Orgo Lab 2
Simple and Fractional Distillation
Experiment II
Stancy Saji, 18 September 2014
Purpose
Experiment II involved two kinds of distillation techniques: simple and fractional. Simple distillation was done to separate ethyl acetate—which has a usual boiling point of 77º—from a less volatile component, while fractional distillation was done to distinguish an ethyl acetate/n-butyl acetate mixture, which has boiling points of 77º and 125 º, respectively.
Results and Discussion
As previously stated the standard boiling point for ethyl acetate is 77º. The data obtained resulted with the experimental boiling point being approximately 73º—which falls short of the standard value.
Liquid
Actual BP
Literature BP
Percent Error Calculation
% Error
Ethyl acetate
73º
77º
((73-77)/77) x 100
5.19%
The classic example of adding salt to water leads to a phenomenon named “Boiling Point Elevation.” Impurities form chemical bonds with the solvent in which they are, holding it together in liquid form. Breaking those bonds is difficult, causing a rise in boiling point. A 5.19% error could have occurred from the temperature probe being situated too high above the side-arm. If the bulb of the temperature probe is not low enough, the temperature of the vapor that is in equilibrium with the distilling mixture will not be measured.
Fractional distillation requires a more intricate set-up and a longer distillation process. This kind of distillation is ideal for liquids that boil about 25º fewer from each other.
Similar to what happened with simple distillation, the liquid with a lower boiling point condensed first. The lower line of the graph illustrates the boiling point range (BPR) of ethyl acetate, which varied by a one degree from the BPR from simple distillation. The higher line represents the BPR of n-butyl acetate which deviates from its standard by eleven degrees.
Liquid
Actual BP
Literature BP
Percent Error Calculation
% Error
Ethyl acetate
74º
77º
((74-77)/77) x
Experiment II
Stancy Saji, 18 September 2014
Purpose
Experiment II involved two kinds of distillation techniques: simple and fractional. Simple distillation was done to separate ethyl acetate—which has a usual boiling point of 77º—from a less volatile component, while fractional distillation was done to distinguish an ethyl acetate/n-butyl acetate mixture, which has boiling points of 77º and 125 º, respectively.
Results and Discussion
As previously stated the standard boiling point for ethyl acetate is 77º. The data obtained resulted with the experimental boiling point being approximately 73º—which falls short of the standard value.
Liquid
Actual BP
Literature BP
Percent Error Calculation
% Error
Ethyl acetate
73º
77º
((73-77)/77) x 100
5.19%
The classic example of adding salt to water leads to a phenomenon named “Boiling Point Elevation.” Impurities form chemical bonds with the solvent in which they are, holding it together in liquid form. Breaking those bonds is difficult, causing a rise in boiling point. A 5.19% error could have occurred from the temperature probe being situated too high above the side-arm. If the bulb of the temperature probe is not low enough, the temperature of the vapor that is in equilibrium with the distilling mixture will not be measured.
Fractional distillation requires a more intricate set-up and a longer distillation process. This kind of distillation is ideal for liquids that boil about 25º fewer from each other.
Similar to what happened with simple distillation, the liquid with a lower boiling point condensed first. The lower line of the graph illustrates the boiling point range (BPR) of ethyl acetate, which varied by a one degree from the BPR from simple distillation. The higher line represents the BPR of n-butyl acetate which deviates from its standard by eleven degrees.
Liquid
Actual BP
Literature BP
Percent Error Calculation
% Error
Ethyl acetate
74º
77º
((74-77)/77) x