Earth Essential Questions
Unit Story: You should be able to tell the following by the end of the unit.
All matter is made up of atoms that are far too small to see. Atoms are always in motion
and the more energy they contain the faster they move. Atoms combine to form molecules.
Matter is made up of atoms and molecules that have measurable mass, volume, and
density. Density is a measure of the compactness of matter. It is the amount of matter
(mass) per unit of volume. Density determines the way materials in a mixture are sorted.
Sorting according to density results in the layering and structure of Earth’s atmosphere,
water, crust, and interior. Models are used to describe the structure of Earth.
Directions: The following essential question journal gives you the opportunity to reflect on and review what
you learn. It is made of only key points and questions. Each essential question will ask to recall something you
should know or ask you to demonstrate how to do something.
Students will understand the relationship between properties of matter and Earth’s structure.
Part 1: Examine the effects of density and particle size on the behavior of materials in mixtures.
A. You are given an unknown object. You find its mass to be 28g. You find its volume to be 10 mL.
Using the chart below, determine which layer of the Earth the object would belong to based on its
density.
The object would belong to the ____________________ layer.
Sample Earth density chart:
Layer
Water
Crust
Mantle
Outer Core
Inner Core
Approximate Density
1.0 g/mL
2.7 – 3.0 g/mL
3.3 – 5.7 g/mL
9.0-12.0 g/mL
12.7 – 13.0 g/mL
B. Calculate the density of earth materials (e.g., rocks, water, air).
There is nothing "tricky" about this data. In fact, if you wish, you may use a calculator to
assist you!
Mass in
grams
Volume in cubic
centimeters
Substance
1. Gold
2. Oxygen
3. Water
4. Helium
5. Mercury
193.2g
1.33g
10.0g
1.663g
67.75g
10 cm3
100 cm3
10 cm3
10,000 cm3
5 cm3
6. Copper
224g
25 cm3
Density in grams/cubic
centimeters
C. Below are pictures of six different-sized particles. Imagine that you can put them in a large
graduated cylinder filled with water and then shake it vigorously. The particles are labeled A, B, C,
D, E and F. Look closely at each and determine the order you would arrange them in based on how
they would settle out ... from bottom to top. Simply number each with 1 being the bottom and 6
being the top.
D. Describe the sorting of materials that can be observed in a streambed, road cut, and beach to the
density and particle size of those materials.
1. Stream Bed
2. Road Cut
3. Beach
Part 2: Analyze how density affects Earth's structure.
A and B. Now that you have learned about the four basic layers of the Earth let’s put your
knowledge to the test. The table below has each layer labeled. You need to fill in the missing
information for each. (You may use your row for this Question)
Earth’s Layers
Crust
Mantle
Outer Core
Inner Core
Soil, Water,
Rocks (above
crust)
Atmosphere
Temperature in
Celsius
Depth Range
(From
Beginning to
End)
What is the
Layer Made of?
Average
Density of
Layer
1C. Which answer shows the following items in order from the highest density to the lowest density?
a. water, atmosphere, core, crust
b. atmosphere, crust, core, water
c. crust, water, atmosphere, core
d. core, crust, water, atmosphere
2C. Why is water located above the crust but below the air?
a. The density of water is higher than air and higher than the crust
b. The density of water is lower than air and higher than the crust.
c. The density of water is higher than air and lower than the crust.
d. The density of water is lower than air and lower than the crust.
1D. Given the model of the Earth shown below, write a short paragraph explaining whether or not
this is a good model of the Earth or a poor model of the Earth. Cite reasons that will help to defend
your answer.
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
_____________________________________________________
2D. Circle which of the two models below shows the Earth’s outside shape more correctly? Explain your
answer.
A.
B.
A.
B.
3D. Circle which model above is most correct in describing the main layers of the Earth. Explain your answer.
4D. In the past, many people thought that Earth was hollow. Why is this model of Earth not
accepted now?
A. Today scientists have collected data that support a layered model of Earth.
B. The current layered model of Earth’s structure has now been proven.
C. Models of Earth’s structure only last a certain amount of time and then they are replaced.
D. Scientists have now taken samples of Earth’s core and know the old model was wrong.
Part 3 Misc.:
A. What was your favorite part of this unit?