pure solution so its concentration also had to be calculated. This was done by using it to titrate a solution of KHP, which does form a pure solution. Once the concentration of NaOH was known, it could be used to calculate the mols of acetic acid in a known volume of vinegar, giving us the concentration.

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.

In section IV, Experimental results are discussed and analysis is briefed. Finally, Conclusions are drawn.