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1
Phases & Behavior
of Matter
Chs 13, 17,
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Phases and Behavior of Matter Goals
a. Understand the effects motion of atoms and molecules
in chemical and physical processes.
b. Compare and contrast atomic/molecular motion in solids,
liquids, gases, and plasmas.
c. Collect data and calculate the amount of heat given off or
taken in by chemical or physical processes.
d. Analyzing (both conceptually and quantitatively) flow of
energy during change of state (phase).
e. Apply concepts of the mole and Avogadro’s number to
conceptualize and calculate molar volumes of gases.
Solid
Liquid
Gas
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Kinetic Theory of Matter
1) All matter is composed of small particles (atoms).
2) These particles are in constant motion.
3) These particles are colliding with each other and
the walls of their container.
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Kinetic Energy
• Kinetic Energy is the energy of motion.
• Temperature is the measurement of the KE in an
object.
• So, the more KE the higher the temp.
• As the particles in an object gain KE, the
temperature goes up.
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Solids
• Particles are closely packed
together.
Particles
are closely packed
•• Most
are geometric.
(called
together.
Crystals)
• Most are geometric. (called
Crystals)
• There are bonds between
atoms/mol.
• Rigid shapes.
• Definite shape.
• Definite volume.
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Amorphous Solids
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Amorphous Solids
•Crystalline solids
are arranged in
fixed geometric
patterns or lattices.
• Lack highly “without form”
ordered
internal
arrangement
•Amorphous solids are
solids with random
• Melt over a
unoriented molecules
temperature
range
• Glass
– Super-cooled
liquid
• Plastics
• Some scientist
classify them
as “thick
liquids”
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Clip
Liquids
• Particles in a liquid have more KE than
particles in a solid.
• Liquid particles have enough KE to overcome
the forces that hold them together.
• The particles can now move past one another.
(flow)
• Definite volume
• No Definite shape.
Viscosity
• Resistance to flow
Viscosity
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Gases
• Gas particles have
more KE than liquid
particles.
• They have enough
energy to break all
bonds and escape the
liquid state.
• Particles are far apartno attractice forces
between them
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Gases
• Motion of the molecules
is random.
• During collisions
between particles, KE is
transferred without loss
of total energy.
• No definite Shape
• No definite Volume.
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Gases are compressible
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o Most common state
of matter in the
universe
o Extremely high
temperatures.
o Contains positively
and negatively
charged particles
Plasma
Clip
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Artificially produced plasmas
Terrestrial plasmas
•Those found in plasma
displays, including TVs
•Lightning
•Inside fluorescent lamps (low
energy lighting), neon signs
•The ionosphere
•The electric arc in an arc lamp,
an arc welder or plasma torch
•Plasma ball (sometimes called a
plasma sphere or plasma globe)
•The polar aurorae
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o Force produced by high
energy collisions strips
electrons from atoms.
o Sun, lighting bolts, neon and
fluorescent tubes, auroras.
ReviewClip
Gasses exert pressure on the walls of
their containers and objects around them.
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• Pressure- measure in Pa
• Atmospheric pressure- • Conversions- Units
of pressure
collision of atoms and
molecules in the air with • (Q) What is
object.
450kPA in mmHg
and atm?
-Standard pressure (atm)
at 25˚C
• Barometer- measure
atm pressure
– 4.4 atm
– 3.4 x 103 mm Hg
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Calculating molar volumes of gases
• The molar volume is the volume occupied by
one mole of ideal gas at STP.
– Its value is:
22.414 L/mol
..so 1 mol of any gas has a volume of 22.4 L… @ STP
1 mol
22.4 L
Standard Pressure = 1 atm
Standard Temperature = 0 deg C
(273 K)
Goals: Apply concepts of the mole and Avogadro’s number to conceptualize and
calculate molar volumes of gases
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molar volumes of gases
Practice Problems
2 H2O2 (l) ---> 2 H2O (g) + O2 (g)
Decompose 1.1 g of H2O2 in a flask with a volume of 2.50 L.
What is the volume of O2 at STP?
