Phase DiagramsA phase diagram shows the conditions at which the distinct phases of matter can occur at equilibrium.

Phase Diagram

Vaporization

Condensation

Sublimation

Deposition

Melting

Freezing

Phase DiagramsTriple Point

The triple point of a substance is the temperature and pressure at which gas, liquid, and solid coexist in thermodynamic equilibrium.

Gas

Liquid

Solid

Phase DiagramsTriple Point

For water, the combination of pressure and temperature are exactly 0.010000 °C and 0.0060373 atm.

At that point, the liquid can boil and freeze at the same time.

Gas

Liquid

Solid

Phase DiagramAccording to the red line on the phase diagram,

if we apply enough pressure to ice, it will melt into liquid water.

What are the practical applications?

Phase DiagramAccording to the red line on the phase diagram,

if we apply enough pressure to ice, it will melt into liquid water.Ice Skating is one application

of this phenomenon.

Phase DiagramsCarbon dioxide

Dry Ice

Phase Diagrams

Dry Ice

Carbon dioxide has a vapor pressure of 830 psi (56.5 atm) at 20 °C.

At 0 °C the pressure inside a CO2 fire extinguisher is about 500 psi. At 30 °C it is about 1000 psi.

Phase DiagramsCarbon