Properties of Matter
Chapter 6
6.1 Matter
Objectives
• Define matter and describe its
major properties.
• Explain how the arrangement
of particles in a substance may
determine its properties.
• Classify kinds of matter based
on their properties.
• Make a model illustrating the
particle model of matter
Matter
• Imagine you are an astronaut
approaching the earth from space.
• If you land on a beach, you see sand and
waves.
• Looking closer, you see even the
individual grains of sand that make up
the beach.
• Do you think the grains of sand are
made of things that are still smaller?
Particle Model of Matter
• Grains of sand and everything
else you see, hear, smell, touch,
and taste are made of matter.
• Matter is anything that has
mass and takes up space.
• Matter exists in many shapes,
colors, textures, and forms.
Water, rocks, living things, and
• stars are all made of matter.
Matter
• All forms of matter are made up of tiny
particles that are in constant motion.
• This idea is known as the particle model
of matter.
• Matter contains huge numbers of
particles that vary in their size, shape,
arrangement, motion, and individual
properties.
Properties of Matter
• Matter has characteristics
that help to identify it.
• These characteristics are
known as properties.
• Some properties such as mass,
volume, and density are common
to all matter.
Properties of Matter
• You can observe many other properties
of matter using your senses.
• Some properties that are easily
observed include color, texture, odor,
luster, and transparency.
Properties of Matter
Properties of Matter
• Many other properties of matter can be
observed by using simple tests and
measurements.
• Some of these properties include
resistance to breakage, and the ability
to dissolve in water, how they interact
with other substances, and how they are
affected by temperature changes.
Properties of Matter
Explaining Matter's Properties
Explaining Matter's Properties
• Many other properties of matter
are determined by the
characteristics of the particles
themselves.
• For example, particles that
reflect green light give a substance
the property of being green in color.
• The particles in baking soda, not
their arrangement, account for how
it reacts in vinegar.
Explaining Matter's Properties
• The motion of the particles in
matter is also important.
• Particle movement determines
whether a substance will be a solid,
liquid or gas.
Check & Explain pg. 139
Answer Questions 1 & 2
6.2 Phases of Matter
Objectives
• Give examples of solids, liquids,
and gases.
• Relate the particle model to
solids, liquids, and gases.
• Make models illustrating the gas
laws.
Familiar Phases of Matter
• The three most familiar states of matter are
solid, liquid, and gas.
• Each of these states of matter is called a phase.
• Particles of matter in each phase are arranged
differently and have different ranges of motion.
SOLIDS
• When matter has a definite
shape and a definite volume, it is a
solid.
• A solid has these characteristics
because of its closely packed
particles.
• The particles can move slightly,
but they do not change positions.
SOLIDS
• Most solids occur as crystals.
• Salt, bones, diamonds, computer chips,
and snowflakes are all made up of
crystals.
• Particles in a crystal are arranged in a
regular, orderly way.
Liquids
• Matter with a
definite volume, but
no definite shape, is
a liquid.
• Particles in a liquid
easily slide over each
other. As a result, a
liquid will take the
shape of its
container.
Gases
• Matter that has no
definite shape and no
definite volume is a
gas.
• Like a liquid, a gas
will take the shape of
any container.
• Unlike a liquid, a
gas expands to fill
whatever space is
available.
Gases
• Unlike the particles in a solid or
liquid, each gas particle is mostly
unaffected by its neighbors.
• Only temperature and pressure can
affect the way the particles move and
the volume they occupy.
• Because each gas particle is
independent of other gas particles, the
behavior of gases can be described by
general laws.
Gases - Boyle's Law
• A gas sealed in a container exerts a certain
pressure.
• Pressure is the force created by particles
striking the walls of a container.
• You have seen the effect of pressure on the
rubber walls of balloons many times.
• The walls of the balloons are pushed out by
the constant bumping of the gas particles
trapped inside.
Gases - Boyle's Law
• If you squeeze the balloon, the air
inside will be pushed into a smaller
space.
• The air particles will strike the
walls of the container more often.
• The pressure on the walls will
increase.
• If you increase the space, the gas
particles strike the container's walls
less often and the pressure will
decrease.
Gases - Boyle's Law
• This relationship between
pressure and volume is called Boyle's
Law.
• It was discovered by Robert
Boyle, a British scientist who lived in
the 1600s.
