Classification of
Matter
Chp 15 Section 1
Composition of Matter
Classification of Matter
 Composition of Matter slides 3-34
 Properties of Matter slides 35-60
Composition of Matter
Chp 15 Section 1
Composition of Matter
 What are substances & mixtures
 How to identify elements & compounds
 The difference between solutions,
colloids, & suspensions
Composition of Matter
 Properties of materials can be used to
classify them into categories.
Composition of Matter
 Properties of materials can be used to
classify them into categories.
 Materials are either pure substances or a
mixture of substances.
Composition of Matter
 Properties of materials can be used to
classify them into categories.
 Materials are either pure substances or a
mixture of substances.
 A substance is a type of matter that is
always made of the same thing(s).
Composition of Matter
 Properties of materials can be used to
classify them into categories.
 Materials are either pure substances or a
mixture of substances.
 A substance is a type of matter that is
always made of the same thing(s).
 Substances are either an element or a
compound.
Composition of Matter
 A substance is an
element if all the
atoms in it are the
same.
 About 90 elements
are found on Earth;
another 20+ have
been made in
laboratories but are
unstable.
Composition of Matter
 A Compound is a substance with two or
more elements that are combined in a
fixed proportion.
Composition of Matter
 A Compound is a substance with two or
more elements that are combined in a
fixed proportion.
 Water is made of elements hydrogen &
oxygen in a 2:1 proportion.
Composition of Matter
 A Compound is a substance with two or
more elements that are combined in a
fixed proportion.
 Water is made of elements hydrogen &
oxygen in a 2:1 proportion.
 A molecule is the smallest particle of a
compound that has all the properties of
the compound.
Composition of Matter
 Chalk contains calcium, carbon, and
oxygen in a 1:1:3 ratio in each molecule.
Composition of Matter
 Chalk contains calcium, carbon, and
oxygen in a 1:1:3 ratio in each molecule.
 Elements combined in compounds often
look very different; for example, silvery
metallic sodium and the greenish-yellow
poisonous gas chlorine combine to make
sodium chloride or table salt (NaCl).
Composition of Matter
 A mixture is a material made up of two
or more substances that can be easily
separated.
Composition of Matter
 A mixture is a material made up of two
or more substances that can be easily
separated.
 In a heterogeneous mixture different
materials can be identified easily.
Composition of Matter
 A mixture is a material made up of two
or more substances that can be easily
separated.
 In a heterogeneous mixture different
materials can be identified easily.
 Granite, pizza and concrete are some
examples of heterogeneous mixtures.
Also, permanent press fabric of polyester
and cotton (microscope)…
Composition of Matter
 A homogeneous mixture contains two
or more substances blended evenly
throughout so that you can’t see different
substances in it.
Composition of Matter
 A homogeneous mixture contains two
or more substances blended evenly
throughout so that you can’t see different
substances in it.
 Examples include soft drinks in an
unopened bottle; however, it becomes
heterogeneous when you pour it and the
carbon dioxide escapes as bubbles
Composition of Matter
 Vinegar is another homogeneous
mixture which contains acetic acid mixed
with water.
Composition of Matter
 Vinegar is another homogeneous
mixture which contains acetic acid mixed
with water.
 Homogeneous mixtures such as soft
drinks and vinegar are also called
solutions.
Composition of Matter
 Vinegar is another homogeneous mixture
which contains acetic acid mixed with
water.
 Homogeneous mixtures such as soft
drinks & vinegar are also called solutions.
 A solution is a homogeneous mixture of
particles so small that they cannot be
seen with a microscope & will not settle to
the bottom of their container.
Composition of Matter
 Solutions stay constantly and evenly
mixed.
has mass
& takes up
space
Composition
definite
Two or more
kinds of
atoms
One kind of atom
composition
variable
Unevenly mixed
Evenly mixed; a
solution
Matter has
mass & takes up
space
Substance
Composition
definite
Compound
Two or more
kinds of
atoms
Element
One kind of atom
Mixture
composition
variable
Heterogeneous
Unevenly mixed
Homogeneous
Evenly mixed; a
solution
Composition of Matter
 A colloid is a special type mixture with
particles that are larger than those in
solutions, but not heavy enough to settle
to the bottom of their container.
Composition of Matter
 A colloid is a special type mixture with
particles that are larger than those in
solutions, but not heavy enough to settle
to the bottom of their container.
 Milk contains water, fat & proteins in
different proportions with large particles.
Composition of Matter
 A colloid is a special type mixture with
particles that are larger than those in
solutions, but not heavy enough to settle
to the bottom of their container.
 Milk contains water, fat & proteins in
different proportions with large particles.
 Paint is a liquid colloid; fog is a gas
colloid; smoke is solids suspended in air.
Do colloids and solutions look
the same?
 Fog looks white because its particles are
large enough to scatter light.
 Some shampoos & gelatins are colloids
called gels that look almost clear.
