Discussion: Synthesis of Cyclohexene via Dehydration of Cyclohexanol Continued

The gas chromatography (GC), which measures purity, confirmed that the sample was not 100% pure because there were two peaks, of 0.663 (36.74%) and 1.084 (63.25%). Had it been pure cyclohexene there would have only been one peak. The bromine and potassium permanganate chemical tests were performed to distinguish the alkenes from alkanes. When bromine in dichloromethane was added to the cyclohexene product the solution did not change color. There was, however, a color change with cyclohexane. With each drop the solution went from light orange to brown. When potassium permanganate was added to cyclohexene the solution turned dark purple and became increasingly darker with each drop. The potassium permanganate formed two layers when added to the cyclohexane with the purple layer on top and clear layer on the bottom. Once again, the percent yield recovered through this experiment was 49.9%. This value could be due to not collecting all of the drops when transferring test tubes or not leaving enough time for the solution to dry after adding the CaCl2 pellets.