KINETIC TERMS 10/16/07

Thermal Expansion As particles are heated they begin to move faster and further apart (the substance EXPANDS). As particles are cooled they begin to move slower and come closer together (it CONTRACTS).

Diffusion The movement of particles from an area of high concentration to an area of lower concentration. Diffusion increases with higher temperatures.

Air fresheners work because of diffusion.

Evaporative Cooling As a liquid (ex: water) evaporates off a surface (like your body), heat energy from your body is needed and therefore cools the surface (your skin).

Athletes (and you) sweat to cool body’s core temperature.