Chemistry 11
Unit 3 - Matter
Experiment on Methods of
Physical Separation of
Mixtures
Name____________________________________
Name____________________________________
Purpose: To examine several methods used to separate mixtures into pure substances.
Station 1 – Chromatography
Purpose: To separate colors from food colouring using paper chromatography
Materials:
Yellow, Red, Blue and Green Food colouring
Chromatography paper
2x Large test tube in 2 - 250mL flasks
Procedure
1. Set up 2 of the apparatus shown in the figure by: Cut 2 pieces of chromatography paper as shown
below.
2. Use a tooth pick to place a VERY SMALL DROP of food coloring on the line as shown above.
Everyone will test the colour green AND another colour either red, blue or
yellow.
3. Place enough water in a large test tube so the when the paper is inserted, the level of the water
will be above the bottom of the paper and below the food colouring mark.
4. Place the paper in the test tube so that it’s bottom edge (but not the sample
mark) is immersed in water. Do not allow the flat surface of the paper to
touch the sides of the test tube. Place the test tube in a 250 mL flask
Allow the water to be soaked up into the paper for 15 minutes.
5. Identify 2 fronts as they move up the paper. One is the solvent,
the water, the other front is the solute, the food colouring.
6. After 15 minutes remove the paper from the test tube and draw a line
across the solvent front and the solute front, using a PENCIL.
Measure d1 and d2 shown as on the diagram.
7. Let your papers dry so you can staple or glue it into your lab report.
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Chemistry 11
Unit 3 - Matter
Station 2 - Filtration
1. There are two bottles; one labeled SOLUTION and one labeled SUSPENSION.
Fold two pieces of filter paper and place one in each of the two funnels.
To fold the filter paper: fold the round filter paper in half, then in half again. Then
open the paper up from the center to create a cone shape.
2. Place the filter paper in each funnel over a clean beaker.
3. Pour a small amount of the NaCl solution into one funnel and a small
amount of the CaCO3 suspension into the other funnel.
4. Observe the filter papers and the beakers below the funnel.
5. Answer the questions for Station 1 below, then discard the filter papers in the
garbage clean out each beaker. Move onto another station.
Station 3 -Distillation
Go to the data and observation section.
Station 4 - Gravity Separation
Procedure
1. Obtain two small test tubes labeled “A” and “B”
2. To test tube “A”, fill it to the mark with salt water
solution. Place it in the centrifuge.
3. Shake the bottle of “Suspension”, then add the
suspension to test tube “B” up to the mark. Place test
tube “B” in the centrifuge DIRECTLY ACROSS FROM test tube “A”.
4. Switch on the centrifuge (make sure you keep hands, clothes etc. away from the
top of the machine!) Let it come up to speed and spin for about 30 seconds.
5. Switch off the centrifuge and let it slow down. When it is going quite slowly,
stop it and remove the test tubes. Observe them and note the results.
6. Use a brush to clean out test tube “B”, rinse both test tubes and put them back
in the rack.
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Chemistry 11
Unit 3 - Matter
Data and Observations
Name - _____________________________
Date - _______________________
Station 1 – Chromatograghy
Table 1 – Food Colouring Chromatography
Colour Tested
d1
d2
The Rf value is used to quantify the movement of the materials along the plate. Rf is
equal to the distance traveled by the substance divided by the distance traveled by
the solvent.
Rf value = d1 / d2
Table 2 – Green Food Colouring
Colours
d1
Rf
d2
Green
Questions
1. Is the green food colouring a pure substance or a mixture? _________________________
2. What is the solvent in this experiment? ________________________________.
3. Chromatography uses has 2 phases: a stationary phase and a mobile phase.
a. The paper is the __________________ phase and the water is the
____________________ phase.
Colour
Rf value
Red #2
0.81
Red #3
0.41
Red #4
0.62
Blue #1
1.0
Blue #2
0.79
Yellow #5
0.95
Yellow #6
0.77
4. Compare your results to the table above, what colours are present in the food colouring you
selected.
Give a tentative explanation (hypothesis) of how the colours in the green food colouring are
separated.
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Chemistry 11
Unit 3 - Matter
Station 2 – Filtration
1. Does filtration separate a NaCl solution into its components? ____________________
2. Considering the sizes of particles in a solution, give a possible reason for your
answer to question 1.
3. Does filtration separate a CaCO3 suspension into its components? __________________
4. Considering the sizes of particles in a suspension, give a possible reason for
your answer to question 3.
5. In filtration, the material left in the filter paper is called the _________________
6. The material which goes through the filter paper in called the _______________
Station 3 - Distillation
1. In the space below label all the parts on the diagram:
Temp here = _____°C
Aprox. Temp here
= ___°C - ___°C
The Stuff that
gets collect in
here is called
the
___________
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Chemistry 11
Unit 3 - Matter
2. Touch the outside of the condenser. Is it hot or cool? _______________
3. Observe the liquid in the receiving vessel. Is it the same colour as the material in the
distillation flask? ______________
4. What is the temperature at the neck of the boiling flask? (from the thermometer) ______


What is the boiling point of water? _____________
Look up the boiling point of ethanol? _____________
5. The impure liquid in the distillation flask is a solution (a homogeneous mixture) of
Blue water and ethanol. The _________________________ is boiling but the
_________________________________ is not. The blue water and the ethanol
must have different _____________________ ______________________.
6. What does the condenser have circulating in the “outer jacket”? _______________
Where does it come from? _______________________________
7. What is happening in the glass tube on the inside of the condenser? __________
_______________________________________________________________
8. In distillation, the material ending up the receiving flask is called the _________
If the original material was simply heated without having the condenser, what would
happen to the liquid which boiled? ______________________________________
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Chemistry 11
Unit 3 - Matter
Station 4 - Gravity Separation
1. Is gravity separation able to separate the components of a solution? ____________
2. Is gravity separation able to separate the components of a suspension? __________
2. Solution B was a mixture of CaCl2(aq) and Na2CO3 (aq). Use the solubility table to determine
the products of this reaction.
3. What was the white solid of the suspension? _________________
4. After the test tube was in the centrifuge.
a. What compound was on the bottom of the test tube? ______________
b. What was in the top part of the test tube. _______________
5. Suggest a common suspension this method could separate. ______________________
Lab Questions
1. Name one heterogeneous mixture present in this lab. ____________________
2. Name one homogeneous mixture present in this lab. ____________________
3. Name one pure substance present in this lab. ____________________
4. List 1 piece of Qualitative Data collected in this lab. _______________________________
5. List 1 piece of Quantitative Data collected in this lab. ______________________________
6. Write a procedure to describe how you would separate a mixture of Salt
(NaCl), Sand,
Small plastic beads and Glass Marbles. You want to keep all components!
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