Chapter 15
Properties of Matter
Classifying Matter
• Matter is a term used to describe any
material that has mass and takes up space.
• Matter can be classified as either a mixture
or a substance.
– Substances can either be elements or
compounds.
• Matter has different characteristics such
as: boiling and melting temperatures,
hardness, density, elasticity
What is A Mixture?
• A mixture is made out of more than one
kind of matter
• An example is soda, because it can be
separated into carbonated water, corn
syrup, caramel color, phosphoric acid,
natural flavors and caffeine
• There are two types of mixtures,
heterogeneous and homogenous
Types of Mixtures
• A Homogeneous mixture is the same throughout. All
samples of this type of mixture would be the same.
Examples: soda, salt water, brass (a mixture of copper
and zinc)
– A solution is a type of homogeneous mixture with
particles that are so small they cannot be seen with a
microscope. Made with water (solvent) and a solute such
as salt
– An alloy is a solid mixture, such as brass. You must melt
the metals to mix them
• A Heterogeneous mixture has different parts that are
visible in the mixture. Examples: Chicken noodle
soup, M&M’s, Chex mix
• Sometimes heterogeneous mixtures are hard to see (a
cotton polyester blend shirt for example)
Colloids
• A colloid is a mixture with larger particles
than in a solution, but not heavy enough
to settle out. (ex.- milk, fog)
• Detected by the Tyndall Effect, in a colloid
light beams are scattered and you can see
the beam easily
Suspensions
• Heterogeneous mixture in which large
particles settle
• Muddy pond water
• They do scatter light like colloids, but the
particles are much larger and some
actually settle out of solution
Mixtures vs. Substances
• Mixtures can be separated into different types of
matter by physical means
• Substances cannot be separated easily
• Substances include:
– Elements- The smallest sample of matter, contains
only one type of atom (silver, oxygen)
– Compounds: Two or more elements joined together
chemically and cannot be separated by physical
means ( water, salt, sugar)
Properties of Matter
• Physical Properties – characteristics of a
material which can be observed without
changing the identity of the material.
(size, shape, color)
• Chemical Properties – characteristics of a
substance indicating that it can change
chemically. (flammability)
Properties of Solids
Hardness
• Resistance to
scratching
• Talc is the softest –
baby powder
• Diamond is the
hardest
Elasticity
• Ability to stretch
and return to the
original form
• Gives the ability to
bounce and
withstand an
impact
Brittleness
• Tendency to shatter
on impact - glass
• Safety glass is coated
with cellulose nitrate
• Enhanced protective
glass – two pieces of
glass with Saflex in
between – used in
cars and as a sound
barrier
Malleability
• Solids ability to
be pounded into
sheets
• Aluminum foil
Ductility
• Ability to be pulled
into thin wire
• Gold and silver
Tensile strength
• A measure of how much
tension or pulling that a
material can withstand
• Strength of rope, fiber,
and cables
• Kevlar - is constructed of
para-aramid fibers which
are five times stronger
than the same weight of
steel, while being
lightweight, flexible and
comfortable. It is also
very heat resistant and
decomposes above 400 °C
without melting.
More Properties of Solids
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Boiling point
Melting point
Color
Conductivity
Mass
Odor
Shape
State of Matter
Measuring Matter
• Mass- amount of matter
in an object
• Measured in grams or
Kg
• Use a triple beam or
electronic balance to
determine
• You can get the mass of
a liquid by massing it
in the container and
subtracting the mass of
the container
Volume
• Volume- Amount of
space something
takes up
• Volume of a liquiduse a graduated
cylinder
• Volume of a solidlxwxh
• Displacement
Displacement
• Use the displacement
of liquid in a
graduated cylinder to
determine the volume
of an object
• Useful for small,
irregularly shaped
objects
How to measure volume using
displacement
• Pour an even volume of water into a
graduated cylinder
• Read the volume
• Drop the object in the water
• Read the volume
• Subtract to get the volume of the object
Density
• Relationship between
mass and volume
• Tells us how tightly the
atoms or molecules in a
material are packed
together
• Higher density – atoms
are closer together
• Lower density- atoms
farther apart
• Size and shape do not
effect density
M
D
V
Density
• You must have the
volume and the mass
to calculate density.
• A material’s density is
a physical property
and stays the same for
that particular
material, but can
vary due to state of
matter and
temperature
Units:
Mass in kg or g
Volume in cm3 or mL
Density in g/cm3,
g/mL, kg/cm3,
kg/mL
• Most of the time will
be the first two
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•
•
Density and Temperature
• As the temperature increases, density
decreases
• A solid that is warm will have a slightly
lower density than a solid that is cold
• The same is true for gases and liquids
Density of liquids
• In liquids the volume increases because
the molecules are moving more quickly
• The volume increases so density decreases
• Liquid silver is less dense than solid silver
• Water is an exception– ice floats on water
• Solid water is less dense than liquid– this
is important in nature
Density Lab
• While vacationing
in California, you
find a large chunk
of metal that
appears to be gold.
How can you make
sure you struck it
rich without letting
anyone else know
about the find?
Lucky you, you remember that
all materials have a density that
is specific to themselves.
• So the first thing
you do is look
up the density
of gold.
So then you measure the mass
of your sample.
So then you measure the
volume of your sample.
• Unfortunately the
sample is an odd
shape, but you
remember from
your physical
science class how
to measure
volume by the
displacement
method.
Do you have Gold?
YES!!!!!!
Now, let’s see how rich you are.
Gold is currently selling at
$1,664.00 / ounce
1 ounce = 28.35 grams