Distillation experiment? A student carried out a simple distillation on a compou
ID: 895572 • Letter: D
Question
Distillation experiment?
A student carried out a simple distillation on a compound known to distill at 124degreeC and reported a boiling point range of 116-117degreeC. Gas chromatographic analysis of the product showed the product was pure, and a calibration of thermometer indicated the thermometer was accurate. What procedural error might the student have made in setting up the distillation apparatus? A mixture of toluene, benzene, and 1,2-dimethylbenzcnc (ortho-xylene) is injected on a gas chromatography column. Predict the sequence of retention times indicating which compound will have the shortest, middle, and longest retention time.Explanation / Answer
2. SInce compound is pure and therometer is showing accurate reading, only problem with thermostat (temperature providing source) and runiing water (used for cool the coloumn).Generaly a cmpound used to distill near to its boiling point.
3. The lower the boiling point is, the shorter retention time usually is because the compound will spent more time in the gas phase.
Touene boiling point = 110.6 0C
benzene boiling point = 80.1 0C
1,2-dimethyl benzene boiling point = 140 0C
Shortest retention time = Benzene
Middle retention time = Toluene
Longest retention time = 1,2-dimethylbenzene