S Separating mixtures

Question 1

What is filter paper, what does it do, and what is it used for?

Answer 1

Filter paper allows for a liquid to pass through it but does not allow an insoluble solid to pass through it. It is used to separate a solid that does not dissolve in water from the water itself.

Question 2

Definition of filtration?

Answer 2

Filtration is the method of separating an insoluble solid from a liquid using a material that allows the liquid to pass through but not the solid.

Question 3

List examples of filtration and what they do.

Answer 3

A coffee filter is a piece of paper that separates the coffee solution from the coffee grounds.
Surgical masks used by surgeons in the operating theatre let the air through but trap the germs.

Question 4

Give an example of an experiment involving filtration and list the conclusions of the test.

Answer 4

To separate a mixture of water and soil using filtration.
Conclusion:
Filtration may be used to separate a mixture of water and soil.

Question 5

What is the solid left on the filter paper called?

Answer 5

The solid remaining on the filter paper is called the residue which means what is left behind.

Question 6

What is the clear liquid that passes through the filter paper during the filtration of soil and water experiment?

Answer 6

The clear liquid that passes through the filter paper is called the filtrate

Question 7

Definition of Filtrate?

Answer 7

The filtrate is the liquid that has been filtered, that is, the liquid that has passed through the filter paper.

Question 8

What is evaporation?

Answer 8

It is the changing of a liquid to a gas.

Question 9

Give an example of an experiment and what evaporation is used for in the experiment? List the conclusions of this test as well.

Answer 9

We use evaporation to separate a solid (salt) from the water in which it is dissolved.
To separate sodium chloride (common table salt) from a solution of sodium chloride in water.
Conclusions:
The salt remains behind in the evaporation basin.
The water has evaporated into the air.
Evaporation is used to separate salt from a solution of salt and water.

Question 10

Where is sodium chloride found and in what form?

Answer 10

Sodium chloride is found in the earth in the form of rock salt.

Question 11

What does rock salt consist of and what is it used for and why?

Answer 11

Rock salt consists of sodium chloride mixed with sand and soil. Rock salt is spread on icy roads in the winter because it is used to melt the ice and give a better grip on the road surface.

Question 12

Give an example of filtration AND evaporation used in a scientific experiment and list the conclusions of it.

Answer 12

To separate salt (sodium chloride) from rock salt using filtration and evaporation.
Conclusions:
Pure salt is left in the evaporation basin.
Sand is left behind on the filter paper.
Pure salt can be separated from rock salt using filtration and evaporation.

Question 13

What is condensation?

Answer 13

Changing a vapour back to a liquid is called condensation.

Question 14

What is a condenser?

Answer 14

the apparatus which cools the vapour to a liquid is called a condenser.

Question 15

Who invented the condenser?

Answer 15

Justus von Liebig invented the condenser.

Question 16

What is distillation?

Answer 16

Distillation is the vapourising of a liquid by boiling it and then condensing the vapour by cooling it.
(Evaporating a liquid followed by condensing the vapour)

Question 17

Give an example of distillation used in a scientific experiment, explain what will happen, and list the conclusions of it.

Answer 17

To obtain a sample of pure water from seawater.
You will heat seawater in a distillation apparatus and then the water will be converted to steam which will be condensed back into pure, distilled water.
Conclusions:
Pure water is formed in the conical flask.
Distillation is used to separate pure water from seawater.

Question 18

Definition of distillate

Answer 18

The distillate is then purified liquid produced by condensation from vapour during distillation, that is, the product of distillation.

Question 19

What does the word chromatography mean and what was it first used for?

Answer 19

the word chromatography means colour writing. It was first used to separate coloured materials from plants.

Question 20

Definition of Paper chromatography and explain it.

Answer 20

Paper chromatography is a method of separating mixtures of substances in a solution. The solvent in which the substances are dissolved is passed along the length of paper and the dissolved substances separate out on the paper.

Question 21

Give an example of chromatography in a scientific experiment, explain what will happen, and list the conclusions of it.

Answer 21

To separate the dyes in a sample of ink using chromatography.
Conclusions:
Chromatography can be used to separate the dyes in a sample of ink.

Question 22

Explain the steps in the chromatography science experiment.

Answer 22

Filter or chromatography paper is put into a beaker so that it is touching the bottom. 3cm from the bottom of the paper, place a spot of ink on it, and pour in 2cm of water max. (Use water if the marker is water-soluble otherwise if it is permanent, use ethanol or propane.
When the solvent reaches the top of the paper, the paper is removed and allowed to dry. The ink has been separated into the dyes used to make the ink. If it has separated into only one colour, then the ink only consists of one colour.

Question 23

What is the paper showing the separated colours called?

Answer 23

the paper showing the separated colours is called a chromatogram.

Question 24

Definition of a chromatogram?

Answer 24

A chromatogram is the strip of paper on which the parts of a mixture have been separated by chromatography.