1. LECTURE 7.2 – HPHASE DIAGRAMS

2. Today’s Learning Targets
7.3 – I can draw a phase diagram to describe how pressure and temperature are related and discuss what a triple point is.
7.4 – I can analyze and draw a heating curve to describe how energy is lost or gained while a substance changes phases. I can identify on the graph the Hfusion and the Hvaporization.
7.5 – I can describe a reaction using the ideas of enthalpy and entropy.

3. How are pressure temperature and phase related?

4. I. Pressure and Temperature
The state of matter of a substance depends on both the temperature and pressure
A phase diagram is a graph temperature, pressure, and phase for a substance

6. II. Important Points on a Phase Diagram
Triple Point – The temperature and pressure conditions at which the solid, liquid, and gas phases of a substance coexist
Critical Point – The temperature and pressure at which the gas and liquid state become identical and form one phase.

8. Melting/Fusion Freezing Vaporization Condensation Sublimation
Print out. Have students label in their notes as you go through this graph.
Sublimation
Deposition

9. Class Example
You have a solid at a pressure of 30 atm and -15 oC, if you decrease the pressure at constant temperature, what phases will the substance go through?

10. Table Talk

11. Stop and Jot
Atmospheric pressure on Mt. Everest is 0.29 atm. What is the boiling point of water there using the phase diagram below.