• Boyle's Law states that if a
sample of gas is kept at a constant
temperature, decreasing its volume
will increase the pressure the gas
exerts.
Gases - Boyle's Law
• Boyle's Law can be tested using a
cylinder with a movable piston like
the one here.
Gases - Boyle's Law
Animated Boyle's Law
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Gases – Charles Law
• According to Charles' Law, if a sample
of gas is kept at constant pressure, its
volume increases as the temperature
increases.
• Many products in spray cans, such as
whipped cream and paint, contain gas at a
fairly high pressure.
• Their labels warn you to keep them away
from heat or fire. Why?
Answer - Charles Law
• Adding heat energy to a gas causes the gas
particles to move faster.
• When the particles move faster, they
strike the walls of their container harder
and more often. If the container walls aren't
flexible, as in a can of spray paint, the
pressure of the gas will increase.
• Since the can will withstand only so much
pressure, the result could be explosive and
dangerous!
Gases – Charles Law
• However, if a gas in a
container with flexible
walls is heated, the volume
of the gas will increase.
• What happens when the
same balloon is cooled?
Gases – Charles Law
Plasmas
• At very high temperatures, over 1
1,000,000 0C, gas particles break
down, forming a plasma.
• Plasma, called the fourth phase
of matter, is the most common
phase of matter in the universe.
• The sun and other active stars
are made up mostly of plasmas.
These plasmas are formed from the
gases hydrogen and helium.
Plasmas
• Plasmas have unusual properties
that gases do not have.
• Temperatures high enough to form
plasmas exist naturally only in stars.
• On earth, plasmas can be
manufactured and studied only in
special laboratories able to handle the
extreme temperatures at which
plasmas exist.
Check & Explain pg. 146
Answer Questions 1 & 2
6.3 Changes in Matter
OBJECTIVES:
• Give examples of physical and chemical
changes.
• Compare and contrast physical and
chemical changes.
• Interpret data about a phase change.
Physical Changes in Matter
• When matter undergoes a change in size,
shape, or phase, it is a physical change.
• Breaking glass, cutting wood, grinding coffee
are all physical changes.
• Is freezing water a physical change?
• Physical changes do not change the particles
that make up matter. The arrangement of the
particles, however, may be moved around
during a physical change.
Physical Changes in Matter
• Are you causing a physical change when
you mix sugar and water?
• A mixture of salt or sugar and water can
be compared to a mixture of water and
pebbles.
• The pebbles can be separated with a
strainer.
• Salt or sugar particles are too small for
you to separate by hand or strainer.
However, the water can be boiled away,
leaving the salt or sugar behind.
Physical Changes in Matter
• Physical changes help shape the
earth's surface.
Chemical Changes in Matter
• In a chemical change, particles of one
substance are changed in some way to
form particles of a new substance that
has new and different properties.
• The production of heat or light, the
appearance of gas bubbles, and the
formation of a solid all indicate that a
chemical change has taken place.
Physical vs. Chemical Changes
• The earth’s surface is shaped by chemical
changes as well as physical changes.
• Gases in the atmosphere and water combine with
minerals in rocks to create new substances.
These chemical changes weaken rocks so that
they chip, crack, and break apart more easily.
• Chemical weathering happens to rocks all over
the earth's surface.
• Chemical changes work together with physical
changes to weather and erode the earth's
surface.
Physical vs. Chemical Changes
• A chemical change makes a substance
that wasn't there before.
• There may be clues that a chemical
reaction took place, such as light,
heat, color change, gas production,
odor, or sound.
Physical vs. Chemical Changes
• The starting and ending materials of a
physical change are the same, even
though they may look different.
• Any change in phase, for example, can
be reversed. Ice can melt to form
water and water can freeze to form
ice.
• Usually only physical changes can be
reversed.
Physical or Chemical Change ?
•
•
•
•
•
•
•
•
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When you freeze water ( P )
Casting silver in a mold ( P )
When you burn wood in your fireplace ( C )
When iron (Fe) rusts ( C )
Melting a sugar cube ( P )
When you step on a can and crush it ( P )
When you cook an egg ( C )
Solid iodine evaporating into a purple gas ( P )
Taking an antacid to neutralize stomach acid ( C )
Check & Explain pg. 151
Answer Question 3