Chapter 10
States of Matter
Section 1:
The Kinetic-Molecular
Theory of Matter
Standard 4.b.
 Students know the random motion of molecules
explains the diffusion of gases.
Objectives
 We will list the five assumptions of the kinetic-
molecular theory of gases and describe the
properties of gases.
KMT
 This is based on the idea that particles of
matter are always in motion.
How it relates to gases:
 Ideal gas = a hypothetical gas that
perfectly fits all the assumptions of KMT.
 No ideal gas actually exists; but some do
come close.
5 Assumptions
 Gases consist of large numbers of tiny particles
that are far apart relative to their size.
 Collisions between gas particles and between
particles and container walls are elastic
collisions (no net loss of total kinetic energy)
 Gas particles are in continuous, rapid, random
motion. Thus, they have kinetic energy.
5 Assumptions Cont.
 There are no forces of attraction between gas
particles.

This is why they have no set shape
 The temperature of the gas depends on the
average kinetic energy of the particles of the
gas.
Standard 4.b.
 Students know the random motion of molecules
explains the diffusion of gases.
Objectives
 We will list the five assumptions of the kinetic-
molecular theory of gases and describe the
properties of gases.
Properties of Gases
 No definite shape
 Can be compressed
 No definite volume
smaller
 Diffusion
 Effusion
 Ability to flow (fluid)
 Low density
Real Gases
 A gas that does not behave completely
according to the assumptions of KMT.
 Noble gases and non-polar diatomic
gases behave most like an ideal gas,
as well as gases at high temperatures
and low pressures.
Standard 4.b.
 Students know the random motion of molecules
explains the diffusion of gases.
Objectives
 We will list the five assumptions of the kinetic-
molecular theory of gases and describe the
properties of gases.
Section 2 & 3:
Liquids and Solids
Standard 4.a.
 Students know the random motion of molecules
and their collisions with a surface create the
observable pressure on that surface.
Objectives
 We will describe the properties of liquids and
discuss the processes of how liquids change.
 We will describe the properties of solids and
distinguish between the two types of solids.
Properties of Liquids
 No definite shape
 Surface tension
 Higher density
 Evaporation
 Mostly incompressible
 Boiling
so definite volume
 Diffusion
 Can form solids
Properties of Solids
 Definite shape
 High density
 Definite volume
 Incompressible
 Defined melting
 Low rate of
point
diffusion
Types of Solids
 Crystalline Solids: exist as single
crystals or groups of crystals fused
together.
Ionic Crystals
 Covalent Network Crystals
 Metallic Crystals
 Covalent Molecular Crystals

Types of Solids
 Amorphous Solids: are not
arranged in a regular pattern.
 Glass and Plastic
Standard 4.a.
 Students know the random motion of molecules
and their collisions with a surface create the
observable pressure on that surface.
Objectives
 We will describe the properties of liquids and
discuss the processes of how liquids change.
 We will describe the properties of solids and
distinguish between the two types of solids.
Chapter 10.4
Changes of State
Standard 7.c.
 Students know energy is released when a
material condenses or freezes & is absorbed
when a material evaporates or melts.
Objectives
 We will describe the processes that occur to
cause a change of state.
 We will interpret phase diagrams.
 Matter on earth can exist in any state—
gas, liquid, or solid—and can change
from one state to another.
Energy and Changes of State
 When a substance changes from one
state to another, energy is always
involved.
 The change will either be exothermic
(releases heat) or endothermic
(absorbs heat).
Changes of State
Change of State
Process
Example
SolidLiquid
Melting
IceWater
SolidGas
Sublimation
Dry IceCO2
LiquidSolid
Freezing
WaterIce
LiquidGas
Vaporization
WaterSteam
GasSolid
Deposition
SteamIce
GasLiquid
Condensation SteamWater
Endo or
Exo?
Standard 7.c.
 Students know energy is released when a
material condenses or freezes & is absorbed
when a material evaporates or melts.
Objectives
 We will describe the processes that occur
to cause a change of state.
 We will interpret phase diagrams.
Phase Diagrams
 Phase Diagram: a graph of pressure versus
temperature that shows the conditions under
which the phases of a substance exist.
 Tells you what state a substance will be in at
a certain temperature and pressure.
 Triple point: the temperature and pressure
conditions at which the three phases can
coexist at equilibrium
 Critical Point: the highest temperature and
pressure that a substance can exist as a
liquid.
 Critical Temperature: the temperature
above which the substance cannot exist
as a liquid.
 Critical Pressure: the lowest pressure
at which the substance can exist as a
liquid.
Name that state…
Temperature Pressure
70°C
2.0 atm
100°C
0.5 atm
0°C
1.0 atm
State
Name that state…
Temperature Pressure
State
70°C
2.0 atm
Liquid
100°C
0.5 atm
Gas
0°C
1.0 atm
Solid
Standard 7.c.
 Students know energy is released when a
material condenses or freezes & is absorbed
when a material evaporates or melts.
Objectives
 We will describe the processes that occur to
cause a change of state.
 We will interpret phase diagrams.
Homework
 Pg 332 #2, 3
 Pg 336 #4, 5
 Pg 341 #2
 Pg 348 #6
Chapter 10.5
Water
Standard 7.c.
 Students know energy is released when a
material condenses or freezes & is absorbed
when a material evaporates or melts.
Objectives
 We will describe the structure of the water
molecule and its properties.
 We will calculate the amount of energy
absorbed or released when water changes
state.
Structure of Water
 Recall: Water has 2 Hydrogen and 1 Oxygen
and has a bent structure.
 Ice forms a hexagonal pattern
 Look at Fig 19 on pg 350
 The empty spaces result in
ices low density and are why
it floats.
Properties of Water
 Pure water is transparent, odorless, tasteless and
almost colorless. Any odor or taste is caused by
impurities.
 Water freezes and ice melts at 0°C and 1 atm.
 Molar enthalpy of fusion is 6.009 kJ/mol
 Water boils at 100°C and 1 atm.
 Molar enthalpy of vaporization is 40.79 kJ/mol
 Going from ice to water requires energy.
 Going from water to ice releases energy.
 Going from water to steam requires energy.
 Going from steam to water releases energy.
 The amount of energy is the same, it is just
either required or released.
Standard 7.c.
 Students know energy is released when a
material condenses or freezes & is absorbed
when a material evaporates or melts.
Objectives
 We will describe the structure of the water
molecule and its properties.
 We will calculate the amount of energy
absorbed or released when water changes
state.
Calculating Amount of Energy
 What quantity of energy is released when 804 g
of water vapor condenses?
 Convert from grams to moles
 Multiply moles by 40.79 kJ/mol (Vaporization)
 Moles cancel out, units are kJ
 Answer = 1820 kJ
Calculating Mass from Energy
 What mass of ice is required to release
2000 kJ of energy when melting?
 Divide kJ by 6.009 kJ/mol (fusion)
 kJ cancel out so you have moles.
 Convert moles to grams.
 Answer = 6000 g H2O
Standard 7.c.
 Students know energy is released when a
material condenses or freezes & is absorbed
when a material evaporates or melts.
Objectives
 We will describe the structure of the water
molecule and its properties.
 We will calculate the amount of energy
absorbed or released when water changes
state.
Homework
 Pg 351 #4, 6 and practice problem #1, 2