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Chapter 16
Phases of Matter
Physical Science
What makes up matter?
What is the difference between a solid, a
liquid, and a gas?
What kind of energy do all particles of
matter have?
Kinetic theory Kinetic Theory
3 Parts
1. All matter is made of tiny particles.
2. These tiny particles are always in
motion. The higher the temperature, the faster the
particles move.
3. At the same temperature, more
massive (heavier) particles move slower
Animation
Kinetic Molecular Theory:
This motion is different for the 3 states of matter.
Copyright © 2010 Ryan P. Murphy
6
State the three parts of Kinetic Theory
Kinetic theory
States of Matter
When a substance
changes from one
phase of matter to
another, the identify
of the substance
does NOT change.
• Water freezes to a
solid and melts to
a liquid, but it is
still just water.
States of Matter Microscopic view of matter
• Activity! Describing Solid-Liquid-Gas
– Possible Answers!
Solid Liquid Gas
Volume
Shape
Mass
Copyright © 2010 Ryan P. Murphy
Easy to find –
in ml or cm3
Many different
forms. Easy
to mold.
Generally
Heavy / Weigh
in grams
Easy to find.
Easy to find.
Use graduated
cylinder – ml
Takes shape
of the
container.
Generally
Heavy / Weigh
in grams.
Difficult to find in
a classroom .
No Shape
Lighter in mass /
Harder to weigh
in a classroom
SOLIDS
•Solids have a definite shape and
volume
•The particles are held closely together
by strong attractions
•Packed close together
•Vibrate in place.
•Don’t flow
States of Matter
Characteristics of Solids
_______ have a rigid
structure.
– They do not need
a container to
maintain shape.
But they can still
________ in
place.
Solids
vibrate
Fill in the blanks
Characteristics of Solids
Definite
volume and a
definite shape.
Particles are
packed close
together in
relatively fixed
positions.
Particles are
held by strong
attractive forces
between them.
Particles vibrate
about in a fixed
position.
LIQUIDS
States of Matter
1. Has a definite volume but no definite shape. • Volume remains the same, but shape changes.
2. Take shape of container.
3. Particles are held close together but can
flow freely.
4. The particles in a liquid move much faster
than in a solid. • This allows the particles of a liquid to temporarily
overcome the attractive forces between them.
Characteristics of Liquids
________ can fill the
bottom of their container.
Particles are close
together, but not as close
as particles in a
_________.
Liquids
solid
Characteristics of Liquids
Definite
volume and not
definite shape.
Particles
are close
together
Takes shape
of container
Particles flow
freely and slide
past each other
GASES
States of Matter
Characteristics of Gases
A ______ expands to fill any available
space.
–_______ can exert pressure on their
container.
gas
Gases
•These particles are approximately 10 times farther
apart than those of a liquid or solid.
Characteristics of Gases
Gases
Gases
Gases
Attractive forces
between gas
particles are much
weaker than those in
liquids and solids.
Particles move very
rapidly and are at
great distance from
one another.
No definite
shape nor
definite volume.
PLASMA
States of Matter
Characteristics of Plasma
Ionized gas that emits electrons.
High-energy plasma collides
with gas particles.
• Plasmas are similar to gases but have some properties
that are different. • Example: plasmas conduct electric current, while gases do
NOT!
• The glow of fluorescent light is caused by artificial plasma
which is formed by passing electric currents through gases.
PLASMA
States of Matter
Energy is the ability to change or move
matter, or to do work.
The energy of motion is called kinetic energy
Because atoms and molecules are always in
motion, all particles of matter have kinetic
energy.
Energy’s Role
Energy’s Role
Which is a solid,
which is a liquid,
and which is a gas?
Gas
Solid
Liquid
• Identify as a Solid, Liquid, Gas, Plasma
Copyright © 2010 Ryan P. Murphy
Chapter 16 Changes of State
• What happens when a substance changes
from one state of matter to another?
