Brownian motion
polllen grain
dusty particles
THE MODEL OF PARTICULATE NATURE OF MATTER
Matter is made up of small discrete particles
All particles of one pure subtance are identical
Particles of all matter are in constant and random motion
MODEL STATE OF MATTER
How many state are there in the natural environment?
Solid
Gas
Liquid
Particulate model of solid
Held together by very strong forces of attraction
Definite shape and volume
Movement
Particles
Unable to move about freely
Vibrate about their fixed position
Arrangement
Packed very closely together
A fixed regular pattern
Physical
properties
Higher density than liquids and gases
Cannot be compressed
Particulate model of liquid
Movement
Particles
Held together by strong forces of attraction
Able to slide past one another
Arrangement
Packed closely together
No fixed, regular pattern
Physical
properties
No definite shape
Lower density than solid
Cannot be compressed
Fixed volume
Particulate model of gas
Movement
Particles
Held together by weak forces of attraction
Able to move about freely over long distance
Arrangement
Far apart from one another
No fixed, regular pattern
Physical
properties
No definite shape or volume
Lowest density
Can be compressed
MODELS OF

EXPANSION AND

CONTRACTION
Influence of temperature on particle motion and thermal expansion
Volume is changed
APPLICATION OF EXPANSION!
expansion upon heating
contraction upon cooling
The mass of a matter is conserved
GLOBAL WARMING
solid
liquid
The particles break free
from one another and move randomly
Melting
Freezing
The particles move closer to one another and move less randomly
Model of changes in state
Model of changes in state
The particles break free
from one another and move randomly
Boiling
Condensation
steam
liquid water
The particles move closer
Figure. The relationship between energy level and temperture when the matter is changed state
What processes do you
need add energy?
What processes does it release energy?