In which of the following process adsorption plays
an important role?
(a) Froth floatation process
(b) Chromatographic analysis
(c) Control of humidity
(d) heterogeneous catalysis

Options

A. b' 'c' & 'd' only
B. a' 'b' & 'd' only
C. b' & 'd' only
D. All 'a' 'b' 'c' & 'd'

Answer

To determine in which of the given processes adsorption plays an important role, let's analyze each option step by step:

### Step 1: Analyze the Froth Floatation Process
- **Explanation**: In the froth floatation process, minerals are separated based on their hydrophobic properties. The process involves the adsorption of certain particles onto air bubbles, which then rise to the surface, allowing for the separation of valuable minerals from the gangue.
- **Conclusion**: Adsorption plays a crucial role in this process.

### Step 2: Analyze Chromatographic Analysis
- **Explanation**: Chromatography is a technique used to separate mixtures. It relies on the differential adsorption of compounds onto a stationary phase. As the mixture moves through the stationary phase, different components are adsorbed to varying degrees, leading to their separation.
- **Conclusion**: Adsorption is fundamental to chromatographic analysis.

### Step 3: Analyze Control of Humidity
- **Explanation**: Control of humidity often involves the use of adsorbents like silica gel, which adsorbs moisture from the air. This process helps in maintaining desired humidity levels in various environments.
- **Conclusion**: Adsorption is important in controlling humidity.

### Step 4: Analyze Heterogeneous Catalysis
- **Explanation**: In heterogeneous catalysis, the reactants are adsorbed onto the surface of a solid catalyst. This adsorption is essential for the reaction to occur, as it brings the reactants closer together and facilitates the reaction.
- **Conclusion**: Adsorption is a key aspect of heterogeneous catalysis.

### Final Conclusion
After analyzing all four processes, we can conclude that adsorption plays an important role in all of them:
- (a) Froth floatation process: Yes
- (b) Chromatographic analysis: Yes
- (c) Control of humidity: Yes
- (d) Heterogeneous catalysis: Yes

Thus, the correct answer is that adsorption is important in **all of the processes** listed (A, B, C, D).

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