Kow (Distribution Coefficient)

Kow, or the distribution coefficient, measures how a substance divides itself between two immiscible liquids—usually water and an organic solvent—at equilibrium. It indicates whether a chemical prefers to stay in water (polar environment) or move into the organic phase (non-polar environment). A high Kow value means the substance is more soluble in the organic phase, while a low value suggests it favors water. This helps predict how chemicals behave in the environment, such as how they spread, persist, or bioaccumulate in soil, water, and living organisms.