1. Chemistry Notes Phase Diagrams

2. Phase Diagrams
 We can graph the effects of temperature and pressure on phase. This kind of graph is called a phase diagram, and it shows the state of matter a substance occupies at a certain temperature and pressure.
 At high pressures and/or low temperatures, the solid state is most likely.
 At low pressures and/or high temperatures, the gaseous state is most likely.
 At high pressure and medium/high temperatures, the liquid state is most likely.

3. The lines between each phase are called phase boundaries
The lines between each phase are called phase boundaries. For example, the line between solid and liquid is the solid-liquid phase boundary; crossing it requires melting a solid or freezing a liquid.

4. The triple point is the temperature and pressure where all three states of a substance can exist.

5. The critical point is the point at which the liquid/gas boundary ends, and substances above this temperature and/or pressure are called “supercritical fluids”.

6. You will need to be able to identify phase changes on a phase diagram
You will need to be able to identify phase changes on a phase diagram. They are labeled on the phase diagram.