Density
Jose Santos & Heather Wynn
Peer Presentation – EMPACTS Project, Spring 2015
What is Density?

Density is defined as
the ratio of an object's
mass to its volume.
What is density exactly?
Density will increase if the mass
Increases within a specific unchanging
Volume of space.
If liquids of different densities are
Added to the same solution, the
Liquids will separate by density.
Some liquids or objects will float and
Others will sink.
The solid objects and
liquids will
Separate based on
the density
Of each substance,
liquid, solid or
Gas.
History of Density

It is the story of a Greek mathematician named Archimedes who lived around
250 B.C. The King of Syracuse, where Archimedes lived, thought that he was
being cheated by the metal craftsman who made his golden crown. The king
called Archimedes to him and gave him the task of finding out whether the
craftsman had replaced some of the gold in the king's crown with silver. Silver
was worth less money than gold, and it also was an insult to the king to be
wearing a crown that was not pure gold.
But…
…..The king gave Archimedes some rules.
Archimedes could not damage the crown in any
way. He could not melt down the crown to see
if it was made of other metals. He could not
scratch the crown to see if there was silver
underneath the golden outside.
Archimedes thought about the problem while
taking a bath. As he entered the bathing pool,
he noticed that water spilled over the sides of
the pool. He realized that the amount of water
that spilled was equal in volume to the space
that his body occupied.
This fact suddenly provided him with a method
for finding out if the king's crown was made of
pure gold.
Why is Density Important?

Knowing the mass of an object relative to
its physical dimensions becomes critical in a
wide variety of applications in the natural
sciences, as well as technological fields. It
allows you to discern between different
materials and substances. You can identify
what transport and handling requirements
there may be, and project how those
substances will react to changes in
temperature and pressure. To some degree,
you can also predict their behavior when
interacting with other substances.

Example: A child’s toy—the gas-filled balloon. Helium
is considerably less dense than regular environmental
air. When a balloon is filled with helium, its volume
increases, but because the helium contained within
the walls of the balloon is lighter than the surrounding
air, the balloon floats.
How To Determine Density

To determine the density of a
regularly shaped solid, first
measure the object's mass—that is,
weigh the object. Next, measure
one or more of the object's
dimensions and calculate its
volume from a mathematical
formula for objects of that shape.
Then divide the mass by the
volume.
Facts About Density

Earth scientists use density measurements to identify minerals and other
solids.

Chemists measure the density of a solution to determine the concentration of
a substance in that solution. They also calculate the relative molecular mass
of a gas from its density.

Density measurements are used when weight and weight distribution are
important. This may include the construction of ships, buildings, airplanes
and other modes of transportation. Density measurements are also useful
when determining how much force is required to move a liquid through piping
or tubing. Density also comes into play when packaging engineers design
squirt bottles for things such as ketchup and mustard.

)Density is commonly expressed in grams per milliliter or pounds per cubic
foot
Classroom Demonstration using Super
Saturated Sugar Water – Density column

When sugar is added to water which is very hot – boiled, the
solubility – how easily the sugar goes into solution – will increase.

Stirring also will increase the ability of a solvent to dissolve a
solute.
Sugar Water Density Tower
In theory, the more mass/unit
volume each solution has
The greater the density of the
liquid.
So differing densities of sugar
solutions with dyes should
Separate according to their
different densities.
This was our first attempt…
Works Cited

http://blog.drtubs.ca/wp-content/uploads/2013/10/Archimedes-in-tub-cartoon.jpg

http://edhelper.com/ReadingComprehension_37_182.html

http://www.ehow.com/about_5484217_importance-density.html

http://www.green-planet-solar-energy.com/images/formula-for-density.gif

http://www.life123.com/parenting/education/physics/why-density-important.shtml

http://thumbs.dreamstime.com/z/children-holding-balloon-vector-illustration-balloons36210684.jpg

https://answers.yahoo.com/question/index?qid=20091027180738AAziP68

http://3.bp.blogspot.com/2KPuZYzPDZg/UOxgdPhqxcI/AAAAAAAAAgQ/dOq5LBQGoaI/s1600/fun-facts.jpg

http://www.merriam-webster.com/dictionary/specific%20gravity

http://ts4.mm.bing.net/th?id=JN.JUitluCKkhXxvGq0qmb4zA&pid=15.1&H=160&W=160

http://ts3.mm.bing.net/th?id=JN.TrNbaxo%2bb6ggTe7784MrmQ&pid=15.1&H=241&W=160

http://ts3.mm.bing.net/th?id=JN.Itz%2bNFgT8JNQAAr0ARrX0Q&pid=15.1&H=146&W=160

http://whs.wsd.wednet.edu/faculty/busse/mathhomepage/busseclasses/apphysics/studygui
des/chapter9/graphics/Fig-09-19.gif