C2.1.5 Distillation

Question 1

How does simple distillation work?

Answer 1

When the solution is heated, the solvent boils but the solute does not.
The solvent escapes from the solution in its gas state.
It is then cooled and condensed back to its liquid state by a condenser.

Question 2

What is a condenser?

Answer 2

A piece of apparatus that is kept cold using a flow of cold water.

Question 3

What does simple distillation rely on?

Answer 3

The solvent having a much lower boiling point than the solute.

Question 4

What substances does simple distillation separate?

Answer 4

A solvent from a solution.

Question 5

What substances does fractional distillation separate? And how many?

Answer 5

Two or more substances from a mixture in the liquid state.

Question 6

What does fractional distillation rely on and what special equipment is used?

Answer 6

It relies on each substance having a different boiling point and uses a fractionating column.

Question 7

Describe the separation of ethanol and water. Step one

Answer 7

In the fractionating column:

-The vapours condense on the inside surface, heating it up when the temperature inside reaches the boiling point of ethanol, ethanol vapour cannot condense any more, but water vapour can

Question 8

Step two of separating ethanol and water:

Answer 8

-Water droplets fall back into the flask, and ethanol vapour passes into the condenser.

Question 9

Last step of the separation of ethanol and water

Answer 9

-In the condenser, the ethanol vapour is cooled and condensed back to its liquid state. It drips into the collecting container.