STATES OF MATTER PHASE CHANGES Particle Motion Solid

STATES OF MATTER & PHASE CHANGES

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 available space What misconceptions could be created by the model shown here of particles in a solid, liquid, gas, and plasma?

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

Phase Graphs • Show 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)

Phase Graphs • Phase changes occur at the: ØFreezing/Melting Point = Temp. where SOLID & LIQUID transition ØBoiling/Condensation Point = Temp. where LIQUID & GAS transition

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