What method does paper chromatography use to separate a mixture?

Paper chromatography is a technique used to separate mixtures of substances based on their different affinities towards a stationary phase (the paper) and a mobile phase (the solvent). The separation occurs because the components in the mixture will interact with the paper and the solvent to varying degrees. Some substances will adhere more strongly to the paper, while others will travel further up the paper with the solvent. This process results in different substances moving at different rates, allowing for their separation.

The selected answer accurately reflects this principle of attraction and interaction, highlighting that the mixture's components are distributed between the two phases—stationary (the paper) and mobile (the solvent)—in different proportions. This method is widely used in chemistry for analyzing substances such as inks, dyes, and plant extracts.