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 and identify mixtures of substances, particularly organic compounds. It is commonly used for analyzing dyes, pigments, and other small molecules.

2. **Principle of Separation:**
The principle behind paper chromatography is based on the differential movement of substances through a stationary phase (the paper) and a mobile phase (the solvent).

3. **Adsorption vs. Partition:**
In paper chromatography, the substances being separated interact with the paper (stationary phase) through adsorption. This means that different substances will adhere to the paper with varying strengths, causing them to move at different rates when the solvent (mobile phase) travels up the paper.

4. **Application of the Principle:**
For example, if a mixture of blue and red dyes is applied to the paper and a solvent is allowed to move up the paper, the dyes will separate based on their different adsorption properties. The blue dye may travel further than the red dye due to its weaker interaction with the paper.

5. **Conclusion:**
Therefore, the correct principle involved in paper chromatography is **adsorption**. The answer to the question is option A.

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

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