| A | B |
|---|
| Solid | A closely packed arrangement of particles which have a fixed shape |
| Liquid | The arrangement of particles which can flow over each other but do not have enough energy to escape each other |
| Gas | The arrangement of particles with no fixed shape and the energy to move away from each other |
| Evaporation | The change from a liquid state to a gaseous state |
| Condensation | The change from a gas state to a liquid state |
| Melting | The change from a solid state to a liquid state |
| Freezing | The change from a liquid to a solid |
| Density | The amount of particles packed into a space |
| Diffusion | The random movement of particles with energy |
| Pressure | The force of particles pushing on a surface |
| Vacuum | An area which contains no particles |
| Melting Point | The temperature where a solid changes into a liquid and vice versa (also the freezing point) |
| Boiling Point | The temperature where a liquid changes into a gas an vice versa (also the condensation point) |
