Phase Diagrams (12.2.5)

Question 1

What can a phase diagram help us predict?

Answer 1

• A phase diagram is useful for predicting the phase of a substance at any pressure and temperature.

Question 2

What are the triple point and the critical point?

Answer 2

• At the triple point all three phases of a substance coexist, while beyond the critical point a substance is a supercritical fluid.

Question 3

What do the phase diagrams for carbon dioxide (CO2) and water (H2O) illustrate?

Answer 3

• The phase diagram for carbon dioxide (CO2) illustrates its ability to sublimate, while the phase diagram for water (H2O) illustrates its unusual property of being less dense as a solid than a liquid.