Distillation of Cyclohexane-Toluene: Methods and Results
School
Northeastern University**We aren't endorsed by this school
Course
CHEM 2314
Subject
Chemistry
Date
Dec 11, 2024
Pages
5
Uploaded by ChancellorRainHeron38
Experiment #5Distillation and Boiling PointYujung JunLab Partner — Sarah GontowskiTeacher — Nicole SnyderDate Performed — February 13, 2024Date Due — February 20, 2024
Experimental objective: Distill cyclohexane-toluene mixture through simple and fractionaldistillation and generate respective graphs of volumes and temperatures.Reaction Equations:Reagents usedProcedure:Simple DistillationAfter setting up a hot plate and sand bath, the apparatus was set up according to instructions,making sure the connections are sealed using an o ring, and the thermometer is slightly above thehickman. Into a round bottom flask a boiling chip, 4.0 mL of cyclohexane, and 4.0 mL of toluenewere added and then attached to the apparatus slightly buried in the sand. With the heat at 7, orroughly 300°, the flask was heated. Once distillate formed the sidearm cap was removed and theliquid was drawn out using a syringe, recording the amount drawn and the temperature for eachvolume. This step was repeated until around 1 mL was left in the flask.Fractional DistillationAfter setting up a hot plate and sand bath, the apparatus was set up according to instructions,with the copper filled condenser. Into a round bottom flask a boiling chip, 4.0 mL ofcyclohexane, and 4.0 mL of toluene were added and then attached to the apparatus buried in thesand. With the heat at 7, or roughly 300°, the flask was heated. Once distillate formed thesidearm cap was removed and the liquid was drawn out using a syringe, recording the amountdrawn and the temperature for each volume. This step was repeated until around 1 mL was left inthe flask.
Observations:Experimental DataSimple DistillationFractional DistillationAmount mLWithdrawnTotal mLWithdrawnTemperature(°c)Amount mLWithdrawnTotal mLWithdrawnTemperature(°c)0.20.2760.60.6720.40.6800.20.8720.20.8820.61.4770.41.2830.51.9770.51.7840.22.1770.72.4850.42.5790.42.8860.22.7790.43.2870.43.1790.33.5880.23.3790.54.0890.23.5780.54.5890.23.7760.24.7900.13.8780.55.2930.13.9820.35.8940.14.084---0.14.187---0.14.287---0.14.388Table 1.Amount withdrawn, total amount withdrawn, and respective temperature forsimple and fractional distillation.
Characterization:Figure 1.Figure 2.Figure 3.Figure 1. Graph generated from data from simple and fractional distillation with total mL drawn,x, versus temperature, y. Figure 2. Graph generated from data from simple distillation with anoverall positive linear trend once temperatures reached roughly 78°c. Figure 3. Graph generatedfrom data from fractional distillation with an overall positive exponential trend.Conclusion:The distillation of cyclohexane-toluene was carried out successfully producing resultsclose to 4, fractional distillation being closer. Though the percent yield was not collected there isa strong indication that the final product that was collected was cyclohexane becausecyclohexane has a lower boiling point of 80.74°c as opposed to toluene’s boiling point of110.6°c.The graph generated from the data tables aligned with the expected graphs with simpledistillation producing a positive linear slope and fractional distillation with two different periodsof plateau and exponential growth. The amount of mL drawn increased exponentially oncetemperatures neared hit 75°c, going from 1.5 mL to 3.5 mL and began to slow from 80°c to 88°c.Fractional distillation produced less liquid in comparison to simple distillation which is accurateas one round of simple distillation is similar to three rounds of fractional distillation in terms ofproduct purity. If correct, the final product for the fractional distillation should have a higherconcentration of cyclohexane.
References:Schoffstall, Allen M., Barbara A. Gaddis, and Melvin L. Druelinger. Microscale and MiniscaleOrganic Chemistry Laboratory Experiments; 2𝑛𝑑ed.; New York: McGraw-Hill HigherEducation, 2004. Print; pp 90-91, 270-281.