What Is Diffusion? Chemistry Definition - ThoughtCo

Diffusion is a natural mass transport mechanism that moves matter from area of high concentration to those of low concentration. Diffusion is a natural mass transport mechanism that moves matter from area of high concentration to those of low concentration. Science Photo Library Ltd / Getty Images by Anne Marie Helmenstine, Ph.D. Updated June 13, 2017 DIFFUSION DEFINITION Diffusion is the movement of a fluid from an area of higher concentration to an area of lower concentration. Diffusion is a result of the kinetic properties of particles of matter. The particles will mix until they are evenly distributed. Diffusion may also be thought of as movement of particles down a concentration gradient. The term "diffusion" comes from the Latin word diffundere, which means "to spread out". DIFFUSION EXAMPLES H2S(g) in a test tube will slowly diffuse into the air of a lab until equilibrium is reached. Food coloring in water diffuses until it's evenly distributed throughout the liquid. Perfume diffuses throughout an entire room. Adding a dot of dye to gelatin is a good example. The color will slowly diffuse throughout the gel. Note, however, most of the common examples of diffusion also illustrate other mass transport processes. For example, when perfume is smelled across a room, air currents or convection are more of a factor than diffusion. Convection also plays a large role in the dispersion of food coloring in water.