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
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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
Objective: The main goal of this lab is to learn how separation of binary liquid mixtures is performed. Especially when the two liquids have boiling points varying by about 30° C. Hexane can be separated from toluene in this experiment because of the difference in their boiling points. Since toluene has a higher boiling point, it will left at the bottom while the hexane starts to boil out and collect in the Hickman still. GC measurements help us in determining how accurate our data is by making a graph of the amount of hexane and toluene in each fraction. Also this lab gives experience with semi-micro
The purpose of this lab was to determine the limiting reactant in a mixture of to soluble salts and the percent composition of each substance in a salt mixture.
The purpose of this experiment is to familiarize oneself with the general procedures determining a partition coefficient at the microscale level and learn in weighing milligram quantities of materials on an electronic balance, the use of automatic pipets, the use of transfer pipet, and the use of a vortex mixer. Also, to familiarize oneself with extraction
1.) Briefly explain the concept of steam distillation. What is the difference between a simple distillation and a steam distillation? When a mixture of two immiscible liquids are distilled it is referred to as codistillation. This process is referred to as steam distillation when one of the liquids is water. This distillation is used to separate organic liquids from natural products and reaction mixtures in which the final product results in high boiling residues such as tars, inorganic salts, and other relatively involatile components. It is useful in isolating volatile oils from various parts of plants and not useful in the final purification of a
Whereas for simple distillation, the compounds need to be around 80C apart in order for proper separation to occur. Thus, cyclohexane and toluene were not able to be properly separated since the boiling point for cyclohexane was 80.74C while the boiling point of toluene was 110.6C—there two boiling points are fairly close to one another. Thus, the mole fraction for cyclohexane and toluene were fairly low when compared to cyclohexane and
The boiling range of the 1-pentyl ethanoate distillate was approximately between 149-151°C. This was indicated by the formation of the distillate and when the mixture of the purified 1-pentyl ethanoate started to vigorously
Distillation is a method of separating two volatile chemicals on the basis of their differing boiling points. During this lab, students were given 30 mL of an unknown solution containing two colorless chemicals. Because the chemicals may have had a relatively close boiling point, we had to employ a fractional distillation over a simple distillation. By adding a fractionating column between the boiling flask and the condenser, we were able to separate the liquids more efficiently due to the fact that more volatile liquids tend to push towards the top of the fractionating column, thereby leaving the liquid with the lower boiling point towards the bottom. After obtaining the distillates, we utilized a gas chromatograph in order to analyze the volatile substances in the gas phase and determine their composition percentage of the initial solution. Overall, through this lab we were able to enhance our knowledge on the practical utilization of chemical theories, and thus also demonstrated technical fluency involving the equipment.
The purpose of this lab was for the student to get involved with his or hers new lab kit as well as being able to know, identify and use each other tools provided in the kit. Another key learning aspect of this lab is to teach the student how to measure properly the many units in the SI system. I will be using laboratory dilutions, measurements, and weights to then calculate using algebraic formula.
Dispense .5 mL water into the already weighed conical vial, replace cap and face insert on its down side.
The purpose of this experiment was to separate a two component mixture using fractional distillation. Distillation is a process of vaporization than condensation of a substance, used primarily to separate substances from a mixture when there are different boiling points. Fractional distillation is when the mixture has multiple substances with similar boiling points, and a fractional column is used to create multiple vaporization/condensation cycles. Fractional distillation is important when two or more substances need to be separated, but they have similar boiling points.
The experiment will involve changing the oven temperature, the number of static cycles, length of static cycles, and the volume of solvent used in the process, which are all ratio variables except for oven temperature, which is an interval variable. The process will give me lots of quantitative data to compare and look at, so instead of doing each test individually, I will be using the Minitab software’s design of experiment program to help limit the amount of testing I must do. I can do this by entering in my parameters and their ranges, and the program will give me specific parameter levels to tests that will help it generalize the results as a whole. Then, using those particular parameter levels, the ASE process is done and followed by TE on the resulting liquid. The TE process will help me find the percent mass of residue from the original sample.
The purpose of this lab is to test substances and to determine the physical and chemical properties of substances.
A good yield of isopentyl acetate was obtained during this experiment. Loss of the product was likely through transferring liquid from separatory funnel to the Erlenmeyer flask and residual material left in the distillation flask. Using an organic solvent like benzene or cyclohexane as a transfer agent would improve the yield, since their boiling points were around 80 oC and could be easily separated from the final product through simple distillation. However this
Stage 1: Oxidation of Toluene to Benzoic acid. • Toluene + Oxygen → Benzoic acid + Water. • Catalyst: Cobalt Naphthenate. • Operating conditions: 150°C and 3 atms.
By recording the temperature and distillate obtained during fractional distillation, a graph was plotted. At each point on the graph where temperature plateaus, a boiling point of a component of the unknown binary solution was reached. The graph obtained was ideal because two boiling points were determined to be around 82˚C and 124˚C. By comparing the boiling points to the list of known solvents, the first component was identified to be cyclohexane with