Oils on treating with hydrogen in the presence of palladium or nickel catalyst from fats. This is an example of

Options

A. addition reaction
B. substitution reaction
C. displacement reaction
D. oxidation reaction

Explanation

To solve the question, we need to understand the process described and identify the type of reaction taking place when oils are treated with hydrogen in the presence of a catalyst.

### Step-by-Step Solution:

1. **Identify the Nature of Oils**:
- Oils are primarily composed of unsaturated fatty acids, which means they contain one or more double bonds between carbon atoms.

2. **Understanding Hydrogenation**:
- When oils (unsaturated fats) are treated with hydrogen gas (H₂) in the presence of a catalyst like palladium or nickel, a chemical reaction occurs. This process is known as hydrogenation.

3. **Reaction Mechanism**:
- During hydrogenation, the double bonds in the unsaturated fatty acids react with hydrogen. This results in the addition of hydrogen atoms across the double bonds, converting them into single bonds.

4. **Formation of Saturated Fats**:
- As a result of this reaction, the unsaturated fats (oils) are transformed into saturated fats. Saturated fats do not have double bonds and are typically solid at room temperature (e.g., ghee).

5. **Type of Reaction**:
- The process of adding hydrogen to unsaturated fats to convert them into saturated fats is classified as an **addition reaction**. This is because new atoms (hydrogen) are added to the molecule without removing any atoms.

6. **Conclusion**:
- Therefore, the correct answer to the question is that this process is an example of an **addition reaction**.

### Final Answer:
This is an example of an **addition reaction**.

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