Starter S-137

List and describe the four states of matter.

States of Matter

Chapter 13

13.1 The Nature of Gases

Chapter 13

Kinetic Theory – all matter consists of tiny particles that are in constant motion

1. The particles of a gas are considered to be small hard spheres with an insignificant volume

2. The motion of the

particles in a gas is

rapid, constant, and

random

13.1 The Nature of Gases

3. Collisions between particles in a gas are perfectly elastic.

-no energy is lost in

collisions

13.1 The Nature of Gases

Gas pressure is caused by the collision of particles with the container

Atmospheric Pressure – caused by the collision of atoms and molecules in air with objects

13.1 The Nature of Gases

PhET Gas

Barometer – a device to measure atmospheric pressure

The pressure depends on

Temperature

Altitude

Measured in pascal (Pa)

very small unit

13.1 The Nature of Gases

kPaPaatm 3.101300,1011

Units must be converted for problems to work out

These are equalities, so they can be used to create conversion factors

13.1 The Nature of Gases

torrmmHgkPaPaatm 7607603.101300,1011

atmmmHg

atmmmHg 059.0

760

145

kPaatm

kPaatm 96

1

3.10195.0

The Kelvin temperature of a substance is directly proportional to the average kinetic energy of the particles of the substance

13.1 The Nature of Gases

PhET Gas

Notice- the average shifts, but there are particles with very different temperatures- the hotter one has particles with almost no energy, just like the colder one- this is a change in kinetic energy, not speed

13.1 The Nature of Gases

Starter S-139

Convert each of the following to kilopascals

1. 450 mmHg

2. 1045 torr

3. 1.29 atm

4. 95,000 pa

13.2 The Nature of Liquids

Chapter 13

Fluids – substances that

can flow

gases

liquids

Unlike gases, liquids particles

attracted to

each other

13.2 The Nature of Liquids

Physical properties of a liquid are determined by

1. Motion of the particles (due to temperature)

2. Attraction among the particles

3. The particles are

closer together

due to these

forces

13.2 The Nature of Liquids

Phase Change

Vaporization – conversion of a liquid to a gas or vapor

Evaporation – vaporization on

the surface of a liquid that is

not boiling

13.2 The Nature of Liquids

During evaporation – only molecules with a certain minimum kinetic energy escape from the liquid

Evaporation takes

away the hot (faster) particles and is a

cooling process

13.2 The Nature of Liquids

Vapor Pressure – the force exerted by a gas above a liquid

Because of the gas

produced by evaporation

Eventually particles leaving the liquid equal the particles reentering the liquid

13.2 The Nature of Liquids

Vapor Pressure

Equilibrium

The container only reaches equilibrium if it is sealed

Vapor pressure depends on temperature

at higher temperature the average kinetic energy is higher

13.2 The Nature of Liquids

Vapor Pressure (kPa)0oC 20oC 40oC 60oC 80oC 100oC

Water 0.61 2.33 7.37 19.92 47.34 101.3

Ethanol 1.63 5.85 18.04 47.02 108.3 225.8

Diethyl ether 24.70 58.96 122.8 230.6 399.1 647.9

The vapor pressure shows of volatile a liquid is

How easily it evaporates

13.2 The Nature of Liquids

Boiling – when the temperature is high enough, that particles throughout the liquid have the kinetic energy to vaporize

Bubbles of vapor form

throughout the liquid

Boiling point – the point

where the vapor pressure

of the liquid is equal to

the external pressure on the liquid

13.2 The Nature of Liquids

Starter S-140

1. What is

A. Vaporization

B. Boiling

C. Evaporation

D. Vapor Pressure

2. What is the relationship between vapor pressure and boiling?

13.3 The Nature of Solids

Chapter 13

Properties of solids are determined by

1. Orderly arrangement of their particles

2. Fixed locations of their particles

Melting point – temperature at

which a

solid

changes

into a

liquid

13.3 The Nature of Solids

The melting point and freezing point are the same temperature

The states are at

equilibrium

Crystalline Solids – the

particles are arranged

in crystals

Crystal – orderly 3D

pattern

13.3 The Nature of Solids

Crystal Systems

Defined by

6 Values

13.3 The Nature of Solids

Seven Basic Shapes

Unit Cell – the

smallest group

of particles that

has the

geometric shape

of the crystal

13.3 The Nature of Solids

Allotropes – two or more different molecular forms of the same element in the same physical state

Carbon

Diamond

Graphite

Soot (buckminsterfullerene)

13.3 The Nature of Solids

Amorphous Solid – lacks an internal structureRubberPlasticsGlass

Do not have aspecific melting point

Shatter into randomshapes

13.3 The Nature of Solids

Starter S-141

1. Define

A. Crystalline Solid

B. Amorphous Solid

2. What are the three allotropes of carbon?

13.4 Changes of State

Chapter 13

Solid – molecules vibrate in place

Melting – Particles increase speed start to move

Liquid – molecules move, but still attracted to each other

Evaporation – particles move fast enough to that intermolecular forces do not matter

13.4 Change of State

Phase Change

Melting

Sublimation – solid goes directly to a gas

Vapor pressure of the solid is greater than atmospheric pressure

Carbon Dioxide (Dry Ice)

Iodine

13.4 Change of State

Phase Diagram – shows states (solid, liquid, gas) in relation to pressure and temperature

13.4 Change of State

Triple Point – the point where a solid, liquid, and gas state can all exist

For water that would be 0.61 kPa and 0.016 oC

Notice – An increase in pressure drives most substances toward a solid

An increase in temperature drives substances toward a gas

13.4 Change of State