CLASS COPY – Do NOT write on this Paper – Do NOT remove this paper from the class without permission!
Activity 1c: Density of Earth Materials
Learning Target:
1c)
LAB:
Unit D: The Dynamic Earth
collect and analyze data about the density of Earth materials (DOK2)
Density of Earth Materials
*** Make a new entry in your science notebook. Be sure to include title, date, and purpose. As you work through
this lab, write notes in your science notebook, using the numbers provided to track your work. ***************
Purpose:
Collect and analyze data about the density of common materials – both liquids and solids.
Procedure:
Part A: Effect of Density of liquids on the Position of Materials
1. Locate your materials: Notice how they are set up – this is how they should be at the end of class.
 30 mL each of water, pancake syrup, and shampoo
 medicine cups (30 mL capacity)
 plastic pipettes
PREDICT:
2. Suppose you were to carefully pour a small volume of each liquid into one graduated cylinder or clear tube.
A. Predict what you think will happen.
B. Sketch your prediction.
C. Explain the reason for your prediction.
OBSERVE:
3. One at a time, carefully pour 10 mL of each liquid into the same empty medicine cup cylinder.
A. Describe your observations.
B. Does the order in which you pour the liquids make a difference in what you observe?
EXPLAIN:
4. Discuss the following questions with your team. Record your ‘best thinking’ after the discussion.
A. Did your observations support your prediction?
B.
Explain why or why not (include evidence from your lab so far)?
C. What do you suppose determines whether a liquid will sink or float?
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Most people recognize that DENSITY plays a role in the position of materials. What is density and how can it
explain your observations? Record the information in the box below into your science notebook.
FYI – Density is mass per unit volume.
This can be written as:
D = m/V
Where:
D = density (reported in g/mL or g/cm3)
m = mass (measured in g)
V = volume (measured in mL or cm3)
PREDICT:
5. Predict which of the three liquids has the greatest density and which has the smallest density.
Most dense ___________________ Medium dense __________________ Least dense ______________
6. Explain why you think this is the order of their density.
OBSERVE:
7. Develop a method to determine the density of each of the three liquids using a graduated cylinder, 10 mL of
each liquid, and a balance. Remember the formula for density.
A. Write your procedure using a labeled diagram.
B. Make a data table to record your measurements and calculations for each liquid.
C. After your teacher has approved your procedure, determine the density of each liquid.
D. Write it in the data table you made.
E. Clean up your lab station.
EXPLAIN: Discuss the following questions with your team. Record your ‘best thinking’ after the discussion.
1. Compare the results of your calculations with your observations in Step 3.
A. Describe how the densities you calculated explain what you observed.
B. If layers of materials of different density within the Earth behave like layers of liquids of different
densities, what would you predict about the positions of the rock layers of different densities in the
Earth?
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CLASS COPY – Do NOT write on this Paper – Do NOT remove this paper from the class without permission!
Part B: Density of Earth Materials
1. Locate your materials:
Notice how they are set up – this is how they should be at the end of class.
a. small samples of Earth materials, including basalt (black), granite(pink spotted), quartz (clear/pink glassy),
iron ore (magnetite or hematite)(black or rusty), and sandstone (grainy reddish brown)
b. graduated cylinder(s)
c. overflow can
d. balance (shared)
PREDICT:
2. Without using any scientific equipment, predict the relative density of your rock samples.
Which sample seems to be the least dense? most dense? Make a rank listing of the samples.
Least dense ______________, __________________, _________________, ______________,
_______________ most dense
OBSERVE:
3.
a.
b.
c.
d.
Develop a method to determine the density of each rock sample using water, a graduated
cylinder, an overflow can, and a balance.
Record your procedure using a labeled diagram.
Make a data table to record your measurements and calculations for each liquid.
? Will you do multiple trials? Why or Why Not?
After your teacher has approved your procedure, determine the density of each sample.
Record your findings in your data table or a separate results table.
EXPLAIN:
11. Discuss the following questions with your team. Record your ‘best thinking’ after the discussion.
a. Did your observations support your prediction? Why or why not?
b. How do the observations and calculations you made in this investigations relate to what is happening
inside the Earth? Make a claim about the relationship between density of earth materials and placement
of those same earth materials and support it with evidence from this investigation. Add a diagram to
accompany your claim, noting where density is greatest and smallest within the Earth.
You may use ONE of the following sentence starters:


Earth materials that are located _________ are (less, more) dense than Earth materials located ________
. I know this because _________
As you move down through the Earth, the density of the materials that make up Earth’s layers gradually
(decreases, increases) because _______
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