Extent of adsorption of adsorbate from solution phase increases with …… .

Options

A. increase in amount of adsorbate in solution
B. decrease in surface area of adsorbent
C. increase in temperature of solution
D. decrease in amount of adsorbate in solution.

Answer

To determine how the extent of adsorption of an adsorbate from the solution phase increases, we need to analyze the provided options based on the principles of adsorption.

### Step-by-Step Solution:

1. **Understanding Adsorption**:
- Adsorption is the process where molecules (adsorbate) adhere to the surface of a solid (adsorbent). The adsorbate is the substance being adsorbed, while the adsorbent is the surface on which adsorption occurs.

2. **Analyzing the Options**:
- **Option A**: Increase in the amount of adsorbate in the solution.
- **Option B**: Decrease in the surface area of the adsorbent.
- **Option C**: Increase in the temperature of the solution.
- **Option D**: Decrease in the amount of adsorbate in the solution.

3. **Evaluating Each Option**:
- **Option A**: When the amount of adsorbate in the solution increases, the likelihood of adsorbate molecules interacting with the adsorbent surface also increases. This leads to a higher extent of adsorption.
- **Option B**: Decreasing the surface area of the adsorbent would limit the available sites for adsorption, thus decreasing the extent of adsorption.
- **Option C**: Increasing the temperature can lead to increased kinetic energy of the molecules, which may reduce adsorption as the molecules may escape from the surface rather than adhere to it.
- **Option D**: Decreasing the amount of adsorbate in the solution would lead to fewer interactions with the adsorbent, thus decreasing the extent of adsorption.

4. **Conclusion**:
- The correct answer is **Option A**: Increase in the amount of adsorbate in the solution. This leads to an increase in the interaction between the adsorbate and the adsorbent, resulting in a higher extent of adsorption.

### Final Answer:
The extent of adsorption of adsorbate from solution phase increases with **increase in the amount of adsorbate in the solution**.

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