• What happens to mass and energy during
physical and chemical changes?
Energy and Changes of State
– The identity of a substance does not change
during a change in state
– The ability to change or move matter
• As you add energy to a liquid, the temperature
goes up separating molecules
– Some changes of state require energy
• Melting, evaporation and sublimation
• The change of state from a liquid to a gas
Energy and Changes of State
• Boiling Point- The temperature
at which a liquid boils.
• The temperature of boiling water is
100oC on the celsius scale and 212oF
on the Fahrenheit scale.
• The temp in the room is about 22°C
and 70°F.
• Are the following temperatures hot or
cold?
65°F
• The process in which a solid changes
directly into a gas
Sublimation
Ex. Dry ice (Carbon dioxide in the solid
form) changes directly from a solid to a gas
Video Clip
Melting Point • The temperature at which a substances
changes from solid to liquid.
• Melting point depends on the pressure.
32 degrees F
0 degrees C
• Energy is released in some changes of
state
– Freezing and condensation
Name the physical phase
change
Copyright © 2010 Ryan P. Murphy
Freezing
Melting
Sublimation
Evaporation
Condensation
Solid Liquid Gas
sublimation
Freezing Condensation
Melting Boiling or
evaporation
46
Look at the vertical
lines.
What is the energy
doing if it is not
increasing the
temperature?
Why are the
arrows on each
side of the graph
the same
length?
En
erg
y o
f S
yste
m
• Please sketch the following into your
notes
Copyright © 2010 Ryan P. Murphy
What is the name of the first
electricity detective?
Sherlock Ohms
Joke of the Day
Copyright © 2010 Ryan P. Murphy
Energy
Energy
Sublim
ation
Depositio
n
Copyright © 2010 Ryan P. Murphy
• The temperature of a substance does not
change during a change of state. – For example, if you add energy to ice at 0oC,
the temperature will NOT rise until all of the
ice has melted.
– When energy is added – Move up a step.
– When energy is removed – Go down a step.
Heat added
Tem
pera
ture
(oC
)
0
100
Melting
Ice
Water
Water Vapor Boiling
Copyright © 2010 Ryan P. Murphy
• Latent Heat: The energy absorbed or
released when a substance changes its
physical state.
Heat added
Tem
pera
ture
(oC
)
0
100
Melting
Ice
Water
Water Vapor Boiling
Latent Heat
Latent Heat
Copyright © 2010 Ryan P. Murphy
• Mass cannot be created or destroyed.
• Matter can change form, and turn into different forms, but the TOTAL mass stays the same.
• Gas has mass!
Conservation of Mass and Energy
The Law of conservation of energy
• Energy cannot be created or destroyed.
– Energy can convert from one form to another,
but the TOTAL energy, before and after the
change, is the same.
Conservation of Mass and Energy
• In any physical or chemical change, matter is
neither created nor destroyed
– Matter can be changed from one form to another.
Copyright © 2010 Ryan P. Murphy
Heat
Law Conservation of Matter
Conservation of Mass and Energy
• Law Conservation of Matter
Copyright © 2010 Ryan P. Murphy
Chapter 16 Fluids • How do fluids exert pressure?
• What force makes a rubber duck float in a
bathtub?
• What happens when pressure in a fluid
changes?
• What affects the speed of a fluid in motion?
Fluids • A nonsolid state of matter in which the atoms
or molecules are free to move past each
other.
• Liquids and gases are fluids, because their
particles can move past each other.
• Pressure is the amount of force exerted
on a given area of surface.
• Fluids exert pressure evenly in all
directions. How does the pressure change if you remove
some of the air?
Pressure
• The SI unit of pressure is the pascal.
– One pascal (1 Pa) is the force of one newton exerted over an area of one
square meter (1N/m2).
• The newton is the SI unit of force.
