Science 7
Notes 6
Density
Define Density.
Determine if an
object will sink or
float based on its
density.
What is Density? The mass per unit volume of a substance
 It tells you much of the substance’s mass fits in a space.
What is the formula for Density?
What is the
formula to solve
for density?
D= m
v
Does it float or sink?
 Water has a density equal to about 1g/cm3
Why will objects
float in water?
Why will objects
sink in water?
 Objects that are less dense that water will float
 Objects that are more dense than water will sink
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Science 7
Notes 6
Generally, how
does the density
of a gas compare
to a liquid?
Generally, how
does the density
of a liquid
compare to a
solid?
Generally, if you
place a solid into
a liquid, what
will you see
based on density?
Water is Strange
Solid water is less dense than liquid water.
What is strange
about the density
water?
So, ice and anything else with a density less than 1g/cm3 will float
in water.
Practice:
Practice:
Calculate the
density of an item
with a mass of
4.0 g and a
volume of 4 mL
The following list contains information for four liquids and two
solid objects. Complete the density table on the next page by
determining the density of each object.
 a yellow liquid with a mass of 2.8 g and a volume of 2 mL
Practice:
Calculate the
density of an item
with a mass of
8.0 g and a
volume of .5 mL
 a green liquid with a mass of 6 g and a volume of 3 mL
 a red liquid with a mass of 1.8 g and a volume of 2 mL
 an orange liquid with a mass of 1.3 g and a volume of 1 mL
 a blue cube with a mass of .8 g and a volume of 2 cm3
 a pink star with a mass of 2.4 g and a volume of 0.8 cm3
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Science 7
How do you
know if a solid
has a greater
density than a
liquid?
Notes 6
Color or Label the the liquid layers in the container on the
right. Add the two solid objects at the appropriate
locations.
1. Which liquid is the most dense?
___________________
2. Which liquid is the least dense?
___________________
What do you
know about an
object’s density if
it floats in water?
3. Which object will settle to the bottom?
______________
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