Simple and Fractional Distillation of a Binary Mixture
This experiment dealt with a 1:1 ratio of a stock mixture of cyclohexane and toluene. The aim of the experiment was to separate these two chemicals through the use of simple and fractional distillation. The separation of the two chemicals was possible because of the theory behind distillation. If there are two solvents, A and B, with two different boiling points, then they can be separated by evaporation and condensation. Knowing the different boiling points of the two liquids was useful in this experiment so that the sand bath could be heated to different temperatures to evaporate the two solvents. Once the liquid was evaporated the vapor was collected and condensed in the condenser allowing the collection of said liquid.
When simple distillation occurred the liquid only evaporated and condensed one time as opposed to the fractional distillation. Fractional distillation was more accurate due to the fractionated column allowing multiple vaporization and condensation reactions to take place. Raoult’s Law was used in this experiment because it describes the vapor pressure that takes place in the experiment. The law states “The vapor pressure of a solution of a non-volatile solute is equal to the vapor pressure of the pure solvent at that temperature multiplied by its mole fraction.” (Clark) This means that the vapor pressure of a solution depends on the vapor pressure of the solutes making up the solvent. Dalton’s Law says that the total vapor pressure of a solution is equal to all of the individual vapor pressures that make up the solution. (Blauch) This law was also used in the lab due to the binary mixture of cyclohexane and toluene.
Experimental Section –
* Setup fractional distillation equipment
* Gathered 7mLof stock mixture
* Added four boiling stones
* Added heat to vial of 7mL of stock mixture
* 2-3°C per minute
* Collected 3.3mLof...