Objective 1
 Sorting: The process that separates particles based on
differences in density and/or particle size.
 Mixture: A combination or blend of two or more
substances that have not chemically combined. Each
substance maintains its own identity.
 Particle: A small piece of something. Typically used to
represent a small part of matter.
 The formula for calculating density is Density = Mass/ Volume
 Water has a density of 1 g/mL= 1 g/cm3
 Material that has a density greater than 1g/mL will sink.
 Material that has a density less than 1g/mL will float.
 Example rock sinks, wood floats in water
Element
Hydrogen (H)
 1) If you have a 4 cm3 sample of rock salt with
Helium (He)
mass of 10 grams, what is the density?
Aluminum (Al)
 2) You have a 10 cm3 sample of water with a
Zinc (Zn)
mass of 10 grams what is the density?
Tin (Sn)
 3) You have an unknown metal with a volume of Iron (Fe)
Nickel (Ni)
4 cm3 and a mass of 42.0 grams. Compared to
the chart, what is this metal most likely to be? Copper (Cu)
Silver (Ag)
 4) Find the density of an unknown liquid in a
beaker. The empty beaker's mass is 165 grams. Lead (Pb)
With the unknown liquid inside the beaker, the Mercury (Hg)
total mass is 309 grams. The volume of the
Gold (Au)
unknown liquid is 125mL. Is the liquid pure
Platinum (Pt)
water? Explain your answer.
Density (g/cm3)
.00009
.00018
2.7
7.13
7.31
7.87
8.9
8.96
10.5
11.35
11.55
19.32
21.45
The earth’s materials are naturally sorted according
to density AND particle size.
More dense items settle on the bottom.
Items with larger particle size settle on the bottom,
then smaller particles fill in the empty spaces
between the more dense objects.
Larger, more dense materials are found at the
beginning of a stream bed and finer, less dense
particles are found at the end of a streambed.
On a beach, more dense particles stay at the bottom
of ocean and sand on beach all has the same density.
Sort silt, gravel, pebbles and rocks and place them
in a jar with water.
Shake it up and let the materials settle.
How do they settle, and why do they settle that
way?
Objective 2
 Density: comparison of the mass and volume of an object.
Calculated as mass/volume.
 Atmosphere: various layers of air that surround the earth.
The densest layers are closer to the earth, the least dense
layers are further away from the earth.
 Crust: solid outer layer of Earth where life is found. This
is the thinnest Earth layer.
 Inner core: centermost layer of Earth. Solid metal, is the
hottest and most dense.
 Outer core: Liquid layer of Earth found near the center.
Found between the mantle and inner core. Made of
metals.
 Mantle: semi-solid layer of Earth that takes up the most
volume. Found directly below the crust.
The earth is layered because of density. The order
from most dense to least: Inner Core – Outer Core –
Mantle – Crust – Water – Atmosphere
http://www.learner.org/interactives/dynamicearth
/structure.html
Most dense to least dense from the Earth’s Core to
the Atmosphere. The denser the material the
deeper it sinks to the center of the earth.
Composition
Atmosphere
Approximate
Density
0.0013 g/mL
Water
1.00 g/mL
Liquid
Crust
2.7 - 3.0 g/mL
Hard and rocky
Mantle
3.3 - 5.7 g/mL
Soft and flexible
Outer Core
9.0 - 12.0 g/mL
Liquid nickel and iron
Inner Core
12.7 - 13.0 g/mL
Solid nickel and iron
Layer
Gases
Many models of Earth exaggerate
the size of surface features such
as mountains. If Earth were
shrunk to globe size, it would be
very smooth.