The substance which can be used as adsorbent in column chromatography is

Options

A. `Na_(2)O`
B. `Na_(2)SO_(4)`
C. `Al_(2)O_(3)`
D. `NaCl`

Answer

**Step-by-Step Solution:**

1. **Understanding Column Chromatography**:
- Column chromatography is a technique used for separating mixtures. It operates on the principle of adsorption, where different components of a mixture adhere to a stationary phase as they move through a column.

2. **Defining Adsorbent**:
- An adsorbent is a material that allows the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid onto its surface. This is crucial in column chromatography, as the adsorbent is what separates the components of the mixture.

3. **Identifying Common Adsorbents**:
- The most commonly used adsorbents in column chromatography are aluminum oxide (Al2O3) and silica gel. Both of these materials have high surface areas and are porous, which enhances their ability to adsorb various substances.

4. **Properties of Effective Adsorbents**:
- Effective adsorbents should have a high surface area and porosity. This allows them to interact with and hold onto the molecules of the mixture being separated through intermolecular forces.

5. **Conclusion**:
- Based on the understanding of column chromatography and the properties of adsorbents, the correct answer to the question is that substances like aluminum oxide (Al2O3) and silica gel can be used as adsorbents in column chromatography.

**Final Answer**: The substance which can be used as an adsorbent in column chromatography is aluminum oxide (Al2O3) or silica gel.

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