The principle involved in paper chromatography is partition.

Partition Chromatography:
Partition chromatography is a type of liquid-liquid chromatography where the stationary phase is a liquid that is immobilized on a solid support. Partition chromatography is based on the principle that the solute distributes itself between the stationary and mobile phases. The stationary phase is a liquid that is immobilized on a solid support, and the mobile phase is a solvent that flows through the stationary phase.

Paper Chromatography:
Paper chromatography is a type of partition chromatography where the stationary phase is paper, and the mobile phase is a liquid solvent. Paper chromatography is used to separate and identify the components of a mixture based on their solubility and partition coefficient.

Principle of paper chromatography:
The principle of paper chromatography is based on the partition coefficient of the components of a mixture between the stationary phase (paper) and the mobile phase (solvent). The components of the mixture are separated as they move at different rates through the paper due to the differences in their partition coefficients.

Conclusion:
In paper chromatography, the principle involved is partition, which is based on the distribution of the components of a mixture between the stationary and mobile phases. Paper chromatography is a useful technique for separating and identifying the components of a mixture based on their partition coefficients.