States of Matter

Kinetic-Molecular Theory (KMT)

Describes the behavior of matter in terms of particles in motion.

Elastic collisions

Collisions where no kinetic energy is lost; energy can be transferred between particles.

Gas Pressure

The force per unit area exerted by gas particles.

Diffusion

The movement of one material through another, occurring from high to low concentrations.

Effusion

The process by which a gas escapes through a tiny opening.

Atmospheric Pressure

The pressure exerted by the weight of air in the atmosphere.

Intramolecular Forces

Attractive forces that hold particles together in bonds.

Intermolecular Forces

Forces between different types of particles; generally weaker than intramolecular forces.

Viscosity

A measure of a liquid's resistance to flow.

Surface Tension

The energy required to increase the surface area of a liquid by a given amount.

Crystalline Solid

Solid where particles are arranged in an orderly, geometric, 3D structure.

Endothermic Processes

Phase changes that require the addition of heat, such as melting and vaporization.

Exothermic Processes

Phase changes that release heat, such as freezing and condensation.

Phase Diagram

A graph showing the relationship between pressure and temperature for a given substance.

Triple Point

The condition at which all three phases (solid, liquid, gas) coexist in equilibrium.