Pressure
Pressure = force
area P = F
A
Blaise Pascal
• Buoyancy is the force with which a more
dense fluid pushes a less dense fluid
substance upward.
• All fluids exert an upward buoyant force on
matter.
• Archimededs’ principle is used to find
buoyant force.
Buoyant Force
How does this relate to me?
–Buoyancy tells me whether or
not an object will float.
Archimedes Principle
• The buoyant force on an object in a fluid
is an upward force that equals the weight
of the fluid that the object displaces.
Buoyant Force
65
Archimedes Principle
• Explains
why a
steel
ship
floats!
Density
• An object will float or sink
based on its density.
• You can determine if a
substance will float or sink by
comparing densities.
Buoyant Force
Pascal’s Principle
• A change in pressure at any point in an enclosed fluid
will be transmitted equally to all parts of the fluid.
P=force/ area
Hydraulic devices are based
on Pascal’s Principle.
How does this relate to me?
Viscosity tells me how
thick a liquid or gas is.
Fluids In Motion
• Fluids move faster through small areas
than through larger areas.
• Rates at which they flow also varies.
• Viscosity is the resistance of a fluid to
flow.
Which has a greater
viscosity? Water or honey
Stronger attraction between particles, the more viscous
69
Chapter 16 Behavior of Gases
• What are some properties of gases?
• How can you predict the effects of
pressure, temperature, and volume
changes on gases?
Think about this…….
The gas in the toy balloon expands outward, as shown below. After this expansion, does the pressure of the gas
a. increase?
b. decrease?
c. remain unchanged? The temperature of the water vapor in the pressure cooker increases. Does the pressure of the gas a. increase? b. decrease? c. remain unchanged?
Volume goes up
Pressure goes down
Temperature increases
Pressure increases
Properties of Gases
• Have low densities and are
compressible.
• Mostly empty space.
• Gases fill containers
uniformly and completely.
• Gases diffuse and mix
rapidly.
• The gas laws will help you understand
and predict the behavior of gases in
specific situations.
• Boyle’s Law (relates pressure to volume)
• Gay-Lussac’s Law (relates pressure to temperature)
• Charles’s Law (relates temperature to volume)
Gases Laws
Boyle’s Law
Robert Boyle
(1627-1691).
Son of Earl of
Cork, Ireland.
• Boyle’s law relates the pressure of a
gas to its volume.
• For a constant temperature, as the
pressure goes up the volume goes
down.
• As the volume goes up the pressure
goes down.
Gases Laws
Pressure Volume
Temperature is constant
• A bicycle pump is an
example.
• As the volume of the
air trapped in the
pump is reduced, its
pressure goes up, and
air is forced into the
tire.
Gases Laws
Boyle’s Law
(pressure1) (volume1) = (pressure2) (volume2)
P1V1 = P2V2
Gases Laws
Boyle’s Law
The gas in a balloon has a volume of 7.5 L at 100.0 kPa. In the atmosphere,
the has expands to a volume of 11 L. Assuming a constant temperature, what
is the final pressure in the balloon?
V1 =
P1=
V2 =
P2 = ?
V1 = 7.5 L
P1= 100.0 kPa
V2 = 11 L
P2 = ?
P1V1 = P2V2
P2= P1V1
V2
P2= (100.0 kPa)(7.5 L)
11 L
P2= 68 kPa
• Relates gas pressure to temperature.
• The pressure of a gas increases as the
temperature increases.
• If the volume of the gas does not change.
The pressure decreases as the
temperature decreases.
Gases Laws
Gay-Lussac’s Law
Volume is constant
Pressure Temperature
P lower in winter than summer
• Charles’s law relates temperature to volume.
• For a fixed amount of gas at a constant
pressure, the volume of the gas increases as the
gas’s temperature increases.
• Likewise, the volume of the gas decreases as
the gas’s temperature decreases.
Gases Laws
Charle’s Law
Pressure is constant
Volume Temperature
Charles’s Law