Steam Distillation: The isolation of limonene 1. Purpose The purpose of the experiment is to be familiar with the use of steam distillation, to learn how to extract an organic solvent and remove a volatile liquid by a rotary evaporator, and to determine the purity of the limonene. Steam distillation was used because it is a special type of distillation especially for temperature sensitive materials. Dichloromethane was used to extract the aqueous mixture. Magnesium sulfate was used to absorb water and simple filtration was used to remove magnesium sulfate.
Simple and Fractional Distillation of a Binary Mixture Introduction/Background – This experiment dealt with a 1:1 ratio of a stock mixture of cyclohexane and toluene. The aim of the experiment was to separate these two chemicals through the use of simple and fractional distillation. The separation of the two chemicals was possible because of the theory behind distillation. If there are two solvents, A and B, with two different boiling points, then they can be separated by evaporation and condensation. Knowing the different boiling points of the two liquids was useful in this experiment so that the sand bath could be heated to different temperatures to evaporate the two solvents.
And limiting reagent which is the reactant that is completely consumed when a reaction is run to completion. III. Summary of Procedure In this lab the first procedure was to measure the initial temperature of NaOCl and of Na2S2O3 and measure it with a thermometer and then record it. The same thermometer is used for measuring both solutions, but the thermometer should be washed with distilled water after the using it in one solution. Afterwards a small amount of NaOCl was added to the graduated cylinder.
The goal of the experiment is to synthesize a bromohexane compound from 1-hexene and HBr(aq) under reflux conditions and use the silver nitrate and sodium iodide tests to determine if the product is a primary or secondary hydrocarbon. The heterogeneous reaction mixture contains 1-hexene, 48% HBr(aq), and tetrabutylammonium bromide and was heated to under reflux conditions. Heating under reflux means that the reaction mixture is heated at its boiling point so that the reaction can proceed at a faster rate. The attached reflux condenser allows volatile substances to return to the reaction flask so that no material is lost. Since alkenes are immiscible with concentrated HBr, tetrabutylammonium bromide is used as a phase-transfer catalyst.
In order to understand the lab one must also understand endothermic and exothermic reactions. When a solid dissolves in water heat is either absorbed or released, which results in either an endothermic or exothermic reaction. An endothermic reaction is defined as the process in which energy, as heat, flows from the surrounding into the system. While an exothermic reaction is defined as the process in which energy, as heat, flows out of the system into the surroundings. When an endothermic reaction occurs, heat it taken in making the pack cool down, and in an exothermic reaction occurs heat is released making the pack warm up.
Once a solute is added to the solvent, solute molecules occupy the molecular surface space of the liquid, swing the evaporation process. If the solute is dissolved in a solvent, the number of solvent molecules near the surface decreases, thus vapor pressure of the solvent decreases. Why does this property change when the solute is increased? One use for vapor pressure lowering is in distillation. Distillation is a liquid purification process using heating and cooling.
Because of this, anhydrous sodium sulfate is used to remove the water from the solution. Aqueous sodium bicarbonate is used to neutralize the acid, resulting in the racemic mixture of methylcyclohexenes. To ensure that this process is successful one can administer unsaturation tests to determine if double bonds were formed. Compounds containing double bonds react with a red bromine solution and decolorize it. A similar reaction occurs when adding potassium permanganate, with an added brown precipitate forming.
The study of specific heat falls under the category of Thermochemistry which is further divided into the category of Calorimetry. An instrument called a calorimeter is used to measure specific heat. A piece of metal is placed in a container of water. This is then boiled. The piece of metal is then taken out of the boiling water and placed in a calorimeter which contains room temperature water.
The salts will be dissolved in distilled water by small quantities until the reaction reaches When ionic compounds dissolve in water, they either absorb energy from or release energy to the surroundings. If a chemical reaction absorbs heat from the surroundings, it is an endothermic reaction. If a solution releases heat to its surroundings, it is an exothermic reaction. The enthalpy of dissolution is the enthalpy change associated with the dissolution of a substance in a solvent at a constant pressure. The change in enthalpy relies on the concentration of the salt solution, because different concentrations will produce different enthalpies.
Therefore, acetic acid was used for this experiment. It reacted with the sodium hypochlorite to give hypochlorous acid, which thenreacted with the oxygen of the alcohol. Steam distillation was used to isolated product, and then was extracted into the distillate with ether with the addition of dying agent calcium chloride. Finally, the ether was removed to get the product, cyclohexanone with the "salting out" process. The process of salting out was used to separate cyclohexanone from the aqueous solution to purify the product.