chapter 10 states of matter. section 1: the kinetic-molecular theory of matter
TRANSCRIPT
Chapter 10States 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.
We will list the five assumptions of the kinetic-molecular theory of gases and describe the properties of gases.
Objectives
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.
We will list the five assumptions of the kinetic-molecular theory of gases and describe the properties of gases.
Objectives
Properties of Gases
No definite shapeNo definite volumeAbility to flow (fluid)Low density
Can be compressed smaller
DiffusionEffusion
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.
We will list the five assumptions of the kinetic-molecular theory of gases and describe the properties of gases.
Objectives
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.
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.
Objectives
Properties of Liquids
No definite shapeHigher densityMostly incompressible
so definite volumeDiffusion
Surface tensionEvaporationBoilingCan form solids
Properties of Solids
Definite shapeDefinite volumeDefined melting
point
High densityIncompressibleLow rate of
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.
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.
Objectives
Chapter 10.4Changes of State
Standard 7.c.
Students know energy is released when a material condenses or freezes & is absorbed when a material evaporates or melts.
We will describe the processes that occur to cause a change of state.
We will interpret phase diagrams.
Objectives
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 Endo or Exo?
SolidLiquid Melting IceWater
SolidGas Sublimation Dry IceCO2
LiquidSolid Freezing WaterIce
LiquidGas Vaporization WaterSteam
GasSolid Deposition SteamIce
GasLiquid Condensation SteamWater
Standard 7.c.
Students know energy is released when a material condenses or freezes & is absorbed when a material evaporates or melts.
We will describe the processes that occur to cause a change of state.
We will interpret phase diagrams.
Objectives
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 critical temperature and critical pressure of a substance.
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 State
70°C 2.0 atm
100°C 0.5 atm
0°C 1.0 atm
Name that state…
Temperature Pressure State
70°C 2.0 atm
100°C 0.5 atm
0°C 1.0 atm
Liquid
Gas
Solid
Standard 7.c.
Students know energy is released when a material condenses or freezes & is absorbed when a material evaporates or melts.
We will describe the processes that occur to cause a change of state.
We will interpret phase diagrams.
Objectives
Homework
Pg 332 #2, 3Pg 336 #4, 5Pg 341 #2Pg 348 #6
Chapter 10.5Water
Standard 7.c.
Students know energy is released when a material condenses or freezes & is absorbed when a material evaporates or melts.
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.
Objectives
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.
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.
Objectives
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.
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.
Objectives
Homework
Pg 351 #4, 6 and practice problem #1, 2