Activity 11: Fractional Distillation

Question 1

A more efficient method of separation or purification of liquid mixtures than simple distillation

Answer 1

Fractional distillation

Question 2

The principle involved here is based on the use of a ___________ inserted vertically between the distilling flask and the condenser, allowing better separation of the components of a liquid mixture

Answer 2

fractionating column

Question 3

different types of fractionating columns

Answer 3

• Hempel column
• Vigreux column
• Spiral wire column

Question 3

• This column is most commonly used in laboratory.
• composed of a vertical glass tube or distilling column

Answer 3

Hempel column

Question 3

in this type of column, the glass tube does not contain any packing but is composed of a series of sharp indentations.

Answer 3

Vigreux column

Question 4

In this type of column, the wire inside is inert to most materials and serves as good conductor establishing an efficient heat exchange between column and surrounding.

Answer 4

Spiral Wire column

Question 5

Constricting the column at the bottom can cause ___________

Answer 5

“choking” of the column during distillation

Question 6

TRUE?FALSE.

Distill the mixture very slowly at a rate of not more than 2ml/minute.

Answer 6

TRUE

Question 7

Basing from the distillation curves, which method of distillation provided better separation? explain.

Answer 7

Fractional Distillation. thetemperature rise is initially very slow which means the distillate is almost purely ethanol., then abruptly rises resulting to wider temperature range a steeper slope indicating a more efficient separation.

Question 7

Basing from the ignition test which fractions represent higher concentrations of alcohol?

Answer 7

fractions 1-6

Question 7

basing from the distillation curves which method of distillation provided better separation? Explain.

Answer 7

fractional distillation. The temp. rise is initially very slow which means the distillate is almost purely ethanol, then abruptly rises resulting to wider temp. range and a steeper slope indicating a more efficient separation

Question 8

what is the role of fractionating column

Answer 8

the packing material in the fractionating column provide greater surface area on which the vapors can condense and the re-evaporate, recondense, essentially distilling the compound many times over yielding a vapor richer in ethanol