diffusion process

Diffusion is a physical process driven by the random motion of molecules. It results in a net flow of matter from an area of high concentration to an area of low concentration. A common example is how the scent of a flower spreads throughout a room.1

In physics, diffusion also describes the transport of thermal energy from hotter to cooler regions, known as heat conduction in fluids. The rate of diffusion is directly proportional to the concentration gradient, represented by the equation (j = -D(dc/dx)), where (j) is the flow rate, (D) is the diffusivity, and (dc/dx) is the change in concentration over distance.1

Osmosis is a specific type of diffusion involving the passage of solvents, like water, through a semipermeable membrane. This membrane allows solvent molecules to pass but blocks dissolved substances (solutes).2