Sorption is the phenomenon :

Options

A. reverse of adsorption
B. reverse of absorption
C. when adsorption and absorption takes place simultaneously
D. None of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Sorption**: Sorption is a term used to describe the process in which one substance becomes attached to another. It encompasses both adsorption and absorption.

2. **Defining Adsorption and Absorption**:
- **Adsorption**: This is the process where molecules adhere to the surface of a solid or liquid.
- **Absorption**: This is the process where one substance is taken up into the volume of another substance, such as a sponge soaking up water.

3. **Analyzing the Options**:
- **Option 1: Reverse of adsorption**: This is incorrect because sorption is not merely the reverse of adsorption.
- **Option 2: Reverse of absorption**: This is also incorrect for the same reason; sorption is not simply the reverse of absorption.
- **Option 3: When adsorption and absorption take place simultaneously**: This is correct because sorption involves both processes occurring at the same time.

4. **Conclusion**: Based on the definitions and analysis of the options, sorption is best defined as the phenomenon where adsorption and absorption occur simultaneously.

5. **Final Answer**: The correct answer is that sorption is the phenomenon when adsorption and absorption take place simultaneously.

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