Kinetic Model of Matter CHANG, FANG-HSIN @ EDISON CHANG PGDE (Sec), July 2006

Kinetic Model of Matter By the end of this lesson, you should be able to: 1. Use Kinetic Model of Matter to: compare the physical properties ; and decribe the molecular structure of the three states of matter: Gas , Liquid and Solid . 2. Understand that Brownian Motion proves Kinetic Model of Matter . 3. Describe the relationship between temperature and molecular motion . 4. Explain pressure of a gas in terms of its molecular motion .

1. Use Kinetic Model of Matter to:

compare the physical properties ; and

decribe the molecular structure

of the three states of matter: Gas , Liquid and Solid .

2. Understand that Brownian Motion proves Kinetic Model of Matter .

3. Describe the relationship between temperature and molecular motion .

4. Explain pressure of a gas in terms of its molecular motion .

Part One

CAN YOU SEE? m a croscopic m i croscopic

CAN YOU SEE? m a croscopic m i croscopic

What is this stuff ? What is the Matter ?

Matter = things , ‘ stuff’ and… YOU

What is Matter ? What are YOU made of ?

Mobile Phone Model to represent the real thing =

Scientific Model = solid to represent the real thing

Scientific Model to represent the real thing = water molecule =

Matter can MOVE Brownian Motion How do we know? Here is the proof 

random movement of Liquid or Gas molecules Brownian Motion Matter can MOVE

Dead Cells Brownian Motion Matter can MOVE http://www-micro.msb.le.ac.uk/video/brownian.mov get pushed around by

Matter can MOVE + = Kinetic Energy

Kinetic Model of Matter Matter is made of moving molecules

Name 3 States of Matter

Name 3 States of Matter Gas Liquid Solid

Kinetic Model of Matter = Gas = flowing water molecule

Kinetic Model of Matter = Liquid = flowing water molecule

Kinetic Model of Matter = Solid = vibrating water molecule

Hold on a second!

Are you telling me that ICE CUBES are actually vibrating ?

!!! YES !!! Are you telling me that ICE CUBES are actually vibrating ?

WHY ?

CAN YOU SEE? m a croscopic m i croscopic

CAN YOU SEE? m a croscopic m i croscopic

m a croscopic Can you see ice cubes vibrate when they are becoming flowing water ?

m a croscopic Can you see ice cubes vibrate when they are becoming flowing water ? NO

vibrating m a croscopic m i croscopic flowing But are ice cubes actually vibrating when they are becoming flowing water ?

vibrating m a croscopic m i croscopic flowing But are ice cubes actually vibrating when they are becoming flowing water ? YES

During melting , ice cubes are vibrating to break the attrative force that holds water molecules together to become flowing water.

Part Two

Kinetic Model of Matter

Kinetic Model of Matter

Who is HOT ???

100 °C 0 °C

Who is HOT ???

Higher Temperature

Kinetic Model of Matter ? Kinetic Energy ?

Kinetic Model of Matter

Kinetic Model of Matter ? Attractive Force ?

Kinetic Model of Matter

Kinetic Model of Matter ? Motion ?

Kinetic Model of Matter Vibrate Flow at fixed position Slow Fast all over the place

Kinetic Model of Matter ? Shape ?

Kinetic Model of Matter Fixed Changing with the shape of container

Kinetic Model of Matter ? Distance between Molecules ?

Kinetic Model of Matter

Kinetic Model of Matter ? Can be Compressed ?

Kinetic Model of Matter NO NO YES! ? Can be Compressed ?

Liquid Nitrogen Gas Nitrogen 25 ° C -72 ° C COMPRESS

Liquid Nitrogen Gas Nitrogen 25 ° C -72 ° C DECOMPRESS

LIVE

Hand burnt by Liquid Nitrogen

Large Volume Small Volume COMPRESS CO 2

Large Volume Small Volume DECOMPRESS CO 2

Large Volume Small Volume DECOMPRESS HOW? CO 2

Large Volume Small Volume DECOMPRESS

DECOMPRESS ? CO 2

DECOMPRESS ? Speed ? Volume ? CO 2

Speed ?

Volume ?

LIVE +

DECOMPRESS ? Speed Faster Volume Larger CO 2

Speed Faster

Volume Larger

Pressure Speed of molecular motion

http://eepybird.com/exp214.html You’ve seen nothing yet!

Homework Play Gas Law Program to find out the relationships between: Pressure Molecular Motion V.S Molecular Motion V.S Temperature

http://intro.chem.okstate.edu/1314F00/Laboratory/GLP.htm Gas Law Program