1. Notes #1: Gases
WCHS Chemistry

2. KINETIC MOLECULAR THEORY
“Molecules Move” Theory - a gas consists of small particles that are in constant random motion.
Most of a gas is empty space
This allows us to change the volume!

3. KINETIC MOLECULAR THEORY
The speed of a gas particle is proportional to its temperature…
Higher temp = FASTER movement = LARGER volume = gas EXPANDS
Lower temp = SLOWER movement = SMALLER volume = gas CONTRACTS

4. QUICK NOTE
Explosion & Implosion → aggressive & fast
vs.
Expansion & Contraction→slow & controlled

5. SIMULATION

6. Pressure = force per unit area
Atmospheric Pressure = pressure exerted by the force of the air above
14.7 lbs of pressure per square inch!
About the same as having a small car pressing down on you!

8. In an Airplane
Under water

9. Pressure can be increased by:
Increasing the number of molecules
Blowing up a balloon
Increasing the temperature
Decreasing the volume
Gases ALWAYS go from
HIGH pressure → LOW pressure!

10. CLOSED SYSTEM vs. OPEN SYSTEM
Closed System - an isolated system that CANNOT interact with an outside environment
Open System - a system that CAN interact with an outside environment

11. EXPLOSION vs. IMPLOSION
Explosion - outward movement
Due to high pressure in a closed system
Implosion - inward movement
Due to low pressure in a closed system L H L H