in analytical chemistry, method for separating mixtures of substances in which a liquid or gaseous solution of the mixture is caused to flow through a tube packed with a finely divided solid, which may be coated with an adsorbent liquid, or through a long capillary tube bearing a thin film of adsorbent liquid; the components of the mixture separate because they travel through the tube at different rates, determined by the degree to which each is retarded by interacting with the stationary material. See also gas chromatography; gel chromatography.