Question

Chromatographic technique/s based on the principle of differential adsorption is/are
A. Column chromatography
B. Thin layer chromatography
C. Paper chromatography
Choose the most appropriate answer from the options given below:

• A. B only
• B. A only
• C. A & B only
• D. C only

Answer 1

The Correct Option is C

Chromatography is a technique used for the separation of components in a mixture based on their different affinities towards a stationary phase while being transported by a mobile phase. Different chromatographic techniques employ different principles for separation, one of which is differential adsorption. 

1. Understanding Differential Adsorption:
   • Differential adsorption is based on the varying degrees to which different components in a mixture adhere to a stationary phase.
   • Components that strongly adsorb onto the stationary phase move more slowly compared to those with weaker adsorption, leading to their separation.
2. Analysis of Options:
   • Column Chromatography (A):
     • It utilizes a column packed with a stationary phase (e.g., silica or alumina) and separates compounds based on differential adsorption to the stationary phase.
     • Components that have stronger interactions with the stationary phase will travel slowly through the column.
   • Thin Layer Chromatography (B):
     • Similar to column chromatography, TLC also operates on the principle of differential adsorption.
     • A thin layer of adsorbent (typically silica gel) is spread over a glass or plastic plate, and separation occurs based on adsorbent interactions.
   • Paper Chromatography (C):
     • This technique primarily uses the principle of partition rather than adsorption.
     • Separation is based on differences in solubility and paper as a stationary phase is impregnated with a liquid stationary phase.
3. Conclusion:
   • Column Chromatography and Thin Layer Chromatography both rely on differential adsorption principles.
   • Therefore, the correct answer is A & B only.

Answer 2

Chromatographic techniques that are based on the principle of differential adsorption are:  
- Column chromatography (A)  
- Thin layer chromatography (B)  

Both these techniques operate on the principle of differential adsorption, where components of a mixture are adsorbed to different extents on a stationary phase and thus separate during the process.

The Correct Answer is: A & B only