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Toluene Synthesis Lab

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Objective:
The purpose of this lab is to separate a mixture and determine the percentages of each of the ingredients. Each substance will have a different boiling point due to its intrinsic properties and from that, we will be able to determine the purity of different products as we evaporate off the next level of product.
Experimental:
We created a 3mL sample composed of isopropyl acetate and toluene in a 1:1 ratio and put it into a Hickman still to heat. While heating the sample, we observed that the solution was having difficulty reaching a boil, so we wrapped it with aluminum foil and turned up the vacuum. At 91°C, a slightly opaque white solution began filling up the empty flask. As the distillate grew, we suctioned it out and placed …show more content…

Each fraction had a higher percentage of isopropyl acetate than toluene but the toluene gradually increased through the three samples. This is not feasible data since there is a large portion of toluene unaccounted for. The known retention time for toluene is given to us so the time for it to pass through the column should have been closer to 1.91 minutes and the isopropyl acetate should have been closer 1.67 minutes. Isopropyl acetate has a higher boiling point, so the first fraction should have had a very high percentage of isopropyl acetate and a relatively low percentage of toluene. The next fraction was heated to toluene’s boiling point so it should have had relatively equal percentages of isopropyl alcohol and toluene. The final fraction should have been almost completely toluene seeing as the initial and second fractions utilized most of the available isopropyl acetate. To calculate the peak area, the formula for triangle area is used which is 1÷2 of the base × the height of the triangle. The larger the area of the triangle, the more of the corresponding substance is present in the fraction. Then from those values, you can calculate the percentage of composition occupied by each substance. The formula is Area of single component÷total area × …show more content…

Simple distillation is more effective when the two components of a mixture have a difference in boiling point that is greater than 50°C. This large difference makes the need for theoretical plates non-existent since there is no need for multiple distillations per fraction. We can collect all necessary data from a simple distillation fraction using a gas chromatograph. The gas chromatograph vaporizes the injected sample and it begins to undergo partitioning. It is pushed into a small heated column that is coated in the liquid form of the sample. The longer the substance stays inside the column before passing over the heated wire, the longer the retention time is. The retention time is utilized to identify the substance, while the number of peaks shows how many substances are present, and the size of the peaks show how much percentage each substance occupies in a sample. The intrinsic properties of isopropyl acetate and toluene allow analysis of the provided data to become quite simple. Isopropyl acetate has a lower boiling point because it has a relatively low dipole moment and only one double bond. Thus, the intermolecular forces are relatively low in isopropyl acetate leading to a low boiling point. Toluene has a higher boiling point because the methyl group, attached to the benzene

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