1. STATES OF MATTER
& PHASE CHANGES

2. Particle Motion
Solid – particles tend to move slowly (vibrate) and keep their shape
Liquid – particles move freely and take the shape of their container
Gas – particles move excitedly and fill all available space
What misconceptions could be created by the model shown here of particles in a solid, liquid, gas, and plasma?

3. Argon Ice melting and sublimating at the same moment
Phase Changes
Transfer of thermal energy is required to change the state (or phase) of a substance
Freezing/Melting Point
Boiling/Condensation Point
Argon Ice melting and sublimating at the same moment

4. Phase Graphs
Show how TEMPERATURE changes over TIME can change the state (phase) of a substance. Temperature (y) vs. Heat/Time (x)
Energy Exchange Causing a Rise in Temperature = POSITIVE SLOPE
Energy Exchange Causing a Drop in Temperature = NEGATIVE SLOPE
Energy Exchange Causing a Phase Change = SLOPE OF ZERO (FLAT)

5. Phase Graphs Phase changes occur at the:
Freezing/Melting Point = Temp. where SOLID & LIQUID transition
Boiling/Condensation Point = Temp. where LIQUID & GAS transition

6. Draw your own Phase Graph
Label:
Axes: y = Temperature, x = Heat Energy over Time
Solid, Liquid, Gas
Melting, Freezing, Boiling, Condensing
Melting/Freezing Point, Boiling/Condensation Point
Particle Motion (solid v. liquid v. gas)