The principle involved in paper chromatography is

Options

A. adsorption
B. partition
C. solubility
D. volatility

Explanation

**Step-by-Step Solution:**

1. **Understanding Paper Chromatography**: Paper chromatography is a technique used to separate mixtures into their individual components. It is based on the distribution of the components between two phases: a stationary phase and a mobile phase.

2. **Identifying the Phases**: In paper chromatography, the stationary phase is the paper itself, while the mobile phase is the solvent that moves through the paper. The components of the mixture will travel at different rates depending on their affinity for the stationary phase versus the mobile phase.

3. **Partition Coefficient**: The separation occurs due to differences in the partition coefficients of the components. The partition coefficient is a ratio that describes how a substance distributes itself between the two phases. Components with a higher affinity for the stationary phase will move slower, while those with a higher affinity for the mobile phase will move faster.

4. **Relation to Partition Chromatography**: Paper chromatography is a specific type of partition chromatography. In partition chromatography, the separation is based on the continuous differential partitioning of components between the stationary and mobile phases.

5. **Conclusion**: Therefore, the principle involved in paper chromatography is based on the concept of partitioning, which is the differential distribution of components between the stationary and mobile phases due to their partition coefficients.

**Final Answer**: The principle involved in paper chromatography is partition chromatography.

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