Seperating Mixtures

Question 1

What is filtration?

Answer 1

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

Question 2

How do you separate a mixture of water and soil using filtration?

Answer 2

1. Rinse a filter funnel and place a cone of filter paper inside
2. Pour in the water and soil solution against a glass rod into the funnel until the mixture has been filtered
3. The solid remaining is called residue
4. The liquid that passed through is called filtrate

Question 3

What is evaporation?

Answer 3

Evaporation is the changing of a liquid to a gas

Question 4

How do you separate sodium chloride from a sodium chloride and water solution?

Answer 4

1. Pour the salt solution into an evaporating basin
2. Heat the evaporating basin until most of the water is driven off
3. Place the evaporating basin over the beaker of boiling water
4. Sodium chloride alone should be left in the basin once the water has evaporated

Question 5

How do you purify rock salt using filtration and evaporation?

Answer 5

1. Crush small lumps of rock salt using a pestle and mortar
2. Place the rock salt in a beaker of warm water and stir to dissolve the salt
3. Let the mixture cool down and then filter into a conical flask using filter paper
4. Evaporate the salt solution in an evaporating basin over a beaker of boiling water

Question 6

Describe the distillation experiment

Answer 6

1. Pour sea water into the distillation flask and add anti bumping granules.
2. Turn on the water to the Liebig condenser which cools the inner tube
3. Heat the distillation flask and note that as steam passes through the Liebig condenser it is being culled and converted to a liquid again, distilled water

Question 7

What is paper chromatography used for?

Answer 7

To separate mixtures of substances in solution

Forensic science, art and food colouring

Question 8

How do you separate the dyes in a sample of ink using chromatography?

Answer 8

1. Cut a strip of chromatography paper and draw a line about 3 cm from the end of the paper to indicate the placement of the spot of ink.
2. Mark the spot of ink on the line and write the colour of the ink and solvent at the top of the paper.
3. Put the paper into a gas jar and pour 2 cm3 of solvent into the jar
4. When the solvent reaches the top of the paper, remove the paper and examine the chromatogram and the colours of the dyes in the ink