Fractional Distillation And Gas Chromatography Lab

Fractional Distillation and Gas Chromatography

6. Data and Results Reference Attached Pages

7. Discussion The purpose of this experiment was to identify the chemical constituents of an unknown solution and its ratio. The separation and purification of liquids can be done through 4 main methods: simple, fractional, steam, and vacuum distillation. For the purposes of this experiment, only fractional distillation was used. Fractional distillation, and other types of distillation, involves using the boiling points of chemicals to separate them into pure liquids. However, fractional distillation is only used when there is a liquid/liquid mixture where the boiling points of the two solvents are more than 40°-50°C apart. A liquid/solid mixture

First, the calculations were made with a lab member’s data. This is because the GC machine was broken during the very first week when the samples were produced from fractional distillation. Because of this, the GC portion of the experiment was pushed to the following week. During the week where the samples were sitting in the lockers, portions of the sample evaporated which made the calculations less accurate. The following week, gas chromatography was conducted but lots of lab members had questions and issues with the extraction experiment so the TA was unable to get through everyone’s GC. Because of this, the TA instructed the lab to use the data of one lab member’s data that was relatively

Although the correct results were obtained, there were still many problems with the experiment. As previously stated, the GC was not working the first week so GC portion of the experiment had to be pushed back a week. This caused portions of the sample to evaporate causing less accurate results. In addition, all the members of lab were told to expect that the first boiling point would be 81°C but the boiling point of one of the substances, acetone, was actually 56.5°C. Thus, the solution was boiled for too long and the B and C samples did not have the correct ratio of acetone to toluene. In addition, not everyone was able to get through the GC portion of the experiment due to complications in the extraction and recrystallization experiment. Thus, lab members were instructed to use one lab member’s data. Overall, the flawed data did have the correct boiling points so the unknowns were correctly identified. Also, the lab member’s data did have a relatively accurate ratio of acetone to toluene so the experiment was