Fick's Law is a mathematical equation used to describe the rate of diffusion of a solute across a membrane or through a barrier. It states that the rate of diffusion (J) of a substance is directly proportional to the surface area (A) and concentration gradient (ΔC) of the substance, and inversely proportional to the thickness of the barrier (d) through which the substance is diffusing. The equation is typically written as J = -D * A * ΔC / d, where J is the rate of diffusion, D is the diffusion coefficient of the substance, A is the surface area, ΔC is the concentration gradient, and d is the thickness of the barrier.