1.1 g H2O2
1 mol H2O2 1 mol O2
22.4 L O2
34 g H2O2 2 mol H2O2 1 mol O2
= 0.36 L O2 at STP
Cool Fact: Bombardier beetle
uses decomposition of hydrogen
peroxide to defend itself.
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molar volumes of gases
1. What volume is occupied by 10 moles of ammonia,
NH3, at standard conditions? 224 liters
2. What is the volume occupied by 40 grams of argon
gas (Ar) at standard conditions? 22.4 liters
3. What volume, in liters, is occupied by 1.5 x 1023
atoms of argon gas (Ar) at STP? 5.6 liters
4. What volume would be occupied by 120 grams of
argon gas (Ar) at standard conditions? 67.2 liters
5. What volume will 0.750 moles of nitrogen gas
occupy at STP? 16.8 L N2
6. How many moles are contained in 2.500 liters of
methane (CH4) at STP? 0.112 mol CH
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C3H8 (g) + 5 O2 (g)  3 CO2 (g) + 4 H2O (g)
1. What mass of H2O is produced if 50.0 %
of CO2 is produced at STP?
2. How many moles of gas are present in 11.2 L
at STP?
How many molecules?
3. How many molecules of O2 are present in
56.0L at STP?
56L
1 mol
22.4 L
6.022 x 1023 molecules
1 mol
=
1/10 mole
4. A sample of carbon dioxide gas (CO2) contains 6 x
1022 molecules. How many moles of carbon dioxide
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Measuring Heat
• Heat is a form of energy, and it is
measure in Joules or Calories.
• Calorie; the quanity of heat needs to
raise the temperature of 1g of pure
water 1˚C.
• Note: Dietary Calorie is actually 1kcal.
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Specific Heat
• Adding Energy to a
material Causes the…
– Temperature to go
up.
• Taking energy away
from a substance
causes the temp. to…
– Go down!
Specific means “certain”
Which would heat up
faster? The aluminum or
the plastic?
• Have you ever noticed that on a hot
summer day the pool is cooler than
the hot cement?
• OR maybe that the ocean is cooler
than the hot sand?
• Why? The sun has been beating
down on (delivering energy to) both
of them for the same amount of
time.....same amount of energy.
• It takes more thermal energy to
raise the temperature of water
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that it does the cement!
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Specific Heat
• The amount of energy required
to raise the temperature of a
material (substance).
• It takes different amts of
energy to make the same temp
change in different substances.
• We call the amt required:
Specific Heat!
28 Every materials requires a different amount of
energy to change its temperature.
(Cp )
Cp Stands for “Heat Capacity”
Note: The lower the number, the FASTER the material heats
up….and cools down
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Specific Heat of water
• The Cp is high because H2O
mols. form strong bonds
w/each other.
• It takes a lot of energy to
break the bonds so that the
the molecules can then start
to move around faster
(HEAT UP).
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Calculating Amount of Heat
p
The Greek letter Δ means “change in”
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EXAMPLE :
• What amount of heat is required to raise the
temperature of 85.9 kg of water by 7C? The
specific heat of water is 4.184 J/gC.
• Mass = 85.9kg
• Q = ?
• Δt = 7°
• Cp = 4.184 J/g-C?
• Q =m x Cp x Δt
• Q= (85.9kg)(4.184 J/g-C)(7°C)
• Q= 2515.8 J
• (WHAT DOES THAT MEAN?)
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Can you get a negative “Q”
• Q =m x Cp x Δt
• Yes.
• If the object is LOSING heat.
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Specific Heat Practice with a friend….
1. How much heat must be absorbed by 375 grams of
3.9 x 104 J
water to raise its temperature by 25° C?
2. How much energy (in calories and in Joules) will it take
to raise the temperature of 75.0 g of water from 20.0
2630 cal and 1.1 x 10 4 J
to 55.0 oC?
3. What is the heat in Joules required to raise the
temperature of 25 grams of water from 0 °C to 100
°C? What is the heat in calories? 10450 J or 2500 calories
4. It takes 487.5 J to heat 25 grams of copper from 25
°C to 75 °C. What is the specific heat in Joules/g·°C?
