In a heterogeneous catalysis which of the following processes takes place

Options

A. Absorption
B. Hydration
C. Adsorption
D. Intermediate compound

Answer

To solve the question regarding the processes that take place in heterogeneous catalysis, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Heterogeneous Catalysis**:
- Heterogeneous catalysis occurs when the reactants and the catalyst are in different phases. For example, if the reactants are gases, the catalyst is typically a solid or a liquid.

2. **Identifying the Options**:
- The options given are:
A. Absorption
B. Hydration
C. Adsorption
D. Intermediate compound

3. **Analyzing Each Option**:
- **A. Absorption**: This process involves the incorporation of a substance into another substance. In heterogeneous catalysis, this is not the primary process.
- **B. Hydration**: This refers to the process of adding water to a substance, which is not specifically related to heterogeneous catalysis.
- **C. Adsorption**: This is the process where molecules from a gas or liquid adhere to the surface of a solid catalyst. This is a key process in heterogeneous catalysis.
- **D. Intermediate compound**: While intermediate compounds may form during reactions, they are not a process that characterizes heterogeneous catalysis.

4. **Conclusion**:
- The correct process that takes place in heterogeneous catalysis is **C. Adsorption**. This is because adsorption is essential for the catalyst to interact with the reactants on its surface.

### Final Answer:
The correct answer is **C. Adsorption**.

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