Making a Density Column (Topic 2)
Your job is to determine the order of densities of certain liquids from the most dense to the least
dense. You will be able to do this based on how the liquids interact. At the end of the activity you
will be able to verify your observations by calculating the densities of each substance.
Materials:
 Detergent (choose a color that will allow you to tell it apart, e.g. blue)
 Water
 Syrup
 Vegetable oil
 Clear plastic cups
 Graduated cylinder
 Balance
1. Label 4 cups from 1 – 4, and using a balance measure the mass of each cup. Record your
observations in Table 1.
Table 1
Cup 1
Cup 2
Cup 3
Cup 4
Mass (g)
2. Use a graduated cylinder and measure 30 milliliters of each substance provided and place in
the separate plastic cups. Make sure to clean the graduated cylinder before pouring the new
substance. Do the masses of each substance appear to be the same? Explain:
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
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3. Which substance appears to be heavier (has the highest mass)? ______________________
_________________________________________________________________________
_________________________________________________________________________
4. Which substance appears to be the least heavy (has the lowest mass)? ________________
_________________________________________________________________________
_________________________________________________________________________
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Making a Density Column (Topic 2)
5. Measure the mass of each cup containing the separate substances. Record your
observations in Table 2.
Table 2
Mass (g)
Cup 1 + Detergent
_________g
Cup 2 + Syrup
_________g
Cup 3 + Vegetable oil
_________g
Cup 4 + Water
_________g
6. Calculate the mass of each substance by subtracting the mass of each cup recorded in table
1. Record the mass of only the substance in Table 3. Remember that each cup has 30 ml of
each substance.
Table 3
Mass (g)
Volume (ml)
Detergent
_________g
30 ml
Syrup
_________g
30 ml
Vegetable oil
_________g
30 ml
Water
_________g
30 ml
7. If all the substances are poured into the plastic cup one at a time, what do you think will
happen? __________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
8. Which substance do you think will be on the very bottom? ___________________________
9. Which substance do you think will be on the very top? ______________________________
10. Which substance do you think is the most dense? (remember you measured the same
amount of volume for each) ___________________________________________________
_________________________________________________________________________
11. Which substance do you think is the least dense? __________________________________
_________________________________________________________________________
2
Making a Density Column (Topic 2)
12. In the picture below, write your predictions of the order in which the layers will stack.
Prediction
Observation
______________
_____________
______________
_____________
______________
_____________
______________
_____________
13. Pour all the substances into one cup, one at a time. No spilling! This is called a Density
Column. Wait a few minutes until the liquids settle and on the right side of the picture, label
the observed layers in the column.
14. List the liquids in order from the most dense to the least dense:
Name of Substance
Least dense
Most dense
15. Is there a relation between the substance location and its density? ____________________
_________________________________________________________________________
16. Which liquid(s) have a density greater than water?
_________________________________________________________________________
17. Which liquid(s) have a density less than water?
_________________________________________________________________________
3
Making a Density Column (Topic 2)
Now, to verify your observations, you can perform a density calculation by dividing the volume of
each substance (Step 2) from the measured mass of each substance (Table 3). Record your
results below in Table 4.
Table 4
Volume
(ml)
Substance
Mass
(g)
Density of substance
(g/ml)
Detergent
________ g
30 ml
_________ g/ml
Syrup
________ g
30 ml
_________ g/ml
Vegetable oil
________ g
30 ml
_________ g/ml
Water
________ g
30 ml
_________ g/ml
Examine the results and compare to your predictions and observations in step 12. What can you
explain? _____________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
If you had to measure 1 L of water, do you think the volume it would occupy would be greater,
smaller, or the same that you measured above for the 30 milliliters? ______________________
_______________________________________________________________________
What will be the density of the 1 kg of water? Will it be greater, smaller, or the same as the
density you measured above? Why? _______________________________________________
_______________________________________________________________________
_______________________________________________________________________
4
Making a Density Column (Topic 2)
Teacher Notes:
Density is an important physical property of matter. Substances can be classified by their
density. The density of a substance is always the same, no matter how much of it you have.
One gram of gold has the same density as 100 kg of gold. The amount of gold does not change
the density of gold. The substance is still gold.
Imagine a wall made up of gold bricks. Each brick is solid gold. Will the mass be great? Will the
volume be great? If the entire wall is placed in a huge tub of water, would it sink or float?
What about if we compare to one brick of gold? Is the mass larger or smaller than the wall? Is
the volume larger or smaller? If we place it into the tub of water, will it sink?
How about a tiny gold ring? The gold always sinks because the density of gold is always greater
than the density of water, even if it is just a little piece of gold.
Substance
Approximate Densities
(g/ml)
Detergent
1.05 g/ml
Syrup
1.36 g/ml
Vegetable oil
0.9 g/ml
Water
1.0 g/ml
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Making A Density Column