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Wednesday, February 20, 2019

Distillation Lab Report

Data and Conclusions The purpose of this prove was to learn how to make use of distillment and gas chromatography to separate and happen upon different compounds from a given diverseness. There are several kinds of distillation methods. However, the method that we used in this experiment was computeal distillation. This method is used when seek to separate both different volatile compounds whose boiling aims differ by 40-50C or more than.If the boiling burdens are to a fault close, this method will not bring in because the two compounds will begin e vaporating at close temperatures and will sign down to the receiving flasks at relatively the same times. This will not pass water an ideal separation. The apparatus used for this type of distillation is longer than that of a simple distillation experiment because this kind of apparatus creates more in effect(p) separation. This happens because the fractional distillation apparatus is longer, and al brokens for several si mple distillations to occur at bottom the column itself to more accurately separate melteds.The inside of the column is state to declare theoretical plates, or equilibrium stages that are created by the vapor and liquid stages of a compound that create this accuracy. The column mustiness similarly be insulated with cotton and aluminum to prevent any heat bolshy that may lead to inaccurate temperature readings or even effect the vaporization of the different compounds. When heating the stillpot, flameless heating should be used along with a magnetic stirbar. This is important to control the temperature of the mixture and obligate the heat smooth and constant.Heating the mixture too fast could result in no fractionation in the column and lead to no separation. Likewise, if the mixture is heated too slowly, the vapors might now make it all the way to the condenser, and the liquid will fall back into the stillpot. If the mixture is heated correctly and constantly, the vapors should condense by dint of a condenser and into a receiving flask. This condenser should charter water running through it at all times to keep it cool and keep the condensed vapor flowing down into the receiving flask.As a whole, the complete apparatus works perfectly for two different volatile liquids with 40-50C boiling point differences because as the liquid with the lower boiling point is distilled out, the uplifteder boiling point liquid will remain in the stillpot as the other is evaporating and distilled. Then, it will be adequate to evaporate by and by as the temperature rises, after the other has more than completely distilled out. As I conducted this portion of the experiment, I noticed that while taking the three fractions, fraction A filled up the full 15 mL and act distilling through fraction B, and eventually stopped.Because of this, I hypothesized that all of fraction A and most of fraction B consisted of the low boiling point compound. As I raised the temperat ure of the hotplate, I was able to collect fraction C, and I predicted that it was composed of mostly the high boiling point liquid. To test this, the experiment called for the use of gas chromatography. The chromatography would not only show the relative concentrations of apiece compound in the fraction, but could also help confirm the acknowledgment of the compounds we thought were in the fractions based on the temperatures that each liquid boiled.Before trying to guess the correct compounds of the mixture, one must run each man-to-man fraction through the machine to clearly see the composition of each. bodge chromatography works because as the liquid runs through the machine, its different components run through and exit at different times due to changes of temperatures that measure high and low boiling points. The machine records these utilise peaks of retention time that identify these different components. After obtaining this data, there was enough information to choose a reasonable match for each of the components.Once both the fractions and the guessed compound were mixed, the retention recordings should not differ in the number of peaks because ideally the compound mixed should have the same retention time as one of the other antecedent peaks. If the compounds were to differ in the number of peaks, then it shows that another compound must be present with different properties. As I conducted this portion of the experiment, I guessed cyclohexane for my low boiling point liquid and toluene or heptane for my high boiling point liquid based on the fractional distillation observations.For cyclohexane I mixed it with fraction A, since it predominantly consisted of my low boiling point liquid, and observed two peaks in my results. Therefore I concluded that cyclohexane was the low boiling point liquid. However, for the second liquid I guessed heptane first, and my results showed three peaks. intentional that I had guessed wrong, I tested toluene mixe d with my fraction C and only got two peaks. The high boiling point liquid proved to be toluene. In conclusion, my results all matched the main ideas and theories presented in the experiment.From my results I was able to figure out the composition of each of the compounds in the initial mixture and compare them to those of the rest of the class. My results only varied by 3. 18%. When employ the two different methods of calculating the composition, the second method using the chromatography peaks was more accurate, and compared to the first method of assuming the ideal compositions, the results differed from the class average by over 10%. Based on the consistency of our class results using the second method, the two compounds proved to have been distilled using the proper method, and is strengthen by the use of gas chromatography.

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