Chromatographic technique/s based on the principle of differential adsorption is/are A. Column chromatography B. Thin…
Practical Organic Chemistry · Class 11 · JEE Main Previous Year 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
A & B only
Step 1: Define Differential Adsorption
Differential adsorption means different compounds adsorb on a solid adsorbent surface with different strengths. More polar compounds interact more strongly with a polar adsorbent (like silica gel or alumina), while less polar compounds adsorb weakly.
Step 2: Analyse Each Technique
A. Column Chromatography ✅
- Stationary phase: solid adsorbent (silica gel or alumina) packed in a glass column
- Mobile phase: liquid solvent (eluent)
- Separation mechanism: differential adsorption — components travel at different speeds through the column
- Less polar compounds elute first; more polar ones are retained longer
B. Thin Layer Chromatography (TLC) ✅
- Stationary phase: thin layer of silica gel or alumina coated on a glass/aluminium plate
- Mobile phase: liquid solvent
- Separation mechanism: same differential adsorption principle as column chromatography
- Used for quick qualitative analysis and monitoring reactions
C. Paper Chromatography ❌
- Stationary phase: water absorbed in cellulose fibres of the paper (a liquid stationary phase)
- Separation mechanism: differential partition between mobile organic solvent and stationary water film
- This is partition chromatography, NOT adsorption chromatography
Step 3: Summary Table
| Technique | Stationary Phase | Principle | |---|---|---| | Column chromatography | Solid (silica gel / alumina) | Differential adsorption ✅ | | TLC | Solid (silica gel / alumina) | Differential adsorption ✅ | | Paper chromatography | Liquid (water in cellulose) | Differential partition ❌ |
Step 4: Conclusion
Only A and B are based on differential adsorption → Option (c) A & B only
Key Points to Remember:
- Column chromatography and TLC: adsorption principle (solid adsorbent)
- Paper chromatography: partition principle (liquid stationary phase)
- Polar compound → stronger adsorption → lower → elutes last
- Silica gel and alumina are the two standard polar adsorbents in organic chemistry
Practice this question with progress tracking
Want timed practice with adaptive difficulty? Solve this question (and hundreds more from Practical Organic Chemistry) inside The Crucible, our adaptive practice platform.
More JEE Main Practical Organic Chemistry PYQs
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:
Using column chromatography, mixture of two compounds 'A' and 'B' was separated. 'A' eluted first, this indicates 'B' has
From the figure of column chromatography given below, identify incorrect statements. (A) Compound ' c ' is more polar than ' a ' and ' b ' (B) Compound ' a ' is least polar (C) Compound ' b ' comes…
Thin layer chromatography of a mixture shows the following observation: The correct order of elution in the silica gel column chromatography is
Which of the following statement is correct for paper chromatography?