Do colloids and solutions look
the same?
 Fog looks white because its particles are
large enough to scatter light.
 Some shampoos & gelatins are colloids
called gels that look almost clear.
 You identify colloids by shining a beam
of light through it: you cannot see it in a
solution but you can see it in a colloid
because the large particles scatter light
(Tyndall effect).
What are suspensions?
 Some mixtures are neither solutions nor
colloids, for example, muddy pond water.
 A suspension is a heterogeneous
mixture containing a liquid in which you
can see particles settle.
 Rivers are natural examples of
suspension; moving quickly through
narrow channels they pick up soil which
then settles out when the water slows.
Comparing Solutions, Colloids,
& Suspensions
Description Solutions
Colloids
Suspensions
Settle upon No
standing?
No
Yes
Separate
using filter
paper?
Particle
size
No
No
yes
0.1-1nm
1-100 nm
>100 nm
Scatter
light?
No
Yes
yes
Matter
Give an
example of
each type
of matter
Substance
Compound
Element
Mixture
Heterogeneous
Homogeneous
Matter
anything
Give an
example of
each type
of matter.
Substance
wood
Mixture
pizza
Compound
water
Heterogeneous
granite
Element
Homogeneous
Carbon
vinegar
Properties of Matter
Chp 15 Section 2
Properties of Matter
 To identify substances using physical
properties
 Differences between physical and
chemical changes
 How to identify chemical changes
 The law of conservation of mass
Properties of Matter
 A physical property is a feature or
characteristic that describes an object or
substance such as color, shape, size,
density, melting point & boiling point.
Properties of Matter
 A physical property is a feature or
characteristic that describes an object or
substance such as color, shape, size,
density, melting point & boiling point.
 Some physical properties describe
behavior of material such as magnetic,
easily bent, malleable, flows easily,
viscous (thick liquid).
Properties of Matter
 Physical properties
can be used to
separate materials:



Sifting in gem mining
Magnetism to
separate metal
Seeds from fruit
Physical Change
 When a substance freezes, boils,
evaporates, or condenses, it undergoes
a physical change.
Physical Change
 When a substance freezes, boils,
evaporates, or condenses, it undergoes
a physical change.
 A physical change is a change in size,
shape or state of matter. Heat might be
added or removed but other properties
never change like density, specific heat,
boiling point and melting point.
What is distillation?
 Distillation is the process of separating
substances in a mixture by evaporating a
liquid & condensing its vapor.
What is distillation?
 Distillation is the process of separating
substances in a mixture by evaporating a liquid
& condensing its vapor.
The liquid is heated and
its vapor is cooled until it
condenses. A solid
material is left behind.
Salt water can be made
into drinking water this
way.
Distillation (continued)
 Liquids with different boiling points can
be distilled. Vapors of the liquid with the
lowest boiling point form first & are
collected. As the temperature increases
the second liquid boils, condenses & is
collected.
 Natural oils such as mint are distilled.
Chemical Properties &
Changes
 A chemical property is a characteristic
of a substance that indicates whether it
can undergo a change that results in a
new substance. When a substance
burns, there is a chemical change.
 Flammability is a chemical property
Chemical Properties &
Changes
 A chemical change results in a new
substance indicated by be smell, rust,
heat, light, or sound.
 Burning and rusting are chemical
changes because new substances are
formed.
Chemical Properties &
Changes
 You can separate
substances using a
chemical change.
 Example: cleaning
tarnish (silver sulfide)
off silver with another
chemical reaction
using warm water,
baking soda, and
aluminum foil.
Chemical Properties &
Changes
 Weathering shapes Earth’s surface
 Rocks split, rivers carve deep canyons,
sand dunes shift, and interesting
formations develop in caves.
 Are these changes physical or chemical?
Weathering
Physical Weathering
Weathering
Physical Weathering
Weathering
Chemical Weathering
Chemical weathering
 The most common types of chemical
weathering are oxidation, hydrolysis and
carbonation.
Chemical weathering
 The most common types of chemical
weathering are oxidation, hydrolysis and
carbonation.
 Limestone which is mostly calcium
carbonate dissolves in slightly acidic
water to create caves and rock
formations.
Law of Conservation of Mass
 The mass of all substances that are
present before a chemical change
equals the mass of all substances that
remain after the change.
Law of Conservation of Mass
 The mass of all substances that are
present before a chemical change
equals the mass of all substances that
remain after the change.
 When a log burns, you see smoke and
light, feel heat, and note a change in
appearance indicating a chemical
change is taking place.
Calculate
 If a 2-kg log is burned, what is the mass
of the ash, smoke, and carbon dioxide
produced by the chemical change?
Calculate
 If a 2-kg log is burned, what is the mass
of the ash, smoke, and carbon dioxide
produced by the chemical change?
 According to the Law of Conservation of
Mass, the mass of everything left would
be 2-kg.