0.39 J/g·°C.
5. 350 J are released as ice ( Specific Heat = 2.1 J / (g
oC) ) cools from - 5.0 oC to -32 oC. What is the mass
of ice?
6.2 g
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Changing State
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Sublimation
• Some substances go from the solid state directly
to the gaseous state. This happens when a
substance was below it freezing point and is
suddenly moved to a location where it is above
its boiling point
• EX: CO2
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Boiling Point and Pressure
• Water boils at
about 95 degrees
C in Denver and
higher than 100
degrees C in a
pressure cooker.
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•It takes energy to cause phase changes( soild-liq-gas)
•Removal of energy (gas-liq-solid)
Phase changes do not change the
substance
Clip
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42 •
The amount of
energy required for a
substance to go from
a solid to a liquid is
called the
HEAT OF FUSION.
• (EX) it takes 334,000
Joules of energy to
melt 1 kg of ice. No
temperature change.
0°C
0°C
NO TEMP CHANGE
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• The amount of energy
required to change a
liquid to a gas is
called the
…Heat of Vaporization
• EX: It takes 2,260,000
Joules of energy to
vaporize 1 kg of water.
100 °C
100 °C
NO TEMP CHANGE
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Practice
Problems
Information: H20
Heat of Fusion (hf) = 334 J/g
Heat of vaporization (hv) =2260 J/g
1. What is the heat in Joules
required to convert 25 grams of
water into steam? What is the
heat in calories?
56425 J, 13,500 cal
2. What is the heat in Joules
required to melt 25 grams of ice?
What is the heat in calories?
8350 Joules or 2000 cal
3. How much energy would be
required to melt 15.0 g of ice at 0
oC?
5.01 KJ
4. How much energy would it take to
boil 36.0 g of water at 100 oC?
81.4 KJ
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Combination Problems….
You can do this 
• How much energy would it take to melt 30.0 g of
ice at 0 oC and warm the resulting liquid to 35.0 oC?
– 14.4 KJ
• How much energy would it take to warm 30.0 g of
water at 35 oC to the boiling point and boil all the
liquid away?
– 76 KJ
• How much energy would be reqired to melt 10.0 g
of ice at 0 oC, warm the resulting liquid to 100 oC,
and change it to steam at 100 oC?
– 30.1 KJ
46 • Phase depends
not only on
temp. but also
pressure.
• The triple point of a
substance is the temp.
and pressure at which
the three phases of that
substance coexist
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Phase
depends
not only
on temp.
but also
pressure.
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When heat is added to most materials they expand
Thermal Expansion
• When objects are heated,
they expand.
• When they are cooled, they
contract.
• Video Clip
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Thermal Expansion
• Thermometers:
Work because of
thermal expansion.
Typical expansion
joints on a steel
span bridge.
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Gases exert pressure on their
container
Pressure (Pa)=
Force (N)
Area (M2)
The Pascal (Pa) is the SI
• Pressure: The amt of force
exerted per unit of area.
• Gases exert pressure by
colliding with “things.”
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1.Other particles of gas
2.Sides of the container
3.Objects within the area of the
gas, like you.
Clip
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Boyle’s and Charles’ law
• Both deal with gases.
• Boyle’s Law
– As the volume
decreases, the
pressure increases.
• Charles’ Law
– As the temperature
decrease, the volume
of a gas decreases.
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Boyle’s Law
• Relationship between volume
and pressure.
You tube
Clip
P1V1 = P2V2
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Boyle’s Law
P1V 1 = P 2V 2
If you
decrease
the
volume,
the
pressure
will
increase
( no Δt)
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Charles’ Law
• Relationship between volume and
temperature.
In theory there is a
temperature in which gases
ceases to have volume.
This temp. is referred to
as absolute zero.
Absolute Temp. Scale
T (K) = °C + 273.15 K
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Charles’ Law
If you increase the temperature,
the volume will increase
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Gay-Lussac’s Law
If n and V are constant,
then P α T
P and T are directly
proportional.
• If one temperature
goes up, the pressure
goes up!
Joseph Louis GayLussac (1778-1850)
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• PHET Gas Properties simulation
• PHET States of Matter simulation
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The
End