The adsorbent used in adsorption chromatography is/are: A. silica gel, B. alumina, C. quick lime, D. magnesia. Choose the most appropriate answer from the options given below:

• Silica Gel (A): A highly porous, chemically inert form of silicon dioxide with a strong affinity for polar compounds.
• Alumina (B): Aluminium oxide, another widely used polar stationary phase available in acidic, basic, or neutral forms.
• Quick Lime (C) & Magnesia (D): Not commonly utilized as primary adsorbents in standard adsorption chromatography techniques.

Conclusion:

Silica gel and alumina are the two classic, standard solid adsorbents employed to separate mixtures based on differential adsorption.

Answer: Option D — A and B only