Intermolecular Phase Diagrams

Solids

Particles are tightly packed together, have a fixed shape and volume, and cannot be easily compressed.

Liquids

Particles are spaced further apart than in solids, have a fixed volume, take the shape of their container, and are not compressible.

Gases

Particles are very far apart, have no fixed shape or volume, and can be compressed.

Phase Diagrams

Diagrams that show the state (solid, liquid, or gas) of a substance at various pressures and temperatures.

AB Line

Represents the boundary between liquid and vapor (gas), indicating boiling points at specific pressures.

Triple Point (A)

The point where all three states of matter (solid, liquid, gas) can coexist in equilibrium.

Critical Point (B)

The point where liquid and gas become indistinguishable and is known as a supercritical fluid.

AD Line

Marks the boundary between liquid and solid, indicating melting points at different pressures.

AC Line

Represents the sublimation points of the substance at different pressures, where solid turns directly into gas.

Isobaric transitions

Transitions that occur at constant pressure.

Isothermal transitions

Transitions that occur at constant temperature.

Normal conditions

Circumstances at standard atmospheric pressure.

Carbon Dioxide

Cannot exist as a liquid unless the pressure is above 5.11 atm; below that, it sublimates directly from solid to gas.