Distilling a Mixture of Cyclohexane and Toluene Essay

Time) because it had a correlation closest to 1. All three orders were graphed and a linear regression was used to see which graphed order was closest to 1. The order was determined by comparing the concentration and time to the mathematical predictions made using the integrated rate laws. Analyzing each graph and finding each correlation helped determine which graph was closest to 1. The more concentrated a solution is, the higher the absorbance of that solution. This is due to Beer’s Law. The law measures the absorbance of a solution by determining how much light passes through a solution. As the concentration of a solution increases, fewer wavelengths of light are able to pass through the concentrated solution. The absorbance at 60 seconds was 0.573 (Figure 1: Table1). To calculate the concentration (molarity), the Beer’s Law equation was used, Abs = slope(m)+b. Plugging in what is known into the Beer’s Law equation resulted in 0.573 = 3.172e+004 + 0, where the concentration is determined by M = 0.573-0/ 3.172e+004. So, the concentration at 60 seconds using the equation (M = 0.573-0 / 3.172e+004) was 1.824e-5 M. The 1st order graph resulted in k=0.006152 (Figure 1: Graph 1). Other groups also resulted in their decolorization of CV to be the 1st rate

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

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 Beers Law calibration experiment used many concentrations of crystal violet solutions. Each of these solutions were test and analyzed in order to determine the absorbance of each concentration The results were than graphed and produced a slope of 1.00E05 with an intercept of -2.21E-02.

5. The degree of precision was to 3 significant figures obtained with the spectrophotometer. The major source of error in our experiment was not calibrating the spectrophotometer with distilled water.

Distillation of the first product began at 83 °C. A Pasteur pipette was used to remove 1-ml of the distillate into a vial. A second vial was filled with distillate until it reached 1-ml. As the second vial is being filled, observe the temperature and remove the apparatus from the heat source if there is an observed drop in temperature.

Distillation. Transfer the clear liquid to a dry 25-mL round-bottom flask using a Pasteur pipet. Add a boiling stone and distill the crude t-pentyl chloride in a dry apparatus. Collect the pure t-pentyl chloride in a receiver cooled in ice. Collect the material that boils between 78°C and 84°C. Weigh the product and calculate the percentage yield.

Simple distillation is a separation technique which can be used to separate and purify distillates from a liquid mixture which ideally contains one volatile and one non-volatile compound. If such ideal conditions are not possible—as is usually the case—then simple distillation can be applied as long as the liquid in question is composed of compounds that differ in volatility such that their boiling points differ by at least 40 to 50 degrees Celsius. Because

3. The spectrophotometer was set at 420nm. Distilled water was also used as the ‘blank’.

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

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 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

Figure 1 is a distillation graph of temperature in degrees Celsius vs volume of distillate in milliliters.

By determining and examining the average density and the average boiling point of the unknown liquid, it appears that the unknown liquid is methanol. The average boiling point of the unknown liquid is calculated to 69.8°C and its average boiling point is near the boiling point of ethanol, which is 64.7°C. While these values are not extremely close, we see further similarity regarding the densities. The average density of the unknown liquid is calculated to 0.7574 g/mL and the density of methanol is 0.791 g/mL. However, there were calculation errors while performing the experiment during trial 3 when using the volumetric pipette and during trial 1 when using the burette.

In this part of the column, the main separation that occurs is between Benzene and Toluene, which is the lightest component and the middle component. The presence of p-Xylene at this part of the column is low and irrelevant. Therefore the light key is Benzene and the heavy key is Toluene. Since the required mole fraction of Benzene in the distillate is 99.5%, the allowable “impurity” in the distillate is only 0.5%. Since p-Xylene is a heavy component, any p-Xylene present in the SRCT-2 column will go into the bottoms product of the column. Therefore all the 0.5% in the distillate will be Toluene, so specify the heavy key in the distillate to be 0.005. For the light key in the bottoms, it can vary depending on the total impurity level in the side stream. Since the specified Toluene purity is 91%, there is a total of 9% impurity in the stream. Therefore an initial guess of 0.045 can be taken as the mole fraction of light key in the bottoms. This will give a minimum reflux of 2.43 and a reflux of 2.9 is specified. The conditions at which the product streams SRCT2 Distillate and SRCT2 Bottoms is produced can be seen on table 6. The shortcut column can be seen on figure 35.The distillate stream in this SRCT-2 column represents the distillate product that will be produced and the bottom product represents a portion of the side product that is